Feedback, presence and resonance....again

 :

2/9/2000 9:59 PM

Nils

Feedback, presence and resonance....again I've built a Bassman 5F6-A clone, well almost   I had only one input so I paralelled the first   triode a'la Chieftain with 100k plate and 1k5   at cathode and bypassed with cap, I used the   bright cap and attenuation grid resistor 270k   I rewired the tone stack D-wise which I think   gave me more control over the sound.   Now I have two questions   The original circuit uses 27k from the 2 ohm   tap and a 5k pot with a 100nF cap, I have   2,4 and 8 ohm taps and use the 8 ohm tap   I tried to solder the feedback to both the 8   and the 2 ohm tap and it squealed a lot, what   values shall I use.   If I instead wanted a Resonance pot what   values then.   I'll post a schematic when I've downloaded   a more fresh version of explorer.   Thanks

 

2/12/2000 4:03 AM
Trace	The feedback you are hooking up should not "squeal" at all. It sounds as though you may have something wired wrong. I would double check the schematic and make you have it wired correctly. Chances are you have simply crossed a wire or two.       Trace

 

2/12/2000 6:54 AM
Carlo	Perhaps you're getting positive feedback. Did you try swapping the wires going to the plates of the output tubes?     Carlo

 

2/12/2000 6:26 PM
jason	I second Carlo on this call. I did the same thing on my first homebrew. Swap the plate leads on the power tubes and your squeal will more than likely go away.   Someone correct me if I'm wrong but I believe you get more feedback from the higher ohm tap (read as, 8 ohm tap will supply more feedback than 2 ohm tap).   Good luck,   jason

 

2/14/2000 7:04 AM
Nils	Thank you all,     Of course you're right, I haven't tried this.     Nils

 

Page 1 of 1