Hello Sy! I wanna modify it, because its more than 20 years old. I know that Micheal Elliot does the same, but that will cost me to much and I like upgrading vintage audio. Caps are drying out and the circuits can be improved by putting newer/better material in it. Michael Elliot himself says the toriodals will be better. Thanks for the answer, Teake.
Well, he DOES want to sell you mods, whether you need them or not.
Toroids are very efficient at coupling line noise into the circuit. So a good modder will also add common-mode filtering to end up with an expensive replacement for a cheap E-I transformer at a higher parts count with only a small performance degradation. Seriously: don't do it. You'll do better by merely adding a separate transformer (E-I or R-core) for the heaters; it will take some load off the main transformer and keep the HV diodes' switching spikes from coupling noise back through the heaters. And it's a cheap and easy mod.
Replacing the electrolytics is pretty straightforward. I'd avoid the exotic types and stick to major manufacturers available through places like Allied, Mouser, or Digikey.
Toroids are very efficient at coupling line noise into the circuit. So a good modder will also add common-mode filtering to end up with an expensive replacement for a cheap E-I transformer at a higher parts count with only a small performance degradation. Seriously: don't do it. You'll do better by merely adding a separate transformer (E-I or R-core) for the heaters; it will take some load off the main transformer and keep the HV diodes' switching spikes from coupling noise back through the heaters. And it's a cheap and easy mod.
Replacing the electrolytics is pretty straightforward. I'd avoid the exotic types and stick to major manufacturers available through places like Allied, Mouser, or Digikey.
Hello Sy! I wanna modify it, because its more than 20 years old. I know that Micheal Elliot does the same, but that will cost me to much and I like upgrading vintage audio. Caps are drying out and the circuits can be improved by putting newer/better material in it. Michael Elliot himself says the toriodals will be better. Thanks for the answer, Teake.
Ouch! I've been pinged!!!
Hi Teake,
Wow. You do not have a good reason to do what you are planning to do. Just because it's there, it needs changing???
No.
I am extremely familiar with these (and other) Counterpoint products as I did warranty service on them. I have spent the years since Counterpoint went out of business by correcting the design errors to make these more reliable. More often than not, they sound better as a side benefit.
Teake, it sounds like you are reading too much without a good understanding of the reality of circuit design. No fault of yours and I am not putting you down for this. It does make you an easy mark for the people who do unnecessary work, and worse - the hackers. Electronics and the sub class of audio are simply a small part of the study of physics. All those laws apply. There are some unknowns and some people exploit that in ways I can't agree with. Others learn the subtleties to create better sounding equipment. To do this, you must understand both the subject matter and parts.
In closing, my advice to you is simple. As long as you can solder neatly, without damaging anything, replace some of the capacitors. Do not install larger values! Buy new tubes. I recommend Electroharmonix. Big bang for the buck and their 6922EH does solve some Counterpoint issues.
Then,as you listen to some music, learn about electronics. Avoid "white papers" like the plague. Most are about 10% truth and the rest is marketing hype. Since you like to restore older equipment, buy and read books of the era. Another excellent source of information is "Valve Amplifiers" by Morgan Jones. This is a new look at audio electronics. Tubes in particular. Get it. Read it. Available from Amazon (and yes, I have both Morgan's excellent books). Another would be RDH4. That should keep you busy for a bit. After reading those, your knowledge will exceed that of most "modders". Knowledge will also save you a ton of money. Far more than the books will cost.
-Chris
Hi Teake,
Wow. You do not have a good reason to do what you are planning to do. Just because it's there, it needs changing???
No.
Huh? Many old designs are very solid. There is no upgrade or change that will make things better (believe it or not!). All you can do is replace the tired parts with good quality ones of the same. SY made this very clear. I know, it lacks the romance of changing things. Newer designs are more likely to be faulty. Having said that, the 3.1 is done "more right" than most of M.E.'s later productions. His newer preamps are said to be a return to this basic design. I have not investigated that. I honestly do not see the need until I get one in front of me.
I have to agree more than 100 % with SY on this. Sad but true.
