Reverb tank swap

[mrbrown49]

Question for those that have swapped reverb tanks:

 

I'd like to upgrade the tank on my ampeg J12t. Problem is, I can't find the exact unit I need, but I can find one that's close. The difference being that the one I need ideally has the input insulated and the output grounded. The one I can find has both the input and output grounded. Is that a deal breaker?

 

Also, I've tried contacting accutronics and apparently you can't order direct from them anymore since they were bought by belton.

[WRGKMC]

Hold on, you missed the key item. Reverb units come is all different impediances from 4 ohms to thousands of ohms. One size does not fit all. They also run on different currents and voltages.

How a tank physically connects is a fairly low priority. Its a hi z cable in and out. Direct solder or RCA are pretty common but even adding some connectors to plug in is simple stuff.

 

You can use a meter and get a ballpark on the coil resistances like you do with speakers and you should be OK. The only other item is the physical size and how many springs used. Many are two spring and others use a Z or W spring folding to get a compact size. Tube driven reverbs will have a different impediance in comparison to transistor drives so get that first.

 

 

Acutronics makes a huge variety of tanks. Go gere and click on a unit that looks like yours and you'll find the various specs. http://www.accutronicsreverb.com/prodspec.htm

 

The best thing you can do is get a direct replacement from the manufacturer. maybe Emailing these guys may help. Otherwise a copy of the Circuit diagram can help to make a wise decision.

[mrbrown49]

Well the tank that's in there is an accutronics tank, but it's one of their budget tank models, type 1. I have the part # of the old one and know what the correct impedance specs should be. The only part I can't match up is the grounding scheme of the IOs.

 

So essentially I want the same part number, except starting with an 8 instead of a 1 (8BB3C1A). The only parameter I can't match up in currently available tanks is the grounding.

[WRGKMC]

The chassis is ground in nearly every tank I've ever seen. The tank shields the thing from hum and is common to both the in and out reverb elements. All you're left with is the input and output wires from the elements.

 

The two wires to the coils will have a hot and ground. if I remember right Black is ground and white is hot. The wires goung to the RCA jacks will have a ground and hot. Since the coils are small transformer like deals you can reverse them and it wouldnt make a big deal. The wires coming from your amp may be the problem you're speaking of.

 

If you had say a single 5 conductor coming into a tank I could see it being a problem. If you were to crank it up with the springs exposed amd the reverb running, you could figure out which is the transmitter/speaker element and which one is the reciever/Mic element. Then you just figure which wire colors are which.

[mrbrown49]

I think I've found a replacement! It's a small amp, but a full length tank will fit in the bottom of the cab. So I'll have the right impedance, grounding config, and a much better quality tank. I checked out the schem and I'm pretty sure that if both sides were connected to ground it would create a ground loop, which may or may not be a problem.

 

It'll be a tight fit, but there should be just enough working room to get it positioned and mounted. Once again, thanks for taking the time to lend a hand.