ISP Decimator volume drop?

[onionofdoom]

So today I picked up an ISP Decimator G-String (the original one, not the II.)

Got it for free so I can't complain, seems to do a decent job of eliminating preamp gain-induced hiss. The problem is, using the Decimator in the loop results in a noticeable drop in volume vs having nothing in the loop at all (or any of the other pedals I use, delay etc.)

I have it set up correctly using the guitar input to track the signal, then into the front of the amp, running the send and return in the loop. When I say the volume drops, I don't mean there's a difference between having the ISP engaged and turned off, I mean that simply by being in the signal chain it is reducing the volume coming out of the preamp regardless of whether it is active or not. The active and turned off states do not result in a volume change, but removing it from the loop entirely results in a stronger signal. The volume jump happens when the effects loop is either switched off or just patched through with a cable. I have tried a separate isolated power supply so it doesn't seem to be that either.

The problem is the same with both my Egnater Renegade 65 and my #4 Terror.

Any idea if this is par for the course with the G-string or does it sound like a faulty unit? Am I just being a colossal tool?

Thoughts welcome.

 

[op1e]

Its a loop issue. No matter if its my Peavey Ultra or Randall RM100, putting anything in the loop drops the amp volume unless something else is put in there that has a level control to boost it back up. I bought a TC Spark Booster to remedy this. This is a common thing with amps that don't have level controls for the fx loop. My Marshall doesn't have this problem.

 

[onionofdoom]

The issue is very much with the ISP not the loop. As I said in my original post I don't lose signal with the delay in the loop or any of the other pedals I use. I can jumper the loop with a patch cable and there's no loss of signal at all with either of my amps so it's nothing to do with not having a boost in the loop. The only time it happens is with the Decimator in the signal chain, therefore it can't be the design of the loop on either amp as they work just fine with everything else I use- delay, EQ, chorus etc. I usually run multiple effects in the loop and the only cause of the volume drop is the decimator.

 

[noob_pwn]

it's 100% the loop and whatever other buffers are at play in your system. The decimator does suck a tiny bit of tone but doesn't really affect volume.

 

[onionofdoom]

Not a gripe, but I've already ascertained that it's not the loop as every other pedal I've ever had works fine with the loops on both my amps. You can literally patch across from the send to return of the loop using a cable and there's zero signal loss. I use a delay in the loop constantly, no difference. The problem only exists when the decimator is in the signal chain. Get rid of it, problem is gone. If you need further proof it's not the loop, I've patched it in between the guitar and the amp input and it also drops the signal there whether engaged or not.

 

[Vrollin]

I had two decimators running in my rig a while ago, one after the guitar, one after the preamp in the loop, no tone suck, and definitely no volume drop. I would say theres an issue with the pedal, can you try it with a mates amp or in a store?

 

[4Eyes]

how do you power your decimator? I had similar issue when powered with battery - probably old/ low quality.. using power supply - no problems at all.