Tape delay. diy preamps / recordering

Hi everyone! been a while… I don’t share too well sorry. So, I’ve been screwing around with eurorack stuff for a bit now… I figured I’d share what I’m up to. I’ve always loved tapes, and I’ve wanted to do a cassette tape delay for some time now. then an idea climbed on in to my noggin, and won’t get out… how about a tape delay module? yup a pint sized tape delay module for eurorack, using a microcassette loop as its core. you think regular cassette loops are fiddly… well. let me show you something. (truth be told its easier to load the loop in a micro, but harder to make the loop)


it doesn’t work well. so far I’m still breaking loops at the joint, and have yet to get it to pass sound, I’m using the boards from the recorders, as building a decent preamp has proved difficult, as even the slightest bit of radio / mains interference is picked up, or at least in my sorta working looper test rig made on a regular cassette recorder. I’ve got some other chips and some Chinese preamps to fiddle with to hopefully make some progress, but its really slow going. anyone have any tips / suggestions for A) making better tape loops, and B) better circuitry… mainly to keep interference out. I’m thinking I could make a faraday cage for it, but that seems excessive.

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Your faraday cage would help. I use copper cloth for awquard shapes.

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Some of the best (and quietist) tape head preamps are made with discrete transistors, check out some of the diy audio forums. Also put the preamp as close as possible to the head and electrostatic screening (Faraday cage) is definitely a good idea too.

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A few months ago I considered building something like this using a bunch of old tape recorders that I have in my parts boxes, but after reading about the intricacies tape head biasing, I abandoned the idea before getting down in the rabbit hole.

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Rabbit hole or JFDI?
Crack on. I knew none of that detail when i began hacking casette reel dicta phones. You can still buy heads and complete management boards for a few quid which are easy to control with an esp32 etc.

Fun low techy loop is to make mobious loops and feed the tape through a gauntlet of playback heads.

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There is something magical about the whole process of magnetic tape recording. Dismantling taperecorders as a kid was kinda my inauguration into the wonderful world of electronics

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Something like this?

Stereo Tape Recorder Magnetic Head Preamplifier Board With CXA1332 Dolby Noise Reduction
https://a.aliexpress.com/_m09qaJm

Looks like you could just hook up 12v input right?

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Yes. Remembering you are not limited to a single format. Ive always wanted to make a pegboard tape delay with brakes, pulleys and tape heads i can move around. Ah, the list!

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Dont know what others think but I really dislike Dolby noise reduction . It chokes the life out of a piece of music, I’d rather here the hiss and let the music breathe.

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Not gonna go there, as i am indebted to the Lord Tuffnel for settling, what we now know to be rock fact, that heavey metal sounds better in “Dobly”.

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…and with all knobs turned up to 11!

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My two cents

  1. Microcassettes are notoriously difficult both to make loops of and then run. But I can see the attraction in the form factor.
  2. Regular-size cassettes are easier to use.
  3. Two tapeheads next to each other make a decent tape echo:
    https://www.youtube.com/watch?v=OYjC2h2sVaE
  4. A tape deck is large but any smaller machine that records could work.
  5. Skipping/replacing the erase head with a permanent magnet will work, but a proper biasing makes for MUCH better / cleaner / louder / recordings.
  6. Example of a Eurorack sized regular cassette size tape looper (not my Youtube but you can see the size clearly here:
    https://www.youtube.com/watch?app=desktop&v=slgkYn9VnlQ
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