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

[Freaker]

Hello guys, I'm a new 3 channels Triple Rectifier owner. I need to use my Boss GX700 into the effects loop to get all the different sounds I use. The problem is already known by all of you. Lost of volume, change of tone and a very dissapointing use of effects.
I want to make the series loop mod, but I havent found something directly related to the 3 channel Triple Rect. I would like someone to send me some schematics, and better, some intructions about how to do it. Also I would like to keep the posibility of bypassing the loop, at leats manually. I know about people who have a switch for series or parallel mode. If someone has this mod, please tell me if the change of tone issue(having the loop on and the effect unit on it) is solved or it is still there.

Thanks a lot.

 

[boxcarmonument]

Here's a 3ch Dual Recto before the Mod.

Here's The same Amp after the mod.

Follow the directions and you can't go wrong. Although this is a Dual Recto I believe the same applies to the Triple Recto.
It's the Single that's different from the 3 rectos.

Good luck,
Dave
.

 

[Freaker]

Thanks for the pictures.
And about the change of tone and the possibility of keeping the switch on/off of the loop???? Can you tell me something about this??
Talking about the pictures, what do I do with the three grey wires???

Thank you very much.

 

[boxcarmonument]

The 3 grey wires go to the pot for the line out level. So you can disconnect them from the pot or remove the pot.
Your choice. As far as fixing the sound with effects in the loop it will fix them. Especially if they are digital effects.








Good luck!

Dave

 

[Freaker]

Ok, thanks Mark I. A last question. Is it necessary to remove the three proged things that you say?? What is their function?? I have removed the whole plate where the rear jacks are and I think it can be safer for the amp (due to use the iron solder int the plate),to remove the wires from the pot, and solder the second and third wires together and isolate the first one. And about those three things, I just want to know if it is completly necessary to remove them and do the connection with the jumper wires.


Thanks again

PD: Another question to people who are really into electronics... do you imagine a way to make this mod through a switch?? I mean, change from parallel to series using a switch. I know that a technician here in spain does it, but it's too expensive for me to send the amp and pay the mod cost.

 

[mikey383]

Those 3 three-pronged thingies are transistors. I suspect they are there to recover any gain lost from the loop.

The mod is actually a little easier than that, and you don't have to remove the transistors:

The 0 ohm resistors are those blue ones beside the jacks with the single black stripe.

[EDIT]I removed the footswitch mod because I don't have the complete documentation.

 

[mcnamee]

Did anyone try the above instructions from mikey383? His handwriting a little tough to make out.

I have the same issue, I would prefer to try this myself rather that ship it off to voodoo amps for the modification. But I'm a little hesitant about haphazardly chopping up a $1400 amp

Any words of experience out there?

thx

 

[mikey383]

That's not my handwriting BTW, that's straight from Mesa. But here it is typed out for you:

1) Lift wiper wire of send and mix pots from rear jack board
2) Lift forward end of 0 ohm resistors next to send and return jacks
3) Add jumper from mix pot's empty pad to lifted end of return jack's 0 ohm resistor
4) Extend send pot's wiper wire to lifted end of send's 0 ohm resistor

 

[mcnamee]

Excellent, thanks for taking the time to type it out. It's cool that Meas will actually send you that kind of stuff, great PR.

 

[dlabrecque]

Just getting up to speed on this mod.

I understand that the FX loop switching at the footswitch is disabled by the mod, but that a mod to the footswitch fixes that. Do I understand right?

Also -- I thought I'd read that the mod also kills the solo and/or master output functionality. Is this true? If so, is there are fix for that/those losses?

Many thanks.

 

[Jerrick]

Would the Parallel to Series mod fix my issues?

Flip the loop on for red and orange channels, and it sounds horrible. Volume is very compressed and pinpointed, instead of being full and massive sounding. It was also really fizzy and scratchy.

So I bypass the loop and all is well.

I have a 2-channel dual rectifier, so are there any drawbacks for me here? All I hear about is the footswitch options on 3-channel rectifiers.

 

[muramasa]

Would the Parallel to Series mod fix my issues?

Flip the loop on for red and orange channels, and it sounds horrible. Volume is very compressed and pinpointed, instead of being full and massive sounding. It was also really fizzy and scratchy.

So I bypass the loop and all is well.

I have a 2-channel dual rectifier, so are there any drawbacks for me here? All I hear about is the footswitch options on 3-channel rectifiers.

I have a 2 ch triple rectifier and I used this http://forum.grailtone.com/viewtopic.php?f=4&t=28828 to convert mine to a serial loop. Problem was that even with this mod I still got bleed through. It wasn't any differnent than turning the mix and level knobs to 100%

 

[flimz]

That's not my handwriting BTW, that's straight from Mesa. But here it is typed out for you:

1) Lift wiper wire of send and mix pots from rear jack board
2) Lift forward end of 0 ohm resistors next to send and return jacks
3) Add jumper from mix pot's empty pad to lifted end of return jack's 0 ohm resistor
4) Extend send pot's wiper wire to lifted end of send's 0 ohm resistor
That's not my handwriting BTW, that's straight from Mesa. But here it is typed out for you:

1) Lift wiper wire of send and mix pots from rear jack board
2) Lift forward end of 0 ohm resistors next to send and return jacks
3) Add jumper from mix pot's empty pad to lifted end of return jack's 0 ohm resistor
4) Extend send pot's wiper wire to lifted end of send's 0 ohm resistor

If this mod is directly from Mesa, will having an authorized Mesa tech do this mod void my warranty? Im guessing it will.

 

[msi]

Two of the three transistors are to enable and bypass the send and return jacks. Those are marked J125s, and J125r. The one marked J125m is part of the mute circuit and is there to lessen pops during channel switching. Without it you're liable to have the pop repeat during delay echos. I don't see any reason to remove j125m as it is not part of the loop circuit rather it's part of the channel switching circuit. Likewise the solo function should not be affected by this mod. Because J125s and J125m are bypassed and those control the loop on and off function, you can not disable the loop, and no number of modifications to the foot switch will change that.

 

[dlabrecque]

I have a 2 ch triple rectifier and I used this http://forum.grailtone.com/viewtopic.php?f=4&t=28828 to convert mine to a serial loop. Problem was that even with this mod I still got bleed through. It wasn't any differnent than turning the mix and level knobs to 100%

Are you saying that particular mod made no difference at all?

 

[dlabrecque]

If this mod is directly from Mesa, will having an authorized Mesa tech do this mod void my warranty? Im guessing it will.

The tech I spoke to the other day gave me the impression that this was not an "official" Mesa mod, though he did email me the PDF.

But that's a good question.

 

[livewire78602]

You figure as much as you spend on these heads, Mesa should recall all triple rectofiers to fix the volume loss when using the effects loop, especially when on the green clean channel, so noticable.

 

[dlabrecque]

It mentions it in the manual, so I'm guessing it was an accepted aspect of the design. I wonder if it's simply a 3 dB drop due to the double termination that enabling the loop creates. It feels like about that much signal drop to me.

Perhaps the way to look at it is that the way to achieve no signal drop would be to have the loop on-line (but muted) full-time, which would cause some degradation in fidelity (S/N?). Mesa gave us the purest possible chain at all times, at the cost of a change in level when the loop is patched in.

Or maybe I'm full of $h*t? :lol:

 

[newm1ke]

Heya guys, for those that have tried this mod - does this proper stop any dry sound coming out, so its definitely all effected sound? And what knobs are disabled with this mod, is the Output one still working?
Also what jumper-wires are you using in that picture? Thanks very much

 

[sflight]

I recommend selling your effects and get ones that will work with the parallel effects loop. (Analog)..