| PeterBGood |
| I have a friend that is looking for a schematic for the Counterpoint SA-7 preamp. He has a unit that is in parts and he wants to upgrade it. Any help on this? |
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| fdegrove |
Hi,
Unfortunately I have copies of some other Counterpoint preamp schematics but not the SA-7.
If no one can help you out you could always ask Michael Elliot.
He's the brain behind the Counterpoint gear and is still supporting most of what was previously produced:
ALTAVISTAAUDIO
Cheers,;) |
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| serengetiplains |
| Thanks for the Alta Vista Audio link. I wondered what happened to Counterpoint. Their products seemed to me well built, with decent execution etc. Then they vanished. Could it be but, ah, yes, their bank, of course, got nervous, and pulled the plug. |
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| pedroskova |
Mr. Elliiot is a very nice and unselfish man.
I hope that his Alta Vista entrerprise is going swimmingly. |
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| pedroskova |
| ps - i'm pretty sure that you can purchase the schematic from him. |
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| fdegrove |
Hi,
| quote: | | Their products seemed to me well built, with decent execution etc. |
Oh yes, those were fine products indeed.
My first commercial preamp was a SA-5. Michael Elliot was one of the first to use automatic bias in preamps, gridleak bias on the less expensive models as well.
If ever any of you come across a dirt cheap second hand SA-11 preamp, give me a ring.... :angel:
My own top of the line preamp was inspired by that model but I didn't quite dare to push it that far though.
Cheers, ;) |
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| rfbrw |
| At $75+shipping, the manuals are a bit steep. BTW anyone got a schematic for the SA-3000 TIA. |
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| serengetiplains |
| Oh, my, I remember wanting an SA-11 many years ago as a graduate student, but my budget allowed only for a used c-j PV-5. Mr. Elliot certainly was ahead of his time. |
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| analog_sa |
A bit of an understatement. I wonder why this site is so popular - the upgrades and all services seem to offer dismal value for money.
Send me a PM for the SA7 circuit. I once used to have it and still keep a reasonably detailed circuit (took me no more than an hour of staring at the board to draw it). No PSU as it looked like a textbook emitter follower. |
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| burnedfingers |
Quote:
At $75+shipping, the manuals are a bit steep. BTW anyone got a schematic for the SA-3000 TIA.
Quote:
A bit of an understatement. I wonder why this site is so popular - the upgrades and all services seem to offer dismal value for money.
Gentlemen.... The price may seem a little high but when you stop to consider the time and energy involved in designing/building the units its a bargan in my humble opinion. You could always get out Mr. Longhand and draw the darn thing yourself.:D
Joe |
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| anatech |
Hi all,
At the risk of starting a fire storm, I'll make a comment here.
I was authorized warranty for Counterpoint right to the end. There are many basic circuit flaws in his designs, power supplies seem to be the worst. The SA-9 is just waiting to blow.
His equipment did sound very good preamp wise. There were some really good concepts in design.
Having said that, if you pay attention to decent parts, upgrade the wattage on the plate resistors if they are discolouring you will be fine. Get some decent tubes in and listen to it before going further.
I am in the process of redesigning the SA-100, and have one sounding great. This is still evolving. You should have seen the serious design errors in that thing.
As far as the charge for schematics / manuals go. They are grossly over priced. They have always been way over the top for pricing. Oh yeah, he really did match the output fets incredibly tightly. He had no choice with no source resistors!
analog_sa, that's one I don't have. I agree totally with you on "the upgrades and all services seem to offer dismal value for money." comment.
-Chris |
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| warjarrett |
| If anyone has a schematic for an SA-3 or SA-5.1 preamp, I would VERY much appreciate a copy emailed to me at WarJarrett@aol, thanks in advance. --Warren |
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| GRollins |
Back when I was in retail we had Counterpoint for a period. Pathetic gear. Setting aside sound quality, there's no denying that the stuff was junk, design-wise.
We had an SA-3 (single spaced rack mount preamp, yes? I think I've got the model right). A resistor got so hot that it burned the paint right off the lid of the chassis. (From memory, I think it was a 5W resistor running at around 4.8 or 4.9W Pd.) Called Counterpoint to express concern. The guy insisted vehemently that the part was within spec and that it was normal for it to run "warm." When we noted that burning the paint off the top was more than warm, the guy got really, really angry and started yelling. Hung up on us.
Needless to say, we dropped the brand like a hot potato.
I was sooo not surprised when they folded.
Grey |
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| stoolpigeon |
There were at least 2 versions of the SA7. I think the earlier type had a very shallow chassis with the tubes all on a pcb mounted behind the front panel while the later type used a bigger chassis with the line stage mounted across the back panel and the phono stage along the LH side.
They were quite well made and sound ok but I have to agree with the comments on Altavista pricing. |
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| anatech |
Hi Grey,| quote: | | When we noted that burning the paint off the top was more than warm, the guy got really, really angry and started yelling. Hung up on us. |
:clown:
That had to be Michael! :D His idea of parts running within spec was such a joke! As you noted, he hasn't a clue what derating is. Mind you, I understand someone else did the very earliest designs. This does sound like M.E., he hasn't changed much. BTW, he designs by ear. He even admitted that.
Hi stoolpigeon,| quote: | | There were at least 2 versions of the SA7. |
They were both the same physically. He changed tubes and added an auto mute. The earlier one was completely manual I believe. Could be wrong here, but that is what I recall.
-Chris |
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| stoolpigeon |
I don't have them handy, but yes, the one in the bigger case has an auto mute.
Also, I think on his site he mentions a version with an output fet but I haven't seen this one. |
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| anatech |
Hi stoolpigeon,
He used a BUF03 in many of his SA-2000 and higher preamps. He also used it for the output buffer of his phono section.
