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Technik => Tech-Talk Marshall => Thema gestartet von: dukeamps am 3.12.2010 10:54
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Hallo Leute,
hier ist ein Amp, den ich modifiziert habe. Original war es ein Trainwreck Express Amp. Hier sind ein paar Clips, wie der Amp klingt.
http://soundclick.com/share.cfm?id=9934173
http://soundclick.com/share.cfm?id=9646821
http://soundclick.com/share.cfm?id=9937439
Falls Ihr Lust habt den Mod auszuprobieren, folgt der folgenden Beschreibung:
Als erstes modifiziert den Amp zu einem 2203 oder 2204
Der input resistor ist 33k, wendet den shield Trick am input an, das shield geht zur Anode anstelle zur Erde. Dann setzt einen 500pf cap über den zweiten plate resistor, .1uf über den 10k, .68uf über den 820r, 1000pf bright cap, 500pf klingt auch gut, der tone stack ist 33k/500pf. Das Wichtigste ist, b+ auf 390v herunterzubringen, dann den Bias für die el34 auf 31.5ma - so bekommt man den brown sound in den Mix.
NFB ist 47k/.1uf/.68uf (was immer am besten gefällt), 4ohm tap. Fizz cap ist 100pf
Die Transformer sind original vom Trainwreck Amp, gekauft von Marstran, der PT hat schon den niedrigeren b+ daher braucht man keine zener dioden um ihn herunterzubringen. Ich habe den Choke auch dort gekauft, aber man kann das an jedem Amp ausprobieren und sehen, wie es klingt, man mus nur sicherstellen, dass man das b+ bei einem 50W jmp Amp von 440v auf 390v herunterbringt, bei einem 100W jmp Amp von 480v auf 430v.
Cheers
Nigel
PS: Versucht dies nur, wenn Ihr wisst was Ihr tut. Oder ich kann es auch für Euch machen.
Sorry, da meine Muttersprache englisch ist, habe ich ein paar englische Begriffe im Text gelassen, ich hoffe, Ihr könnt meiner Beschreibung trotzdem folgen. Ansonsten fragt mich einfach.
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Hallo Nigel
Sounds pretty good - the "ain't talking" clip is my personal favorite.
Der input resistor ist 33k, wendet den shield Trick am input an, das shield geht zur Anode anstelle zur Erde.
I am not sure about this, but read this quite often last time - what does it do exactly? I think it is kind of capacitor effect and therefore I would use a cap ... or is it kind of negative feedback, because of interference?
Dann setzt einen 500pf cap über den zweiten plate resistor,
I think this is to limit harsh sounding highs and upper mids and to give the tone more crunch.
.1uf über den 10k,
I would lower it 3k3 ;-) This will make the crunch a little bit harder sounding.
.68uf über den 820r, 1000pf bright cap, 500pf klingt auch gut,
Actually - while working on a similar project - I altered the values of the cathode, but this depends on personal taste; in order to "copy" the "brown sound" a lil' more, I would recommend using 1k || 330µF or at least 100µF.
The bright caps could be choosen using a multiple switch with multiple values connected ;) I think 1nF is the highest value to use.
der tone stack ist 33k/500pf.
The "original one" is 56k and 250pF according to the schem of an '68 100 watter ...
Das Wichtigste ist, b+ auf 390v herunterzubringen,
Referring to a Marshall 2204 schem you should have 365 volts at the plates of the power tubes.
dann den Bias für die el34 auf 31.5ma - so bekommt man den brown sound in den Mix.
NFB ist 47k/.1uf/.68uf (was immer am besten gefällt), 4ohm tap. Fizz cap ist 100pf
The 100pF will make the sound a little bit darker (at least so it sounds to me) - some people state, that compression increases, too.
Sorry, da meine Muttersprache englisch ist, habe ich ein paar englische Begriffe im Text gelassen, ich hoffe, Ihr könnt meiner Beschreibung trotzdem folgen.
My native language is German, but I see this as a good chance to trainee my English once more.
Regards, Dietmar
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Hi Dietmar thanks for your feedback. :bier:
So like I said before the amp was a trainwreck express amp, and the idea behind this amp was a sort of mix between a brown sound and #34 mod amp.
When you use the anode as shield it takes a lot of noise and oscillation & fizz away its a neat trick, on the #39 amp it had it on the first three stages or so I believe, it also gives the amp that nice sound. I have tried a lot of different values, but that’s just where I thought it sounded best, but if you or anyone else wants to try this mod of course mess about a bit and see what comes out, my values are just guide lines. On the jcm 800 sche I have seen its 33k/470pf, but I could be wrong. With the b+ I was just going with my jmp 50w which has 440v, didn't know that the jcm 800s had so a low b+ 365v.
It’s nice that we can use English here also.
Cheers :)
Nigel
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Hi,
I am not sure about this, but read this quite often last time - what does it do exactly? I think it is kind of capacitor effect and therefore I would use a cap ...
because of the amplification of the stage the capacity of the shielded cable is multiplied by the amplification factor. An easier and safer way is to use a small cap from grid to ground. I am not a fan of anode-grid caps. Why? What will happen in case of failure?...
The combination of these mods (500pF || ra; input-c; fizz cap, lower voltage) will reduce the highs a lot. So on the one hand you will reduce treble with these mods, on the other hand you will get your highs back in the power amp when using a 100k at the 4 Ohm tap in the feedback circuit in combination with the 100nF parallel to the 10k. This smoothens the sound a bit, but the small feedback voltage still gives you a harsher sound.
Another way is to let the highs "flow" through the amp with as few (bypass-)caps as possible and make it smooth with a higher feedback. This will give you a more shimmering sound. It is just upon you!
100pF as a fizz cap reduces these shimmering highs a lot, for my taste it is too big. 50pF is good, 68pF will also work.
and: nice sounding amp
Yours,
Marc
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Hi Nigel
So like I said before the amp was a trainwreck express amp, and the idea behind this amp was a sort of mix between a brown sound and #34 mod amp.
Seems as if we share the same ideas at the same time ;)
I am not sure about the #34 values - at least I have got three different schems, which are based on a mv circuit; I think all of them come very close to VH-I and -II sound and also to Slash' "use your illusion".
When you use the anode as shield it takes a lot of noise and oscillation & fizz away its a neat trick,
Ok, then it is a capacitance - I would beg there is a small amount of negative feedback because of the interference of shield and wire.
on the #39 amp it had it on the first three stages or so I believe, it also gives the amp that nice sound.
Hm ... I think it will smoothen the amp a bit, yes.
I have tried a lot of different values, but that’s just where I thought it sounded best, but if you or anyone else wants to try this mod of course mess about a bit and see what comes out, my values are just guide lines.
As we are dealing with electronic parts which are belonging to the dinosaurs age, you will have enough drift within the values of the parts, so everybody will tweak them to his personal taste and hearing. :)
On the jcm 800 sche I have seen its 33k/470pf, but I could be wrong.
No, you are right. I think Marshall changed them values from 56k / 250pF to 33k / 470pF very early but not on all models. As Eds amp is stated as an '68 plexi, the values could have been 56k / 250pF, if they have not been changed.
With the b+ I was just going with my jmp 50w which has 440v, didn't know that the jcm 800s had so a low b+ 365v.
I think during the JMP era Marshall used the same PTs for 100 and 50 watter - I have never measured the voltages of my JCM800 2204, but the schem shows that low voltage and it is sounding completely different to an JCM800 2203.
It’s nice that we can use English here also.
