Another TimeFactor & Modfactor hum in Egnater Rebel 30 effects loop post

[johnfkiii]

Hi, 

I've looked through the forums, but I could not find an answer to my problem.  I just got an Egnater Rebel 30 (which I love).  I'm running it behind my effects pedal board which has my Modfactor and TimeFactor in series fed separately from the effects loop.  I'm getting significant humming from the pedals, regardless of when their on or off.  The cables are fine, and when I swapped out the MF and TF, the hum went away.   Also, when I ran the series loop in front of the amp, I didn't experience any hum.  I, however, prefer the sound of the MF and the TF after the preamp.

I'm assuming that the hum has something to do with the interaction of the impedance of the loop and the buffers.  The Rebel loop has the following impedance :Send Impedance: 100 ohms;  Return Impedance: 220k ohms.   

I've tried changing the line levels and the bypass, but I haven't arrived at the right combo of bypasses and levels.

My rig starts with an LS buffer,  several overdrives (TS-808, Joyo classic OD, Analogman KoT)  a MXR vintage distortion plus,  and an Analogman bi-comp, each on independent true-bypass loops, which signal is sent into the front of the amp, then feeding my ModFactor and TimeFactor from the effect loop send, back through the return.  Everything is powered by a Voodoo Lab Pedal Power 4×4. 

Has anyone experienced a similar noise problem and can anyone offer any advice?

I love the amp, the ModFactor and TimeFactor, just not together.

Any help would be great.

Thanks

[nickrose]

It sounds like you have a large and complex setup, with a high likelihood of hum-producing ground loops. Diagnosing this is beyond the remit of this Forum – you may want to consider  professional advice.

That said, using a central power supply makes ground loops more likely. To see if this is the issue, try using the Eventide power supplies, which have no ground connection, and see if this makes a difference.

[johnfkiii]

Thanks; You're right I do need lots of professional advice,  on a number of issues.  (When did you talk to my wife, BTW?)   

All joking aside, I realize that the question has a technical aspect, but I was wondering if anyone has had a similar problem with a buffered effects loop, and what was their solution.  I'm more interested in any advice specifically with setup, as opposed to any technical forensics of the impedance issues-which would be over my head.

Thanks for the suggestion;  there's still noise with the Eventide DC wart.  There's no ground hum when the pedals are put in front of the amp with the rest of my signal chain, while still powered with the Vodoo Lab pedal power 4×4.  (The Pedal Powere 4×4  provides ground isolated DC power for all my pedals.  (Whisper quiet.)) 

I imagine that the hum is the interaction of the internal buffers in the pedal and the buffer in the effects loop.  I was hopping someone had some advice on (1) set-up of the input and output levels, the bypass and the killdry functions, on both pedals,  or (2) if anyone had any success with a specific effects loop buffer or an outboard send-return attenuator like the Ceriatone Klein-ulator.

Thanks

[Author]

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