Great idea, poorly executed. Now he pulls them (and keeps them) to remove the solid state sound. I bet he has some BUF03 line stages now.
-Chris |
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| stoolpigeon |
| I just checked the web site and the buffer is mentioned as a prior upgrade. Charging to put it in and then charging to take it out - nice work if you can get it! |
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| GRollins |
Just for giggles, I hit the Alta Vista link above. He wants to charge you $100 to make sure your Counterpoint doesn't run hot.
Gee...I can't imagine why anything made by Counterpoint would run hot.
Most of the Counterpoint gear looked nice, I'll say that for it, but if someone were to walk up and give me a piece of their gear today, the first thing I'd do would be to gut it and build something else into the chassis. It's a shame, really, as there aren't that many brands I'd treat that way.
Grey |
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| stoolpigeon |
| Despite my negative remarks I like the SA7 and as a budget model I think the designer did a good job. SA7 was always a favourite of Ken Kessler, one of the few journalists I used to read. Is he still about? |
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| quinnling |
I brought a broken SA20 with a bad output stage. I'm thinking about reusing the chasiss and transformer as a donor for another hybrid. Anybody know the secondary voltage of the power transformer ? I have 16 replacement MOSFET for a Hafler XL600, I'm thinking of using a an Aikido WCF driving the Hitachi Mosfet. Any other suggestion ?
BTW, I used to have a short chasis SA7 Preamp ... I found it to be kind of hard sounding. Very simple design , and if I can remember properly the phono stage was always connected to the line stage. You can play the line source and a LP at the some time. |
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| anatech |
The simpler Counterpoint designs were always the better ones. Michael seemed to lose control and did silly things as the price tag went up. That means a small Counterpoint preamp will very probably outlast the more expensive ones. If you get a chance to see the diagram for an SA-9, you'll understand. It's a house of cards. :devilr:
Hi Grey,| quote: | | Gee...I can't imagine why anything made by Counterpoint would run hot. |
Hmmmm, could it be ..... the design! :D
Hi stoolpigeon,| quote: | | I just checked the web site and the buffer is mentioned as a prior upgrade. Charging to put it in and then charging to take it out - nice work if you can get it! |
On many models, the buffer was factory. It was required for proper operation. The DA-10 uses a discrete version of the BUF03 - messed up. The power supply is a disaster! I have one here that is dead due to an "upgrade". They yanked all the plate through parts out with the old caps. :faint: I'm trying to save it.
Hi quinnling,| quote: | | I brought a broken SA20 with a bad output stage. I'm thinking about reusing the chassis and transformer as a donor for another hybrid. Anybody know the secondary voltage of the power transformer ? |
I think the old secondary DC was 45 V bipolar. The HT should run around 330 VDC. This is what I'm working on and it's not hard to make it sound better. Dropping the idle current will cool down the transformer a lot. No more transformer failures then.
I wouldn't just gut it out of hand. You can use the same PCB unless the areas near the PCB supply fuses are burned. I made a small outboard PCB for that situation (two actually).
The original circuit is a repair job waiting to happen. Sounds bad as well.
-Chris |
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| kevinkr |
| SA-12 = Mosfet Exploding Device, I made plenty of money replacing output devices in this hybrid amp until Counterpoint went out of business and I couldn't get them anymore.. :D |
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| anatech |
Hi Kevin,
You can still get output sets from Michael. If you buy enough normal stock, you can match your own. From looking at what Michael sends, I found that I matched them tighter than the factory. It's an incredible pain in the **s to match them though. Takes a long time.
This was the major reason they failed as a company I bet. A very poor product design that should never have left the prototyping stage.
-Chris |
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| sds2000 |
Just thought I would add my two cents as I am just about finished restoring my old SA-7.1. I was never crazy about it but I figure I might add some control and "tube" sound to my Ipod d riven sencondary system.
As long as you have it open you should replace the volume and balance pots.Mine were quite scratchy. I found an exact match for tthe stock volume pot (100k) at radio shack. In mine half the electrolytics were leaking , probably due to excess heat as everything seems to look like its slightly crisped, so I replaced them all . I would look for a better way to heat sink the LM-358 regulator, I think it may be responsible for some of the heat problems.
Don't get me wrong, I seem to remember thinking it was well priced at the time I bought it and I really only have about $40 sunk into restoring it. I was also unable to find a schematic on web for my Rev 7.1 unit. |
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| anatech |
Hi sds2000,| quote: | | I was also unable to find a schematic on web for my Rev 7.1 unit. |
That's because M.E. will not release it. He wants a fortune for these poorly executed manuals too. Shame on him.
| quote: | | As long as you have it open you should replace the volume and balance pots. |
Well, they normally clean up very nicely. If you were thinking of replacing them you should have used a nicer Alps or Nobel pot.
-Chris |
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| analog_sa |
| This was drawn too many years ago. No sure why R5 has two values. The correct value is probably 4M and 1M5 is the ideal RIAA value. The grid-leak tube lowers the input impedance. |
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| poynton |
Hi.
I bought my SA-7 at a car boot sale for £50 - bargain !!
The guy had just upgraded to Krells.
The only problem I had was the switching arrangement - SW1/2 - the phono stage is always in circuit.
I sourced a 3-way ON-ON-ON from RS Components and rewired it.
I sold the SA-7 for £275 when I went CD only. (almost my bestbuy at boot sales - the complete stereo quad 22/II/FM2/AM2 for £25 will take some beating)
For those interested, I have posted the circuit here :-
http://www.yourfilelink.com/get.php?fid=364086
Andy |
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