Oscillation and Trainwrecks on "10"

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10thTx
Posts: 1872
Joined: Sat Dec 30, 2006 1:13 am

Oscillation and Trainwrecks on "10"

Post by 10thTx »

I am curious, on your Trainwreck amps, can you dial everything to "10" and typically NOT have oscillation?

I built a low watt high gain amp (not Trainwreck) and I can dial the volume, master volume and PPIMV to 7.5 without oscillation. Meaning all those on 7.5.

I can dial any two of those gain controls to "10" IF I dial the 3rd one to "5". What is your experience with Trainwrecks? I am trying to figure out if this is within normal limits of some high gain amps?

EDIT: : Turns out it was a very microphonic V1 tube (5879) and now I can dime everything.

This amp has a 5879 into a 12A_7 with CF into TS into LTPI using ECL84's/6DX8.

With respect, 10thtx
Last edited by 10thTx on Sun Oct 30, 2011 7:25 pm, edited 2 times in total.
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selloutrr
Posts: 3694
Joined: Sun Oct 14, 2007 2:44 am
Location: Southern California

Re: Oscillation and Trainwrecks on "10"

Post by selloutrr »

in theory the amp should be able to be run full out every potentiometer maxed out. however it has alot to do with the tubes used and the gain structure of said tube. It's not often an amplifier is run with all knobs 100% maxed. it's more of a safety feature, feedback and oscillation are a design flaw in most amplifiers. Unless you are intentionally trying to achive feedback.

If this is in regards to an amp you built. You may need to look at how the stages are passing along gain and lower it to except the the incoming signal.
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My-Co
Posts: 26
Joined: Fri Feb 15, 2008 6:03 am
Location: Queens, NY

Re: Oscillation and Trainwrecks on "10"

Post by My-Co »

Take a good look at the layout of the wires, in the real deal. Everything adds up. The zen of tube amps Ken Fischer
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