Hi
I was wondering if there is likely to be trouble when I would dedicate an additional gain stage in an unused triode of the reverb recovery tube. The gain stage is for normal preamp gain structure as in:
V1a 1st stage, V1b cascade stage 2, V4a tonestack driver, V4b reverb recovery
V2a and b are clean channel
V3a and b are reverb amplification
Thx
Preamp tube question
Moderators: pompeiisneaks, Colossal
Re: Preamp tube question
I think that could work ok but ‘God / the Devil is in the detail’ 
Consider that many Fender reverb amps aren’t so different to that.
A possible issue may be that if V4a is being very heavily overdriven, some fizz from that may contaminate the reverb recovery signal. Which may be noticeable at certain combinations of control settings, eg low treble with high reverb.
Consider that many Fender reverb amps aren’t so different to that.
A possible issue may be that if V4a is being very heavily overdriven, some fizz from that may contaminate the reverb recovery signal. Which may be noticeable at certain combinations of control settings, eg low treble with high reverb.
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Re: Preamp tube question
Naah... maybe it's best that I keep that optional then. If it doesn't work out I can always do the 1 tube reverb and use the extra tube for a cathode follower on the lead channel.
Thanks
Thanks
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Stevem
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Re: Preamp tube question
The added gain stages ability to function without oscillating all hinges on the circuit and wiring layout / build!
If the down stream signal flow towards the output stage gets sent back up stream by means of parallel running wires to get to that 1 added gain stage your going to likky have to play around with the build / layout to get it to work right for you.
You will likely need to use shielded wire for the down stream grid runs even if you do the needed right thing with the build which is to make your plate output wires long so that right at the next tube down stream from there is where the uncoupling cap into the next gain stage should go, and all the uncoupling caps need to be tested and installed the right way so that they self shield themselves.
If your build not gone too far already then you might look into fitting the amp with one of the many SS reverbs that can be had these days!
The only down side is since they are SS they do need / eat up more current then a tube.
If the down stream signal flow towards the output stage gets sent back up stream by means of parallel running wires to get to that 1 added gain stage your going to likky have to play around with the build / layout to get it to work right for you.
You will likely need to use shielded wire for the down stream grid runs even if you do the needed right thing with the build which is to make your plate output wires long so that right at the next tube down stream from there is where the uncoupling cap into the next gain stage should go, and all the uncoupling caps need to be tested and installed the right way so that they self shield themselves.
If your build not gone too far already then you might look into fitting the amp with one of the many SS reverbs that can be had these days!
The only down side is since they are SS they do need / eat up more current then a tube.
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Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!