Line 6 M13 out of phase, comb filtering. Resolved

[biddifour]

Long story short. Had a 2002 recto. Learned right away that digital effects and parallel loops don't work. Used a reverb pedal, done.

Been through hell ever since selling that amp, but I find myself with a new multi-watt recto and no effects till today.
I decided that I wanted the Line 6 M13 for all it can do and assumed that since the recto's loop is now parallel, that I should have no problem. So I spent a good amount of cash to buy one. Plugged it in and it's like I'm back to early 2000's with my Boss GT-6. Out of phase nasely, comb filtery ****. Absolutely unusable. Called Mesa and he said "with that much gain, (2:30-3:00), there is tube bleed", etc, etc.

Why? What is the fix? He said I could try swapping v2 and v3, but I have no other problem, so I think the tubes are fine. Haven't tried that yet, but I may

I'm just so frustrated. I've researched and read everything I could find about this problem, and all I could find was stories relating to the old parallel loop, but no one explaining this problem with a series loop from any manufacturer.

Used to play with a buddy with a Marshall TSL and a GT-10 and everything sounded friggin great. So I was sure this setup would work.

Yes, I've connected it right. 4 cable method, just in the loop. doesn't matter. If I tried just reverb and put the wet/dry to %100 wet, all I get is that. No original signal. So there's no work around there. There is no global setting in this unit that I can find that would route any different.

I just think that it doesn't work.

I am considering a G Major 2, but don't want to wind up with the same problem and I don't want to spend $400 on 3 pedals for chorus, delay, and reverb. But I have a feeling that's what I'll have to do.

Anyone have this unit AND a multi-watt recto and get it to work? Please show me a vid so I can see/hear it work and then tell me how.

Another question is, if I go to channel 3, (with loop on), and turn the output ALL the way down, I can hear the distorted signal. It's just a little louder than the guitar acoustically. Is that normal? It's less on channel 2 and nothing on the clean channel.

Thanks in advance for anyone's help

 

[Gontur]

Plug your guitar in input.
Plug a jack in FX send - dont plug anything in FX return.
Play.
If the loop is serial there should be no sound coming from your speakers.
If signal is coming through speakers your Fx loop is bleeding.

 

[biddifour]

Plug your guitar in input.
Plug a jack in FX send - dont plug anything in FX return.
Play.
If the loop is serial there should be no sound coming from your speakers.
If signal is coming through speakers your Fx loop is bleeding.

Thanks! Did that already, and there is! Mesa says that's normal. I can't see how. They suggested I swap v2 or v3. Tried that earlier today with no change.

Is there a fix to the bleed? Is it normal for the new multi-watt? Could someone else just test this for me please?

 

[elvis]

It won't help to get a different FX unit.

First: 12AX7 tubes are not a single amplifier. They are DUAL amplifiers. So each 12AX7 has two separate amplifiers in it, that may be used anywhere in the amp. Usually they are used in series, so V1A and V1B (the two amplifier stages in tube V1) will tend to be used as input amp and second gain stage.

When there is a tube reverb or tube FX, one tube will tend to be used so that one half is the FX loop driver and the other is the FX return buffer.

Physically, inside a tube there are high-velocity electrons flying through a vacuum. Most get picked up by the appropriate channel, but a few slip over to the OTHER channel.. This is tube bleed (or crosstalk, or feedthrough). Some individual tubes are physically less prone to this, so swapping can help, but there is no real fix.

This tube bleed generally is only noticeable when the amp master is turned way down, as the feedthrough is a LOT smaller than the main signal. However, if you turn it down to be quiet at home, the bleed becomes way more noticeable.

So if you are playing with the volume down, turn it up and see if that doesn't fix it.

Also, some Mesa amps are set up so that the reverb bypasses the FX loop. If this happens, then the amp's reverb is ALL bleed in effect, and will always cause this problem. If you want to use digital effects in the FX loop of these amps, you will need to switch the reverb off completely. Generally not an issue, as the digital FX box will probably have reverb. Check your amp manual.

 

[3124+]

The circa 2002 Recto parallel loop is pretty much the best fx loop design there is. Most users don't know how to set it properly though. The trick is to think of it like an aux send on a mixing console.

 

[domct203]

The circa 2002 Recto parallel loop is pretty much the best fx loop design there is. Most users don't know how to set it properly though. The trick is to think of it like an aux send on a mixing console.

If you have ever tried to use an EQ or noise gate in that loop you would change your mind.

As mentioned, cross-talk or bleed inside a 12AX7 is unavoidable, but at gig levels it should not be noticeable at all. If you still have these issues at gig volume you might be overdriving the input of the loop, making the bleed worse. Where do you have your send level on your amp, and how hot is the output of your effects unit?

You could also swap out your FX driver tube (V4) to see if it improves.

I use a G-Major in the serial loop of my Roadster and have no issues at band volume.

Dom

 

[biddifour]

Thanks guys. I have come to terms with the situation finally. lol

I am frustrated by the fact that to enjoy using digital effects, I must use gig/band volume. I mean, it makes sense. The amp is designed for the biggest of venues.

But I am struggling with MS in my later years and just want to play at home and have it sound awesome at any volume.
I know there are endless options to do this, but I wanted the recto sound. I've tried no less than 6 high end amps since I sold my first recto and none come close to that sound. You guys get it, I'm sure.

So now I'm considering just using chorus, delay, reverb pedals from TC Electronic. When I first got this new amp I did try a cool pedal from Earthquaker Devices called Dispatch Master. It was a delay/reverb pedal. It worked fine in the loop, so I imagine these TC pedals should as well. But this pedal did color the tone ever so slightly. That's why I got rid of it.

