Putting delay and reverb before or after your amp's breakup

I spent a good few years on the bench telling customers the same thing before I even looked at their amp: "where's your delay pedal plugged in?" More often than not, that was the actual problem, not the amp at all. Get a cranked EL34 power section into proper breakup and stick your ambient effects on the wrong side of it, and you'll spend hours chasing a mud that was never the amp's fault.

This one trips up more players than pickup height or string gauge ever will, and nobody talks about it enough. So right then, let's sort it.

The basic rule, and why it exists

Delay and reverb almost always want to sit after your dirt, whether that dirt comes from a pedal or from the amp's own preamp and power tubes breaking up. Put a repeat or a reverb tail into distortion, and the amp reprocesses every single repeat as if it were the original note, fuzzing them out into a smeared, indistinct wash. Put the delay after the gain stage instead, and each repeat stays a clean, discrete echo of the note you actually played, decaying naturally.

This is straightforward when your dirt is a pedal on the floor in front of a clean amp. It gets a lot less straightforward the moment your dirt is coming from the amp itself, cranked into natural sag and breakup, because now there's no "after the distortion" point on your pedalboard. The distortion is happening inside the chassis.

Why an effects loop exists (and it's not just marketing)

This is exactly what an amp's effects loop is for. A proper series loop taps the signal after the preamp gain stages but before (or in some designs, as part of) the power section, so your time-based effects go in after the tone has already broken up, not before. I've had customers convinced their effects loop was "broken" because their delay sounded thin in it, when actually it was working exactly as designed. The confusion happens because ambient effects react so differently front-of-amp versus in the loop that people assume something's faulty.

An amp like the Marshall DSL40CR (check price) or the Blackstar HT Club 40 MkII (check price) gives you a series loop for exactly this reason. Run your gain-stage pedals (or use the amp's own dirty channel) and keep your delay and reverb in the loop, and the ambience sits behind the breakup properly, each repeat distinct, the reverb tail transparent rather than swampy.

Smaller combos without a loop, the Blues Junior IV (check price) for instance, don't give you that option, so you're stuck putting everything in front. Honestly, that's fine for lower-gain blues tones where the breakup is gentle. It falls apart faster the harder you push the front end.

Where it actually falls apart

Ambient and post-rock players run into this constantly, because the whole point of that sound is big trails and swells sitting under a gained-up tone. If you're chaining something like a MXR Carbon Copy (check price) or a Strymon TimeLine (check price) in front of an amp that's already cranked, you get a wash of indistinct mush the moment the repeats start piling into the gain stage. I've heard players blame the pedal, blame the amp, swap both out, and never actually fix anything, because the problem was never the gear. It was the order.

My honest opinion, and I'll cop some argument on this: most bedroom ambient rigs would sound better with less delay feedback and more attention to loop placement than they currently get. Everyone reaches for another repeat before they reach for the effects loop. Wrong order of priorities, in my book.

Working without a loop

If your amp doesn't have a series loop, you've got two honest options. First, keep your gain modest enough that the amp's own breakup isn't smearing the repeats too badly, this is basically how the blues and classic rock guys got away with running everything front-of-amp for decades on amps like a cranked Vox AC15C1 (check price). Second, get your distortion from a pedal instead of amp breakup, run that pedal first, then delay and reverb after it, all still in front of the amp, with the amp itself kept clean or near-clean. The ProCo RAT 2 (check price) or a Tube Screamer (check price) into a clean-ish valve tone works fine this way, because the amp itself isn't adding a second layer of unpredictable dirt on top of your repeats.

Reverb specifically, a small note

Reverb behaves slightly better in front of breakup than delay does, because a wash of ambience getting a bit of extra grit isn't as obviously wrong to the ear as discrete, countable repeats turning to fuzz. That's why a lot of players get away with a Holy Grail Nano (check price) or Hall of Fame 2 (check price) in front of a pushed amp for years without noticing an issue, while the same placement wrecks a delay pedal's repeats. If you're only running reverb, front-of-amp is far more forgiving. Add delay into the mix and the loop question becomes worth solving properly.

Setting it up in practice

Get your dirt tone sorted first, on its own, whether that's amp breakup, a pedal, or both. Then bring in the delay and listen specifically to whether the tails are staying clean and discrete as they decay, or turning fuzzy and losing pitch definition. If it's the latter and you've got a loop, move the time-based pedals there and A/B it. The difference is usually obvious within about ten seconds, not subtle at all once you know what you're listening for.

Our guide to the best delay pedals covers a few units with proper trails modes worth knowing about here, and if reverb's your main focus the reverb pedal guide is worth a read too, mixing algorithmic and spring-style options that behave differently loop versus front-of-amp.

The bit people forget

None of this matters if your amp's power section isn't doing anything interesting in the first place. A lot of players chase loop placement and pedal order for months while running a solid-state or heavily digital amp that doesn't actually sag or compress the way a valve power section does, so there's no real breakup to place anything around. If that's you, have a look at what a proper EL34 or 6V6 power amp does under load before you spend more money on pedals. It changes the whole equation.