Hello -
I'm not sure why you're asking me instead of Erno Borbely. This circuit is not the kind of thing that I'd recommend. However, I can make a couple of comments:
1) The power supply rejection ratio of this circuit isn't very good, so its performance will be quite dependent on the quality of the power supply.
2) It is possible to blow the 2SJ74s used in the output stage. These are rated at 25 volts and if the circuit is running up to the clipping point, the full rail of 36 volts will be applied. You might try reducing the supply rails.
Hope this helps,
Charles Hansen
I'm not sure why you're asking me instead of Erno Borbely. This circuit is not the kind of thing that I'd recommend. However, I can make a couple of comments:
1) The power supply rejection ratio of this circuit isn't very good, so its performance will be quite dependent on the quality of the power supply.
2) It is possible to blow the 2SJ74s used in the output stage. These are rated at 25 volts and if the circuit is running up to the clipping point, the full rail of 36 volts will be applied. You might try reducing the supply rails.
Hope this helps,
Charles Hansen
Charles Hansen, help please!
Hi, Charles Hansen,
Why do you say this in Etalon thread
1. Error correction can improve damping factor. Is applying error correction gives AUDIBLE difference/result (not only measurement result?)
2. I want to use error correction, but also parrareled (4 pairs) or triple emitor darlington output. Is this makes the error correction not worth it ( you compared error correction with parrareled output)
3. Please explain why you dont suggest error correction.
Hi, Charles Hansen,
Why do you say this in Etalon thread
I'm very interested with error correction, but your indications are not to use them. Including the comment by AndyC. I have questions.
1. Error correction can improve damping factor. Is applying error correction gives AUDIBLE difference/result (not only measurement result?)
2. I want to use error correction, but also parrareled (4 pairs) or triple emitor darlington output. Is this makes the error correction not worth it ( you compared error correction with parrareled output)
3. Please explain why you dont suggest error correction.
Can anyone help, where can I see Halcro design or at least Halcro patent? Some said Halcro uses modified error correction, I wanted to see what it likes.
Hello, Charles Hansen. I thought I have made some mistakes in my words. I mean to find an excellent power supply circuit that is used in Erno_Borbely's EB-2000/402 SE Balanced Jeft Lineamp. Can you give me some recommends(advice)? Thanks very much!
Oooooo
Hello, Charles Hansen. I thought I have made some mistakes in my words. I mean to find an excellent power supply circuit that is used in Erno_Borbely's EB-2000/402 SE Balanced Jeft Lineamp. Can you give me some recommends(advice)? Thanks very much!
Hello, Charles Hansen. I thought I have made some mistakes in my words. I mean to find an excellent power supply circuit that is used in Erno_Borbely's EB-2000/402 SE Balanced Jeft Lineamp. Can you give me some recommends(advice)? Thanks very much!
I built a nearly exact example of this design for the Grateful Dead at Alembic Inc in 1973. It is somewhat dated, but Walt Jung's power supplies should work OK. Be careful about power supply noise, as it can easily get into the design.
lumanauw said:
Go to:
http://patft.uspto.gov/netahtml/srchnum.htm
and search under patents 6600367 and 5892398
Re: Charles Hansen, help please!
Error correction is negative feedback with extra gain in the feedback loop itself. In my experience, a zero feedback design sounds better than a design with feedback.
lumanauw said:
Error correction is negative feedback with extra gain in the feedback loop itself. In my experience, a zero feedback design sounds better than a design with feedback.
... sound better...
Sometimes I was asking by mail Bruce Candy, why he don't write on this forum. His answer was short ( approximately ) : " Persuaded is product, not blables ". Although I don't hear his amp, I belive in quality of his product, 'cos I'm many years using in my amps the same Hawksford's circuit.
Sometimes I was asking by mail Bruce Candy, why he don't write on this forum. His answer was short ( approximately ) : " Persuaded is product, not blables ". Although I don't hear his amp, I belive in quality of his product, 'cos I'm many years using in my amps the same Hawksford's circuit.
Hi Lumanaw
Hiii..
You asked for the Halcro patent as you said before, I get the patent in my hand right now, but it just an usual design, nothing new...but if you interested you may contact me..
Cheerss,
Lukio
Hiii..
You asked for the Halcro patent as you said before, I get the patent in my hand right now, but it just an usual design, nothing new...but if you interested you may contact me..
Cheerss,
Lukio
Re: Oooooo
Since the audio circuit is zero feedback, I would also recommend using a zero feedback power supply regulator. For an example, read the thread:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=33191&highlight=
Especially read posts #53 and #54. You will have a nice sounding regulator that way. Good luck!
Wizard said:
Since the audio circuit is zero feedback, I would also recommend using a zero feedback power supply regulator. For an example, read the thread:
http://www.diyaudio.com/forums/showthread.php?s=&threadid=33191&highlight=
Especially read posts #53 and #54. You will have a nice sounding regulator that way. Good luck!
OK, can you describe whats the audible difference between audio amplifier using error correction and normal output stage (like triple darlington emitor output)? Which is better sounding?
Charles,
Thanks for the explenation. It seems that we are talking in a different situation. While I wanted to compare error correction still in feedback world (with parrareled outputs), you talked comparing feedback world with non-feedback world.
If you are still in feedback world, which do you prefer? Error correction or parrareled output?
Since you are in non-feedback world, I have a question that I have wondered for a long time. If I built audio power amp with Open loop gain 30X (by adjusting RC-RE for each transistor), but I put feedback so that closed loop mathematically tobe 100X, what happens? Will the amp still works in 30X gain, but it can hold DC offset like ordinary feedback amp? Will this considered tobe non-feedback amp, because closed loop is larger than open loop gain?
Thanks for the explenation. It seems that we are talking in a different situation. While I wanted to compare error correction still in feedback world (with parrareled outputs), you talked comparing feedback world with non-feedback world.
If you are still in feedback world, which do you prefer? Error correction or parrareled output?
Since you are in non-feedback world, I have a question that I have wondered for a long time. If I built audio power amp with Open loop gain 30X (by adjusting RC-RE for each transistor), but I put feedback so that closed loop mathematically tobe 100X, what happens? Will the amp still works in 30X gain, but it can hold DC offset like ordinary feedback amp? Will this considered tobe non-feedback amp, because closed loop is larger than open loop gain?
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