So, why not? ;)
I am glad that you 've understood me ... ;)
Regards, Stone
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Hi Marc
because of the amplification of the stage the capacity of the shielded cable is multiplied by the amplification factor. An easier and safer way is to use a small cap from grid to ground. I am not a fan of anode-grid caps. Why? What will happen in case of failure?...
That 's what I have in mind, but to be honest, I do not care much about anode-grid caps ... on the other hand side, you are right, grid-cathode caps seem to be much safer.
Regards, Dietmar
EDIT: sorry, mixed it up ... I am using anode caps most of the time - anode-grid caps will result in negative feedback, which is different to effect of anode caps
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Hi,
because of the amplification of the stage the capacity of the shielded cable is multiplied by the amplification factor. An easier and safer way is to use a small cap from grid to ground. I am not a fan of anode-grid caps. Why? What will happen in case of failure?...
The combination of these mods (500pF || ra; input-c; fizz cap, lower voltage) will reduce the highs a lot. So on the one hand you will reduce treble with these mods, on the other hand you will get your highs back in the power amp when using a 100k at the 4 Ohm tap in the feedback circuit in combination with the 100nF parallel to the 10k. This smoothens the sound a bit, but the small feedback voltage still gives you a harsher sound.
Another way is to let the highs "flow" through the amp with as few (bypass-)caps as possible and make it smooth with a higher feedback. This will give you a more shimmering sound. It is just upon you!
100pF as a fizz cap reduces these shimmering highs a lot, for my taste it is too big. 50pF is good, 68pF will also work.
and: nice sounding amp
Yours,
Marc
Hi Marc, thanks for the feedback :bier:
Nigel
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Hi stone, Here's what i know about the #34 mod. First mod to a 2203. Over the 10k put a.1uf, over the 820r/1k put .47uf or.68uf, over the second plate resistor put a 470pf cap & on the gain pot, put a 150k from the wiper to ground. I also believe there was a 1000pf on the gain pot.
The Nfb 47k or 100k/ .1uf or .68uf on the 4ohm tap.
Try and see what you think
Cheers :bier:
Nigel
Ps your English is very good :)
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Hi
die Sounds hören sich Klasse an. Wie hast Du denn die Aufnahmen gemacht?
Gruß, Bernd
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Hi
die Sounds hören sich Klasse an. Wie hast Du denn die Aufnahmen gemacht?
Gruß, Bernd
Hi Bernd,
Vielen Dank für das schöne feedback.
Für die Aufnahme habe ich ein Sennheiser E606 verwendet und es genau zwischen Außen- und Innenrand vom Lautsprecher platziert, ungefähr 10cm weg vom Lautsprecher.
Die Lautsprecher sind vom Typ Celestion G12H30 Heritage.
Gruß Nigel :)
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Hi Nigel
Thanks for the compliment :)
As I have little time until evening, one question in between: would you please be so kind to measure voltage at anode of very first triode?
The rumours about #34 are from having every stage lowered to 2k7 || .68µF up to the things you mentioned - as I am not that much in Slash tones, I do not care about them really, but they are a very good starting point for Eds sound.
BTW: my favorite one is "1984" sound, esp "girl gone bad" and "panama" - I think there is a major / big change in Eds sound from pre-1984 albums to 1984.
Regards, Dietmar
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Hi Nigel
Thanks for the compliment :)
As I have little time until evening, one question in between: would you please be so kind to measure voltage at anode of very first triode?
The rumours about #34 are from having every stage lowered to 2k7 || .68µF up to the things you mentioned - as I am not that much in Slash tones, I do not care about them really, but they are a very good starting point for Eds sound.
BTW: my favorite one is "1984" sound, esp "girl gone bad" and "panama" - I think there is a major / big change in Eds sound from pre-1984 albums to 1984.
Regards, Dietmar
Hi Dietmar, so the first triode anode measured 169v.
Cheers
Nigel
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Hi Nigel
Tried to lower them, too, but average voltage is stated as 192v on anode of the 2k7 system and I got 202 volts - wondering, why this / my 2204 has that much, but it is built in 1980 / 81, so the transformer might be quiet the same as on the 2203 models.
Hm ... I will try to come close to 170 volts tomorrow - maybe I am able to make some sound files, too.
Regards, Stone
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Hi Nigel
Tried to lower them, too, but average voltage is stated as 192v on anode of the 2k7 system and I got 202 volts - wondering, why this / my 2204 has that much, but it is built in 1980 / 81, so the transformer might be quiet the same as on the 2203 models.
Hm ... I will try to come close to 170 volts tomorrow - maybe I am able to make some sound files, too.
Regards, Stone
Hi stone, maybe you have to use some zener diodes to bring the voltage down. I have ordered some of these here, http://cgi.----.de/ws/----ISAPI.dll?ViewItem&item=250474373375&ssPageName=STRK:MEWNX:IT
To try them in my 100w amp.
Cheers
Nigel
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Hi
I am using resistors ... did you place the diodes between center tap of the PT and ground (so CT gets "removed" from ground)? Or do you place them - as some people advice - between B+ and anodes?
Regards, Dietmar
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Hi
I am using resistors ... did you place the diodes between center tap of the PT and ground (so CT gets "removed" from ground)? Or do you place them - as some people advice - between B+ and anodes?
Regards, Dietmar
Hi Dietmar, I'm still waiting for them to come in the post. The amp that I have posted here has a Trainwreck express power transformer in it, & that has already a lower b+, say a normal jmp 50w have 440v on pin 4 of the power tubes & that amp has 390v. Check your voltage on pin 4 of your power tubes & see what that measures.
I'm still trying to figure out where to put these zener diodes, I have read the negative side of the bridge rectifier to ground works. I have also read that with resistors you can get to much sag.
Cheers
Nigel
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Hi
Tried lowering B+ with resistors and it was working quiet well, but I have to say that I only lowered B+ of the triodes and not of the EL34; at plates of the power amp section I can measure about 420 volts ... I think lowering to 390 will give that extra crunch while biasing a little too hot.
Unfortunately I cannot make any recordings which will be of a good quality, because I can record with my camcorder only and even if I connect a Sennheiser mic to it, it just distorts the sound.
I will try to make some recording with "room sound" - maybe it lowers the input level.
At least I raised B+ again to its original specs I noticed nearly no change, so this seems to have a major effect on power tubes.
Regards, Stone
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Hi
Tried lowering B+ with resistors and it was working quiet well, but I have to say that I only lowered B+ of the triodes and not of the EL34; at plates of the power amp section I can measure about 420 volts ... I think lowering to 390 will give that extra crunch while biasing a little too hot.
Unfortunately I cannot make any recordings which will be of a good quality, because I can record with my camcorder only and even if I connect a Sennheiser mic to it, it just distorts the sound.
I will try to make some recording with "room sound" - maybe it lowers the input level.
At least I raised B+ again to its original specs I noticed nearly no change, so this seems to have a major effect on power tubes.
Regards, Stone
Hi stone, Have you tried this mod? It would be nice to hear how your amps sounds. I think you have to lower both the power & preamp tubes to get that crunch. On the power transformer i have used, i have 3 taps 240v= 385v, 230v= 400v, & 220v= 415, the 240v with 385v on the plates sounds the best.
Cheers :bier:
nigel
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Hi Nigel
Surprisingly I did some recordings with "room sound" which come close to what you will hear live .... have a look at http://mirror.stones-amp-inn.de/evh.mpg (http://mirror.stones-amp-inn.de/evh.mpg) and let me know. You will see me bright caps switching with switches on the back of the amp btw.
