(My looper) works great last in (the effects chain), very clear reproduction. However, when I use my attenuator… (while I create loops and play over them) the looped recording sounds awful… flubby, mush…”
If you play multiple loops through an amp that’s distorting it will sound like a mess. Since you mentioned you use an attenuator let’s talk attenuators a bit. These babies allow your amp to run at high power while controlling the level after the speaker jack.
A lot of guitarists love power amp distortion, that’s why attenuators are so cool. They let you run your amp’s power amp section as hot as you want, so the big power tubes and transformers run at or near the max, then you can attenuate, or turn down the volume between the speaker jack and the speaker. Because all guitar amps distort when they reach their limits, an attenuator essentially turns your amp into a big distortion box. Tom Scholz from Boston and Eddie Van Halen used this attenuator trick on their early albums and their tones were great!
I just watched a Pete Thorne video. Pete was demoing a computer plugin that uses impulse responses to simulate different guitar speakers mic’d up with different mics. To do this you plug your amp’s speaker output into your computer audio interface and then the plugin simulates the speaker cab and mic.
Wait!! First, you need to attenuate, or lower the speaker level, or bad things will happen! The power to drive a speaker will melt your audio interface beyond recognition! Your audio interface accepts line level signals, not the power to drive a 4×12 cab. Attenuators usually have not only speaker outputs but also a line level output. In this case Pete plugged his attenuator’s line level output direct into his audio interface to demo the impulse responses simulating speakers and mics. (Btw, check out my podcast interview with Pete, it’s edition 33.)
Now back to looping. If you want to play more than one loop with a looper pedal into an amp you should run your amp as clean as possible and not use an attenuator, or at least very little attenuation. So, turn the amp’s master volume up, and turn your preamp volume very low. Then if you want distortion and effects use a multi FX unit or pedals plugged in before the amp. (Btw, in this case you do not need to use the amp’s FX loop because the amp is running totally clean. FX loops do open up looping possibilities we can cover later.)
Although, over the years I have liked full-on amp distortion, but nowadays there are such good distortion boxes out there that even me, an old school guy, run my amps clean and get my distortion from pedals! I love my Boss DS-1X for rock tones and I also use a Keeley-modded Boss SD-1 for crunch. I love those tones!
The DS-1X is digital and uses computer algorithms to improve on tube amp distortion, making low notes tight and high notes fat. I have a ’90s Peavey 5150 head, it’s the industry standard for metal tones and I think my DS-1X into a good clean amp may sound better.
What I do for looping and looping gigs is, I run a Roland VG-99 direct into a Boss looper, (RC-50) then out of the looper I go into my PA. The VG-99 models tons of guitars and amps, and has every effect I can think of. I can even get bass tones with my guitar! With my VG-99 I could loop a modeled 12 string acoustic along with a modeled Les Paul into a distorted Marshall, using only one guitar. The fully processed tones go into the looper and then out of the looper direct into my full range PA.
If you use looping for practice, the simplest way to do it is to set your amp as clean as possible, then use a distortion and/or other pedals before the looper. Or better yet use a multi FX before the looper. I really dig the new Boss GT-1! (above) That would give you lots of different tones to run into the looper. Then out of the looper go into a clean amp, no attenuation.