Here's a question for repairmen...

[Bob M.]

For guys who have repaired alot of amps:
Let's say hypothetically a customer comes in with a Blackface Twin Reverb (mid 60s) or a very early Silverface Deluxe Reverb (or both) and he wants a new reverb tank installed to replace the faulty/ non-working one in his amp(s). He doesn't want the tank repaired; he wants a brand new one (the customer is always right) and he doesn't want a reconditioned one or an expensive NOS one. He knows there are also alot of great alternatives like really good sounding reverb pedals and rack mount stuff but he wants his amp reverb working as it was in its stock condition, with a new reverb tank. Now, of the currently made reverb tanks being offered, which one would you recommend to sound the best and closest to the reverb tank originally in this/these amps(s).

Now, I know all reverb tanks are most probably made in Asia and none probably sound quite as good as a Hammond, Gibbs or an American-made Accutronics tank but in the interest of getting the customer's reverb in his amp up and running again, which reverb tank make would you pick or recommend (or are all Asian reverb tanks absolutely the same sounding in your opinion)? Again, let's hypothetically assume the tubes and parts (and cables) in the drive and recovery parts of the reverb circuit are all working perfectly and it's up to only having a good sounding reverb tank to finish things for this customer. Let's try to keep this hypothetical on point, if possible. I think we're talking about a 4AB3C1B tank here.
Thanks,
Bob M.

[g1]

I think the general consensus here has been that for the discerning customer, you have to pick an individual tank, even within a particular brand. So brand is not a deciding factor, but whichever brand you choose, you need to order several, and pick the best one for your particular unit.
For myself, I have found the MOD tanks to be decent sounding.

On a side note, I have seen a bit of oddness with regard to the tanks corresponding with Fender part #'s, and do not assume them to match up with traditional tank codes anymore.

[xtian]

I get Accutronics and MOD tanks from Antique Electronics, and have noticed that individual tanks of the same brand and model number sound different. Mostly just fine. Some gems, like the one I put in my Deluxe Reverb build. I love it!

[Bob M.]

Xtian,
And the make of the reverb tank you put into your Deluxe Reverb build was...???

[The Dude]

I'm going to make a hard left here. I would have a look at the existing tank anyway, despite the customers wishes. If it's just a simple repair, for instance just a wire broken from the RCA jack, I'd show the customer the problem and try talking him into keeping the old tank. There's not a better way to keep the reverb sound he likes than keeping the tank he likes, and he needs to be aware of that. If the tank can't be economically repaired, then you go to plan B- replacing it.

[Bob M.]

Dude,
I appreciate your post but I'm really soliciting opinions from experienced repair people on what currently made reverb tank brands/makes comes closest to what might be found in an older Fender amp with reverb.

In this particular situation, I think the customer was experimenting with a plutonium-powered nuclear soldering iron he invented which completely destroyed the transducers, springs and jacks. According to his geiger counter, he told me this reverb tank won't be available for repair for another 150 years or so. I told him to leave that tank at home and I'll find another.

All the best,
Bob M.

[The Dude]

In that case, I'm with xtian. I've had the same experience where, "individual tanks of the same brand and model number sound different". It's a bit of a crap shoot. I've used different brands of tanks (MOD, Accutronics, others) with mixed results. All have worked, some with minor modification. The question of "What is the best sounding reverb tank?" is very subjective. What one player likes, another may not. If the customer is that picky and likes what he had, I would stick with the same brand and same part number as what was in the amp.

[galaxiex]

I'm not a pro repair guy, but I have built and modded several tube and SS amps.

I have been very happy with the MOD reverb tanks I've used.

I have an original 79 Silverface Deluxe Reverb with original tank to compare to, and in one case,
The SS amp I installed a MOD tank in, has subjectively "better" reverb sounds than the Deluxe.

YMMV

[xtian]

Xtian,
And the make of the reverb tank you put into your Deluxe Reverb build was...???

MOD.

[Chuck H]

I've had my least bad experience with the MOD tanks. As to sound quality I'll second g1's observation. I've resigned to buying two tanks when I need one and have found myself buying a third on two occasions. More so than sound quality I've had trouble with microphonic sensitivity and noise. Which also seems to be variable unit to unit within a given brand. I've typically had to take measures to isolate the tank further than just a bag. Like wrapping the tank in memory foam before sticking it in the bag. One guy I built for wanted a three spring long delay tank. That bag looked something like a football by the time I got it stabilized. As to noise I've found that the quiet spot for the tank isn't always as straight forward as you think it will be. I've had to modify grounding schemes, ground speaker frames and once even had to mount a tank on the lower rear baffle rather than the bottom of the cabinet to find a quiet situation for various builds.