The cab is loaded with V30s and Craaft Speaker, which give a little smoother top - a little bit contrary to the sound being hunted. The guitar is a selfmade Strat, as shown on TT Forum meeting in September, loaded with a GFS Fat PAT at bridge and a Rockinger Blade Screamer at neck - the neck itself is a Warmoth one (boatneck), full scalloped.
The aspect ratio of the video does not fit (must be 16:9, not 4:3), but I think you won't hear the difference ;) Just kidding. And no, it is not my kitchen, but my amp cooking room ;)
Regards, Stone
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Hi Nigel
Surprisingly I did some recordings with "room sound" which come close to what you will hear live .... have a look at http://mirror.stones-amp-inn.de/evh.mpg (http://mirror.stones-amp-inn.de/evh.mpg) and let me know. You will see me bright caps switching with switches on the back of the amp btw.
The cab is loaded with V30s and Craaft Speaker, which give a little smoother top - a little bit contrary to the sound being hunted. The guitar is a selfmade Strat, as shown on TT Forum meeting in September, loaded with a GFS Fat PAT at bridge and a Rockinger Blade Screamer at neck - the neck itself is a Warmoth one (boatneck), full scalloped.
The aspect ratio of the video does not fit (must be 16:9, not 4:3), but I think you won't hear the difference ;) Just kidding. And no, it is not my kitchen, but my amp cooking room ;)
Regards, Stone
Hi stone, sounds like you have a nice crunch going on there, What are the specs on the amp?
cheers :)
Nigel
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Thanks, Nigel.
Yes, it sounds like crunch, which is a little bit richer or even fatter than usual, but the cam adds a little bit of compression to it and eats a little bit of the bite on top of the sound, but not that much as expected. Maybe the cam is much closer to the sound than my own impression and the effect is based on the Craaft speakers - which I play them for ...
The specs are rather easy ... I reversed your setup in a way and changed some values: 1st 100k:10k|220µF, 2nd 100k:2k7|.68µF, 3rd 100k:3k3|220µF. In between the stages I am using 500pF bright caps and the usual voltage dividers, but the "upper resistor" acting as grid stopper.
2nd anode is bypassed by a 500pF cap, but I am not sure, if this too much and I think I will give 250pF down to 50pF a try; also I added a cap to anode/grid of first stage, 100pF value, but this seems to be too high, too.
Tone stack is stock. 33k and 500pF, 25k pot for mids. Setting is gain 4, treb 5, mid 10, bass 5, pres 5, mv to around three and a half (log 1M pot).
B+ must be rather high, as I removed my "lowering" resistors.
Regards, Stone
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Hi stone, i have tried the 10k on v1 & found that you lose too much gain. The 220ufs are they not too high? Try the shield trick on the input cable see what you think of it. Here's how its done again, your shield cable has an outer core that usually goes to ground, just put that on the anode of the first tube & don't connect the other side to anything, it takes so much noise away. Here's a pic, its not the best but you can see how its done. http://picasaweb.google.com/Stratocaster64/Plexi02?authkey=Gv1sRgCNi9_dnO2oj2Vw#5354732783598173362 these are pics from a Tim Caswell modded amp.
I have actually tried this mod & it sounds very good. Have to do some recordings next week.
Cheers :)
Nigel
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Hi Nigel
Actually I did not use any shielded cable within the amp (will give it a try) as I did in all the others, because it was stock before starting to modify it. The 10k reduces gain, that 's true, but taken as v1 it acts like a booster in front of the treble channel of an 1959 (also I did not use the 2n2 coupling cap of that channel).
On the other hand side the 3k3 on 3rd triode does also reduce the gain a bit, but I think it makes the crunch sound even harder than using a 1k or 820 ohms resistor and the next stage is the cathode follower.
The 220µF are a choice of what I had to hand, because one of the #34 specs I found stated 330µF. You can go down to 100µF, which will give you the same bass response - I think the 330µF are related to the original 330µF | 820 ohms cathode of a 1959.
Has been a long time ago I was on the run for Eds sound, but now it was more a product by random ;)
I was seeking for #34 mod schem and found those different specs for it - tried the first one and found that it comes close to what is called "brown sound". And as I said, Ed himself altered his sound during the albums, so - to my opinion - it is hard to speak of "that brown sound" ...
Most people refer to VH-I as brown sound, which comes close to your modification and sound example. I do prefer the later albums and songs, where the sound became more crunchy and less saturated.
Hard to explain ... "mean street", "somebody get me doctor", "Romeos delight" and "girl gone bad" are my favorite songs. And most of the times I was seeking for Eds sound I referred to those songs.
Let 's see where this journey takes me ;)
Regards, Stone
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Hi stone, really like that evh tone, I was just listening to the songs on youtube. I have also seen that sche with the 330uf, I don't believe that, I think that’s what Tim Caswell said to confuse everyone, but I could be wrong ;)
If you try that mod post a clip to compare it with mine.
Cheers
Nigel :)
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Hi Nigel
I think I will stay with that fat crunch at least, but I will give your mod a try (maybe without lowering B+) and see if I can make a recording next days.
Regards, Stone
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Hi Nigel
I think I will stay with that fat crunch at least, but I will give your mod a try (maybe without lowering B+) and see if I can make a recording next days.
Regards, Stone
Hi stone, sounds good:) I have also that mod in my other 50w amp without lowering the b+ & it has a real good rock tone.
It would be nice to hear how yours sounds too.
Cheers :)
Nigel
Ps it could be that with the higher b+ the 1000pf bright cap is too much.
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Hi Nigel
Done ... but it is loud as hell - it was before, but this must be hell² :devil: The sound is too loud as that I can make any recordings / videos with an appropiate quality - will try this next days with a power soak / brake. :headphone:
There is not much difference, I think: my 2204 sounds harder which must be because of higher B+ and maybe because of OT (which is a Drake / Marshall). I used a 250pF across second anode resistor which lowers the highs but not that much - even the fizzle is gone (47pF as PI anode cap).
It reacts much more to harmonics like the c, b played in "ain't talking" after the a, g chords.
Maybe I had a bad solder before because of its volume now, I have to look for it - it is not possible to play it for about half a minute :( On the other hand side, even if there are average voltages stated within the Marshall schematic, I got 60 volts more on the plates than stated (425 volts instead of 365) and I do not know why.
Hm ... I will have a closer look to the PT and its wiring.
Regards, Stone
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Hi Nigel
Done ... but it is loud as hell - it was before, but this must be hell² :devil: The sound is too loud as that I can make any recordings / videos with an appropiate quality - will try this next days with a power soak / brake. :headphone:
There is not much difference, I think: my 2204 sounds harder which must be because of higher B+ and maybe because of OT (which is a Drake / Marshall). I used a 250pF across second anode resistor which lowers the highs but not that much - even the fizzle is gone (47pF as PI anode cap).
It reacts much more to harmonics like the c, b played in "ain't talking" after the a, g chords.
Maybe I had a bad solder before because of its volume now, I have to look for it - it is not possible to play it for about half a minute :( On the other hand side, even if there are average voltages stated within the Marshall schematic, I got 60 volts more on the plates than stated (425 volts instead of 365) and I do not know why.
Hm ... I will have a closer look to the PT and its wiring.
Regards, Stone
Hi stone, yes with all that boosting it will blow your ears off :laugh: Did you try the shield trick? also if you have too many highs put the 500pf on the first 100k plate resistor instead of the second. What bright cap did you use? How do you like that mod?
Cheers :)
Nigel
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Hi Nigel
I will try it with a soak - I modded my 2203 to #39 specs and it has less volume; even with mv set to 2 (and it 's a log pot) you have the impression the amp is turned up to 10.
I am using a 470pF across the 470k which comes right before gain (gain is bypassed with 1nF) and left the 470k / 470k following voltage divider unpassed, only the 250pF across the 2nd anode. Cathodes are 2k7 || 680nF, 10k || 1µF, 820 || 680nF. All anode resistors are 100k.
I left the 100pF anode to cathode cap on the first stage and the mod is sounding very "versatile" to me - smooth highs with a little sparcle on it but without getting too thick, I would say ... I got the impression that the missing 470pF on the 470k voltage divider normally gives a certain amount of fizzle - but not sure about that.
How do I feel about that mod ... ? To be honest: it makes me love them Marshall beasts again ;) I have been playing Marshalls for a long time and I think most of the newer ones are missing character, sounding too smooth etc. I always stick to the master volumes but at least I was unhappy with them because being too harsh and inflexible, that 's why I tried that #39 mod (and tweaked it later on).
I think I will give a try on next Monday while practicing with the band.
Regards, Stone
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Hi Nigel
I will try it with a soak - I modded my 2203 to #39 specs and it has less volume; even with mv set to 2 (and it 's a log pot) you have the impression the amp is turned up to 10.
I am using a 470pF across the 470k which comes right before gain (gain is bypassed with 1nF) and left the 470k / 470k following voltage divider unpassed, only the 250pF across the 2nd anode. Cathodes are 2k7 || 680nF, 10k || 1µF, 820 || 680nF. All anode resistors are 100k.
I left the 100pF anode to cathode cap on the first stage and the mod is sounding very "versatile" to me - smooth highs with a little sparcle on it but without getting too thick, I would say ... I got the impression that the missing 470pF on the 470k voltage divider normally gives a certain amount of fizzle - but not sure about that.
How do I feel about that mod ... ? To be honest: it makes me love them Marshall beasts again ;) I have been playing Marshalls for a long time and I think most of the newer ones are missing character, sounding too smooth etc. I always stick to the master volumes but at least I was unhappy with them because being too harsh and inflexible, that 's why I tried that #39 mod (and tweaked it later on).
I think I will give a try on next Monday while practicing with the band.
Regards, Stone
Hi stone, what type of mv are you using?
Nigel
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Hi Nigel
It 's the "normal" one, following the tone stack, 1Meg log potentiometer, followed by a 220k resistor in series off the whiper.
From that point of view it shouldn't be as loud as it is.
Regards, Stone
p.s: re-checked my wiring once more and there is no error - maybe a good chance to give "power scaling" a try ...
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Hi Nigel
It 's the "normal" one, following the tone stack, 1Meg log potentiometer, followed by a 220k resistor in series off the whiper.
From that point of view it shouldn't be as loud as it is.
Regards, Stone
p.s: re-checked my wiring once more and there is no error - maybe a good chance to give "power scaling" a try ...
Hi Stone, If you use the normal 1 like on the 2203/2204 layout there is no 220k in series, it goes directly to the 0.022uf cap. Here is good schem if you want to switch the bypass cap on & off, with this schem you get no clicking noise, http://img258.imageshack.us/img258/128/3in1cath.jpg
Nigel
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Hi stone, here is a layout from the metro forum of the #34 mod.
http://img39.imageshack.us/img39/3811/slash34.jpg
The 470pf over the first 100k should be over the second 100k. The .47uf over the 1k can be a .68uf for more beef.
The 150k from the gain pot to ground just takes the gain down, you can just leave that out for more gain.
Cheers
Nigel
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Hi Nigel
Calculating a little bit around with a stock mv preamp and that modded one (1µF across 10k resistor and 680nF across 820 (1k)) ... and it shows, that the modded version gives around 12 to 15dB more output (in practice) to the phase inverter than the stock one.
I will give the "power scale" within the phase inverter a try and see how it sounds and brings down volume; I expect it to become a little bit more treble sounding, so high frequencies need to be attenuated when using "power scale".
Hopefully I can do some videos this evening.
Regards, Dietmar
EDIT: by calculation a 10 meg resistor before the mv pot would reduce the volume to the desired amount (as it was before) ...
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Hi Nigel
Calculating a little bit around with a stock mv preamp and that modded one (1µF across 10k resistor and 680nF across 820 (1k)) ... and it shows, that the modded version gives around 12 to 15dB more output (in practice) to the phase inverter than the stock one.
I will give the "power scale" within the phase inverter a try and see how it sounds and brings down volume; I expect it to become a little bit more treble sounding, so high frequencies need to be attenuated when using "power scale".
Hopefully I can do some videos this evening.
Regards, Dietmar
EDIT: by calculation a 10 meg resistor before the mv pot would reduce the volume to the desired amount (as it was before) ...
Hi stone, I was just playing mine amp today & it is a lot louder. What type of power scaling do you use? Wonder what would happen if you put a 10meg there? never tried that before. Looking forward to hear how your amp sounds.
I have also a #36 mod if you’re interested.
Cheers :)
Nigel
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Hm ... not satisfied with it, but gives an impression: http://www.youtube.com/watch?v=XoK-pOUM0t8
Added the power scaling as a potentiometer to the cathodes of the PI (added to the 470 ohms resistor) and I have to say, it works better than expected - I need to adjust it, because it adds a little bit saturation to the sound, but basically it is working very well.
At least I think most of the sound is generated while driving the PI that hard ...
Still left out the bright cap on the 470k/470k voltage divider.
Regards, Stone
EDIT: what I need to add - my guitar is tuned half step down ... and the 150k on gain is not active
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Hi stone, sounds real good & still got the good old Marshall flavor :) What's your opinion? Could you tell me a bit more about the power scaling, where did you put the poti & what size is it.
Cheers :)
Nigel
ps i don't use the 150k
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Hi Nigel
http://mirror.stones-amp-inn.de/marshallamps/jcm800_lead_mstvol_100w_2203.pdf
If you refer to that schem, I "replaced" R16 at the PI with 47k potentiometer (linear type) - as I could not lift up the circuit board I disconnected the wire from the tube socket which goes to cathodes of V3 and inserted the potentiometer. The recording was done with potentiometer set to half, so the total resistance for R16 would have been around 20k to 25k.
I think the overall sound of the amp is ok - with potentiometer set to "0" it is a real killer, but even too loud. So next time I will do a recording with a power soak in order to get the PI driven hard as before.
While simulating the "power scale" with LTSpice I can see that the high frequencies are not attenuated as they are without - so I think I can recreate most of the original (killing loud) sound by adding anode bypass caps; simulation shows that 500pF across the 100k will be a step in the right direction (have to calculate the value for 82k anode).
At least I must say I am a little bit more satisfied with the fat crunch sound I had before, but that also depends on personal taste. Maybe using another guitar with a straight DiMarzio PAF on it will give a more common example.
Regards, Stone
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btw would be nice to see the version of your SIR #36 mod :)
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Yes, show it to all of us !!
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Hi stone, thanks for the info.
Ok here is the mod
#36 mod
Stage 1 input 33k shield to ground. Cathode 2k7/0.68uf/ coupling cap 0.022uf/ 470k/500pf 1meg a pot/ 1000pf bright cap silver mica.
Stage 2 Shield on anode. Cathode 10k/.1uf/ coupling cap 0.022uf/ 500pf over the 100k plate resistor. 470k/500pf/470k.
