amp guts - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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
Reply
 
Thread Tools Search this Thread
Old 7th May 2009, 02:53 PM   #1
d0n is offline d0n  United States
diyAudio Member
 
Join Date: Feb 2009
Default amp guts

I bought this acoustin control corporation amp recently. It's 200wpc. Dual mono design with a power switch for each channel. I've never seen 2 power switches on one amp before. She's a big heavy beast!

I thought you all might be interested in seeing the guts. If anyone happens to have a rocker power switch let me know! The outside measurements are 1.5" high x 1.25" wide.

Click the image to open in full size.

Click the image to open in full size.

Click the image to open in full size.
  Reply With Quote
Old 7th May 2009, 03:04 PM   #2
diyAudio Member
 
ostripper's Avatar
 
Join Date: May 2008
Location: Albany , NY (smallbany)
Hi, Don. I just seen a rocker like that in the radio shack parts drawer. Worst case , if you know the dimensions , mouser definitely has it .

What a classic (looks like 70's) separate driver boards,each channel forms one half of the "tunnel". (does it work?)
Also , this amp seems to be single supply (no + - , just positive)
with capacitive coupling (blue caps in rear). Just 1 cap per channel.

BTW , worry not ..the stealth is open and on the table. (did you get my email?)
OS
  Reply With Quote
Old 7th May 2009, 03:39 PM   #3
d0n is offline d0n  United States
diyAudio Member
 
Join Date: Feb 2009
Pete, Good eye! It was made between 1974 and 1979. I have powered the amp up but not hooked it up to a source or speakers yet. It does turn on and the fan starts running. No magic smoke came wafting out... so that's a good sign.

I looked through the mouser site at about 50 different rocker switches but couldn't find one with the right dimensions. It's a strange size... 1.5 inches high and 1.25 inches wide (outside bezel size). The switch is a snap in type so the dimensions have to be exact or it won't work. I'll keep looking.


I did get your email. I am not too worried about the stealth. I knew you were busy working on your amp. I just wanted to make sure you were able to get the cover off with those stupid and useless locks on it. The locks are strange. Why would someone put locks on a case to keep someone out? And, they don't even work.
  Reply With Quote
Old 8th May 2009, 07:12 AM   #4
diyAudio Member
 
east electronics's Avatar
 
Join Date: Jan 2006
Location: Athens GREECE
Default with

1800w power consumption .....and 10 transistors per amplifier section your calculation about power is for sure wrong ...

id expect a minimum of 450 W rms at * ohms ...
__________________
SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr
  Reply With Quote
Old 8th May 2009, 02:31 PM   #5
AndrewT is offline AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
I wonder if the model number (400) means 400W per channel?

5pair output stage could indicate 4ohm compatibility. 4A slow blow is just about right for this.

400W into 4r0 requires ~ +-70Vdc or +140Vdc (single polarity)

What's the voltage rating of the larger electrolytic capacitors?
__________________
regards Andrew T.
  Reply With Quote
Old 8th May 2009, 05:41 PM   #6
d0n is offline d0n  United States
diyAudio Member
 
Join Date: Feb 2009
I was originally told that it was 200wpc at 4 ohms.

Recently a collector tells me it is listed as being 375wpc at 2 ohms.
  Reply With Quote
Old 8th May 2009, 10:05 PM   #7
diyAudio Member
 
firechief's Avatar
 
Join Date: Sep 2008
Location: Near Seattle Wa
For the switch, try Antique Electronic Supply
  Reply With Quote
Old 9th May 2009, 08:38 AM   #8
dangus is online now dangus  Canada
diyAudio Member
 
Join Date: May 2004
Location: Vancouver Island
200W into 4 ohms per channel is plausible. Some amp companies rate some of their amps that way. And in the '70s, more than 100 watts was considered high power, and darned expensive. If you have a local university library with back issues of Audio magazine, the Annual Equipment Directory issue may have a listing for those amps.

I'd look carefully at those Molex style connectors... I've had problems with those, like oxidized contacts that overheat and burn up the plastic.
  Reply With Quote
Old 9th May 2009, 09:27 AM   #9
diyAudio Member
 
east electronics's Avatar
 
Join Date: Jan 2006
Location: Athens GREECE
Default do some reading .....

Quote:
Originally posted by d0n
I was originally told that it was 200wpc at 4 ohms.

Recently a collector tells me it is listed as being 375wpc at 2 ohms.
before posting ...... this is out of the question .... at the good times of 70's there was no such a term 4 OHMS or 2 OHMS all amplifiers were refered to power in watts at 8 OHMS

rating amplifiers in 4-2 ohms is >2000 fashion and doesnt mean that is possible or true ....

hypotheticly a today's amp that produces 100W @8ohm will produce 200 in 4 ohm and 400 @ 2 ohm but from existing amps only very few are capable to do that eventhough they state so

especially some of the amps have a new term which is called 2OHM stable ( meaning that is possible to operate in 2ohm but nobody say how much power they will produce )

today all these is mostly comercial tricks .....at the 70's the real power for class AB amps was rated in watts in 8 OHMS

now days we have class D amps that can do things like that but yours isnt any of those
__________________
SERVICE ΕΝΙΣΧΥΤΩΝ ΚΑΙ ΙΑΠΩΝΙΚΩΝ ΜΗΧΑΝΗΜΑΤΩΝ ΗΧΟΥ www.eastelectronics.gr
  Reply With Quote
Old 9th May 2009, 06:21 PM   #10
diyAudio Member
 
Steve Dunlap's Avatar
 
Join Date: Sep 2008
Location: Here
Quote:
Originally posted by d0n
I was originally told that it was 200wpc at 4 ohms.

Recently a collector tells me it is listed as being 375wpc at 2 ohms.

The collector seems to be right. That amp was rated at 275W@4 ohms and 375W@2. That was at 5% distortion. This was a PA amp that listed for $899 in 1977.
  Reply With Quote

Reply


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
Show me your guts! neurot Car Audio 109 12th June 2012 07:27 PM
AD797 guts aparatusonitus Solid State 3 21st March 2008 05:02 PM
Amp Guts Page is Up!! Matt74 Car Audio 5 2nd November 2005 02:56 PM
Car amp guts page Matt74 Car Audio 7 30th September 2005 04:14 PM
spraying the guts of my amp... 9am53 Tubes / Valves 2 20th April 2005 01:25 AM


New To Site? Need Help?

All times are GMT. The time now is 04:46 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