Pioneer Reverb-Reverb Tank Replacement

craigmorris74 · 30th July 2005, 12:59 AM

I recently aquired a Pioneer SR-101 spring reverb. The reverb tanks on the unit are in bad shape, and I am looking to replace them. I am looking at Accutronics tanks:
http://www.accutronicsreverb.com/prodspec.htm
Type 8 fits the description of what I need. However, I have no idea what input impedence, output impedence, and what connectors (see bottom of the Accutronics page) are needed for this unit.
A schematic for the SR-101 can be found here:
http://www.angelfire.com/ky3/craigor...chematics.html
Thanks in advance to anyone who can help.

Craig

brianroth · 30th July 2005, 07:43 AM

Measure the DC resistance of the input and output coils in the defective tank, then find an Accutronics that matches it as closely as possible.

As far as the I/O connectors, I assume there are RCA sockets on the broken tank. The next questions are whether or not the "shell" of the RCA socket is grounded to the chassis or are floating.

I just went through that same exercise on a Roland "Chorus Echo" box.

Bri

craigmorris74 · 30th July 2005, 02:54 PM

Bri,
Thanks for your help. I'll measure and see what I get.
Craig

dharma one · 31st July 2005, 03:23 PM

ive been trying to do something similar but vice versa- using accutronics driver schematics with a hammond spring tank.

i initially thought the dc resistance would be quite close to the impedance at 1khz but looking at this chart

they appear to be quite far off. theres a way of measuring the impedance with a test tone, multimeter and 50k pot but i cant remember it off hand..google should find it

brianroth · 1st August 2005, 07:24 AM

The DC resistance should still be a useful "single point" for comparison. DCR and impedance at 1 kHz will be VERY different. However, Hammond, Accutronics, etc used very similar "recipes", so DCR should get you into the ballpark.

Bri

craigmorris74 · 4th August 2005, 03:37 AM

I just got back to my studio and opened up the unit. Behold the impedence is marked: input 1.5 K and output is 2.2K.
The replacement tank I'm looking at has 1.925K input impedence and 2.575 output impedence (this is the best match I can find). Will this tank work, or will I have to add other parts to match the impedences.

Thanks again,

Craig

brianroth · 4th August 2005, 08:27 AM

Craig, probably close enough for rock n roll!

Bri

davemoog · 4th April 2008, 06:51 AM

I've just purchased one of the vintage tube reverbs and am having a problem with one of the tanks. The coils in both tanks measure identical resistance. The tubes seem to amplify and drive equally, yet one of the tanks is quite a bit weaker in output. It almost seems like a problem in the lamination if that is possible. I was wondering if low level was what you were finding or were the coils in your tanks simply open resistance.

And another question how did yours work once you replaced the tanks? Any part numbers handy?

Thanks for any help you can provide.

Dave

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
When is a vocal reverb not really a reverb?	alexis	High end	28	21st November 2007 08:00 PM
Digital Stand alone Reverb vs Plug-in Reverb	SoundUniverse	So much gear, so little time!	29	16th August 2006 08:12 PM
Reverb Tank	slaves666	High end	4	15th October 2005 04:08 AM
Single Spring Reverb tank	Ghede	So much gear, so little time!	9	24th March 2004 05:28 AM

30th July 2005, 12:59 AM	#1
craigmorris74 Gear maniac Join Date: Jul 2005 Posts: 202	Pioneer Reverb-Reverb Tank Replacement I recently aquired a Pioneer SR-101 spring reverb. The reverb tanks on the unit are in bad shape, and I am looking to replace them. I am looking at Accutronics tanks: http://www.accutronicsreverb.com/prodspec.htm Type 8 fits the description of what I need. However, I have no idea what input impedence, output impedence, and what connectors (see bottom of the Accutronics page) are needed for this unit. A schematic for the SR-101 can be found here: http://www.angelfire.com/ky3/craigor...chematics.html Thanks in advance to anyone who can help. Craig

30th July 2005, 07:43 AM	#2
brianroth Lives for gear Join Date: May 2005 Location: Oklahoma City Posts: 1,022	Measure the DC resistance of the input and output coils in the defective tank, then find an Accutronics that matches it as closely as possible. As far as the I/O connectors, I assume there are RCA sockets on the broken tank. The next questions are whether or not the "shell" of the RCA socket is grounded to the chassis or are floating. I just went through that same exercise on a Roland "Chorus Echo" box. Bri __________________ Brian Roth Technical Services Oklahoma City, OK www.BrianRoth.com

1st August 2005, 07:24 AM	#5
brianroth Lives for gear Join Date: May 2005 Location: Oklahoma City Posts: 1,022	The DC resistance should still be a useful "single point" for comparison. DCR and impedance at 1 kHz will be VERY different. However, Hammond, Accutronics, etc used very similar "recipes", so DCR should get you into the ballpark. Bri __________________ Brian Roth Technical Services Oklahoma City, OK www.BrianRoth.com

4th August 2005, 08:27 AM	#7
brianroth Lives for gear Join Date: May 2005 Location: Oklahoma City Posts: 1,022	Craig, probably close enough for rock n roll! Bri __________________ Brian Roth Technical Services Oklahoma City, OK www.BrianRoth.com

30th July 2005, 02:54 PM	#3
craigmorris74 Gear maniac Join Date: Jul 2005 Posts: 202	Bri, Thanks for your help. I'll measure and see what I get. Craig

31st July 2005, 03:23 PM	#4
dharma one Gear maniac Join Date: Jan 2005 Location: manchester UK / helsinki Posts: 160	ive been trying to do something similar but vice versa- using accutronics driver schematics with a hammond spring tank. i initially thought the dc resistance would be quite close to the impedance at 1khz but looking at this chart they appear to be quite far off. theres a way of measuring the impedance with a test tone, multimeter and 50k pot but i cant remember it off hand..google should find it

4th August 2005, 03:37 AM	#6
craigmorris74 Gear maniac Join Date: Jul 2005 Posts: 202	I just got back to my studio and opened up the unit. Behold the impedence is marked: input 1.5 K and output is 2.2K. The replacement tank I'm looking at has 1.925K input impedence and 2.575 output impedence (this is the best match I can find). Will this tank work, or will I have to add other parts to match the impedences. Thanks again, Craig

4th April 2008, 06:51 AM	#8
davemoog Gear interested Join Date: Apr 2008 Posts: 2	I've just purchased one of the vintage tube reverbs and am having a problem with one of the tanks. The coils in both tanks measure identical resistance. The tubes seem to amplify and drive equally, yet one of the tanks is quite a bit weaker in output. It almost seems like a problem in the lamination if that is possible. I was wondering if low level was what you were finding or were the coils in your tanks simply open resistance. And another question how did yours work once you replaced the tanks? Any part numbers handy? Thanks for any help you can provide. Dave

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes	Rate This Thread
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode	Rate This Thread: