[PROJECT] Music Thing Spring Reverb

[Thonk Support]

EDITED NOVEMBER 2017

You want either an Accutronics 9EB2C1B Reverb Tank

OR

Belton BTDR-2H Digital Reverb Brick

Two places I can personally vouch for in the uk

Digital Brick (UK)

Real Spring Tank (UK)

In Germany

Real Spring Tank (DE - Banzai normally pretty quick)

In USA

Real Spring Tank (USA - I have not used this supplier personally)

Digital Brick (USA - Smallbear)

[Tombola]

I just noticed that you coordinated the jumper colour with the PCB.

[Thonk Support]

heheh. yes. Although so anyone doesn't get dissapointed, the 'first pressings' actually come with a super limited Ed. BLACK jumper

So I think the first batch will go for sale on Thursday, Friday latest.

[Thonk Support]

PCBs and Panel sets will go for sale the start of next week once I've broken the back of the kit orders.

[en.]

can't wait to order mine!
any comparison between 9EB2C1B and 8EB2C1B somewhere?

[Jonachi]

Just got two long bricks from the UK supplier! Can't wait to order these kits. Oyeah I need 2 kits (I suppose!).

-J

[Rigo]

Mentioned in other threads:

http://www.tubeampdoctor.com/catalog.ph ... UPQG1J6sG0

Never got to the point of ordering a bigger tank for the A-199, will have to do some ordering now anyway 8_)

[Thonk Support]

It's worth remembering that the tank for the Doepfer sounds *great* with the Music Thing Modular Spring Reverb module.

Whether you like the lo-fi sound of the Doepfer or not, what I've found in a side by side comparison is that the lo-fi nature comes from the Doepfer module NOT the Doepfer tank.

Also I found the difference in sound between the smaller Doepfer tank and the longer 17" version that is often recommended as an upgrade is pretty subtle... and again it's the module that makes 90% of the difference in sound. The only exception really being the decay time, but contrary to popular belief that is not always directly proportional to the length of the tank..

[vurma]

Please keep us updated on the exact time of release. I expect these kits to vaporize pretty quickly and I want in.

[Thonk Support]

I'm pretty sure it's going to be Thursday morning.

[Thonk Support]

SmallBear also have the Brick

http://www.smallbearelec.com/servlet/Detail?no=1211

[Thonk Support]

[Tombola]

Also I found the difference in sound... is pretty subtle...

Second this - I ended up writing a whole bit in the manual about sound:

Using the module, and how to get the best possible sound


I’m very happy with how this circuit sounds, particularly in this demo: But it’s not always easy to coax such smooth tones from a spring reverb.

Don’t assume there is a fault with your module if you don’t immediately get this kind of sound - I made that mistake a few times on breadboard.

Here’s what I’ve learned about getting a good, rich, warm, clean sound:

What you get out depends on what you put in. By far the biggest factor in the tone of the reverb is - obviously - the tone being fed into it. Software reverbs can put the same smooth mushy sound over whatever your run into them. This isn’t like that at all. Remember that it’s a physical system moving about, driven by magnets and electricity and springs.

I’ve found that smooth, clean, FM-ed sinewaves work very well with the springs. On a ‘scope, the output looks similar to the input, but more complicated. On the other hand, square waves try to bash the springs about. There’s no way that a magnet can move a spring in anything like a square wave, so the sound coming out will sound little like a square wave. On a ‘scope, it’s more like a filter or waveshaper.

Small changes in the input sound can be amplified and enhanced by the reverb.

Choice of spring tank is not absolutely critical. Big long six spring tanks will sound bigger than small tanks, but I’ve found that - at least with my limited selection - it is less important than the other factors in this list. I got pretty good reverb from the tiny plastic-boxed new reverb that Belton are developing. You can use EQ to compensate for the choice of tank to some extent.

Hum is caused (and can often be cured) by the exact position of the tank. A reverb tank is not unlike a big, highly amplified single-coil guitar pickup. It will pick up 50/60hz mains hum, particularly from transformers but probably also from dimmer switches or fluorescent tubes. That hum can often be stopped completely by moving the tank away from the source or - often more practically - by just changing the position of the tank. Try shifting it through 90 degrees - on whichever axis is practical - and often the hum will drop. If you want to mount your tank inside a case, experiment with the exact position to find the quietest spot before fixing anything.

