3 channel Triple Rectifier Loop Mod.(Parallel to Series)

[krylon]

my TR never had this wire directly from the send to mix pot. the dry end of the mix pot had a wire going to the pcb like in the pic on the first page. i desoldered it and still had bleed. so i reversed it. i'm not about to jump thru all those rings on that mod in the OP. paralell loop it is for now.

 

[dlabrecque]

Why would you need to go to all this trouble? The *only* cause of the issue with phase and latency is the link from the Send level pot to the Mix pot allowing a small amount of dry signal through, so if you simply break this connection it's fixed. That leaves all the other functions of the loop working as normal.

(I don't have a Triple Rec by the way, I got directed to this thread from elsewhere, but I've done this mod to several Mesas and I can guarantee that it works perfectly.)

Just wanted to let everyone know that this worked for me. I recently bought a Boss Re-20 space echo and a volume pedal and wanted to run them along with a chorus pedal in my FX loop. I have a mid 90's 2-channel Dual Rectifier solo head and was quite frustrated by the residual (~10%) dry signal remaining in the chain when the mix knob was at 100% wet.

So, I found this forum, found this post, opened up my head, de-soldered the green wire running from the send pot to the mix pot, and wrapped the end with some electrical tape. It was extremely simple, took maybe 10 minutes. Fired my amp back up, the loop rotary dial still works (bypass, on red & orange, red only, orange only, foot switchable), and now no dry signal is passing through my FX loop when the mix is at 100% wet. Works just like I wanted it to. I couldn't be happier. Thank You 94Tremoverb :mrgreen:

Really appreciate the info, Mitch. So, are you saying that there has been absolutely no change in the way everything works, except for the 10% residual dry going away when the mix pot is set to 100%? Solo and master pots still work? All footswitches still work?

Or is it that the mix pot doesn't do any mixing anymore? Is it 100% wet all the time now, regardless of where the mix pot is set?

 

[Mitch Connor]

my TR never had this wire directly from the send to mix pot. the dry end of the mix pot had a wire going to the pcb like in the pic on the first page. i desoldered it and still had bleed. so i reversed it. i'm not about to jump thru all those rings on that mod in the OP. paralell loop it is for now.

Yeah, my 2-channel dual rectifier didn't have this sort of setup.

Really appreciate the info, Mitch. So, are you saying that there has been absolutely no change in the way everything works, except for the 10% residual dry going away when the mix pot is set to 100%? Solo and master pots still work? All footswitches still work?

Or is it that the mix pot doesn't do any mixing anymore? Is it 100% wet all the time now, regardless of where the mix pot is set?

Well, my Dual Rec. doesn't have a solo switch or any of that. It just has a single button footswitch to change between the orange and red channels. There is the single "Loop Active Master" that controls both channels' overall volume when the Loop is engaged, and yes that still works normally. The FX mix pot/knob doesn't blend the dry and wet signal anymore. I think someone (probably 94Tremoverb) mentioned that it now acts more like an FX return level. If I set it to 0% there is still a wet signal coming through, but the original parallel dry signal is completely gone. I like it this way, at 100% it appears to work just like a serial FX loop.

If I get a chance I'll pull the amp apart and attach a photo to show you what I did. Again, it was extremely simple and easily reversible. However, your situation may not be exactly like mine.

EDIT: Here are the photos. And if anyone was wondering why it looks like I'm missing tubes, I run my amp with the two middle power tubes removed. Also, the FX rotary knob is attached incorrectly which is why it's pointing to 'nothing'. It's actually set to "LOOP ON ORG & RED".

 

[dlabrecque]

Thanks, Mitch. Maybe I'll give it a whirl one of these days...

I have the three-channel dual rec, so I'm not sure how it looks inside.

 

[krylon]

in my 3ch TR (Rev. E i think). this is what it looks like, the wire circled in yellow is the wire that goes to the dry end of the mix knob. this is the one i desoldered then reversed.

 

[BIGKAHUNA]

in my 3ch TR (Rev. E i think). this is what it looks like, the wire circled in yellow is the wire that goes to the dry end of the mix knob. this is the one i desoldered then reversed.

Can anyone expand on the "reversed" part of the statement "desoldered then reversed"?

To perform this mod to a 3ch TR can the wire indicated in the pic simply be cut and insulated? Will this break the connection from the Send and Mix Pots that that is required for this mod?

Any help is greatly appreciated. Thanks.

 

[bortx]

i guess he means that he soldered it back when he says he "reversed" it

i have the same problem... which wire desolder?

