Acoustat servo amp help needed - diyAudio
Go Back   Home > Forums > Loudspeakers > Planars & Exotics

Planars & Exotics ESL's, planars, and alternative technologies

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 24th December 2010, 04:58 PM   #1
diyAudio Member
Join Date: Dec 2010
Default Acoustat servo amp help needed

Hi all, bringing some Acoustat X's out of a long retirement (put em in a closet in 1981 )

What is a modern op-amp, and where do you get them?

Also, looks like a bad tube took out a 10K 5w resistor, and I read in the service manual I should change it and a 10K 15w one as well.
Can anybody point me to a supplier for these?

Many thanks in advance! and happy holidays to all!

  Reply With Quote
Old 24th December 2010, 05:34 PM   #2
diyAudio Member
Join Date: Feb 2009
IMO, the best place to start is to contact Michael Savuto at Analogue Associates. He specializes in the Servo amps. (AFAIK, they work on nothing BUT the Servos.) You can either send the amps to him to work on, or purchase parts from him if you're handy with electronics. He has upgrade parts that were selected (& some specifically made) for the amps, for both sound quality & reliability. I can't afford it now, but I plan on doing a complete overhaul of my Servos, eventually. The people that have done his upgrades seem to be unanimously blown away by the improvements. Mike is a good guy, too. Very helpful. is the address.

Good luck!
  Reply With Quote
Old 26th December 2010, 02:46 PM   #3
diyAudio Member
Join Date: Dec 2010
Thank you, I may end up taking that path.

Right now, I'm still on the DIY hunt ... hoping someone can recommend an op-amp and a good on-line source for electronic parts in general. (I'm OK with a soldering iron and basic circuit testing.)
  Reply With Quote
Old 26th December 2010, 03:59 PM   #4
diyAudio Member
Join Date: Feb 2009
Savuto does have upgraded replacements for the opamps in the Servos. The most recent price sheet I have lists the price of the quad IC + new socket at $30. He also has a more advanced version which requires a bit more work & parts.
  Reply With Quote
Old 27th December 2010, 02:15 PM   #5
diyAudio Member
Join Date: Dec 2010
And another thanks!

Still hoping for a few op-amp suggestions....wouldn't mind experimenting..
  Reply With Quote
Old 27th December 2010, 04:24 PM   #6
diyAudio Member
Join Date: Feb 2009
According to the schematic I have, the original op-amp is an LF347N. Per a conversation with Savuto about a year ago, I recall there ARE a number of functional equivalents, and that they had tried a bunch of different models before settling upon the one they thought sounded best and which they sell as a straight replacement. Their higher level op-amp mod actually does away with the quad unit entirely.

If you need a schematic, I can help you out. Best of luck, be sure to let us know the results of your testing!
  Reply With Quote
Old 11th January 2011, 05:54 AM   #7
gootee is offline gootee  United States
diyAudio Member
Join Date: Nov 2006
Location: Indiana
Blog Entries: 1
Mouser Electronics - Electronic Component Distributor

Electronic Components Distributor | DigiKey Corp. | US Home Page
  Reply With Quote
Old 13th January 2011, 09:57 AM   #8
ktuuri is offline ktuuri  Canada
diyAudio Member
Join Date: Nov 2007
Give Michael Savuto at Analogue Associates a call, he has resistors and Opamps you can buy and DIY. I have got some parts off him in the past. The Opamp that he sells is a very good upgrade over the stock pieces.
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
FS B & W Model 802 and Acoustat TNT 200 ronrzes Swap Meet 1 9th October 2008 08:32 PM
Acoustat Trans Nova Twin TNT 200 schematic needed WolfgangL Solid State 1 4th June 2006 06:30 PM
CD46 Servo info needed Fidelity Audio Digital Source 0 25th May 2006 01:18 PM
Acoustat X amp schematic Milo Tubes / Valves 18 10th April 2003 02:56 PM

New To Site? Need Help?

All times are GMT. The time now is 12:14 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2