Zitat von: Grimlock am Aug 20, 2008, 11:24
Hello Cliff,

you've attached the mass to the centertaps of the noval sockets. joachim did not (accept voor V1 and V2 i think in the end) (sorry for comparing you both all the time. I hope this doesn't offend any of you both?). After completing your amp ... did it seems a reasonable thing to do? or didn't it really make a difference?

I've read in joachims topic that "Das auf Masse legen der Schirmkontakte von V1 und V2 bringt zwar keine so deutliche Verbesserung". Does the fac that V1 and V2 are DC heated were as V3-V5 are AC heated, make any difference?

further more (that might be a little off topic) but could someone translate "Isolieren der Buchsen ". I have a feeling that it's seperating the input/footswitch/send/return/speaker-"things" (I don't even know what it's called in dutch->phone jacks according to my order from mouser)from the chassis, but I'm not sure?

kind regards
Dimitri

I did that to prevent hum. In fact I don't exactly know if it works.
I've read some post where somebody mentioned that it would better to put the centertabs to the ground.

Joachims V1 and V2 are dc heated. I guess there will be no more chance for hum. The other valves are not so critical.

Me and Joachim use washers for the jacks. In your case i would use this ones, if you want to use switchcraft jacks:
http://www.tube-town.net/ttstore/product_info.php/info/p2012_Switchcraft-S1028-Iso-Scheibe---Benoetigt-S1029.html
http://www.tube-town.net/ttstore/product_info.php/info/p2011_Switchcraft-S1029-Kragen-Scheibe---Benoetigt-S1028.html


Greetz Cliff

Hi Dimitri,

I made the ground connection at V1 and V2 as I heard a (little) difference here. During my tests with the other preamp sockets I heard definitively no difference in noise and hum, so I decided to ground only V1 and V2 sockets. However it won't do any harm if you connect the center pins of V3, V4 and V5 to ground. I think the main reason for that behaviour is that V1 and V2 have much more gain than the other tubes ...

ZitatIn fact I don't exactly know if it works.

... me neither

Cheers!
Joachim

Hellow

@ cliff: I've allready isolated them from the chassis. no special washers, just a basic DIY method. I would take a picture and show it...but certain things are better to remail a mystery . I've measured it trough and there is no connection to the chassis...that's what matters

@ joachim: and I thought you were all electronic-experts (just kidding )

So if I can't make any mistakes by doing that, I think I'll just do it. every little thing could help to reduce the humming...

thank you!
Dimitri

Zitat von: Grimlock am Aug 20, 2008, 12:28
@ joachim: and I thought you were all electronic-experts (just kidding )

:devil:

Zitat von: Joachim am Aug 20, 2008, 12:35
:devil:

just some good clean fun  :angel:

good night
Dimi