Stage 3 Cathode 10k coupling cap 0.022uf 100k plate resistor. 470k/500pf/470k.
Stage 4 Cathode 820r/0.68uf.
Tone stack 33k/250pf the rest stock.
100pf fizz cap
NFB 47k/0.47uf /4ohm tap.
Stock power amp
Make sure that the shield is on anode or it will not work.
It will be just one big hiss oscillation machine
I think that’s all
Cheers :)
Nigel
PS try this if you only know what you are doing.
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Hi Nigel
Ok, it seems to be a #39 without switching option(s). I have already done a #39 based conversion on basis of my 2203.
I think, I will make schems for them mods and post them.
Regards, Stone
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Hi Nigel
Ok, it seems to be a #39 without switching option(s). I have already done a #39 based conversion on basis of my 2203.
I think, I will make schems for them mods and post them.
Regards, Stone
Hi stone, its more or less the same, I have found that, that circuit is very sensitive & any type of switching changes the tone. That would great if you would do a schem for them both :). Oh yes all the coupling caps are 0.022uf. How did your #39 work out?
Cheers :)
Nigel
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Hi
Changed it a little bit - it is documented here in the Marshall section (have a look for "Neues Projekt SIR #39" somewhat of darkbluemurder).
A video is also uploaded here http://www.youtube.com/user/StoneAmplification#p/u/1/PqH4DfUdjyw
The initial stage is taken off a SLO100 and currently I have added something like a tube booster with the left triode. Will do some recording of the acutal setup next days.
Regards, Stone
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Hi
Changed it a little bit - it is documented here in the Marshall section (have a look for "Neues Projekt SIR #39" somewhat of darkbluemurder).
A video is also uploaded here http://www.youtube.com/user/StoneAmplification#p/u/1/PqH4DfUdjyw
The initial stage is taken off a SLO100 and currently I have added something like a tube booster with the left triode. Will do some recording of the acutal setup next days.
Regards, Stone
Hi stone, sounds good, what do you think of the greenback speakers? I was using 4x12 scumback m75 65w speakers, but found them to be too bassy. I have changed to celestion g12h30 heritage & find them to be the speaker I was always looking for.
Cheers
Nigel
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Hi Nigel
The cab belongs to mac_alex_2203 and was used during the TT meeting we had in mid of September - as Marc told me, he is using beam blockers in order to get rid of the ear piercing and scratchy highs of the Greenbacks. I was impressed by the beam blockers because normally I find the Greenbacks way to high sounding.
My personal favorite combination is what I have used for the last 7 or 8 years: it is one cab loaded with Celestion G12K and the other one with them Craaft speakers; I recently changed the Craaft cab and it has now two Celestion V30 and two of them Craafts.
The V30s itself are a little bit scratchy and do lack some bass to my ears if they are used as a quartet.
Regards, Stone
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Good morning,
the cab is a 1960AX with two GBs and two V30 mounted as 'X'. The both top speakers have beam blockers, the bottom speakers not.
Yours,
Marc
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#36 mod first mod to 2203/2204
Stage 1 input 33k shield on anode. Cathode 2k7/0.68uf. 470k/500pf 1meg a pot/ 1000pf bright cap silver mica
Stage 2 Shield on anode. Cathode 10k/.1uf 470k/500pf/470k. 500pf over the 100k plate resistor
Stage 3 Shield on anode. Cathode 10k/.1uf 470k/500pf/470k. 500pf over the 100k plate resistor
Stage 4 Cathode 820r/0.47uf. Tone stack 33k/250pf the rest stock
100pf fizz cap
NFB 100k/0.1uf
Make sure that the shield is on anode or it will not work.
It will be just one big hiss oscillation machine
Hi Nigel,
Many thanks for summarizing the #36 mod - these are the specs as I understood them from the various posts in the Metroamp forum. I have not tried them personally but that should definitely be much more gainy and have more midrange than the #39 version I tried. And indeed - I did not have any plate caps or plate shields and it was very noisy when I added cathode bypass caps to the 10k resistors.
BTW I moved on from my #39 conversion and changed some of the parts.
Stage 1: input 33k, shielded cable, Rk 2k7, Ck 0.68uf, Ra 100k, Ca 220pf, 22nf coupling cap, 1 Meg II 680pf into 1MA gain w/ 1000pf bright cap
Stage 2: Rk 1k5, Ck 1uf, Ra 100k, voltage divider 470k into 470k II 220pf,
Stage 3: Rk 10k, no Ck, Ra 100k, 470k into 220nf then 470k to ground
Stage 4: Rk 1k, no Ck, Ra 100k
Stage 5: standard Marshall cathode follower
Tone Stack: slope 56k, treble 250pf/220kB, bass 47nf/1MA, mid 22nf, 25kB
Power amp: standard Marshall Bass amp, 100pf fizz cap, 47k/8 ohms NFB, 0.68uf presence cap. I may change the NFB to 100k/8 ohms and the presence cap to 0.1uf.
Cheers Stephan
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Hi Nigel
The cab belongs to mac_alex_2203 and was used during the TT meeting we had in mid of September - as Marc told me, he is using beam blockers in order to get rid of the ear piercing and scratchy highs of the Greenbacks. I was impressed by the beam blockers because normally I find the Greenbacks way to high sounding.
My personal favorite combination is what I have used for the last 7 or 8 years: it is one cab loaded with Celestion G12K and the other one with them Craaft speakers; I recently changed the Craaft cab and it has now two Celestion V30 and two of them Craafts.
The V30s itself are a little bit scratchy and do lack some bass to my ears if they are used as a quartet.
Regards, Stone
Hi stone, Cheers thanks for the info :)
Nigel
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Good morning,
the cab is a 1960AX with two GBs and two V30 mounted as 'X'. The both top speakers have beam blockers, the bottom speakers not.
Yours,
Marc
Hi Marc, I was thinking about doing that myself, I have 2 extra g12h30 heritage & a box with 4x12 scumback m75s. I'm going to swap 2 out & replace them with the g12h30s see how it sounds.
Cheers :)
Nigel
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Hi Nigel,
Many thanks for summarizing the #36 mod - these are the specs as I understood them from the various posts in the Metroamp forum. I have not tried them personally but that should definitely be much more gainy and have more midrange than the #39 version I tried. And indeed - I did not have any plate caps or plate shields and it was very noisy when I added cathode bypass caps to the 10k resistors.
BTW I moved on from my #39 conversion and changed some of the parts.
Stage 1: input 33k, shielded cable, Rk 2k7, Ck 0.68uf, Ra 100k, Ca 220pf, 22nf coupling cap, 1 Meg II 680pf into 1MA gain w/ 1000pf bright cap
Stage 2: Rk 1k5, Ck 1uf, Ra 100k, voltage divider 470k into 470k II 220pf,
Stage 3: Rk 10k, no Ck, Ra 100k, 470k into 220nf then 470k to ground
Stage 4: Rk 1k, no Ck, Ra 100k
Stage 5: standard Marshall cathode follower
Tone Stack: slope 56k, treble 250pf/220kB, bass 47nf/1MA, mid 22nf, 25kB
Power amp: standard Marshall Bass amp, 100pf fizz cap, 47k/8 ohms NFB, 0.68uf presence cap. I may change the NFB to 100k/8 ohms and the presence cap to 0.1uf.
