Peavey 5150 effect loop bleed

[RobinPlas]

Hello all,

This is my first post after reading and using this forum for a long time. I love it, there a a lot of really helpful posts here! Thanks for that! Anyway, I have two issues I haven't found a solution for. I thought I might get some help here.

I'm using a Peavey 5150 - mark I with EVH signature, I'm loving the sound, but I hate the effect loop. I can't get rid of unwanted dry signal. For instance when using a tuner or volume pedal in the effect loop won't kill the sound completely but some dry signal will bleed through and can be heard.

Is there something that can be done to fix this? I'm new to electronics myself, but I'm more than willing to learn.

Thanks in advance for any advice!

Robin

[Jazz P Bass]

Disconnect your FX from the loop.
Plug a cord into FX Send.
This should disconnect send from return.
You should hear nothing from the amp.
Maybe your pedals are not "killing" the signal afterall.

[km6xz]

The first thing would be to determine just what level of bleed there is. The send and return jacks are normalled, so when no plugs are inserted there is a path bypassing the jacks and 100% dry is present. When plugging in an effect, depending on design of the effect, it can be either an in-line style or parallel type. For versatility many can act as either by having their own summing control for effect/dry when used in in-line mode, or set at 100% wet in the parallel style as used in an Aux return in a console. So, to figure out where the bleed is occuring you have to try an experiment. Plug in a bare(not wired to a cable) 1/4 phone plug into the Return jack. That will open the normalizing switching of the jacks and the amp will have no return signal or direct connection from the preamp section. Find out if there is any bleed. There would probably be some, but 40-50 db down so inaudible in any signal condition. If you can hear preamp signal getting through the output section there is indeed cross talk(the technical term for bleed). There is a good chance however that the effect you normally use is the source of the dry and wet mix. With this test you can determine which side of the signal change to work on, the amp or the effect. I am guessing its the effect.

[RobinPlas]

Thanks for the replies!

I'm using the 5150's pre-amp in the effect loop of the TC Electronic G-system using the four-cable method. The G-system is - in theory - in full bypass mode when using the internal tuner. The only thing the G-system is doing at that point is directing the signal through the internal tuner and keeping the loop open where I connected the 5150 to.

While using it like this, I still hear signal coming through the speakers. It's not very loud, but it's annoyingly there. I'll check the suggestions later this week when I'm at our rehearsals.

Thanks again!

Robin

[Enzo]

There is no break contact in the FX send, only in the return.

Your problem may not be in the amp at all. For now eliminate ALL the stuff you plug into the loop jacks. DO what km suggested, plug something into the FX return to open the circuit from the preamp. Plug the guitar into the regular input jack and play. Now how much of that bleedthrough is left? What we hear then will be the normal crosstalk of this amp.

But also, when you plug into the FX return, don;t just use one end of a cord, because then the other end of that cord becomes an antenna. A great simple thing would be to plug some other guitar into the FX return and dial the volume on that second guitar to zero.



And may I understand that the problem is only this: when you are tuning, you hear some guitar instead of silence. Is that correct? There is no problem at all during normal play?

[RobinPlas]

Yesterday I checked this issue using a jack plug in the FX return. Plugging in directly into the input of the preamp, I'm still getting preamp signal over the speakers. The best way to show you what I hear is watching this short youtube video where someone is using a POD in the FX loop of his 5150. Switching off the POD would, in theory, silence the complete rig. Yet there is still preamp signal coming out of the speaker. What I hear is exactly to what this guy is experiencing:

YouTube - peavey 5150 II channel bleed ?

[RobinPlas]

Anyone any thoughts?

[Jazz P Bass]

When you insert a plug in the return jack, jumper the tip to the ring.
That should effectively kill that input.
If signal is still getting to the output, it is "crosstalk".
How about calling Peavey.
This may be the way it is.