Noise (hiss, white noise, not hum) is caused by the high-gain op amp in the recovery section. I’ve tried to reduce it as far as possible by using low-impedance resistors. I also tried two lower-gain op amps in series, which seriously increased the noise. It may be that using other dual op-amps could reduce this noise even further. Or just think of it as tape hiss, adding mojo.

Spring reverb is chaotic and hard to predict. Spring reverb is a strange, gnarly, physical effect. When I tried to calibrate and measure this circuit, I’d find that a sine wave at, for example, 400hz, might barely excite the springs at all, while a sine at 405hz would bust them into fuzzy overdrive. Change a component, and that response changes completely.

[nihilist]

two questions,

When using accu brick, mounted in rear,
what is the benefit of the option B, with front sockets?

Also,
when are these available?

[Thonk Support]

Thursday.

If you want brick only then select the panel with rear sockets, you wont need them although they're still included in the kit.

[Rick Burnett]

Ordered both brick and tank Can't wait to play with this.

[Tombola]

When using accu brick, mounted in rear,
what is the benefit of the option B, with front sockets?

You wouldn't want the phono sockets, but you could - if you like busy panels with incorrect labels - put in two 3.5mm sockets with the EQ Out and 100% Wet out signals. These are unbuffered, so plugging stuff into them could change the way the rest of the module sounds, but it should work OK.

[Stinktier86]

[dupe]

[Stinktier86]

ok.. price for the full kit - 53 GBP (approx 64 EUR / 72 USD)

(GBP + EUR prices include VAT)

That includes everything to use brick and/or spring tank, with either front panel (phonos on front or back) but doesn't include the digital brick or spring tank.

-Does this include vactrols, too?


Already got an a-199 (plus its springs), still figuring out whether i should order one or two kits thurs/fri...

The manual describes 'hacking' the tl072 buffers in order to make the extra outs buffered. Sorry, this will be my first build since i did BYOC pedals/various simple vactrol mods. Someone up for explaining to a newbie?

[Tombola]

The manual describes 'hacking' the tl072 buffers in order to make the extra outs buffered.

If you build the spring but not the brick, there is a space for a TL072 in the brick part of the circuit board. I'd put a socket there, then take a TL072 and fold up (ie horizontal) pins 1,2,3,5,6,7, so only the power pins (4 and 8) stick down into the socket. Place it in the socket to hold steady.

Then, you can create super-simple buffers. Fold & solder pins 1 and 2 together, then do the same for 6 and 7.

Run a signal into 3 (or 5) and it will come out of 1/2 (or 6/7) buffered. You'll have a bunch of ugly wires over the back of your board, so it will look like one of my prototypes.

The pinout is here: http://www.ece.usu.edu/ece_store/spec/tl072.pdf

And you're creating two unity gain op amp buffers: http://en.wikipedia.org/wiki/File:Op-Am ... Buffer.svg

[Stinktier86]

Thanks - made things much more clear!


Additionally, i'm going to vactrolize that tilt potentiometer. Imagine CVed movement on the tilt while using feedback. It's a killer. I've done it with a-199 but i'm imagining the results will be more pleasing since it is a lo/hi tilt rather than the usual high freq roloff.

[Thonk Support]

ok.. price for the full kit - 53 GBP (approx 64 EUR / 72 USD)

(GBP + EUR prices include VAT)

That includes everything to use brick and/or spring tank, with either front panel (phonos on front or back) but doesn't include the digital brick or spring tank.

-Does this include vactrols, too?

yep everything other than the digital brick or spring tank, right down to the rack screws and power cable.

Oh and another little improvement to Thonk kits, the resistors now have the number written on the Bag, R1, R2 etc.

[vurma]

Thanks - made things much more clear!


Additionally, i'm going to vactrolize that tilt potentiometer. Imagine CVed movement on the tilt while using feedback. It's a killer. I've done it with a-199 but i'm imagining the results will be more pleasing since it is a lo/hi tilt rather than the usual high freq roloff.

Hey thats not a bad idea actually. I will have spare vacs since they are included in the kit.

[cane creek]

I'm going for brick but not sure which decay time

Medium 2.5s or Long 2.85s ?

[Thonk Support]

The one in this demo is the Medium, I've not tried the long.

http://soundcloud.com/thonksynth/music- ... lar-spring