Cheers Stephan
Hi Stephan, thanks for the info, here is a link to a Caswell modded amp, maybe you guys would like to analyse it & draw up a schem.
link http://picasaweb.google.com/Stratocaster64/Plexi02?authkey=Gv1sRgCNi9_dnO2oj2Vw#
I think someone said it was 1 of George lynch's amps. Looks very like a #39 mod.
Cheers :)
Nigel
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Well, the interesting thing is that my Splawn-style modded 100 watter sounds a lot closer to Dokken/Lynch Mob than my #39 mod ever could. The #39 was just clear, clearer, clearest.
Cheers Stephan
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Well, the interesting thing is that my Splawn-style modded 100 watter sounds a lot closer to Dokken/Lynch Mob than my #39 mod ever could. The #39 was just clear, clearer, clearest.
Cheers Stephan
Hi Stephen, have you any clips of your amp?
Cheers :)
Nigel
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Hi Nigel,
Unfortunately I am not set up for clips. I do not have any recording equipment.
Cheers Stephan
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Hi Nigel,
Unfortunately I am not set up for clips. I do not have any recording equipment.
Cheers Stephan
Hi Stephan, ok
Cheers
Nigel
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Hi Nigel
Tried another recording and uploaded it to YT http://www.youtube.com/watch?v=GDpoiYWk22s - it comes a little bit closer than the other one.
Regards, Stone
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Hi Nigel
Tried another recording and uploaded it to YT http://www.youtube.com/watch?v=GDpoiYWk22s - it comes a little bit closer than the other one.
Regards, Stone
enotS iH
tleW etrhekrev
nehcoJ eßürG
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Stimmt ...
http://www.youtube.com/watch?v=HYlwi4Le4TI&feature=mfu_in_order&list=UL
Danke, Stone
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Stimmt ...
http://www.youtube.com/watch?v=HYlwi4Le4TI&feature=mfu_in_order&list=UL
Danke, Stone
Aaah
klingt doch gleich ganz anders , gell
Grüße
Jochen
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Hi stone, sounds good, what differences have you made?
Cheers
Nigel
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Hi Nigel
No differences to the first recording, except that I connect the Sennheiser mic to mic input of my laptop and so I can lower the level; I am using a TTpro power soak ;) And the PI is driven hard (removed the power scaling potentiometer).
There is still some hiss on top of the sound, which is unfortunately added by the laptop or whatever :(
Regards, Stone
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Hi stone, have you made any changes to the amp?
Cheers
Nigel
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Hi Nigel
Hi stone, have you made any changes to the amp?
Cheers
Nigel
No, not to the circuit - I removed the power scaling pot, that 's all.
Regards, Stone
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Hi, stone, could you please tell me a bit about your power soak, can you use it also with 100w amps?
cheers
Nigel
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Hi Nigel
It is one of Dirks attenuators - most of the information including schems can be found here: http://www.tube-town.net/diy/tt-pos/tt-posx-de.html - I have got the 200 watts version (TT PoS200 Pro). I built it a few months ago for a friend of mine, but he changed the amp and gave it back to me.
At least I find the treble "correction" pretty useful while attenuating signals to a very low level. The overall performance is pretty good, at least in relation to the price of DIY kits of them. Refering to calculations I have done on their resistance they do not react exactly like a speaker, but resistance increases with input frequency which is close to the behaviour of a speaker.
I think Aiken has a more complex model, but which is a power soak / load box and which behaves like a guitar speaker - I tried to build it years ago but was not able to get most of the parts, so I left it.
Overall I would recommend Dirks attenuators before spending around 300 to 400 euros for a THD or Scholz.
Regards, Stone
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Hi stone, thanks for answering. I was looking at that model, but the only thing is its 8ohm, what do you do with your 16ohm box?
Cheers
Nigel
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Hi Nigel
According to Dirks documentation it is designed for 8 and 16 ohm loads (speakers) - the input impedance is around 8 ohms (for the amp); I measured 7,2 ohms at input.
Regards, Stone
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Hi stone, thanks for the info.
Cheers
Nigel
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Hi Guys, found this mod on the net. http://img263.imageshack.us/img263/9439/36mod.jpg
What do you think?
Cheers
Nigel
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Hi Nigel
I am not sure if this is a #36 layout, it seems to be a mod / variation of the #36 modification - but it is interesting. The first thing I had in mind while seeing this was the layout of the London 4-stage preamp as described in one of the TUT books.
Having a closer look it is basically a "reversed" 220x layout (10k triode at first followed by 2k7 triode): the first triode acts as a tube booster and the cathode follower is rewired to a anode follower with tone stack.
What I am missing is a coupling cap between anode of V2b and 33k slope resistor - on the one hand side it is not really needed because of the voltages of the tone caps usually, on the other hand side it adds a little extra safety.
Regards, Stone
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Hi stone, thanks for answering. On another forum someone said it was from the Kevin O’Connor’s 4 gain stage Marshall Mod, from the TUT books, & also very similar to the Roccafortes HG100.
I think I will give it a try & see what comes out.
Cheers :)
Nigel
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Hi Nigel
Yes, Kevin O'Connor is the man of London (Power Amps). It is right, basically - with a few changes - it is the Kevin O'Connor 4-stage preamp option mentioned within TUT volume 2 (I think) ...
It should sound a little bit harder than a stock #36 mod, because of the 1k5 resistor at the last cathode - the 10k system in front of the whole preamp acts like a tube booster which will give you more drive / saturation to the tone.
I have tried something similar with my #39 mod and it is pretty good for soloing and rythmn tones - latter ones if you are backing your guitar volume.
Regards, Stone
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Hi stone, Just tried that mod, its really highgain. Sounds ok just a bit too bassy, I will tweak it a bit & see what happens.
cheers
Nigel
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Hi stone, got the bass sorted out, it was a B1M pot that i had use because i didn't any A1M pots, changed that & the amp sounds ok.
Cheers
Nigel
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Hi Nigel
Try a second 1M or 500k potentiometer instead of 68k / 680k voltage divider ;-) This will come close to what I have done many times and you are able to adjust the "shape" of distortion and not only the tone.
Regards, Stone
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Hi stone, just tried that & it sounds good, only had a B500k pot, would you also leave the 68k out? Just have to get some mids, sounds a bit too scooped, i think i will lower that 1000pf see what happens. With that mod the amp is not as loud as the #34 mod which is better, you don't have to use a power soak.
Cheers
Nigel
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Hi Nigel
Thanks for the info - I am thinking it over to give it a try and it seems to be worth it.
Regards, Stone
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Hi stone, no problem, just tweaking it a bit myself. Changed the 2k7 over so that it come first & then the 10k, sounds a bit more open, before the 500k pot i have put a 470k/500pf. Might put a bright cap on that 500k pot.
Cheers
Nigel
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Hi stone, I have took the 470k/500pf out didn't like it. It would be nice if you also tried the mod, then we could both compare our results.
Cheers
Nigel
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Hi Nigel
Sorry for answering late - maybe I have a chance to do some recordings and mods this week; got a new idea for better quality recordings and will have a look if it works.
Regards, Stone
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Hi Nigel
Sorry for answering late - maybe I have a chance to do some recordings and mods this week; got a new idea for better quality recordings and will have a look if it works.
Regards, Stone
Hi stone, no problem, looking forward to your results.
cheers :)
Nigel
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Hi Stone,
I am glad to see, that you are back in business again.
Tweak on!
