tirsdag den 20. august 2013

Spring Reverb Module

After a nice long summer holiday with plenty of time for contemplation and relaxing, I felt it was time to return to the workshop and strike while the soldering-iron was hot so I finally finished my spring reverb module which had caused me some headaches during the spring time (no pun here). During trouble shooting, I've learned a lot about operational amplifiers which will be useful in future builds.

Here's the finalized contraption in action!



It's basically a Spring Reverb Tank (the ones you find in old guitar amps) for which I've made an amplifier-circuit. The 'IN' knob controls the gain for the signal sent into the spring, the 'DRY' knob lets through some of the clean signal to the internal mixer circuit and the 'WET' knob sets the gain for the signal from the spring tank to the mixer. This lets you just plug one jack-cable into the module and adjust how much of the clean signal you want to blend with the reverbed sound - saves a lot of cable mess. The input gain acts as a kind of "decay time" as it somewhat determines how long the spring will vibrate for because of the amplitude sent to the spring.

I also found out that you can get nice feeding oscillations if you turn off the input sound! (happens in the end of the video)









I feel this is kind of a 'must have, must build' module for anyone serious about having a handmade modular setup, so I was very determined to get this done and now I am so relieved about finally having this mo-fo boxed and good to go so I can focus on the larger projects I am about to unveil for you good folks out there!

Here's my scheme for the amplifier-circuit:


I chose to use seperate ICs to avoid bleeding of the signals, which I encountered on the test-board. I see that I didn't bias the mixing stage, but it sounds good without.

12 kommentarer:

  1. Hi, sounds very nice. Can this work for guitar? I imagine the input / output impedances would need to be changed to work.

    Hej, lyder meget rart. Kan dette arbejde for guitar? Jeg forestiller mig, input / output impedanser vil skulle ændres for at arbejde.

    -Jeff

    SvarSlet
  2. Hi
    Sorry my poor english
    Can you tell me the tank reverb model you get this spring reverb?.
    I need to know it because the input impedance is not equal in every tank reverb
    Thanks for your time
    Regards

    SvarSlet
  3. Hello
    Im using scavenged part so do you think i can use UPC4062C insted TL082
    http://www.alldatasheet.com/datasheet-pdf/pdf/80467/NEC/UPC4062C.html

    SvarSlet
  4. I also have http://www.promelec.ru/pdf/la4700.pdf and http://fi.mouser.com/ProductDetail/NJR/NJM4556AL/?qs=sGAEpiMZZMtCHixnSjNA6NG6IBDWSupw2032v%252bpfgaw%3d and http://www.datasheetlib.com/datasheet/735272/ym3428_yamaha-corporation.html do you think i can use any of these chips. And sorry to bother you

    SvarSlet
  5. I would love to purchase one of these from you - please contact me if this is possible. robviolajr@gmail.com thanks rv

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  6. Where do you attach the ground? Thanks!

    SvarSlet
  7. Please can you give us the vero layout?

    SvarSlet
  8. Did we can use any spring tank ?

    SvarSlet
  9. I just built it, but it didn't work.... Must pin 8 of the EL072 connected to the +9v? How Can I test each op amp? Thanks a lot!

    SvarSlet
  10. can i purchase one of these from you? amazing sound... or could i get a parts list and " how to build" instructions .. any info would be great ! many thanks

    SvarSlet
  11. my email is Merrickadams@hotmail.com

    SvarSlet
  12. Hi, I built it yesterday, unfortunately when I played it, the springs didn't engage at all. There was just the dry sound with lots of hum, I don't know why. Should I solder the 9V minus anywere on the ground line? I also read there is difference between input and output impedance between various spring tanks. I have some basic 2-spring old Peavey grounded spring tank, don't know which model yet. Thank you for any info:) Please keep up the good work, I hope some day I'll have better understanding of this all.. milanriha123-at-gmail.com

    SvarSlet