Reverb tanks?

[Phil_S]

Thanks for everyone's comments. Lots of useful information here.

I think my original plan of building this amp into an orphaned organ chassis is the right one. Inner dimensions are about 9.25" x 12" (235x305 mm^2). My thinking is that the wide cab won't be so ready to tip over if I need to make it 12" high. This does, however, beg the question of whether to use a 16.75" tank (a bit longer with the bag) or go for a smaller form factor, if I can find one for the tranny. LOL, I'm thinking the head cab for this one will be made with 10" (9.25" nominal) lumber, measuring about 19" wide and 12" high. It will be odd looking but workable.

Next question. Is there anything special about reverb cables? Ordinary coax RCA type connectors, ground the sleeve, tip is hot? I've got some laying around maybe from the 60's or 70's. This will be my first reverb build. I'm starting to realize, I don't even know all the questions just yet.

Yes, I have an orphaned foot switch...that can do both the reverb and the tremolo.

[renshen1957]

Hi Phil

"It is curious, I contacted the current Korean Accutronics organization directly and they provided pricing and payment details. Then I contacted the USA distributor, who, in an odd kind of way, cautioned against buying substandard Chinese copies of the Accutronics tank but the information on an actual purchase was not that helpful."

Accutronics was sold to Belton, who was already producing Korean knock-offs, offshore production of tanks for OEM.

"There are also some murky details about whether the Belton equivalent (same Korean company also bought Belton) is the same thing or different."

The major consensus is that the Belton Accutronics (Korea) does not sound the same as NOS Accutronics USA, and both sound different than the Korean Belton non-accutronics label.

As to construction the new construction Korea Accutronics are different construction to the NOS US Accutronics but the same construction as as non-accutronics Korean belton tanks.

The MOD Tanks are made for AES/CE Dist. are made in China, and supposed to sound tonally similar to the US out of production tanks.

Meanwhile, some searching on the internet took me to one forum where they seemed to really like the MOD reverb tanks. It was skimpy on details, but at least a couple of people seemed to think the MOD tank was better hardware and more faithful to the original design.

I wonder how this is going to affect Fender's claim of Made in the US amplifiers as more and more components can be traced to offshore?



Physical Comparison:



NOS Accutronics These tanks are the industry standard. They were marked as made in the USA.

unpainted steel chassis

panel mount phono jacks riveted to outer channel

phono jack shell is grounded to reverb tank outer channel by surface to surface contact

3 spring units have all transmission springs laid out in one single plane
phono jack terminals connect to transducer coils via small two pin plug connector

Accutronics® (Korea)

Accutronics® was purchased by Belton. These tanks are currently made in Korea with Accutronics® equipment.

black painted steel chassis
panel mount hooded phono jacks clamped into outer channel via plastic housing

phono jack shell is grounded to reverb tank outer channel by a tab and self tapping screw driven into the chassis

3 spring units have all transmission springs laid out in one single plane
phono jack terminals connect to transducer coils via small two pin plug connector


MOD™

Is a trademark of CE Distribution (USA). These tanks are currently made in China to vintage Accutronics® specs.

black painted steel chassis
PC mount phono jacks riveted to outer channel
phono jack shell is grounded to reverb tank outer channel by two PCB copper pads and their soldered connection

3 spring units have transmission springs laid out in two planes
phono jack terminals connect to transducer coils via direct wire taps


Belton (Korea)

Belton is a Korean electronic components company that also makes the Digi-Log Reverb Module.

gray painted steel chassis

panel mount hooded phono jacks clamped into outer channel via plastic housing

phono jack shell is grounded to reverb tank outer channel by a tab and self tapping screw driven into the chassis

3 spring units have transmission springs laid out in two planes

phono jack terminals connect to transducer coils via direct wire taps


I have attached a Sound Characteristic Comparison:

The NOS description has a difference, it is the only one that doesn't use the word "bite" in it.

I have a MOD tank for an upcoming project, I have been able to compare it as of yet to the Made in the US tanks.

Best Regards,

Steve

[LeftyStrat]

I bought two to use in the Craig Anderton Hot Springs Circuit. Here's a pic:

[renshen1957]

I bought two to use in the Craig Anderton Hot Springs Circuit. Here's a pic:

Hi,

How did the CA Hot Springs circuit sound?

Best Regards,

Steve

[LeftyStrat]

I haven't got around to completing it, I hope to finish this weekend. Everyone I've ever talked to that owned one loved them. They all suggest the sound is closer to plate reverb than spring reverb. I guess whether that is a good thing in a guitar amp is debatable. Obviously if you're looking for surf twang, it might be a bad thing.

I just wanted to try the circuit with a longer tank than the ones Paia sells. I also plan on upgrading the 4136 quad op-amp used in the original circuit with something a bit higher quality. I have some OP275's on hand, and some Burr Brown op amps on order.

These tanks are the same input and output impedance as the Paia ones. The model number is 4FB3A1B.

I'll try and post clips when I'm done.

[M Fowler]

I started using the MOD reverb tanks when the Accutronics were no longer available. Nothing wrong with the sound of the MOD tanks.

Mark

[Bill Moore]

I built one of the PAIA kits back in the early 80's, seems they were using the OC tanks then, (built by beautiful Wisconsin girls). I used it on our vocal mains, and it sounded great. Interesting to see what the 4 series tanks will sound like. (Even with the supplied IC's, the noise wasn't noticeable).