EDIT: For the purposes of this thread I am not a repairman other than hypothetically

Though I have built a few amps with new reverb tanks and replaced a couple of tanks in older amps.

[Leo_Gnardo]

Like most of the correspondents here I've found MOD tanks to be the best of the current offerings. AND yes, some unit to unit variation. Some 30 years ago when there was a lot more repair traffic here I used to buy Accutronics, a dozen at a time. One customer learned about this and asked me to let him select his favorite out of the next dozen batch, so I let him have a go at them and he came away satisfied he selected the best one to suit his ear. Can't have that kind of selection any more here, but that doesn't mean other people can't do the same.

Similar to Chuck, on rare occasion I've had to mummify a tank in foam to get it to behave in a particular amp. The "old standard" Fender amps somehow never seem to need this treatment. I use foam weatherstrip tape intended to install between camper tops and pickup truck rails. I find it at Home Despot, a nice big roll for about $10 last time I scored any. Cover ALL sides including ends. The tank steel re-radiates sound energy into the springs, and if you can stop the steel panels from vibrating in those frequency bands that are picked up by the springs, you can get a reverb to behave itself in those (thankfully rare) amps that require this treatment.

For the last several years of USA manufacture, Accutronics tanks, to put it bluntly, sucked. The sound quality went to hell and so did reliability. One customer went through about 7 tanks over the course of 2 years or so in the early 2000's. Yes he was mighty annoyed and so was I. At that time I found RUBY tanks, which look an awful lot like the MODs we see now. I have a feeling they are really one and the same. In any case, they obviously worked better than Accujunk so from about 2004 onwards I had a better source of reliable tanks than Accutronics. The current Accu's made by Belton in Korea, I wouldn't bother with them either. Not at all impressed. not in any positive way.

[Chuck H]

For the last several years of USA manufacture, Accutronics tanks, to put it bluntly, sucked. The sound quality went to hell and so did reliability...

I don't know anything about Accutronics in those years. If they changed hands or outsourced any processes, etc. But...

I read that the special weshel compound they used for gaskets on the spring connectors in their transducers became unavialable due to regulations and it's extreme toxicity. And that it was the only thing that would provide the right amount of damping and long service life. Experiments with other materials never worked out and they eventually gave up trying. That's what I read. I never fact checked it but you can if you like. But I agree that Accutronics tanks were terrible in that era. I actually have tried the newer east Asian made tanks. They seem fine. I used one in a build that sounded good so I tried one for the next and it just wouldn't behave and sounded too thin. I ended up with a MOD tank on that one and haven't bought another Accutrincs tank. Since I build customs I like the mod-able grounding scheme on the MOD tanks and their performance has been more consistant than the Belton or Accutronics in my limited experience.

[Greg_L]

Is it just me our do modern tanks have way too much decay? I've handled a decent amount of vintage spring tanks. They have a sound, no doubt. The modern equivalents sound darker and have way too much decay IMO. They're good, sound good, work fine, but the decay....too long. I opt for a medium or even short decay new tank most of the time.

[nevetslab]

Like xtian, I too generally buy my replacement tanks from Antique Electronic Supply in AZ.....often Accutronics, mostly MOD, but also have to go searching for the Ruby tanks elsewhere. I will normally try to restore the existing tank by repairing the broken lead wires, often having to remove the IDC connectors that have the sig or gnd wire broken off up there, and then tack-solder the prep'd leads to those pins, after verifying I have nominal DCR on the tank coils.

I'm very interested in repeating Leo_Gnardo's damping treatment to the sides & ends of the steel enclosure hear how that changes the character of the tank/internal spring system.

I still haven't taken the time to revise the overly aggressive Reverb Return level on the Fender Twins, Deluxe Reverbs and others as there is SO LITTLE MARGIN on the Reverb control before you're producing Surf Music style reverb. Shame the locking suspension mechanism that used to be a feature on the tanks was eliminated, but then....how DO you get at those functions when the tank is mounted on the back of the inside grille panel of a Marshall amp or on the floor inside the vinyl pouch in Fender amps and the like.

These tanks continue to break due to no locking mechanism of the internal suspension of the tank spring assy.

But yes, there is a wide range of tanks that just do suck, and yes, I've heard that variation from amp to amp (of the same tank brand) when I have to deal with the large rental fleet of amps of all brands and colors to keep them working.

[xtian]

Is it just me our do modern tanks have way too much decay? I've handled a decent amount of vintage spring tanks. They have a sound, no doubt. The modern equivalents sound darker and have way too much decay IMO. They're good, sound good, work fine, but the decay....too long. I opt for a medium or even short decay new tank most of the time.

"too much decay" -- do you mean the reverb time is too long? I agree. I buy "short" decay tanks when possible.