how do reverb tanks work

[buildafriend]

fill me in.. passive, active.. buy tank.. build tank? how small are they? I want to integrate one in a valve overdrive pedal

[Mike Burgundy]

They need  a driver and pickup recovery, and they're large. Plus mechanically very sensitive to shocks and vibration - won't break, but you'll hear it since the springs actually carry the soundwaves of your signal, so any shocks intoduced will be very audible. Some surf guitarists used this as an effect, kicking the reverb on purpose.
May be very difficult to reliably cram into a (large) pedal. Standalone units are mostly built into amp-like cabs and switched remotely.
Some reading: (Google is your friend)
http://www.tubesandmore.com/scripts/foxweb.dll/extpage@d:/dfs/elevclients/cemirror/ELEVATOR.FXP?page=TECH_REVERB
and
http://www.accutronicsreverb.com/
Rummage around on the Fender Amp Field guide to see some exapmples of reverb circuits as integrated on amps and standalone reverbs.
http://www.thevintagesound.com/ffg/

[Johan]

how do reverb tanks work?..: practical application of Inertia
for stompbox use, springs are probably not a good idea. but today there are good electronic versions offered by Belton/accutronics that would probably do just fine in a kick-around-friendly format.
I think Smallbear sell "the brick", and might even offer a kit..
J

[joelindsey]

Here's another good read: http://sound.westhost.com/project34.htm

You could build that circuit in a foot-switchable box and place the actual tank in a spot where it wont get kicked or shaken.

Reverb tanks can be around eight inches to a foot and a half long, and several inches wide. Building one would be rather cost-ineffective since can buy really nice MOD reverb tanks (some say they sound better than Accutronics) for around $20.

I had some fun a few days ago connecting an LM386 amp directly to the input of a reverb tank and sending the output to my mixer. 

[boogietone]

All reverb tanks work in a similar manner, whether they are spring, plate, or a room with a speaker and microphone.

1) convert the electrical audio energy to a mechanical energy.

2) bounce the mechanical energy around

3) convert the mechanical energy back to electrical energy.

Reverb is simply a multitude of somewhat incoherent echos that are interpreted by the brain as distance and depth to and around a sound source. The details are in the two conversion processes and the type of mechanical energy being used. The conversions are some kind of transducer, i.e., a wire coil around a metal core that contains magnets. This could be a specifically designed transducer, a guitar cabinet and/or a microphone. In operation, the input driver circuit of the reverb tank feeds the alternating audio signal at an appropriate level and impedance to the coil which causes the metal core to vibrate. The output is the reverse. The mechanical vibrations can be through one or more springs, a suspended metal plate, or just air in a room or even in a pipe or other enclosure that may vibrate in sympathy itself. The "trick" is to use appropriate drivers and transducers for the particular mechanical energy carrier and then to size and dampen the mechanical system to obtain the particular "type" of reverb desired.

It is hard to get a tank in a pedal sized enclosure due to the size of the mechanical system needed to obtain usable reverb.

[buildafriend]

All reverb tanks work in a similar manner, whether they are spring, plate, or a room with a speaker and microphone.

1) convert the electrical audio energy to a mechanical energy.

2) bounce the mechanical energy around

3) convert the mechanical energy back to electrical energy.

Reverb is simply a multitude of somewhat incoherent echos that are interpreted by the brain as distance and depth to and around a sound source. The details are in the two conversion processes and the type of mechanical energy being used. The conversions are some kind of transducer, i.e., a wire coil around a metal core that contains magnets. This could be a specifically designed transducer, a guitar cabinet and/or a microphone. In operation, the input driver circuit of the reverb tank feeds the alternating audio signal at an appropriate level and impedance to the coil which causes the metal core to vibrate. The output is the reverse. The mechanical vibrations can be through one or more springs, a suspended metal plate, or just air in a room or even in a pipe or other enclosure that may vibrate in sympathy itself. The "trick" is to use appropriate drivers and transducers for the particular mechanical energy carrier and then to size and dampen the mechanical system to obtain the particular "type" of reverb desired.

It is hard to get a tank in a pedal sized enclosure due to the size of the mechanical system needed to obtain usable reverb.

Okay understood. Now to sort my options. Where do I get a small digital reverb tank? What are the smallest real spring reverb tanks?

[markeebee]

Check this out too:

http://www.diystompboxes.com/smfforum/index.php?topic=93868.0

[boogietone]

Okay understood. Now to sort my options. Where do I get a small digital reverb tank? What are the smallest real spring reverb tanks?

http://gtresearchnews.gatech.edu/newsrelease/nanosprings.htm is about as small as you can get.

Seriously though, I am not sure how much smaller a reverb tank can get. (Historical note: they used to be very large before they were put into guitar amps).

If you are looking to experiment, I would get a fender style tank off of ebay (10-20 bucks last I looked) and start with that. Try simply cutting the whole thing in half, doubling the springs over, etc. This should "work" but will be unlikely to get the same sound in a smaller size. It is the combination of the length, number, connectedness (note that some tanks have two shorter springs connected together) and the spring constant of the springs and the suspension mechanism of the transducer cores that all work together to get "that sound." It will very likely not scale linearly in size either up or down. Some thoughts are to obtain/make springs half the size of the fender ones but with spring constants around 1/2 and 1/4 of the original ones and go from there.  

[DavenPaget]

how do reverb tanks work?..: practical application of Inertia
for stompbox use, springs are probably not a good idea. but today there are good electronic versions offered by Belton/accutronics that would probably do just fine in a kick-around-friendly format.
I think Smallbear sell "the brick", and might even offer a kit..
J

Well how about danelectro's spring king ? is it a reverb tank ?

