How hard is a spring reverb unit to make?

...and how to do so...
KVRer
24 posts since 22 Mar, 2021

Post Tue Jun 22, 2021 12:07 pm

I want to make a spring reverb unit, but I'm a beginner so I was just wondering if this is a realistic goal.

User avatar
KVRAF
13023 posts since 8 Mar, 2005 from Utrecht, Holland

Post Tue Jun 22, 2021 1:38 pm

With a DIY kit? Sure, go ahead, have fun!
From scratch and no experience? No way.
We are the KVR collective. Resistance is futile. You will be assimilated. Image
My MusicCalc is back online!!

KVRAF
13043 posts since 13 Oct, 2009

Post Tue Jun 22, 2021 5:34 pm

It's not that hard, but it's probably too hard for a first DIY project from scratch. In simple terms, a spring reverb tank has a coil that acts like a speaker on one end, and a coil that acts like a microphone on the other end. So, if you have a reverb tank, you drive one end with a small amplifier, this is really nothing more than a simple op-amp buffer, and you put another simple amplifier on the output to boost the signal and then mix the signal coming out with the incoming dry signal. That's it.

It's one dual opamp and a collection of passive parts. I built the circuit from the Fender blues junior, schematic below, into a little amp project of mine and it worked just fine with the reverb tank that I had on hand.

If you can read this schematic and sus out the reverb circuit and make sense of it, you're probably ready, if not, as BertKoor advises, go with a kit.

https://www.thetubestore.com/lib/thetub ... ematic.pdf

Here's a kit:

https://paia.com/proddetail.php?prod=6740K

User avatar
KVRAF
11469 posts since 7 May, 2006 from Southern California

Post Wed Jun 23, 2021 11:00 am

There are quite a few spring reverb kits, some geared toward guitar amps and others more studio oriented.
I think the difficulty depends on your expectations. If you expect to have a quality reverb by the end, go with a kit. There aren't a lot of components, so mechanical assembly will be the most difficult part.

If you only expect to explore and have fun with the project, then try starting from scratch and just see how far you can get. As ghettosynth mentions, the electronic part will be pretty simple and may only require a dual opamp IC and a few passive parts. But from there you could try making your own op amps from discrete circuits. It's also a lot of fun to play with using different materials (different types of springs, sheet metal instead of springs) and different types of transducers (dynamic mic elements, speakers, piezos, etc).

KVRer
2 posts since 26 Jul, 2021

Post Sun Jul 25, 2021 9:34 pm

I built one of the Paia reverb kits many years ago, still use it regularly, it's very good!

User avatar
Beware the Quoth
29903 posts since 4 Sep, 2001 from R'lyeh Oceanic Amusement Park and Funfair

Post Mon Jul 26, 2021 1:50 am

I know this is a wee bit necro'd but just for some future diy/lofi explorer:

The venerable Nic Collins provides some info on making crude spring reverbs from Slinkys and the like in the following pdf

https://www.nicolascollins.com/texts/TapeOpReverb.pdf

If I remember rightly, there's similar info in his book HandMade Electronic Music, which is now on its 3rd edition.
successfully and consistently snarky

Return to “DIY: Build it and they will come”