I am extremely familiar with these (and other) Counterpoint products as I did warranty service on them. I have spent the years since Counterpoint went out of business by correcting the design errors to make these more reliable. More often than not, they sound better as a side benefit.
Bad idea - for all the correct reasons SY stated. He's right you know, Toroid transformers are only a good choice if your mounting height is limited. Yours is not. Also, the mods M.E. is doing to that transformer are not right. They run too hot as the part is under sized. If I were to redesign that power supply, I would probably install an EI core that was a bit larger to reduce the operating temperature. I'd go with a Hammond product. Something stock and close if possible. There is zero reason to do this unless yours burns out.
Well, he is wrong. What makes his mod better is that he can make more money off the same product for years to come. Now the part I don't like about this. You are taking the information he is giving and doing it yourself without knowing enough. Do you know how M.E. mounts that new transformer? It rolls around loose inside. I've seen a couple.
Teake, it sounds like you are reading too much without a good understanding of the reality of circuit design. No fault of yours and I am not putting you down for this. It does make you an easy mark for the people who do unnecessary work, and worse - the hackers. Electronics and the sub class of audio are simply a small part of the study of physics. All those laws apply. There are some unknowns and some people exploit that in ways I can't agree with. Others learn the subtleties to create better sounding equipment. To do this, you must understand both the subject matter and parts.
In closing, my advice to you is simple. As long as you can solder neatly, without damaging anything, replace some of the capacitors. Do not install larger values! Buy new tubes. I recommend Electroharmonix. Big bang for the buck and their 6922EH does solve some Counterpoint issues.
Then,as you listen to some music, learn about electronics. Avoid "white papers" like the plague. Most are about 10% truth and the rest is marketing hype. Since you like to restore older equipment, buy and read books of the era. Another excellent source of information is "Valve Amplifiers" by Morgan Jones. This is a new look at audio electronics. Tubes in particular. Get it. Read it. Available from Amazon (and yes, I have both Morgan's excellent books). Another would be RDH4. That should keep you busy for a bit. After reading those, your knowledge will exceed that of most "modders". Knowledge will also save you a ton of money. Far more than the books will cost.
-Chris
Hi Teake,
We are all learning, every day as we go through life. I do admire those who are willing to actually sit down and do something.
Take my words as helpful advice. I do want you to enjoy the hobby, but I also want to keep you from doing something you will regret later once you know more. You should ask for opinions and help when you think it would be helpful. I figure it's up to experienced people to help out the less experienced.
I do have an idea for you. Something that will really help you get used to electronics and audio in general. It doesn't matter whether you work with tubes, solid state or both. I am in that latter camp. Get some equipment together and set up a workbench where you can experiment, and also do some projects. Then, take some basic circuits. These can be low powered audio units (tube or transistor), or a circuit you build up from scratch. Kits are fine. I think that the SymAsym would be a pretty good place to start. The important thing is sound quality rather than power output. You could run the SymAsym from 30 volt rails and experiment with different concepts. You will need a sine wave signal source and harmonic distortion analyzer (HP product is not expensive and works very well for these). You will need a dual trace 'scope, 20 MHz is fine. A half decent sound card / computer with some programs to run it with is a good addition. Notice that you need other instruments, not just a sound card. You will understand why once you start to use the equipment.
The only problem with this is that is can be frustrating and addictive at the same time. A very satisfying hobby where you can learn your entire life.
-Chris
We are all learning, every day as we go through life. I do admire those who are willing to actually sit down and do something.
Take my words as helpful advice. I do want you to enjoy the hobby, but I also want to keep you from doing something you will regret later once you know more. You should ask for opinions and help when you think it would be helpful. I figure it's up to experienced people to help out the less experienced.
I do have an idea for you. Something that will really help you get used to electronics and audio in general. It doesn't matter whether you work with tubes, solid state or both. I am in that latter camp. Get some equipment together and set up a workbench where you can experiment, and also do some projects. Then, take some basic circuits. These can be low powered audio units (tube or transistor), or a circuit you build up from scratch. Kits are fine. I think that the SymAsym would be a pretty good place to start. The important thing is sound quality rather than power output. You could run the SymAsym from 30 volt rails and experiment with different concepts. You will need a sine wave signal source and harmonic distortion analyzer (HP product is not expensive and works very well for these). You will need a dual trace 'scope, 20 MHz is fine. A half decent sound card / computer with some programs to run it with is a good addition. Notice that you need other instruments, not just a sound card. You will understand why once you start to use the equipment.