 

[krylon]

yea i soldered it back, seems 94tremoverbs fix is really only for the 2ch breed of rec's. i'd just love some more input on the 3ch mod. there's a guy around here in new orleans that will do a series mod and amp inspection for 75$. wonder what he'd be doing exactly, guess i'll have to inquire some more

 

[bortx]

hi, I took my 3 channel dual to a technician after failing to mod it myself (it would still have some unprocessed signal going through the loop), he did it (tone was better after his mod) and still I had some residual signal passing through it. I told him, he did some tests and told me that the residual signal was due to some "grounding return" (whatever that means, providing i translated it correctly hehe) and the whole grounding scheme had to be rearranged...

Basically the residual signal I was hearing was very low (and wouldn't get lower when I crank the amp's volume) but still sucked tone if I tried to delay the 100% of the signal a few miliseconds as I am trying to do.

If I put a 1 sec. delay in the loop 100% wet, I will hear the guitar as I play it very quiet and a second later I will hear the delayed signal much louder. I'm using the TC Gforce and I'm sure the returned signal is 100% wet

anyone's got any information about this? any idea? I wrote mesa boogie but had no reply yet

 

[bortx]

The official answer from the Mesa Boogie Tech Support. The technician seems to have missunderstood the problem

Hello there,
thanks for your email.
I am not exactly sure what your tech is referring to. The reason you
still have a bit of signal passing through, is that- even if you have
modded your amp from a PARALLEL to a SERIES loop, the SEND & RETURN are
shared in the same 12AX7 pre amp tube... What you are experiencing is
"bleed" from each side of the shared tube. To my knowledge, there is no
fix for this.

 

[dlabrecque]

Just a reminder for those of you who may be frustrated with the tone-sucking bleed problem and are looking for an alternative...

My Dual Rectifier is factory stock (no mods). I've had good luck (though it takes some thinking and programming) being careful to set up patches on my effects processor (Boss GT-10) -- using the 4 cable method -- such that no common signal is ever sent to both the unit's SEND and OUTPUT. That way, you don't get any cancellation between a straight signal (processor SEND) and a latent signal (processor RETURN-to-OUTPUT) when they're mixed, however little, at the Mesa RETURN.

You can achieve this either by ensuring that any signal that comes from the Mesa's SEND to the processor's RETURN is not passed through the processor without some kind of delay or reverb set to 100% wet. (in this case you'll want to set the return mix knob on the Mesa to allow a decent amount of preamp signal to come through -- I think I have it at around 50%) The other option is to simply mute or mix out the processor's RETURN signal.

It's actually a very powerful way go, but it does take some thinking and planning to make all your patches sound good (suck-free).

 

[mastora]

Just a reminder for those of you who may be frustrated with the tone-sucking bleed problem and are looking for an alternative...

My Dual Rectifier is factory stock (no mods). I've had good luck (though it takes some thinking and programming) being careful to set up patches on my effects processor (Boss GT-10) -- using the 4 cable method -- such that no common signal is ever sent to both the unit's SEND and OUTPUT. That way, you don't get any cancellation between a straight signal (processor SEND) and a latent signal (processor RETURN-to-OUTPUT) when they're mixed, however little, at the Mesa RETURN.

You can achieve this either by ensuring that any signal that comes from the Mesa's SEND to the processor's RETURN is not passed through the processor without some kind of delay or reverb set to 100% wet. (in this case you'll want to set the return mix knob on the Mesa to allow a decent amount of preamp signal to come through -- I think I have it at around 50%) The other option is to simply mute or mix out the processor's RETURN signal.

It's actually a very powerful way go, but it does take some thinking and planning to make all your patches sound good (suck-free).

Are you using 4cm? I also have a gt 10 and use it mostly in manuel mode. How do set the gt to do what you say?

 

[dlabrecque]

Just a reminder for those of you who may be frustrated with the tone-sucking bleed problem and are looking for an alternative...

My Dual Rectifier is factory stock (no mods). I've had good luck (though it takes some thinking and programming) being careful to set up patches on my effects processor (Boss GT-10) -- using the 4 cable method -- such that no common signal is ever sent to both the unit's SEND and OUTPUT. That way, you don't get any cancellation between a straight signal (processor SEND) and a latent signal (processor RETURN-to-OUTPUT) when they're mixed, however little, at the Mesa RETURN.

You can achieve this either by ensuring that any signal that comes from the Mesa's SEND to the processor's RETURN is not passed through the processor without some kind of delay or reverb set to 100% wet. (in this case you'll want to set the return mix knob on the Mesa to allow a decent amount of preamp signal to come through -- I think I have it at around 50%) The other option is to simply mute or mix out the processor's RETURN signal.

It's actually a very powerful way go, but it does take some thinking and planning to make all your patches sound good (suck-free).