Best regards
Holgar
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Hello
Thanks, Holgar :)
@Nigel: sorry, but currently I do not find any time going on and still I do not have done any further recordings. I think it will last some more weeks until working on tube amp circuitry again :(
Regards, Stone
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Here's a 50 Watter I've modded lately - it was completely modded by Finkenhäuser long before (+ clean channel, + loop, + anode-follower-4stages).
The clean and loop are very cool and well made IMO, the 2nd channel just had a bit too much of everything and lacked some dynamics, a pure lead channel, not a heavy cruncher, so . . . .
I've built that back into 3+CF with "my stuff" and a (soft) depth - I was trying to get back the typical Marshall flair, but with more bottom end and a more modern, meaty gain structure.
The clean channel recording hisses - was my fault, the mic pre had the HiZ setting . . .
http://www.youtube.com/watch?v=CcayuqKpI_Q
Input-R: 1K
150k Plate/1k5,2µ2 Cathode/4n7 - 470k+150pF - Gainpot (250klog)
100k Plate/2k7 Cathode/4n7 - 470k/470pF/470k(g)
100k Plate/820R Cathode
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Hi Olaf
Sounds good. Interesting detail: I found a 2µF (yes I know you are using 2µ2) across a 1k5 in combination with 150k plate very suitable for an amp of a friend of mine ... it is pretty close to your mod as I have used a 22nF between stage 1 and 2 and used a 2n2 between stage 2 and 3.
From my point of view this adds a bit more meat to the solo sound / lines but the overall sound is a bit more compressed then.
Regards, Stone
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Not if you keep the coupling caps' values low and the gain pot's value lower than 500k, Stone ;)
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Olaf,
I know, but the aim was to have a certain amount of compression ;) So I decided to use that big one as first coupling cap ... :) ... and to keep the other values, too (e.g 1M gain).
Regards, Stone
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hi,
@ olaf: what values did you use for your "soft depth"?
btw. very interesting thread... again :bier:
best regards,
tobi
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A 4n7 and just a 250k log pot, gives much better (finer) results and makes it easy to add just small amounts of these 100Hz (or so).
-
Olaf,
concerning depth ... do you remember how much it was dialed in during recording? I know about its function and did use it on 4x00 Marshalls, but I never needed it with the older MVs oder SLPs because I think they 've got enough punch and bottom even with high gain "enabled".
Meanwhile I own a SLO100 clone and the added depth mod on that amp does make pretty much sense, which I did not expect to be necessary, but it is.
Regards, Stone
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Kann es mal sein, dass die ganzen SIR -Schaltungen ein wenig wie die Laney´s aussehen (GH-Serie mit den 4 Stufen vor dem Kathodenfolgerfür 36/39 und LC-Serie mit der 2203/4-typologie für den #34)?
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Hi
Ja, ist richtig.
Die Frage ist halt, wer da bei wem abgeschaut hat - allerdings kommt man ja automatisch in die Verlegenheit, mehrere Stufen zu kaskadieren, wenn man "high gain" will ;)
Mein Laney GH50L hat auf jeden Fall ziemlich gut geklungen - ich ärgere mich auch, den verkauft zu haben. Ab einem gewissen Grad des gain Poti hat er allerdings "übersteuert" / gepfiffen.
Gruß, Stone
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Tach stone,
mir ging es aber auch vor allem um die Beschaltung der Vorstufen. So findet sich bei einigen Laneys 2k7II680uF an den ersten beiden Kathoden bevor es auf die "kalte" 10k-Stfe geht. Auch die Gridstopper vor der 2.ten (und 3.ten -je nach Modell) hatten/haben die Laney´s. Und das zum Teil schon seit 1984 (!!!). Ich könnte mir vorstellen, dass die uU die Vorreiter waren.
Und die Verkleinerung des seriellen widerstandes vor dem Gain auf 220k und das weglassen des entsprechenden peaker-caps sowie der "gesplittete Kathodenwiderstand" an der zweiten Stufe bei Teilen der LC-Serie errinnern mich dann an den #34. Wer hats erfunden ? -die sparsamen Schweitzer evtl.
Grüße,
snyder80
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Hi Snyder
Ja, das hatte ich mir schon gedacht. Die 2k7-Systeme bei den Laneys sind schon auffallend - die Kaskadierung von insgesamt vier Stufen kommt bei Laney schon aber im Klipp 100 vor und der ist Ende der 60er, Anfang der 70er aufgetaucht, meine ich.
Das Teil - ich hatte mal einen - klingt aber ein wenig fuzzy, für die Zeit aber durchaus üblich.
Auf die Rechnung von Marshall würde ich das 10k-System setzen, welches aus meiner Sicht für einen nicht unerheblichen Anteil Crunch sorgt.
Gruß, Stone
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Hey Guys, here is a clip from my amp after a bit more tweaking :)
http://soundclick.com/share.cfm?id=10357831
cheers
Nigel
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Hi Nigel
I haven't been working on mods again since months, but have listened to your AFD 274 - would you like to share the schem again?
Regards, Stone
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Hi Nigel
I haven't been working on mods again since months, but have listened to your AFD 274 - would you like to share the schem again?
Regards, Stone
Hi stone, sorry not posting anymore schem, too much hastle with people not knowing how to do them right.
Cheers
Nigel
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Hey Nigel,
sad to hear that. Beside all information at metroamp, your schematics were the basis for the #34 conversion of my Linnemann-SLP. Is it becauce of the shield trick?
I follow the #36 thread at metroamp since around page 60 and I am curious to try it by myself, but first I need more time and an adequate amp for modding. I am thinking if building another SLP as a starting point for the #36, but I don't think I can get so far before summer... :(
Cheers,
Kilian
PS: Damn, reading English is so much easier than writing... :D
PPS: Wow, your 274 version is GREAT! Haven't heared it before. Is it still with EL34 and Greenbacks?
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Hey Nigel,
sad to hear that. Beside all information at metroamp, your schematics were the basis for the #34 conversion of my Linnemann-SLP. Is it becauce of the shield trick?
I follow the #36 thread at metroamp since around page 60 and I am curious to try it by myself, but first I need more time and an adequate amp for modding. I am thinking if building another SLP as a starting point for the #36, but I don't think I can get so far before summer... :(
Cheers,
Kilian
PS: Damn, reading English is so much easier than writing... :D
PPS: Wow, your 274 version is GREAT! Haven't heared it before. Is it still with EL34 and Greenbacks?
Hey wholelottanoise, glad you like it, its with el34s & g12h30 heritage speakers, if you need help send me an email, but i dont want to post anymore schem.
cheers
Nigel
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Hi Guys, here is some new clips with different specs im trying out.
http://www.soundclick.com/bands/default.cfm?bandID=1032010
cheers :)
Nigel
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Hey Nigel,
thanks for your offer! I'm sure I'm gonna have many questions when I start my project ;D
Cheers,
Kilian
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Hey Nigel,
thanks for your offer! I'm sure I'm gonna have many questions when I start my project ;D
Cheers,
Kilian
no problem :)
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Hi Nigel
No problem - I respect your decision as I know what you are talking about.
Regards, Stone
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Hi Nigel
No problem - I respect your decision as I know what you are talking about.
Regards, Stone
Thanks for understanding :)
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Hey ho,
I couldn't get this mod out of my head and that reminded me of an old modded London City DEAxxx I bought at the Musik Produktiv Flohmarkt years ago. For those who don't know it: It is a 100W Marshall clone with a JTM45 preamp. It didn't work properly and I always wanted to fix it. That's my chance :P
Well, I opened it, was shocked of its inner condition and startet ripping out everything that wasn't original. Then I converted the power amp to 1959 and now I have some kind of basis for my own #36 ;D
I'm gonna keep you up-to-date, when I have first results.