The only problem with this is that is can be frustrating and addictive at the same time. A very satisfying hobby where you can learn your entire life.
-Chris
Hi Teake ,
I have a good experience with Counterpoint , since I’ve
repaired , restored and up-graded many of them ,
including the “ almost-never-seen “ SA-11 tube preamp ,
the SA-4 tube OTL amp and the NPM ( Natural Progression
Mono ) ( amazing sound !! ) ... , and others .
I agree with EVERY word that Chris and SY have said .
The only “ tip ” I want to give is :
Most of Counterpoint’s products , run VERY hot , and this
tends to degrade all sensible parts , mainly electrolitic
caps ( the victims ) , ceramic caps , trim-pots , etc.
Replace them and enjoy the sound ,
Good luck ,
Carlos
I have a good experience with Counterpoint , since I’ve
repaired , restored and up-graded many of them ,
including the “ almost-never-seen “ SA-11 tube preamp ,
the SA-4 tube OTL amp and the NPM ( Natural Progression
Mono ) ( amazing sound !! ) ... , and others .
I agree with EVERY word that Chris and SY have said .
The only “ tip ” I want to give is :
Most of Counterpoint’s products , run VERY hot , and this
tends to degrade all sensible parts , mainly electrolitic
caps ( the victims ) , ceramic caps , trim-pots , etc.
Replace them and enjoy the sound ,
Good luck ,
Carlos
Hi miligor,
Since Elliot sells manuals, and I have an agreement that states the information is not to be transmitted, I can't send you the schematic. Besides, the manuals aren't very good and information is lightly sprinkled across many pages. Scanner is busted as well.
However, all is not lost. There are copies of this information out there on the 'web. You just have to search a little bit. I can tell you that this preamp used 6DJ8 tubes, later changed to 6922 types. That's an industrial version that uses a "frame grid" that helps reduce microphonics and also makes these types more consistent from tube to tube. That's a bonus. There may have been an earlier version that used 12AY7 (?) tubes for the phono stage. If you check Michael Elliot's new web site, he does list the tube compliments each release used.
Are you repairing one, or are you intending to build a copy?
-Chris
Since Elliot sells manuals, and I have an agreement that states the information is not to be transmitted, I can't send you the schematic. Besides, the manuals aren't very good and information is lightly sprinkled across many pages. Scanner is busted as well.
However, all is not lost. There are copies of this information out there on the 'web. You just have to search a little bit. I can tell you that this preamp used 6DJ8 tubes, later changed to 6922 types. That's an industrial version that uses a "frame grid" that helps reduce microphonics and also makes these types more consistent from tube to tube. That's a bonus. There may have been an earlier version that used 12AY7 (?) tubes for the phono stage. If you check Michael Elliot's new web site, he does list the tube compliments each release used.
Are you repairing one, or are you intending to build a copy?
-Chris
Hi Carlos,
A clone would be easily done. It's not like these are complicated in design or anything. Along the way, power supply issues can eliminated by designing a better supply. Same thing for underrated capacitors, design in the proper values and include room for them.
From my point of view, these sounded pretty good and were also quiet. The design is old now, and since the designers originally made enough errors (and the company died too), I can't see any problems in doing this.
Look at it this way. People can end up with a preamp that sounds at least as good, with far better documentation (not hard) and gain an understanding of the design. I'm not about to embark on a project like this, but I think someone should at some point. The reason? Older ones I restore still convert people over to this brand. They sound pretty good. Perfect? No. But far better than the average tube preamp. The copy will introduce a better circuit design in the power supply and hopefully get away from the fact that he runs the heaters all the time (except for the rectifier tube). So there are definite improvements to be made with this basic design. Maybe even add an MC stage using J-Fets or really quiet tubes.
-Chris
A clone would be easily done. It's not like these are complicated in design or anything. Along the way, power supply issues can eliminated by designing a better supply. Same thing for underrated capacitors, design in the proper values and include room for them.