I also wonder about a hotplate or something that would let me turn it up without the volume. Would it overtake the bleed?

Uggh. decisions!

 

[Gontur]

You wrote "If I tried just reverb and put the wet/dry to %100 wet...etc". Are you talking about the mix knob on the rear of your amp? If the answer is "Yes" your recto is not the new multi-watt reborn. It's the old Rectifier with parallel fx loop.

 

[biddifour]

You wrote "If I tried just reverb and put the wet/dry to %100 wet...etc". Are you talking about the mix knob on the rear of your amp? If the answer is "Yes" your recto is not the new multi-watt reborn. It's the old Rectifier with parallel fx loop.

No, I meant on the individual effects on the M13.

 

[biddifour]

Well, I decided to go the TC Electronic pedal route.

Should work fine. Thanks for the help

 

[afu]

What I've been finding on mine is this:

• The Channel Volume is the last thing before the loop.
  When the loop is engaged, many people -including myself- might turn up the channel volume.
  Turning up the Channel Volume will push V4a (Loop Send) more, until it eventually overdrives.
  The higher the signal into V4a, the worse the bleeding and overdrive.

My amp is an old 3 Ch with a serial mod. When I explain the fix for this, it might be different for others with stock amps or different models.

How I fixed mine:

• Setup the channels with the loop bypassed.
  Engage Loop.
  Turn up the Output to at least 10:00 and up to 1:00.
  Increase the FX Send until the volume is as loud as the bypassed level (or where it works for you, while being pretty loud).
  Try not to increase the Channel Volume very much at all.

I leave my loop on all the time and kill/change effects at the unit. If a person wants to use the loop switch, the Channel Volume and Send will need to be balanced against each other. For purposes of reducing the crossover and keeping the loop clean, the FX Send should be the one that is forced to be run at a higher setting in relation to the Channel Volume.

On mine, Modern is run at 9:15 or lower; Vintage is run at 10:00 or lower; Raw is run at 10:30 or lower. This approach improved the overall tone by a very large degree and I would recommend it to anyone. If you, or anyone else with a fully functioning loop, tries it, please let me know the details of getting it set up to balance loop on/loop off, so I can share it on my blog.

 

[elvis]

Well, I decided to go the TC Electronic pedal route.

Should work fine. Thanks for the help

I hate to say it, but the problem is that amp, so this will probably not help. You might be better off with a Mini Rectifier to run a bit quieter. Alternatively, use a power attenuator so you can run the amp with big signals but kill the volume at the end.

At home I use a Rock Crusher with one of my amps which works quite well. For another amp I use a Palmer PDI-03 into small powered monitors. That also works very well, and I can run all of them via a small mixer to add my iPod for jamming along. I can use headphones from the board or use the small monitors quietly or a bit less quietly and it sounds quite good as well. I've done the same thing with a CabClone, too.

Sorry about your health problems.

 

[biddifour]

Thanks Elvis.

Well as a final update on the matter, I bought the TC Electronic HOF reverb mini, Flashback delay mini, and Corona chorus mini.

All 3, great pedals, and work fine in the loop. They all have Analog-Dry-Through, so there's no a/d d/a conversion thus, no out of phase sound. Sounds great.

Maybe someone can come up with a mod to make the series loop truly serial. Then we could use some digital effects.

 

[3124+]

If you want truly serial, the Soldano SLO loop is the best you can get. It uses one whole 12AX7 as the send buffer, then an entirely separate 12AX7 for the return. Zero cross-talk with this design.

 

[elvis]

Thanks Elvis.

Well as a final update on the matter, I bought the TC Electronic HOF reverb mini, Flashback delay mini, and Corona chorus mini.

All 3, great pedals, and work fine in the loop. They all have Analog-Dry-Through, so there's no a/d d/a conversion thus, no out of phase sound. Sounds great.

Maybe someone can come up with a mod to make the series loop truly serial. Then we could use some digital effects.

Ah, didn't know that. Thanks for the info!

 

[afu]

Thanks Elvis.

Well as a final update on the matter, I bought the TC Electronic HOF reverb mini, Flashback delay mini, and Corona chorus mini.

All 3, great pedals, and work fine in the loop. They all have Analog-Dry-Through, so there's no a/d d/a conversion thus, no out of phase sound. Sounds great.

Maybe someone can come up with a mod to make the series loop truly serial. Then we could use some digital effects.

That isn't really an option on a manufactured design, short of installing another 12ax7.

The fix I use above limits the amount of signal coming into the loop. Most 12ax7 stages are always working at full power. The trick with crosstalk in the loop is to make the input signal small enough that it comes out big enough to use, but not so large to be pushing the stage hard. The FX Send doesn't make the loop amplify any more or any less; it only dumps some of the signal that's already amplified by the Send stage. So, the Channel Volume would control the size of the signal into the loop and is the culprit when crosstalk is an issue.

 

[elvis]

Maybe someone can come up with a mod to make the series loop truly serial. Then we could use some digital effects.

Easier to use a power attenuator, and about the same price as modding the amp.

 

[domct203]

I have no issues with my (digital) G-Major in the series loop of my Roadster.

Dom

 

[biddifour]

Maybe someone can come up with a mod to make the series loop truly serial. Then we could use some digital effects.

Easier to use a power attenuator, and about the same price as modding the amp.

True, but I wonder about tone with those things. Never tried one though.

 

[biddifour]

I have no issues with my (digital) G-Major in the series loop of my Roadster.

Dom

That's awesome. But I have read that the Roadster loop is different/better/more serial loopish. Dunno, Just what I've read, and I DID NOT sleep at Holiday Inn Express last night..soooo...