Cheers
Kilian
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Hey ho,
I couldn't get this mod out of my head and that reminded me of an old modded London City DEAxxx I bought at the Musik Produktiv Flohmarkt years ago. For those who don't know it: It is a 100W Marshall clone with a JTM45 preamp. It didn't work properly and I always wanted to fix it. That's my chance :P
Well, I opened it, was shocked of its inner condition and startet ripping out everything that wasn't original. Then I converted the power amp to 1959 and now I have some kind of basis for my own #36 ;D
I'm gonna keep you up-to-date, when I have first results.
Cheers
Kilian
have you any pics of the amp? :)
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Here you are. This was before I changed anything. Now it has less messy wires, preamp and poweramp like SLP, new pots, new filter caps and a nice 20mm hole for an additional ECC83.
Next to do:
- THAT DAMN GREEN/YELLOW CABLE ::)
- change switches for power and standby
EDIT: There are some components an the back of the board, like PI caps and the second pair of diodes in the power supply. Couldn't make photos of that.
-
Here you are. This was before I changed anything. Now it has less messy wires, preamp and poweramp like SLP, new pots, new filter caps and a nice 20mm hole for an additional ECC83.
Next to do:
- THAT DAMN GREEN/YELLOW CABLE ::)
- change switches for power and standby
EDIT: There are some components an the back of the board, like PI caps and the second pair of diodes in the power supply. Couldn't make photos of that.
nice amp that should work good for a #36 amp :)
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Hi Guys, here is a new clip with more tweaking, :laugh:
http://soundclick.com/share.cfm?id=10372383
cheers
Nigel
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Hey Nigel,
though I think your versions 272 and 274 sound closer to AFD, I would prefer the new one. Sounds thicker and less compressed to me. Just great :danke:
Cheers,
Kilian
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Hey Nigel,
though I think your versions 272 and 274 sound closer to AFD, I would prefer the new one. Sounds thicker and less compressed to me. Just great :danke:
Cheers,
Kilian
yes the 272 & 274 probably sounds more like it would sound after studio & mastering processing, & the new clip is the way you would want your amp for live, big Marshall growl :laugh:
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Hey guys,
today, I made my first try for #36. After some tries and reading again the last few pages of the SIR-thread at metroamp (most valuable information came from the short discussion between dukeamps and tschrama - thank you).
I used the "save" way of shield trick and a 470p at second anode. So far, no humming, no squeeling, surprise! :o Only with dimed gain pots I get blocking distortion. I might put some grid stoppers in but since I won't dime them usually... ::)
This amp really rocks! I was just able to dial the master to about 1 but even with this low volume it had everything I didn't know i was missing with the #34 ;D It was fat and crunchy and loud (!) - but it didn't sound so much like AFD. Finally, I added a switch for a .1 cap parallel to the 10k at second cathode and now I think I am quite near. For chords and riffing it sounds best for me without the .1, but for solos with the neck humbucker I really like this cap!
Later, I will test the amp in band context. That's gonna be fun... :devil:
Cheers,
Kilian
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Hi Kilian
A bypass cap on the last cathode before cathode follower generates a lot of punch and volume. So, adding a bypass cap across the 820 ohms (sometimes 1k) within Marshall will drive the cathode follower harder (and so the PI).
Regards, Stone
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A bypass cap on the last cathode before cathode follower generates a lot of punch and volume. So, adding a bypass cap across the 820 ohms (sometimes 1k) within Marshall will drive the cathode follower harder (and so the PI).
Hey Stone,
yepp, I'm gonna try that tomorrow. But I don't think I will need any more punch ;D
Cheers,
Kilian
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Hey guys,
today, I made my first try for #36. After some tries and reading again the last few pages of the SIR-thread at metroamp (most valuable information came from the short discussion between dukeamps and tschrama - thank you).
I used the "save" way of shield trick and a 470p at second anode. So far, no humming, no squeeling, surprise! :o Only with dimed gain pots I get blocking distortion. I might put some grid stoppers in but since I won't dime them usually... ::)
This amp really rocks! I was just able to dial the master to about 1 but even with this low volume it had everything I didn't know i was missing with the #34 ;D It was fat and crunchy and loud (!) - but it didn't sound so much like AFD. Finally, I added a switch for a .1 cap parallel to the 10k at second cathode and now I think I am quite near. For chords and riffing it sounds best for me without the .1, but for solos with the neck humbucker I really like this cap!
Later, I will test the amp in band context. That's gonna be fun... :devil:
Cheers,
Kilian
try these settings g1 7, g2 6, mv4, t6, m4, b4, p6,
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Hey ho,
yesterday, I heard the amp in band context for the first time and... well... I think it's already perfect. ;D
Even my band liked it, though usually nobody really cares when I bring something new/different.
But it wouldn't be me if I didn't try to tweak it anymore... ::)
Cheers,
Kilian
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Hey ho,
yesterday, I heard the amp in band context for the first time and... well... I think it's already perfect. ;D
Even my band liked it, though usually nobody really cares when I bring something new/different.
But it wouldn't be me if I didn't try to tweak it anymore... ::)
Cheers,
Kilian
could you post a clip please :)
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Hello
It 's a pain in the ass, as everytime I promise myself to re-start my work on tweaking amps, my workload is increased by my customer :( I hope to have a chance on weekend.
Nigel: I got your info - thanks for that and sorry for delaying a comparison again.
Regards, Stone
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Hello
It 's a pain in the ass, as everytime I promise myself to re-start my work on tweaking amps, my workload is increased by my customer :( I hope to have a chance on weekend.
Nigel: I got your info - thanks for that and sorry for delaying a comparison again.
Regards, Stone
Ok, looking forward to hearing your clips :)
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could you post a clip please :)
I'm gonna try it next week. Or maybe later today at low volume.
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I'm gonna try it next week. Or maybe later today at low volume.
ok
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Here we go! Sorry for my sloppy playing! :P
http://www.skillwax.de/stuff/LondonCity.mp3 (http://www.skillwax.de/stuff/LondonCity.mp3)
Settings: G1 5 - G2 7 - B 4 - M 7 - T 6 - P 7 - Master << 1 (bedroom level)
Edwards Les Paul w/ Duncan AlNiCo Pro -> Amp -> Marshall 1936 w/ V30 & T75 -> SM57 on axis of V30 -> Interface -> Kristal.
Cheers,
Kilian
PS: I just realized my cheap wireless headphones I recorded with took away MANY of the high freqencies. Now, with my others it sounds totally different and I can even hear my guitar in the background. Crap! >:(
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Here we go! Sorry for my sloppy playing! :P
http://www.skillwax.de/stuff/LondonCity.mp3 (http://www.skillwax.de/stuff/LondonCity.mp3)
Settings: G1 5 - G2 7 - B 4 - M 7 - T 6 - P 7 - Master << 1 (bedroom level)
Edwards Les Paul w/ Duncan AlNiCo Pro -> Amp -> Marshall 1936 w/ V30 & T75 -> SM57 on axis of V30 -> Interface -> Kristal.
Cheers,
Kilian
PS: I just realized my cheap wireless headphones I recorded with took away MANY of the high freqencies. Now, with my others it sounds totally different and I can even hear my guitar in the background. Crap! >:(
it would be nice to hear it with the master at 4, but you can hear the vibe :)
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Just coming back from rehearsel, but even there I couldn't crank the master past 2 ;D