What are the advantages/disadvantages of an amp FX loop?

[Thom]

Like the question says, what are the advantages/disadvantages of an amp FX loop?
And do you use one? Or go guitar -> pedals -> amp?

[Mike]

I used to use one but don't now.

Advantages:

You can use your amp overdrive and get more defined dirty repeats on your delay pedals, get dirty swirls on your modulation and use an EQ to really shape the sound before you hit the poweramp.

This means that you don't need to buy a dirt box to hit your tremelo pedal with to get hard shudders if that's what you're after.

Disadvantages:

FX loops will affect the tone of your normal signal often, as they add extra buffering and circuitry into the signal path which can load things down - if you're using a series loop then your signal is only going to be as good as your worst bypassing pedal (the effect of a poor bypass is amplified because of the direct injection into the Power Amp stage).

You need two more cables and this can be a mess on stage.

There's more but that's off the top of my head. My philisophy is taht if you can do without then more power to you.

[euan]

What Mike said.

The only place where I'd imagine using an effects loop was when:

1) I loved my amp's dirty sound
2) My amp didn't have reverb
3) I wanted reverb on my amp's dirty sound

And just like Mike said effects loops are post pre amp pre power stage, so even in this situation it would only be partly effective in giving me the sound I'd want. But that's why you get parallel effects loops and you get mix controls.

Some people think they are great, others can't think of a way to use them.

[Thom]

Cool, cheers guys.
I don't use mine either, was just curious as to when you might want to use one.

[Doog]

I go guitar>pedals>amp personally, but I always run my amp clean, so it's not a problem.

One thing I read about the Marshall TSL series (I think) is that they have a footswitchable FX loop and an FX level dial. If you connect the FX loop up with a patch lead, and turn the level up, you've got yourself a solo volume boost option from the amp footswitch. I'd imagine there's a bit of signal degredation like Mike said, but could be pretty cool.

I've not played a TSL or tried that though, just going from something I've read.

[Mike]

I go guitar>pedals>amp personally, but I always run my amp clean, so it's not a problem.

One thing I read about the Marshall TSL series (I think) is that they have a footswitchable FX loop and an FX level dial. If you connect the FX loop up with a patch lead, and turn the level up, you've got yourself a solo volume boost option from the amp footswitch. I'd imagine there's a bit of signal degredation like Mike said, but could be pretty cool.

I've not played a TSL or tried that though, just going from something I've read.

Unfortunately the TSL effects loops make the tone of the amp change to be plasticy and bad.. which is crap. My amp has a switchable series or parallel loop with trimmable FX level. I have never fully explored it though, I find my pedals work great up front. The MDX cuts through overdrive like butter.

[euan]

Effects loops to mix match pre and power amps anyone?

[Mike]

That's another use for them but it only works in the case where the effects loop is serial, and then you'll see it labelled as:

Send/Preamp Out
Return/Power Amp Insert