FX loop/blend based on the Paralooper inside

[therecordingart]

So I created a thread yesterday looking for some insight on the Paralooper. After staring at it for a little while and thinking about my needs and different IC based buffers, I came up with something a little different. This isn't verified yet, and I'm sure there are parts additions and subtractions that can or should be made. This is based around a single quad opamp with an output stage that is variable between a gain of 11 and unity.

The bias resistors can be changed to values of your liking as can C2, C4, and C7. (Keep the values of the bias resistors equal to another). Changing the resistors will vary your input impedance and the caps your low frequency response. What value of caps would provide the best bass response? I need to do some math! I just started with common values.

Here is the schematic and Eagle file. You'll need the Gaussmarkov library for Eagle. The only thing I ask of you is that if you create a PCB, perf, or vero layout please make it available to everyone in this thread. Also, if you make any changes to part values or the layout of the schematic please provide them in this thread and the reason for the changes. You can never learn enough and every bit of insight is important.

Schematic:
http://dl.dropbox.com/u/8772719/DIY/FXLoop/FXLoop.png

Eagle file:
http://dl.dropbox.com/u/8772719/DIY/FXLoop/FXLoop.sch

[therecordingart]

I was just thinking about adding a means for switching between an inverting or non-invertaing stage in the FX send/return section. I'm not sure how many pedals are out there that have an inverted output, but that could cause some issues blending a signal that is 180 out of phase with the dry signal.

Maybe I'm over thinking it?

[B Tremblay]

I was just thinking about adding a means for switching between an inverting or non-invertaing stage in the FX send/return section. I'm not sure how many pedals are out there that have an inverted output, but that could cause some issues blending a signal that is 180 out of phase with the dry signal.

Maybe I'm over thinking it?

http://runoffgroove.com/splitter-blend.html

[therecordingart]

I was just thinking about adding a means for switching between an inverting or non-invertaing stage in the FX send/return section. I'm not sure how many pedals are out there that have an inverted output, but that could cause some issues blending a signal that is 180 out of phase with the dry signal.

Maybe I'm over thinking it?

http://runoffgroove.com/splitter-blend.html

Well crap.

At least I learned something whipping this schematic together.

[pinio]

Here is main.

and second

Project based on mostopamus paralooper. Both have regulated hi-pass filter on loop, and lo-pass filter on clean. Second have added attenuator on loop send. Its for old fuzz, which sound better on hi-z and lower input signal.

On Monday i can put schema witch marked changes.

[karter2000]

Just bumping this as I'm interested in the schematic!  I've built a paralooper as well, but I've wanted to put filters on the clean and effected sides.

[earthtonesaudio]

Yet another splitter/mixer circuit, I called this one "Return to Sender":

[pinio]

http://www.moosapotamus.net/THINGS/paraloop/paralooperSCH.gif
http://www.moosapotamus.net/THINGS/paraloop/paralooperTT.gif
http://www.moosapotamus.net/THINGS/paraloop/paralooperLYT.gif

Replace C6 - 22nF (can be lower for example 15nF) , R7 - paralel 22k and pot 1M, this realize hi-pass.
Replace R6 with pot 5k (4k7), optionally C5 with bigger - up to 100nF.

If You want attenuator on Send on 2 lug pot 470k, 1 lug - ground, 3 lug - Jack socket, R5 - 1M.

Is this clearly?

[karter2000]

Loud and clear!!