What causes a volume drop in some effects and how do you fix it?

[skiraly017]

Two effects off the top pf my head, the EH Small Stone and the Maestro Mini-Phase, both cause a signal volume drop when engaged. What causes that and can it be corrected? Thanks.

[TELEFUNKON]

there mustta been a thread right here somewhere lately IIRC,
but I can`t seem to be able to find it right now.

[markm]

I think the Small Stone layout at TonePad was updated to include the mods to eliminate the volume drop but,
I can't honestly say.
However, there is some info on this within the project page itself + read the build reports there.
   MarkM

[RickL]

Both of these effects were probably designed to work with non-true-bypass spdt stomp switches which typically cause a bit of volume drop in the bypassed position due to the loading of the circuit. The designer probably built a bit of volume drop into the circuit to match the bypassed volume.

[oldrocker]

I'm having the same problem with the Big Muff I just built.  Huge volume drop and I didn't use any bypass circuit at all.  When I turn the amp volume up it sounds good but unlike some other stomps I built this one really kills the loudness.  It might have something to do with the sustain pot problem I'm having which is mimicking the volume pot.  I didn't solve that one yet. 
I haven't seen any other complaints about volume drops on any other message except this one.  Hopefully someone has an answer even if it doesn't fix my situation.

[phaeton]

Can one simply add another transistor stage onto the end of it, or am I just oversimplifying this and being ignorant?

[petemoore]

  that's exactly what I did Phaeton. I have a volume control that goes well above/below unity this way.
  The SS is designed with a volume drop. Because above unity with the circuit as is is going to cause oscillation, the design will bring it to a certain amount below unity, because where that 'falls' exactly isn't exact, it is a product of parts tolerances.
  There are texts about which resistors can be fiddled with to bring it very close to unity. They are either @ Tonepad or GGG.
  I've not viewed or built a Meastro unit you mentioned