Which of the transistors on the Type 2 board should be mounted on top of the board and which under it, connected to the heatsink?
Thank you Maros, the entire output stage including the bias sensing transistor. You are also allowed to use your own tricks😉
Hi Meanman1964,Evette,
I believe you,it's part your doing I start populating my Symef but the 1DIFFQS will be build too.I only have to order a few parts like the 39pF and 8,2pF micas.Also I need the 10ohm/3Watt resistors.
I'm very curios how the Symef will sound and behave.
Looking forward to your review of those first notes. It is rumoured that the secret is whispered during those first few moments......could it be true?
kind regards,
Harrison.
Sind Me your phone # again Mr.Harrison and I,ll tell you. Evette
Looking forward Evette will call you shortly PM me your number again 😀
Am thinking about offering both type1 and type2 PCB s in the group buy thread so kindly share your ideas on your preferred type .
I have gotten positive review for type2 PCBs. In this review there was no perceived difference in performance when compared to the type1. This is an interesting result. It provides data on the pros and cons of PCB layout. Type2 features a huge almost solid ground plane while type1 features a different type of ground plane.
Kindly share your experiences and pictures on this thread including your partial or complete builds .
kind regards,
Harrison.
I have gotten positive review for type2 PCBs. In this review there was no perceived difference in performance when compared to the type1. This is an interesting result. It provides data on the pros and cons of PCB layout. Type2 features a huge almost solid ground plane while type1 features a different type of ground plane.
Kindly share your experiences and pictures on this thread including your partial or complete builds .
kind regards,
Harrison.
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I finally drilled the holes in my heatsinks, now I only have to solder the power supply together and I have a new amplifier! 🙂
Thank you Maros,
Now we wait with bated breaths. Remember to set bias for maximum resistance before powering up then adjust bias after amp warms up and repeat again.😀
Lets know how it goes do share pics of your build. All the best.🙂
kind regards,
Harrison.
Once you post PM shipping address for your free pair of 1DIFFQC PCbs
Now we wait with bated breaths. Remember to set bias for maximum resistance before powering up then adjust bias after amp warms up and repeat again.😀
Lets know how it goes do share pics of your build. All the best.🙂
kind regards,
Harrison.
Once you post PM shipping address for your free pair of 1DIFFQC PCbs
I finally drilled the holes in my heatsinks, now I only have to solder the power supply together and I have a new amplifier! 🙂
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I got one channel working, I still have to assemble the power supply for the second channel, but I've got a little problem.
Apart from a bit of hum (due to bad grounding, haven't got a case for the amplifier yet) I can't get the amp to sing without distortion.
Fiddling around with the bias-pot doesn't really solve the problem, the signal is distorted at all bias voltages.
Maybe my supply voltage is too low?
I've got a 25V sec. transformer, so my DC voltage is around 35V.
When I measure from the +40V jack to the Ground jack I get about 18V, when I measure from the +40V to the -40V I get 35V.
Apart from a bit of hum (due to bad grounding, haven't got a case for the amplifier yet) I can't get the amp to sing without distortion.
Fiddling around with the bias-pot doesn't really solve the problem, the signal is distorted at all bias voltages.
Maybe my supply voltage is too low?
I've got a 25V sec. transformer, so my DC voltage is around 35V.
When I measure from the +40V jack to the Ground jack I get about 18V, when I measure from the +40V to the -40V I get 35V.
Hi Maros,
Thanks for the update. Almost there. Were you able to troubleshoot the problem. Do post some pictures of all sides. Did you complete the second amplifier did it display the same symptoms ?
It might be oscillation, a defective device etc etc, do you have a scope. How hot are the output devices getting. Welcome to diyaudio.
kind regards,
Harrison.
Thanks for the update. Almost there. Were you able to troubleshoot the problem. Do post some pictures of all sides. Did you complete the second amplifier did it display the same symptoms ?
It might be oscillation, a defective device etc etc, do you have a scope. How hot are the output devices getting. Welcome to diyaudio.
kind regards,
Harrison.
I got one channel working, I still have to assemble the power supply for the second channel, but I've got a little problem.
Apart from a bit of hum (due to bad grounding, haven't got a case for the amplifier yet) I can't get the amp to sing without distortion.
Fiddling around with the bias-pot doesn't really solve the problem, the signal is distorted at all bias voltages.
Maybe my supply voltage is too low?
I've got a 25V sec. transformer, so my DC voltage is around 35V.
When I measure from the +40V jack to the Ground jack I get about 18V, when I measure from the +40V to the -40V I get 35V.
The schematic is an idea, its a dream. Then there are those that turn dreams into tangible reality.
The PCB is etched. One by one the components are added. As the components are added a relationship starts to form between builder and subject.
Then the fateful day comes when the amplifier is complete and is plugged in and the first notes come out.......do tell us San and thanks for sharing and advancing the state of the art. All the best,😀🙂😎
Harrison.
The PCB is etched. One by one the components are added. As the components are added a relationship starts to form between builder and subject.
