When do you use Send/Return ?

[Ngr]

never

[Jazz Noise]

Pretty much only if you want reverb or delay before your amp distortion.

I'm more of a pedal man so, no, never!

[Boschen]

Never; I prefer to use those options when running live sound at the console, and then almost always for vocals; maybe a comp on the bass or drums sometimes. I've never been a fan of heavy rack gear paired with an amp either; boat-anchors, most of 'em. I prefer to get an amp that can produce a real tone on its own. External processors? Meh. I'd rather have one really good tone than a truckload of crappy processed sounds.

[litepipe]

I've never liked the sound of going through send and return. I always use pedals right infront of the amp.

[Joe P]

A looper! I love being able to quickly throw down a clean rhythm track and kick up the gain and work on soloing over it. If you have your looper in front, that would dirty up your rhythm track.

[HeimBrent]

Delays sound better in the loop, in my experience. The standard is putting time-based effects there, especially if you use your amps distortion.

[Altered Beats]

Generally speaking, the fx send is a preamp output and fx return a power amp input, which means that you can use them if you want to use the power amp of a certain head with a different preamp in front, etc.

[verve92]

Buy a Digitech RP500 or 1000.
It allows both.
I always use the RP in live situations. I can use the pre amp in my Fender amp and also use the Digitech's stomp box loop which allows you to also have your pedals as well either pre or post.
Almost like a Bradshaw switch. But there is nothing wrong with putting pedals in directly though. Best thing to do is experiment.....
Here is a great demo:

[Iggy Poop]

Everyone thinks I'm overboard but I like to hear my delay, reverb, and modulation effects (chorus, tremelo) all through my fx loop. I think they sound cleaner. Everything else goes in front of the preamp. Just my ear's preference.

[BLUElightCory]

Originally Posted by HeimBrent

Delays sound better in the loop, in my experience. The standard is putting time-based effects there, especially if you use your amps distortion.

This is exactly what I do.

To me, delays, reverbs, and modulation sound cleaner and have more depth when inserted into the loop. You can still put them in front of the amp for a grittier tone.

[HeimBrent]

It's just basic effects-stacking. If you like your dirt before your modulation, and you're using your amp set dirty, you'll need to have the modulation in a loop to get the sound you like.

I talked gear with a guy once. He said he hated the sound of his delay before his dirt, and that he wasn't to happy about his sound at the moment. For some reason he hadn't really thought it thru. Guitar -> boost -> delay -> distorted amp... I tried to tell him, and he concluded that he couldn't be bothered putting the delay in a loop. It's two bloody cables. 20 bucks. It's not expensive, and it's not a hassle. Color-code the cables and get one of those wraparound-things, and takes half a minute more to set up.

[verve92]

Originally Posted by HeimBrent

It's just basic effects-stacking. If you like your dirt before your modulation, and you're using your amp set dirty, you'll need to have the modulation in a loop to get the sound you like.

I talked gear with a guy once. He said he hated the sound of his delay before his dirt, and that he wasn't to happy about his sound at the moment. For some reason he hadn't really thought it thru. Guitar -> boost -> delay -> distorted amp... I tried to tell him, and he concluded that he couldn't be bothered putting the delay in a loop. It's two bloody cables. 20 bucks. It's not expensive, and it's not a hassle. Color-code the cables and get one of those wraparound-things, and takes half a minute more to set up.

Good advice. You should just give it a shot.

[Janne19691]

Only reverb. I prefer everything else before amp. I specially dislike delay in the loop.