More Triple Rectifier FX Loop Problems

[mrb1946]

When I have pedals in my FX Loop on my 3 ch Triple Rectifier and turn one of them on, the volume drops a significant amount. Here is a demo of me showing this problem. What can I do? I have the return gain set to 100% and the Send gain set to 50%.
http://www.youtube.com/watch?v=2n2Xg2zJAZM

 

[UnderJollyRoger]

I don't know about the older Rectifiers, but when you put Send to 50% I would guess you are giving only half the signal to the fx loop and take that back into the Return later ... ? Therefore the volume loss ...

Try setting the send to 100% and see what happens.

 

[94Tremoverb]

No, that will make it worse. What's happening is that the pedals have too low headroom to handle the level in the loop, so they distort and limit the signal to a quieter volume. The Phase 90 in particular has very low headroom - it will even clip on a hot guitar signal if it's in front of the amp. What to do is to *lower* the Send level (50% is quite hot, actually) and raise the Output Level to give the same final volume. I run the Send level on my Tremoverb at about 10 o'clock with an old MXR in the loop, which is as hot as it will go before the pedal clips - I'm not sure if the loop is exactly the same level on the 3-channel, but it must be close.

There is also an issue with the Phase 90 in that it reverses the phase of the dry signal (ie inverts its polarity, not because it's a phaser!), but the effect of that isn't so drastic and shows up more as a thinning of the tone than a volume drop. The only way to cure this one is to change the loop to series.

 

[volatileNoise]

Just watched your vid and it seems odd, I have a 3ch DR which is identical FX loop wise, and never had that much signal drop.

One stupid (no offence) question, the output on the black pedal is definitely going to the return?

I have only ever encountered a similar thing I think by having a pedal back to front I think, or plugged into input B on a delay pedal instead of the main input... Can't really remember.

I run two boss delays, and a malekko reverb, and with all three pedals I have no real drop in level at all, and at the moment run the send around 50% or a fraction under, and the mix level at just under 100% to achieve this.

I am not familiar with using MXR stuff though, maybe they are more suited for use out front rather than the loop, but like I said I can't say as I have no experience with them.

When I was first setting up the loop, I used to run the send at 40% and mix at 100% maybe see if that helps, and also lift the mix level on the pedals, I have found that can sometimes have an effect with certain pedals.

Good luck though, and keep us posted on your findings.

*and also I use a 1spot too, and have powered 4 pedals with it and a floor tuner - no problems at all.

 

[domct203]

Trem is right on. To much signal is going to clip the input stage of those pedals. Try lowering the send.

Also, what are your channel masters set at? They feed the FX Loop before the send level. Try to keep them around 10:00-11:00.

Dom

 

[mastora]

Trem is right on. To much signal is going to clip the input stage of those pedals. Try lowering the send.

Also, what are your channel masters set at? They feed the FX Loop before the send level. Try to keep them around 10:00-11:00.

Dom

Does that mean that the Master volume has to be at 10-11 too, if you are using the solo boost?

 

[twothemax]

no master vol controls overall output of the 3 channels. i run my boss delay at max and my send level on my amp at about 10% no problems.
that is how a parallel fx loop works. think of an fx loop on a mixer. hope that helps.

 

[mrb1946]

Ok, I tried setting my send gain lower and higher. I also tried setting my return gain a little lower. Nothing worked.. I tried moving my Phase 90 to in front of the amp and I didn't notice a volume drop. So I guess it definitely has something to do with the loop?.. Would it be worth it just to try to Series FX mod?

 

[UnderJollyRoger]

What happens when you just put a cable between send and return ?

 

[mrb1946]

What happens when you just put a cable between send and return ?

I just tried and the tone and volume stayed basically the same. No loss in volume. No suckage of tone.

 

[volatileNoise]

What happens when you just put a cable between send and return ?

I just tried and the tone and volume stayed basically the same. No loss in volume. No suckage of tone.

This equates to exactly what I thought, either you have hooked up the pedals back to front in the loop, or these pedals simply don't take well to being used in an fx loop.

 

[94Tremoverb]

They can't be the wrong way round, or you would get no effect as well, which doesn't seem to be the problem. So I think it must come down to the phase issue, which is surprising as I've not found it makes that much difference to the volume. But having thought about it there may be another possibility - if the output impedance of the pedals is quite high, they may not work well with the input impedance of the Return jack on the amp, which is quite low (basically the 25Kohms of the Mix pot). I wouldn't have noticed this with my set-up, because the MXR in my loop is followed by several other pedals, all with low-impedance buffered outputs.

To fix this, you may need to run the pedals in a buffered loop pedal, like the Boss LS-2 Line Selector, or follow them with some other low-impedance, fully-buffered pedal (any Boss/Digitech etc will do, if you have one you can use to test it).

 

[mrb1946]

They can't be the wrong way round, or you would get no effect as well, which doesn't seem to be the problem. So I think it must come down to the phase issue, which is surprising as I've not found it makes that much difference to the volume. But having thought about it there may be another possibility - if the output impedance of the pedals is quite high, they may not work well with the input impedance of the Return jack on the amp, which is quite low (basically the 25Kohms of the Mix pot). I wouldn't have noticed this with my set-up, because the MXR in my loop is followed by several other pedals, all with low-impedance buffered outputs.

To fix this, you may need to run the pedals in a buffered loop pedal, like the Boss LS-2 Line Selector, or follow them with some other low-impedance, fully-buffered pedal (any Boss/Digitech etc will do, if you have one you can use to test it).

It's got to be this. I tried plugging in a wah pedal after my delay in the loop (not to use it, but just to try this buffer thing) and the volume stayed the SAME!! Thank you so much for helping! I'll be picking up a buffer pedal soon

 

[mrb1946]

Ok, could I use a Boss NS-2 as the buffer thing? I need to pick up a noise supressor and killing two birds with one stone is never a bad thing

 

[94Tremoverb]

Yes, that should work fine.

Thanks, I learnt something new about yet another aspect of the Mesa loop!

 

[mrb1946]

Yes, that should work fine.

Thanks, I learnt something new about yet another aspect of the Mesa loop!

we'll take all the learning we can get! lol... So do you know if I put that NS-2 at the end of my loop, it will color my tone at all? I've heard things about that, but I know most people put it in the front of the amp.

 

[94Tremoverb]

It probably will color the tone slightly in that buffers reduce loading and improve high-frequency response, but the Boss buffer is fairly transparent, at least if you're only using one of them (you start to notice the change more if you have several in line). At the end of the day *all* effects and pedals color the tone to an extent - in fact, the two MXRs will dull it slightly since they're mechanically-switched non-true-bypass, so the slight brightening from the Boss buffer may help bring it back to where it was. At worst, you'll just have to adjust your EQ on the amp a bit.

If there's still too much tone change, try running both the pedals in the loop of the NS-2 (ie amp Send > NS-2 input, NS-2 Send > MXRs > NS-2 Return, NS-2 Output > amp Return), that way they're buffered both front and back so the amp can't 'see' them at all. It may help with the bleed-through of the parallel dry signal issue too, since the output impedance of the Boss buffer is far lower than 25Kohms so it will give you much closer to a series loop. If this all sounds too technical, just try it both ways and see which sounds better .