Then the fateful day comes when the amplifier is complete and is plugged in and the first notes come out.......do tell us San and thanks for sharing and advancing the state of the art. All the best,😀🙂😎

Harrison.
Attachments
The schematic is an idea, its a dream. Then there are those that turn dreams into tangible reality.
The PCB is etched. One by one the components are added. As the components are added a relationship starts to form between builder and subject.
Then the fateful day comes when the amplifier is complete and is plugged in and the first notes come out.......do tell us San and thanks for sharing and advancing the state of the art. All the best,😀🙂😎
Harrison.
Hi all,
Hi Mr. Harrison
I'm newcomer in here,
A lot of great designers in this world that will make us confused. Finally I decided to assemble this amp.
Thank you Sir for the support.
Only with a potluck part, the SYMEF is really different. Yes....this amp is unbeliveble.
Very easy adapted according to our tastes.
Very convenient be heard (of all kinds of music),
The bass is more than power full,
Verry clear articulations,
the hight is very crisp and smooth.
With the MP3 format (196kbps) even no less with the FLAC.
Maybe you won't believe it, but this is the reality.
Sorry for my bad english
Thank you Sir, you make my life happier
Kind regards
San
Thank you for joining us San. You do have one very rare amplifier there.
Thanks for the feedback 😎 . You have contributed to the wealth of knowledge that is amplifier engineering.
kind regards,
Harrison.
Thanks for the feedback 😎 . You have contributed to the wealth of knowledge that is amplifier engineering.
kind regards,
Harrison.
Hi all,
Hi Mr. Harrison
I'm newcomer in here,
A lot of great designers in this world that will make us confused. Finally I decided to assemble this amp.
Thank you Sir for the support.
Only with a potluck part, the SYMEF is really different. Yes....this amp is unbeliveble.
Very easy adapted according to our tastes.
Very convenient be heard (of all kinds of music),
The bass is more than power full,
Verry clear articulations,
the hight is very crisp and smooth.
With the MP3 format (196kbps) even no less with the FLAC.
Maybe you won't believe it, but this is the reality.
Sorry for my bad english
Thank you Sir, you make my life happier
Kind regards
San
Still waiting for more new exciting reviews 😀. Its really quiet 🙁.
Kindly give your feedback on especially the type2. Post pictures of your partial builds etc.
This could be very well be the amplifier most were waiting for. What do your ears think ?
kind regards,
Harrison.
Kindly give your feedback on especially the type2. Post pictures of your partial builds etc.
This could be very well be the amplifier most were waiting for. What do your ears think ?
kind regards,
Harrison.
In a moving process. All diy is on hold for the time being 🙂
Will do a comeback around christmas I guess 😉
Still I am playing og the Symef (modell 1) every day when I am at home.. A purely awesome amp.
Will do a comeback around christmas I guess 😉
Still I am playing og the Symef (modell 1) every day when I am at home.. A purely awesome amp.
Still waiting for more new exciting reviews 😀. Its really quiet 🙁.
Kindly give your feedback on especially the type2. Post pictures of your partial builds etc.
This could be very well be the amplifier most were waiting for. What do your ears think ?
kind regards,
Harrison.
It looks like LazyCat "formula" was much better.
It looks like LazyCat "formula" was much better.
How do you know? Did build both of them and compare? Or Just did analysis of the circuits? What is the basis?
Hope you enjoy your move 😉 . Am cooking up the next hat trick 😉
In a moving process. All diy is on hold for the time being 🙂
Will do a comeback around christmas I guess 😉
Still I am playing og the Symef (modell 1) every day when I am at home.. A purely awesome amp.
It looks like LazyCat "formula" was much better.
Hi Dadod, as Routhun points out its still an open problem

How do you know? Did build both of them and compare? Or Just did analysis of the circuits? What is the basis?
Hi Routhun,
Good to hear from you, hows the progress 😀
kind regards,
Harrison.
Hi Dadod, as Routhun points out its still an open problem
kind regards,
Harrison.
LazyCat commercialized his amp and you did not yet.
regards Damir
Hi Damir,
It is sometimes difficult to commercialize some things, say industry standards. The group of amplifiers currently published and made available to the public by Harrison Audio Labs (HAL) are in a word an industry standard. This standard will hold for the next couple of hundred years as a reference.
If say TCP/IP were to be commercialized, those same techniques would come in handy.
Every audio company and sound studio in the world right now knows that there is no beating those amplifiers.
The claims above are rather strong😀 as a result they need to be proved by user feedback into statements of fact 😉.
kind regards,
Harrison.
It is sometimes difficult to commercialize some things, say industry standards. The group of amplifiers currently published and made available to the public by Harrison Audio Labs (HAL) are in a word an industry standard. This standard will hold for the next couple of hundred years as a reference.
If say TCP/IP were to be commercialized, those same techniques would come in handy.
Every audio company and sound studio in the world right now knows that there is no beating those amplifiers.
The claims above are rather strong😀 as a result they need to be proved by user feedback into statements of fact 😉.
kind regards,
Harrison.
LazyCat commercialized his amp and you did not yet.
regards Damir
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