From my point of view, these sounded pretty good and were also quiet. The design is old now, and since the designers originally made enough errors (and the company died too), I can't see any problems in doing this.
Look at it this way. People can end up with a preamp that sounds at least as good, with far better documentation (not hard) and gain an understanding of the design. I'm not about to embark on a project like this, but I think someone should at some point. The reason? Older ones I restore still convert people over to this brand. They sound pretty good. Perfect? No. But far better than the average tube preamp. The copy will introduce a better circuit design in the power supply and hopefully get away from the fact that he runs the heaters all the time (except for the rectifier tube). So there are definite improvements to be made with this basic design. Maybe even add an MC stage using J-Fets or really quiet tubes.
-Chris
Hi Chris ,
You are correct with some models from Counterpoint , BUT when
I wrote the previous post , I were thinking about specific models
from Michael Elliot .
I have a good client that loves the top-models of Counterpoint ,
AND knows Michael Elliot personally ,thus I had the oportunity
to make repairs ans up-grades in the following models :
SA – 11 – A preamplifier with 15 tubes , only two of them dedicated
to the sound amplification , the rest is dedicated to the power
supply , I can not do better , and I guess that you neither .
This preamplifier is supposedly the guilty for the Counterpoint bank-
ruptcy , and when was featured , had the same cost of a Cadillac ,
and only about 50 of them were built . The sound is amazing ( and
the weight and the generated heat ,too )
SA – 4 – This is a OTL power amplifier , that uses TV sweep tubes ,
very hard to find and very expensive , the driver stage and servo bias
stage is infinitely complicated , to say the least , the power supply is
not an exception . I do not like this one .
NPM or Natural Progression Mono – A Hybrid power amplifier with
one of the best sound I ever heard ( perhaps , the best ... ) , it
uses 6DJ8 on the front end and Toshiba IGBT’s in the final stage ,
with a very , very well done power supply , and a sound that touches
your heart and your soul .
Do not forget , that Michael had two different lines , a "top" high-end
line and a “ cheaper “ or more “ popular “ line ,the later was necessary
to improve the sales and “ make money “ .
If you are sayng , that you can clone and even improve the circuit and
performance of the so said “ popular line , I agree entirely with you .
BUT about the top high-end line , things are very much different .
By the way , when I did need the above models’s Service Manuals , I
had to buy them direct from Michael Elliot ( He is the only , that has ,
obviously you know that ) and he made me “swear” that I were
not planing to build clones in Brazil ( crazy man ... ) that is the reason
why I said on my previous post “ Michael will die .... “
Sorry about my long reply , I think things are clear now
Best Regards,
Carlos
Hi Carlos,
Your client's relationship with Michael has no effect on the design or intentions behind the design for any of Michael's products at all. I am not really sure how much engineering Michael did at this point in time, but let's accept his advertising and agree that he designed everything (although the SA-4 is doubtful, and anything before that is extremely doubtful). However, this relationship may have got you a reduced price on the manuals (that you are not allowed to divulge in the open). It's all good, and I hope he gave you a massive break!
The SA-4. Now there is a product that should never have existed! He should have learned from the Futterman's history, although Moscode seems to be alive and well. It's telling that these amplifiers had good protection circuits whereas Counterpoint really only had one attempt at that. That was the analog computer in the SA-220 that was supposed to prevent the outputs from being over driven. They all came from the factory with this circuit set to it's least sensitive (ineffective) settings.
He had one newer amplifier (solid state) that had, instead of a bias control, a heat sink temperature control. I kid you not! It would draw about 2A on turn on (@120 VAC) which would drop down as the heat sinks warmed up. He went to all the trouble of using a reference IC and compared this to the voltage drop of a diode to establish the temperature. The "bias" adjustment was actually comparing a fraction of the reference value to the diode voltage drop. A ton of work to carefully design a heat sink heater, but not anything that would keep the bias current in any range. Stunning.
Michael isn't a bad guy from where I sit, but I have a huge problem with how much he charges for service information and work. His updates frequently reduce the performance of the equipment and he continues to extract a living from those poor souls who bought into this product. The product is sometimes difficult to access in order to repair it. Poorly designed for future service. The actual alignment of the circuits is also a time consuming task as well.
