[Deigh]

I'd like to build a small cheap 12v reverb unit to add to my guitar amplifier in New Zealand. Quite prepared to work from a kit. In fact I'd prefer a kit but cant find anything on the internet. Anyone got any ideas?

 

[(*steve*)]

Someone posted this earlier today.

https://www.electronicspoint.com/2-ring-modulator-t244736.html

Maybe it's useful.

 

[Deigh]

sorry, you got me there, what is a ring modulator?

 

[(*steve*)]

I have no idea. But the effect sounded something like reverb. I thought the term may have been more familiar to you. <shrug>

 

[davenn]

I havent used a ring modulator outside of RF activities...
In that situation, it is a way of applying audio modulation to the oscillator to produce an FM signal out.

above is a standard ring modulator usually housed in a metallic package for shielding.

In the case of the OP's guitar effect, the input would be from the guitar, the output to the amplifier and the carrier would be an input from a fixed or variable oscillator

I have no idea if they make then specifically for audio freq's, not something I have had anything to do with. But now you have an idea on what its about, maybe you can do some more google searching etc and see what you can find.

If you find some possible circuits, show them to us guys and there's sure to be some one that can say "yup that looks ok" or "no its a load of crap"

cheers
Dave

 

[Deigh]

I havent used a ring modulator outside of RF activities...
In that situation, it is a way of applying audio modulation to the oscillator to produce an FM signal out.

Thanks for that, gives me an idea on how to build one.Will continue searching the internet and see if anything turns up. I can buy a professionally built one but they are expensive, large and do too much. All I want is something to make the output from my amplifier sound a little more interesting when playing solos.

 

[Raven Luni]

I didnt know a ringmod could be used for reverb - but the simplest way to make a reverb unit is to use a spring - has to be fairly long and flexible and has a magnetic coil at each end - 1 to drive it and 1 as a pickup. These obviously need the correct amplification at each end and optionally you can add some filtering. It's been on my list of things to do for years - I actually have a spring and coil set from an old amp that caught fire.

 

[Deigh]

I didnt know a ringmod could be used for reverb - but the simplest way to make a reverb unit is to use a spring -

Yeah, did consider this and started to look on the internet for one but realised that there is no room left inside the amplifier carcase! I have added three batteries to the one that was there initially, put in a mass of wiring so that I can read the condiditon of each of them from the outside, added four cigarette lighter sockets so I can charge each battery independently by plugging into the campervan 12v domestic system, and recently added a plastic box to hold the jack plug lead. There just aint any room left! The whole unit has got so heavy that I have installed a weight balancing device so I can lift the unit into and out of the camper without getting a hernia!

 

[alfa88]

PT2399

Goggle search for a PT2399 datasheet. I used the schematic in the application guide and it worked extremely well. You can tweak some values to get more range. Someone out there made a kit including a compander stage.