Hand-written note with Kurt's settings for the Electro-Harmonix Polychorus, new version of the 1977 Echoflanger, (for Heart-Shaped Box and Radio Friendly Unit Shifter):

ehx.com/blog/ehx-tone-tips-the-sound-of-nirvana

From kurtsequipment.com:

Effects:

10). Electro-Harmonix EchoFlanger (32)(40) and Electro-Harmonix PolyChorus (37)(seen at various photographs/concert footage.).

Despite the different names, the Polychorus and Echoflanger had the same internal circuitry. Kurt supposedly only had one EchoFlanger, despite what is said in (32). Kurt used the EchoFlanger on the Brazil shows (source info? Rio perhaps?) and the song "The Priest They Called Him" (found on various bootlegs, etc.). Both pedals were taken on the "In Utero" tour.

The EchoFlanger sometimes "acted up" and Earnie gave Kurt his PolyChorus as a back-up. This PolyChorus was used on "In Utero" for the "Heart-Shaped Box" solo, "Radio Friendly Unit Shifter," and "Scentless Apprentice" (41). Earnie sent out another PolyChorus to Kurt, hoping to get his back, but the "new" one broke and was given to Eric Erlanderson of "Hole" who had it fixed. Earnie did eventually get his PolyChorus back, but not before Kurt marked his settings on it with nail polish and put Velcro on it.

The EchoFlanger was supposed to be used on "Unplugged" but caused too much 60-cycle hum in the control room. Courtney now has Kurt's EchoFlanger (40).

Sources mentioned:

32). "Guitar World" magazine (and possibly also a later issue for the item mentioned in parenthesis under the "Recording of 'Nevermind'"). March 1995.

37). "From the Muddy Banks of the Wishkah," album. (DGC) 1996. Photos from insert and cover.

40). My phone conversation with Jim Vincent, NIRVANA's tour tech from later 1993 through all of 1994. 1/28/97.

41). Chris Lawrence's Equipment Tutorial which also contains information from Earnie Bailey, Kurt's main guitar technician.

Featured in this March 19, 2020 Facebook post.

😉

one of my favorite devices from the early eighties is this Electro Harmonix Echoflanger. this is the original one I used on so many records from 1981 onward. it’s missing the all-important 4-way selector knob so it can’t be made active, but I have another in much better condition I bought from mike at Analog Man years ago which works perfectly.

you can see the “dot settings” I put on it, one of which would be the “elephant sound” for “elephant talk”, one of which would be the “rhino sound” for “lone rhino”, and another of which would be the guitar sound for “genius of love”.

I discovered by accident the one thing I love most about it. the missing 4-way knob was faulty and could be made to “stick” between settings. sticking it between “chorus” and “flanger” was the way I made the sound for “genius of love.”

my very favorite sound I made with it started by sticking it between those settings, but then came the fun. if you carefully adjusted the “feedback” it would start to oscillate. then you could fiddle with the “tune”, “width”, and “depth” knobs to create the sound of giant metallic insects flying across the stereo image.

in the 80’s I had it mounted on my mic stand so I could get that sound to “stick” and then manipulate the knobs to create my crazy oscillation effects. one of the music magazines in japan had a cartoon of me doing just that with me looking like Frankenstein!

I used that sound many times on record (I still do). to hear it, listen to the ending of “Gypsy Zurna” on “Desire Caught By The Tail”.

(don’t have that record? it’s available for download of bandcamp.)

I’m just sayin’.