I'll clarify my comments a little then. Building a clone (not a copy) of his designs would be extremely easy to do. As far as support circuitry is concerned, it would be easier to deliver the same or better power quality would make this job easier, and the resulting equipment would be more reliable. It would probably have a lower noise floor as well. The SA-9 and SA-11 (or upscale variants) would end up physically smaller, lighter and through off a small fraction of the heat they emit right now. There is no excuse for those designs at all.
I'm actually pretty familiar with Michael's product line (newer more) and "upgrades" than you know. Probably shouldn't argue too much down that road.
Note:"Tube rolling" is not possible with most of this equipment due to the requirement of adjusting the circuit for each tube that you install. To swap tubes around without doing the adjustments completely invalidates what you are trying to do.
The crazy person would be the one who actually did try to create exact copies of his equipment. That would certainly be ill-advised!
My earlier comments stand. It would be very easy to create a clone of this product line while avoiding most of the mistakes by redesigning the power supplies. I will modify this statement when talking about the Counterpoint amplifiers. Those have serious errors in design throughout, so a complete re-engineer would leave you with the product idea and rough classification (like tube voltage amp and solid state current stage). The DA-10 is similarly crippled. The buffer and power supplies should be cut out and replaced wholesale. That happens to be one of my projects for an unhappy Counterpoint owner that had this unit "upgraded". It died on the table, but no-one knew it. It was charged to the customer and returned. No excuses for that.
Carlos, I'm not unhappy with anything you've said so far. I will warn people about the downsides to this brand. However, the preamps sound great when they are running.
-Chris
No offense intended here.
Your client's relationship with Michael has no effect on the design or intentions behind the design for any of Michael's products at all. I am not really sure how much engineering Michael did at this point in time, but let's accept his advertising and agree that he designed everything (although the SA-4 is doubtful, and anything before that is extremely doubtful). However, this relationship may have got you a reduced price on the manuals (that you are not allowed to divulge in the open). It's all good, and I hope he gave you a massive break!
The SA-4. Now there is a product that should never have existed! He should have learned from the Futterman's history, although Moscode seems to be alive and well. It's telling that these amplifiers had good protection circuits whereas Counterpoint really only had one attempt at that. That was the analog computer in the SA-220 that was supposed to prevent the outputs from being over driven. They all came from the factory with this circuit set to it's least sensitive (ineffective) settings.
The SA-11 would be far easier to clone as there are only a few tubes that actually deal with audio in there as you noted. Was it two per channel, or two total? I can't remember off-hand. That model has been so badly designed that it can't really be modified in any meaningful way with an eye to eliminating it's problems. After working on these, I decided the only way to "fix" one would be to do a complete redesign from the ground floor. The shunt regulators used for heater regulation were poorly thought out and executed for one. The massive power supply is a complete and total waste of materials, and a huge liability where reliability is concerned. The SA-9 and it's "improved" offspring traveled even further along the silly path, using a pair of heavy power supply units that were highly likely to arc one or both Cetron rectifiers in each. All this was for the purpose of supplying 6-6922 tubes (I think) with B+ and heater power! Get real! I'd have to go back to the manual for each model to be 100% sure, but the truth will be extremely close to what I have posted here.
He had one newer amplifier (solid state) that had, instead of a bias control, a heat sink temperature control. I kid you not! It would draw about 2A on turn on (@120 VAC) which would drop down as the heat sinks warmed up. He went to all the trouble of using a reference IC and compared this to the voltage drop of a diode to establish the temperature. The "bias" adjustment was actually comparing a fraction of the reference value to the diode voltage drop. A ton of work to carefully design a heat sink heater, but not anything that would keep the bias current in any range. Stunning.
Michael isn't a bad guy from where I sit, but I have a huge problem with how much he charges for service information and work. His updates frequently reduce the performance of the equipment and he continues to extract a living from those poor souls who bought into this product. The product is sometimes difficult to access in order to repair it. Poorly designed for future service. The actual alignment of the circuits is also a time consuming task as well.
