2 channel custom 50 combo - fx loop hiss

[gdmiller88]

Anyone else with a 2 Channel Custom 50 have a lot of hiss when using pedals in the loop? It's bad enough that it's unusable. I'm hoping it's just a bad tube, but wanted to see if anyone else was having this issue. I've been reading a lot about the Archon having this problem.

 

[Dusty Chalk]

It does sound like a bad tube -- the loop does have its own tube in most PRS models of which I am aware.

 

[László]

Some pedals will interact with a lot of noise in a loop, and some loops would rather see a line level signal, such as from rack gear, while some would rather see an instrument level signal, such as from pedals.

The first thing to do, however, would be to see if the noise is coming from the amp or from the pedals. I'd check with PRS to see what they recommend as to how to go about this.

 

[andy474x]

Put just a short cable in your effects loop - that should be a pretty easy test to diagnose if it's something in your chain pedal-wise, or something in the amp.

Regarding Les' comment on the line level signals, I've also had that problem. More manufacturers are starting to add a switch to their amps that takes the signal down to an instrument level, including the discontinued PRS SE amps. Personally, I would rather have the switch than the adjustable dials that USA PRS amps have, it's just so easy. I'm sure there are reasons to have the fine adjustment too, I just don't need them. And it's all about me!

Any amp maker that's still making a fixed, line level loop is committing a crime, IMO. Seems like the vast majority of players are using pedals, not rackmount stuff. But maybe I'm missing the big picture. After having my PRS amp, I will be HIGHLY resistant to ever buying an amp that doesn't have an instrument level loop, and bias test points. C'mon, do we all REALLY need to be paying $50-100 to get our amp biased every time we change tubes, when we could just get a multimeter at Radio Shack for $20?

Sorry for the rant.

 

[László]

Put just a short cable in your effects loop - that should be a pretty easy test to diagnose if it's something in your chain pedal-wise, or something in the amp.

Regarding Les' comment on the line level signals, I've also had that problem. More manufacturers are starting to add a switch to their amps that takes the signal down to an instrument level, including the discontinued PRS SE amps. Personally, I would rather have the switch than the adjustable dials that USA PRS amps have, it's just so easy. I'm sure there are reasons to have the fine adjustment too, I just don't need them. And it's all about me!

Any amp maker that's still making a fixed, line level loop is committing a crime, IMO. Seems like the vast majority of players are using pedals, not rackmount stuff. But maybe I'm missing the big picture. After having my PRS amp, I will be HIGHLY resistant to ever buying an amp that doesn't have an instrument level loop, and bias test points. C'mon, do we all REALLY need to be paying $50-100 to get our amp biased every time we change tubes, when we could just get a multimeter at Radio Shack for $20?

Sorry for the rant.

It's a good rant.

I think there are touring pros, though, that need line level loops for their racks of doom (yes, they're still out there with lots of players, including guys like Gilmour, etc!) and the adjustability is a nice feature. But a good loop should ideally work for both. The only issue is that pedal makers (and some rack gear makers) adhere to no real standard, so there are always possibilities for noise to exist.

As for me, well, I'm so old school that I've given up on loops altogether and just want to run everything in front of the amp.

That's because I'm old, in addition to being old-school. In fact, it's probably why I'm old-school.

 

[Dusty Chalk]

Put just a short cable in your effects loop -...

Excellent suggestion -- it would eliminate the tube, if nothing else.

And yes, I could see it being -- for example -- a mismatched impedance between an effect and the loop out/loop in, instead of the tube. There's probably a way to fix that if you're married to the pedal with some sort of impedance matcher.