Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Matty_V on September 14, 2011, 10:20:17 pm

Title: wiring paralleled triodes
Post by: Matty_V on September 14, 2011, 10:20:17 pm
How do you run the wiring for a parallel triode? You've got 3 wires crossing paths, whats the best way to route them? I've got a beastly parasite to tame and might as well start here (the start!)

Danke
Title: Re: wiring paralleled triodes
Post by: HotBluePlates on September 14, 2011, 11:12:21 pm
Three short wires connecting the pins directly placed on the socket itself.

Pin 3 to pin 8, pin 2 to pin 7, pin 1 to pin 6.

This is the same manner in which the paralleled triodes of a reverb driver are wired.
Title: Re: wiring paralleled triodes
Post by: stingray_65 on September 14, 2011, 11:14:12 pm
Hey Matty,

Beastly!?

is it a Push Pull power section?

may need to swap the plate lead on the OT.

Have you chopsticked the leads in your suspect area and have noticed a difference better or worse?

I've paralleled a few triodes, even had one that switched in and out in a high gain, but haven't had oscillations (that I know of).

Ray

Title: Re: wiring paralleled triodes
Post by: Matty_V on September 15, 2011, 01:00:53 am
Oh ok, I took a look at dougs picture of the reverb stout to check out how its done. I guess I was making too big of deal of keeping the grid wire up above the plate and cathode. The way I had it was making the grid wire into an antenna for noise.

It starts its vampire hissing around 1/2 up on the volume. Not sure why I haven't tried switching the plate leads yet. Maybe cause last time I had them swapped it wailed mercilessly right as it was turned on. How come one configuration causes such awful oscillations?
Title: Re: wiring paralleled triodes
Post by: TIMBO on September 15, 2011, 01:28:38 am
Hi Matty V, This is how i did it, kept the heater wire low with the plate wire over, then arched the cathode last.i used two grid resistors and each has its own 1M to ground. Thanks