Reverb Tank

[hh73]

Peavey Valveking 112:

Stock Reverb Unit:
2EB2C1B (Ruby)
(9 inch, medium decay)

New Reverb Unit:
4EB3C1B (Accutronics)
(17-inch, long decay)

Problem:
Stock unit has stronger/louder reverb than new reverb unit.

Why?? How do I fix this?

[ijustwannastrat]

Without sounding sarcastic, where is your control at? I would think that since it's a physically longer unit, that there would be more reverb, so if you are setting the control in the same place, it's going to be louder/longer.

If that's not the problem, then you need somebody who knows what they're talking about (they should be along soon....)

[sumgai]

stratty, he did say that it was the older, original tank that was louder and stronger, not the new one.....

~!~!~!~

hh73,

I took a look at the charts, and it would appear that the only difference between the two tanks is the decay time. Well, that and the fact that the first digit ('2' for the Ruby unit) isn't valid - that should be only a 1, 4, 8 or 9. But then again, this is a Ruby device, and they aren't required to follow the chart, now are they?

Which then says, if they boogered that figure, then what else did they ignore?

From your description, I tend to believe that you've got an impedance mismatch going on here. Unfortunately, it's not easy to measure impedance, most multi-meters don't have that capability. One way you can test the Accutronics tank is to take it to a Fender amp, and replace the tank therein. In this way you can confirm that it works as it's supposed to, and isn't bad in some way. (I'm referring to a Fender tube amp, preferably a Twin or a Super, something like that. Newer, smaller Fender amps with short tanks are not the same thing.)


One other thing you can try..... You didn't mention if you've tried reversing the two leads. I know, the input and output jacks may be labeled, but are those labels correct? It won't hurt to try it and see what happens.....


HTH





sumgai

[hh73]

I have tried reversing the leads. All I get is a little extra background hiss, but otherwise same performance.

There is no mistake in the numbers I have given for the Ruby and Accutronics tanks model IDs.

It CANT be impedance mismatch, as they are both "EB" tanks.

[sumgai]

Mar 8, 2011 12:59:27 GMT -5 hh73 said:

There is no mistake in the numbers I have given for the Ruby and Accutronics tanks model IDs.

Note that I didn't accuse you of jotting down the numbers incorrectly, I accused Ruby of not obeying the Grand Scheme of things.

Mar 8, 2011 12:59:27 GMT -5 hh73 said:

It CANT be impedance mismatch, as they are both "EB" tanks.

Let's not be getting all defensive now, no one's casting any blame here....

But in point of fact, the problem most certainly can be an impedance mismatch, labels don't mean squat. But I agree, the chances of this are very slim indeed.

Mar 8, 2011 12:59:27 GMT -5 hh73 said:

I have tried reversing the leads. All I get is a little extra background hiss, but otherwise same performance.

Well, a clue at last.

If you've done this with the short tank (that's working as expected), then you know that the above result (with the long tank) is unusual to say the least. Normally, reversing the leads of a tank all but kills the signal. There will still be a huge crashing sound if you disturb the tank physically, but playing your guitar through the amp, with the control turned up.... you should barely hear any kind of reverberated signal at all. Connected right-way-around, you should be in Drips-ville.

What you said about getting the same results no matter which way it's connected tells me something valuable. Either:

a) one of the two transducers has gone bad; or

b) the leads on the inside, from the transducer(s) to the jack(s) are suspect. You might consider wiggling said leads while playing, to see what happens. If you feel like it, you can re-solder them, just to make sure that everything is copasetic.

The proof of the pudding of course is to test with a Known Good Unit. You've done this, with the original tank - that means that the amp, the jacks on the amp, and the cables/leads are all good. The only thing left is the tank itself, and that's why I suggested that you test it in a different amp, one that has the same kind of reverb tank. If the same problem shows up here too, then you know you've got two choices:

1) try to fix the tank itself (the transducers, the jacks, and/or the wiring between them); or else

2) return the tank to the seller. (You didn't say if it's used or new, so this might not be applicable here.)

Sorry I can't be of more help at this time.

HTH




sumgai



(EDITed - restored one of the quotes that had somehow disappeared....)

[hh73]

I bought the tank new on Amazon. The tank was well packaged and insulated when I opened the box it came in from the mail.

I'll try giving them a call now that I have consulted you. Thanks for all your help!

If anyone else has ideas about what might be causing the problem, please POST! =D

[hh73]

I just reversed the wires for my stock reverb unit, and it did not affect performance one bit.

This is totally contrary to what people are telling me should happen.

Ideas??? lol

[sumgai]

Let me be sure of what you're saying here..... If you reverse the Input and Output cables on the stock, original, known-good working tank (labeled as made by Ruby), you still get the same tone, the same amount of reverb, the same everything?

That's not quite in the absurd territory, but it's getting almighty close.


At this point, I pretty much have to insist that you find another amp, preferably a Fender with a long tank, and insert both your new Accutronics unit, and your Ruby unit in place of the standard tank already in that amp. (One at a time, of course.) This will test the integrity of the tanks themselves. And I say this is necessary because your current amp may have an issue of not providing the correct impedance values at the Input and/or the Output jacks.

At the voltage and current levels seen by a reverb tank, these impedance values are critical. That's why an 8Ω input and a 2250Ω output rating should be destructive to the sound, when the leads are reversed. I now suspect that your amp may be using a Ruby tank that has been mis-labeled so that it will work, or at least sound like it's working correctly.

Sorry to be so pessimistic, but that's how I'd conduct further investigations - testing with another amp, I mean. Without that knowledge, we're just playing around, as far as I'm concerned.

<side note>
Discussion of troubleshooting procedures.

In essence, my most trusted method of finding problems is two-fold: The visual inspection stage, where I look at things closely (and I might also use smell and/or touch to find problems); and the stage where I start inserting Known Good parts in place of suspected bad parts. Along side of that is the bit where I place suspected parts into Known Good amplifiers (or guitars, etc.) This helps me to verify that a part is good or bad, and unless the stars are all out of alignment with the Moon, I can usually get it right the first time, without too much hassle.

There's another factor in this equation however, and that is that I try to move along in a linear fashion. That means that I start at one end, and work my way towards the other end. During that process is when I'm investigating both circuits in general, and parts in particular. But take note: I almost never shortcut the process, unless it's something that I have so much experience with that I can't sleep at night, for dreaming of the furshlugginer things. (Opto-isolators in Crate amps are an example here, cheap jacks found in 98% of all amps are another such example.) I try to stay focused on the current step, and then move on to the next step. It helps to do it this way, believe me.   Because the alternative is what we call the shotgun method - you just blast away at anything that catches your fancy, and hope to Gawd that you don't waste too much time, money or energy on the problem.

</side note>

HTH



sumgai

[hh73]

I have just checked by calling GuitarCenter and having them look inside a new amp, and the stock unit for these Valveking 112 amps is a 2EB2C1B, which is what I have. So unless Peavey is lying on all their amps (haha, not likely) the issue is with the Accuntronics unit. I have contacted the seller on Amazon, and I'm getting a replacement for free.

The only thing that matters for reverb units are their impedances, correct? Nothing else matters for compatibility?

Since both the stock unit and the Accutronics unit are "EB", their impedances should be the same. I think I just got a bad unit in the mail from them. If this happens again with the replacement unit they send me, then I know the problem is more likely at my end. Right?