Big Volume Drop with Insert Loop? (PBC/6X)

M

Maracudi

Member
Hi Ron and co., I just wanna say first and foremost that I'm absolutely in love with this unit and its endless customization options. Beautifully designed! I'm so close to getting this stereo rig build I planned for months all set to go.

So basically, I have loops 4, 5 and 6 (H9x2 and a Ventris, respectively) in stereo, and output set to stereo as well. For physical configuration reasons with the underside of my board, I elected to have my EP Booster in the Insert loop since I can obviously move the loop order around per patch.

For both my gritty clean and dirty lead patches, I have that Insert loop placed before the stereo loops. When I turn it on, there's a huge volume drop. Even with the EP Booster cranked. I made a preset that's only the EP Booster and it's the same issue. I have the pedal's internal +3db switch activated, and I've tested it solo with my guitar and practice amp-- it works as expected. Furthermore, I just tested the patch cables I was using (Mogami + Squareplug) and they're totally functional.

What can I do from here? I've attached my settings file. Thank you so much in advance for your help!
 

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  • Maracudi PBC6X 11-29-2021.rjs
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The EP Booster has a high output impedance, which can be problematic. That might have something to do with it. For example, it might not like having its signal split and going into both the left and right inputs of the next pedal.

If you turn off the EP booster using its built in switch, then turn on the loop, is there a volume drop? Or, if you change the order so that there's a pedal in between the EP and the first stereo pedal, does that help?
 
I'll have to do some spaghetti navigation to wire the EP Booster back in (disconnected it to make sure it's functioning normal, as mentioned above) but for now I can absolutely tell you that there's a volume drop both with the pedal in the insert loop when disengaged and when the loop is on but there's no pedal plugged into it. Albeit, I dunno if the second scenario is an obvious expected result.
 
Also Ron, if it would be wiser for me to basically have my stereo pedals (2x H9s + Ventris) moved up 1 loop so they're in 5, 6 and the Insert, I can totally do that. Full disclosure, I was hoping to use a stereo loop (so in this hypothetical, 4) in split mono with the EP Booster and a forthcoming MXR Timmy.
 
Maracudi said:
I'll have to do some spaghetti navigation to wire the EP Booster back in (disconnected it to make sure it's functioning normal, as mentioned above) but for now I can absolutely tell you that there's a volume drop both with the pedal in the insert loop when disengaged and when the loop is on but there's no pedal plugged into it. Albeit, I dunno if the second scenario is an obvious expected result.
Click to expand...

Another thing to look out for is to make sure that your settings always match the cables you're using. For example, if any loop send, return or output is set to stereo but you plug a mono cable into it, you will have a problem. For example, you have to go into settings and change the output to mono if you're using a single amp in mono connected with a mono cable.

If there are no mono/stereo conflicts, there's nothing plugged into the insert loop (not even cables) and it still causes a level change when you turn on the insert loop, something is wrong with the PBC. (assuming that no other loops are turned on)
 
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Yep, loops 4-6 are set to stereo but the insert isn't. Just unplugged the EP Booster and its cables from the PBC, made a new completely dry preset and turned the insert loop on and off. Unfortunately, I can confirm the volume drop is very much present. How should I proceed from here?
 
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Maracudi said:
Yep, loops 4-6 are set to stereo but the insert isn't. Just unplugged the EP Booster and its cables from the PBC, made a new completely dry preset and turned the insert loop on and off. Unfortunately, I can confirm the volume drop is very much present. How should I proceed from here?
Click to expand...
Email us at support@rjmmusic.com and we'll figure out the rest
 
One more thing - you have the PBC's output set to stereo. Are you plugging a TRS cable into the output? Using a mono cable in a stereo configured jack would cause the problems you're describing.
 
Yep, I run my rig into an Iridium at home made a TRS cable the other night expressly for running the PBC into it (you're probably aware, but the Iridium has a single TRS input jack). Just to be certain, however, I swapped in a Coluber TRS cable I bought online some years ago (has Neutrik plugs, etc). The problem is persisting.

I don't think I changed anything super-crucial in the Editor since posting my config file yesterday, but just in case here's the most current version.
 

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  • Maracudi PBC6X 11-30-2021.rjs
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@rjmmusic Hi Ron, I'm having this same issue with EP booster in a split loop (4/7). I don't here a volume drop when I bypass the pedal or even when it is on by itself, but whenever a loop is engaged after it, the volume drops and the bottom end falls out and gets brittle. I'm assuming this is the output impedence problem? Any advice on how to fix this? Currently happening on two of my pedals (Xotic EP Booster and MXR Duke of Tone). Thanks!
 
mb-jenks said:
@rjmmusic Hi Ron, I'm having this same issue with EP booster in a split loop (4/7). I don't here a volume drop when I bypass the pedal or even when it is on by itself, but whenever a loop is engaged after it, the volume drops and the bottom end falls out and gets brittle. I'm assuming this is the output impedence problem? Any advice on how to fix this? Currently happening on two of my pedals (Xotic EP Booster and MXR Duke of Tone). Thanks!
Click to expand...
I don't know about the Duke of Tone, but the EP booster definitely has a high output impedance. The first thing to check is the cable on the pedal's output. If there's a partial short in that cable - or any cable in any active loop after that loop, it would show up as volume and tone loss. I recommend trying other cables, and temporarily wiring it as a non-split loop just to see if the problem goes away.
 
@rjmmusic hey, yes, is appears the cables could be causing this. I tested with putting a buffer after the pedals immediately and it seemed to go away. Slightly off topic, I used mogami cable and the square plugs and soldered them myself (tested with multimeter on each one) but I guess I didn't detect any of the partial shorts (which appear to be a problem with lots of the cables now). What does a partial short consist of and how can you test for that? Is it due to the conduit around the "tip" touching the pins in the plugs? Looking like I have a lot of rewiring work ahead of me.
Love your product and thanks for thelp.
 
mb-jenks said:
@rjmmusic hey, yes, is appears the cables could be causing this. I tested with putting a buffer after the pedals immediately and it seemed to go away. Slightly off topic, I used mogami cable and the square plugs and soldered them myself (tested with multimeter on each one) but I guess I didn't detect any of the partial shorts (which appear to be a problem with lots of the cables now). What does a partial short consist of and how can you test for that? Is it due to the conduit around the "tip" touching the pins in the plugs? Looking like I have a lot of rewiring work ahead of me.
Love your product and thanks for thelp.
Click to expand...
Mogami cable is famous for this problem. The black material around the center insulator is conductive. You can't let it touch anything that's carrying a signal. Here's something I wrote up about this problem, and how to fix it:

A Note About Making Cables

We get a lot of tech support calls from our customers asking why their signal sounds dull and muted when turning on certain loops on their RG-16 or Effect Gizmo. So far, every time it's been traced to cables that have not been made properly. Most guitar cable (or most good guitar cable) is made...
www.rjmmusic.com www.rjmmusic.com
 
Thanks so much for the advice and direction! Going to take a good bit of work to fix all the cables but will report back
 
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