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Technik => Tech-Talk Fender => Thema gestartet von: zoranrataj2000 am 24.12.2009 17:44

Titel: Fender mit ultralinear AU
Beitrag von: zoranrataj2000 am 24.12.2009 17:44

Hi!
First I must write I understant German, but I can not write in German, so can be answer in German.

I have Fender Pro Reverb with ultralinear OT.They sound very bright.It is still original, but with new caps and tubes (preamp Sovtek, power amp NOS National).I need only clean, but with more live and warm.
 I read many mods.Removing negative feedback line and Master volume should much help.How will this change output impendace on speaker (or will not).
 
Change OT is too expencive.Dr.Z have ultralinear OT too, but they sound much better and alive.

Any suggestions?

Thanks,Zoran

Titel: Re:Fender mit ultralinear AU
Beitrag von: dukesupersurf am 26.12.2009 12:52

Hallo,
ich würde mal probieren die Brightcaps über dem 3.3M Widerstand und am Mastervol. zu entfernen.
JJ in der Vorstufe klingen auch wärmer.

tschüß,Thomas

Titel: Re:Fender mit ultralinear AU
Beitrag von: darkbluemurder am 26.12.2009 14:21

Hallo Zoran,

I would try to increase the 820R negative feedback resistor to 5k. That should make the amp sound more alive. If you like the change, increase it further.

The Dr. Z Route 66 has an ultralinear OT but no negative feedback so you may try to disconnect the negative feedback entirely.

I would not yet drop the master volume. But it may be worth to try a PPIMV (post phase inverter master volume). Check any of my threads on my homebrew amps (see signature).

Good luck
Stephan

Titel: Re:Fender mit ultralinear AU
Beitrag von: zoranrataj2000 am 28.12.2009 21:44

Hi!
Thanks.I will try this at this weekend.I report about results.Thanks.