[DavenPaget]

All reverb tanks work in a similar manner, whether they are spring, plate, or a room with a speaker and microphone.

1) convert the electrical audio energy to a mechanical energy.

2) bounce the mechanical energy around

3) convert the mechanical energy back to electrical energy.

Reverb is simply a multitude of somewhat incoherent echos that are interpreted by the brain as distance and depth to and around a sound source. The details are in the two conversion processes and the type of mechanical energy being used. The conversions are some kind of transducer, i.e., a wire coil around a metal core that contains magnets. This could be a specifically designed transducer, a guitar cabinet and/or a microphone. In operation, the input driver circuit of the reverb tank feeds the alternating audio signal at an appropriate level and impedance to the coil which causes the metal core to vibrate. The output is the reverse. The mechanical vibrations can be through one or more springs, a suspended metal plate, or just air in a room or even in a pipe or other enclosure that may vibrate in sympathy itself. The "trick" is to use appropriate drivers and transducers for the particular mechanical energy carrier and then to size and dampen the mechanical system to obtain the particular "type" of reverb desired.

It is hard to get a tank in a pedal sized enclosure due to the size of the mechanical system needed to obtain usable reverb.

Okay understood. Now to sort my options. Where do I get a small digital reverb tank? What are the smallest real spring reverb tanks?

Digital ?
http://www.smallbearelec.com/Detail.bok?no=780
Real spring reverb ? ( Not that it's small . )
http://www.smallbearelec.com/Detail.bok?no=510

[slacker]

Well how about danelectro's spring king ? is it a reverb tank ?

Most of the reverb in those is digital, PT2399 based I think. It has springs but they're really just there so you can kick it and make it go boinnnggggg!

[joelindsey]

Well how about danelectro's spring king ? is it a reverb tank ?

Most of the reverb in those is digital, PT2399 based I think. It has springs but they're really just there so you can kick it and make it go boinnnggggg!

I read somewhere that the reverb in the Spring King is from a spring, and the PT2399 is for a subtle slapback echo to make up for the apparent lack of "depth" in the short spring. I could be wrong.

[Mark Hammer]

http://www.swtpc.com/mholley/index.html

or at least here: http://www.diystompboxes.com/smfforum/index.php?topic=48631.10;wap2

[boogietone]

The IMHO best digital reverb is the now discontinued AMT TH-1 Tube Hall unit. Hard to find.

[petey twofinger]

i got a tank out of an old organ , i am curious about a circuit(s) that use a single 9v ps to properly "run" this unit .

[markeebee]

Well how about danelectro's spring king ? is it a reverb tank ?

Most of the reverb in those is digital, PT2399 based I think. It has springs but they're really just there so you can kick it and make it go boinnnggggg!

I read somewhere that the reverb in the Spring King is from a spring, and the PT2399 is for a subtle slapback echo to make up for the apparent lack of "depth" in the short spring. I could be wrong.

Somebody on the other forum added feedback and delay controls - when they're set at min (i.e. no PT2399 delay) apparently there's still a cranky, clanky reverb from the spring.  I keep mine for the boinnnggg.

[petemoore]

 Try the speaker out as a microphone, microphone as a speaker at your own risk. The diaphram-coil-magnet mic may make a teeny 'pip' click you can hear, and a speaker coil, when moving across the magnetic field of course produces an electronic output...in exactly the same way a microphone does [just the diaphram and suspension/structure is different, the basic 'transducer' can serve as an 'air wiggler [speaker]' or a 'wiggled air detector [microphone].
  The coil/magnet can be a generator/motor, the basic concept/structure and properties are present with all coil/mag transducers.
  The spring driver is 'speaker coil' but the cone is 'replaced by a mechanical connection to the spring, the spring drives another transducer at it's other end, producing an electronic analog of the vibes put into the spring. Each transducer has it's set of needs and requires an impedance-match to whatever is driving it, or conversely, whatever it drives.
  Digital is the easiest 'most for a lot less' approach to anything 'delay', preferences vary..I like 'em and can't see why others would find them objectionable, I have tube reverb unit it's gets used in the studio sometimes.

[petemoore]

  Tanks are just long on length and requirements ime. Digitals are fine vehicles to get 'wet' with. Which brings to analog delays..but about 'why' since digital is so easy/inexpensive/tidy ! Why might be about a preferred tone of a certain circuit or BBD and make the trouble involved worth getting over.
  They're each a bit different than the next, so finding the sound might do well to be about finding a sound and working with it.
  I found out reverbs can be particular about where they are, what sound analogs that go into it [and related dynamics/harmonics etc.] as well what produces the sound made from the electronic sound analog [amp and speaker] have a lot to do with which/what/ and getting a particular reverb-tone or close.
  Choosing the reverb for the application makes sense, a little bit goes a long way, and signal definition can be easily lost. A distorting amp/speaker can make a little more added reverb turn into a mush-tone.
  15 put the Fab Echo in my line, while not exactly reverb, but does J. Cash-Slapback and generally is set mild...very nice w/18watter which only accomodates a 'damp' sound when used for cranking amp sound, anything 'wet' makes it lose note definition [unless it's turned down to a cleaner setting]. 

[jefe]

i got a tank out of an old organ , i am curious about a circuit(s) that use a single 9v ps to properly "run" this unit .

Check out the Stage Center project at General Guitar Gadgets:
http://www.generalguitargadgets.com/projects/25-reverb/43-stage-center-reverb

I have no idea if it works, and I suspect the circuit would need to be tweaked to work with different reverb tanks.

[buildafriend]

The general guitar gadgets build for a reverb tank is big. I wish spring reverb fit in a smaller chassis.