Old Olympic audio tube amp - diyAudio
Go Back   Home > Forums > Amplifiers > Tubes / Valves
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

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 29th March 2006, 10:52 PM   #1
24kilo is offline 24kilo  United States
diyAudio Member
Join Date: Aug 2005
Default Old Olympic audio tube amp

Just bought a Olympic SA-812, I can't find anything on it. It has one 12AX7 and two 50C5's. I just changed the caps and it sounds great...But I want to use it for my Guitar amp and would like the Schmatics so I can mod the front end for overdrive. Any Help? Or can you tell me how this tube Config is laid out? BTW here's a pic

  Reply With Quote
Old 29th March 2006, 11:39 PM   #2
diyAudio Member
Join Date: Apr 2004
Location: Monroe Township, NJ
Based on the word "Stereo" on the front panel, I'm going to guess that there are 2 single ended channels using a 12AX7 section driver and a 50C5 "final".

The 50C5 data sheet suggests that the amp uses a series heater string and doesn't have a power transformer. That's both cheap and DANGEROUS.

Perhaps the best thing to do with that unit is canabalize the O/P "iron". Turning it into a safe guitar amp is probably not in the cards.
Eli D.
  Reply With Quote
Old 29th March 2006, 11:47 PM   #3
24kilo is offline 24kilo  United States
diyAudio Member
Join Date: Aug 2005
I should have said, Sorry it's Mono. It says Stereo but it mono. The Speakers are inside. I've already grounded the chassis and no more floating ground.
  Reply With Quote
Old 30th March 2006, 01:51 AM   #4
diyAudio Member
Tom Bavis's Avatar
Join Date: Jun 2002
Location: Macedon NY
OK, I have good news... and more good news.

First, I'm holding the schematic in my hand - a scan will cost you an email...

Second, it actually has an isolation transformer in it (assuming it's the same as the SA-813 and 814...) so it's somewhat safe...

...and some bad news - you'll need another tube to get enough gain for a guitar - maybe add a 12AV6 or 12AU6?

  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
OT for audio but still tube Andrewbee Tubes / Valves 1 12th August 2008 04:29 PM
A new audio tube HollowState Tubes / Valves 50 23rd December 2006 05:41 PM
car audio tube amp answer??? JZatopa Car Audio 0 21st January 2006 04:07 AM

New To Site? Need Help?

All times are GMT. The time now is 10:49 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2