I'll clarify my comments a little then. Building a clone (not a copy) of his designs would be extremely easy to do. As far as support circuitry is concerned, it would be easier to deliver the same or better power quality would make this job easier, and the resulting equipment would be more reliable. It would probably have a lower noise floor as well. The SA-9 and SA-11 (or upscale variants) would end up physically smaller, lighter and through off a small fraction of the heat they emit right now. There is no excuse for those designs at all.
I'm actually pretty familiar with Michael's product line (newer more) and "upgrades" than you know. Probably shouldn't argue too much down that road.
Note:"Tube rolling" is not possible with most of this equipment due to the requirement of adjusting the circuit for each tube that you install. To swap tubes around without doing the adjustments completely invalidates what you are trying to do.
An unhappy combination to be sure. There is a very good reason why IGBTs are not used by the bulk of the audio community. They are ill suited to the job.
Absolutely, it would be much easier. His earlier, more simple models were designed far better.
Not crazy, paranoid.
The crazy person would be the one who actually did try to create exact copies of his equipment. That would certainly be ill-advised!
My earlier comments stand. It would be very easy to create a clone of this product line while avoiding most of the mistakes by redesigning the power supplies. I will modify this statement when talking about the Counterpoint amplifiers. Those have serious errors in design throughout, so a complete re-engineer would leave you with the product idea and rough classification (like tube voltage amp and solid state current stage). The DA-10 is similarly crippled. The buffer and power supplies should be cut out and replaced wholesale. That happens to be one of my projects for an unhappy Counterpoint owner that had this unit "upgraded". It died on the table, but no-one knew it. It was charged to the customer and returned. No excuses for that.
Carlos, I'm not unhappy with anything you've said so far. I will warn people about the downsides to this brand. However, the preamps sound great when they are running.
-Chris
Hi Chris ,
Just to be direct and summarize all of our posts :
As you , I do not like the Counterpoint products .
I think that we agree about that . No doubts .
__ About SA-4 I agree entirely
__ About SA-11 ,actually only two tubes ( 6SN7 ) for the audio
portion ( one per channel ) , and another two tubes( 6SN7 )
( one per channel ) for a complementary and a doubtful use
called by him : “ phase inverter “.
About my client’s friendship with Michael , I only
did the mention, to explain that even with friends ,
he acts in a paranoid way .
The only point that we disagree , is about the
Power Amplifier NPM ( Natural Progression Mono )
If you have the oportunity , please listen to it .
Forget about technical considerations , if the 6DJ8
matches or do not matches with IGBT’s , if IGBT’s
are or not suitable for hi-fi circuits .
Do it , like I did , let our engineer way of thinking
and our technical considerations , behind .
Just listen and enjoy the set , I am sure that you will
be amazed with the sound quality .
Regards ,
Carlos
Just to be direct and summarize all of our posts :
As you , I do not like the Counterpoint products .
I think that we agree about that . No doubts .
__ About SA-4 I agree entirely
__ About SA-11 ,actually only two tubes ( 6SN7 ) for the audio
portion ( one per channel ) , and another two tubes( 6SN7 )
( one per channel ) for a complementary and a doubtful use
called by him : “ phase inverter “.
About my client’s friendship with Michael , I only
did the mention, to explain that even with friends ,
he acts in a paranoid way .
The only point that we disagree , is about the
Power Amplifier NPM ( Natural Progression Mono )
If you have the oportunity , please listen to it .
Forget about technical considerations , if the 6DJ8
matches or do not matches with IGBT’s , if IGBT’s
are or not suitable for hi-fi circuits .
Do it , like I did , let our engineer way of thinking
and our technical considerations , behind .
Just listen and enjoy the set , I am sure that you will
be amazed with the sound quality .
Regards ,
Carlos
Hi Carlos,
Are you still active here in SP? My name is Lee and I am an expat living in Vila Mariana half of the year. I am not an engineer but have been involved in high-end audio since Bozak was all the rage!
lhimelfarb@hotmail.com.
Tchau for now!
Are you still active here in SP? My name is Lee and I am an expat living in Vila Mariana half of the year. I am not an engineer but have been involved in high-end audio since Bozak was all the rage!
lhimelfarb@hotmail.com.
Tchau for now!
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