Are you using 4cm? I also have a gt 10 and use it mostly in manuel mode. How do set the gt to do what you say?

Yes, I'm using the 4-cable-method. You have to read the Boss user manual to get a grip on how to program the GT-10, but basically it comes down to being sure -- for any patch that you create -- that no effects in the internal effects chain POST the GT-10's send/return pass any dry signal, but only delayed signal (like delays and reverbs set to 100% wet). This way the latency caused by the GT-10's RETURN A/D conversion and signal processing thereafter will not create problems when the GT-10's OUTPUT is mixed back in with the Mesa's preamp signal at the Mesa's RETURN. The cool thing about the GT-10, and perhaps other processors, is that you can change the order of effects in the internal effects chain for maximum flexibility.

Here's the overview:

Use the 4 cable method (guitar to Boss INPUT/Boss SEND to Mesa INPUT/Mesa SEND to Boss RETURN/Boss OUTPUT to Mesa RETURN).

Set the Mesa's return mix knob to 50% (you can play with it from there if you like).

Any effects that you want to put on the post-preamp signal (i.e., after the GT-10's send/return point) must be set to 100% wet in order to avoid the tone-suck caused by the latent dry signal mixing back in with the non-latent post-preamp signal.

Example:

"I want a nice reverb on my killer Dual Rectifier distortion."

Set all as above (see overview). Be sure a reverb effect is placed after the send/return point in the Boss effects chain. Be sure the reverb is set to 100% wet. Adjust the reverb's output level to adjust the wetness factor of the sound coming from your cabinet. If you can't get enough wetness, see if there's another post-reverb level you can turn up (either in software, or maybe the hardware output control on the Boss), or turn up the Mesa SEND knob, or turn up the Mesa mix knob. I'll leave it to you to decide which approach will optimize the gain staging for your rig.

 

[mastora]

I'll give it a try and let you know how it goes. I won't be able to do it until some time next week though. I aprreciate your time explaining this to me. Thanks!!

 

[dlabrecque]

I'll give it a try and let you know how it goes. I won't be able to do it until some time next week though. I aprreciate your time explaining this to me. Thanks!!

Happy to help. I hope that's what I'm doing. Do keep us posted. I still have a little trouble getting my head around it when programming the GT-10, but since you forced me to boil it down to something more-or-less bite-sized, hopefully, it'll be simpler in the future. :lol:

 

[mastora]

Well after tinkering with the mesa loop and gt 10 i found that i can get some good results with the clean channel, but channels 2 and 3 are a completely different story. I'm going to go over the gt10 manuel an see if I can find something like you say...like setting the WET to 100% etc. I have to admit, I'm getting frustrated and am just about ready to try the serial loop mod. :evil:

 

[dlabrecque]

Well after tinkering with the mesa loop and gt 10 i found that i can get some good results with the clean channel, but channels 2 and 3 are a completely different story. I'm going to go over the gt10 manuel an see if I can find something like you say...like setting the WET to 100% etc. I have to admit, I'm getting frustrated and am just about ready to try the serial loop mod. :evil:

Sorry to hear of your troubles. As long as your reverb is set to anything but 0 for the direct signal, you're likely to get tone suck (the reverb must also be AFTER the send/return in the FX chain). I just set up a couple new patches, and it worked fine. Why don't you try setting up a simple reverb-only patch to learn how to do it correctly, and bolster your confidence?

I did it the other night by putting the Send/Return "module" just prior to the preamp "fork" in the FX chain, then putting the reverb downstream from there, just before "DGT" and the speaker cab icon at the end of the chain. I dialed the reverb up to about 40% wet, 0% dry. I have the Send/Return set to "normal" mode and both send and return levels to 100. All other FX are OFF. This means all the little buttons under the "EFFECTS SELECT" section above the 1, 2, and 3 pedals are NOT LIT -- except the REVERB button, which is lit, because it's turned on for this patch. To turn off a lit button, press it once to select it, then again to turn it off (bypass it).

Also set up the 4cm and set the knobs on your Mesa as I instructed earlier.

Can you do that okay? Or do you need a walk-through?

 

[mastora]

Check your pm. I don't want to continue this subject on this thread because its supposed to be about modding a parallel loop. But thanks again for your help.

 

[facefirst]

So is there a way to mod the effects loop to Series where the amp still retains ALL functionality (including the footswitch)?

I'm running a Line 6 M13 and I'm getting an out of phase problem any time I engage the FX loop. Driving me nuts.

 

[agnesrocs]

I just did the DR loop mod to series.
I have a G major 2 and a voodoo lab ground control pro.
Before the mod I used the effects loop on off switch to turn effects on and off.
Now my loop is always on how do I turn the effects off?
Thanks