Gentlemen please, do not let something like this keep us from benefitting from your combined knowledge.
As my understanding of electronics is somehow limited, I feel compelled to post questions in order to be sure I can build based on existing ideas. As an old math's teacher I got used to be questioned and I always filter out the possible "personal strikes" because I know it is all part of the learning process.
This process might be fatiguing for others and even misleading but let us keep our cool stance naturally endemic to this forum.
I accept your apologies. And I am sorry to overreact . Please keep correcting my errors, but also remember that making mistakes is human .
Hope you get the sleep right , as it is an important thing. I also have minor anxiety problems , and sometimes is also hard to get proper sleep.
Ricardo, keep making those questions
I am sorry if my last answer was wrong , I'm most confesse that I am at this moment more focus in the voltage regulators.
And Kean is the right person to answer those questions about his buffer.
I have the buffer working in my system. I measured square wave first without the low pass filter at the input but with the compensation. It certainly helps but the input filter is needed too.
How does it sound ? Very good and i hear differences to the Piglets Dad i used before.
I would say the Kean Buffer is even less " there ", so more transparent.
I hear a small problem with focus but one channel has the Fet and the other not.
I will rebuild and then listen more.
How does it sound ? Very good and i hear differences to the Piglets Dad i used before.
I would say the Kean Buffer is even less " there ", so more transparent.
I hear a small problem with focus but one channel has the Fet and the other not.
I will rebuild and then listen more.
Attachments
I can't figure out what that is. I did a search and this page of this thread was the third result.
Mine mine mine.... No the Tube-amps are LA-audio made by Lennart Andersen from Denmark.. They are from the 90'ies. the toroids are cored and air-gapped silicon strip with double shields they have a power band-with of more than 60 KHz (if I remember it right). The amps sound really good detailed and fast. I used to own a pair of the larger sisters with two pair output tubes, but I lost them to an uninvited visitor the apparently felt he needed them and the preamp RiAA more than I did.
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This is a fast VU meter. I check channel balance with it. I bought it because i had always to make the right channel ca.1.5 dB louder to center the image so i thought it was my cartridge or another problem. That did not prove to be the case. The VU meter shows higher peaks in the right channel then in the left. I have to place my speakers slightly asymmetric so it may be a room acoustic effect. Anyway.
The CD player is a Forsell Air reference. The top unit is the drive. It floats the CD on air and it is put in " upside down ". The other golden-black unit under it is the DA converter.
This is a huge machine but i did not find anything better until now.
With high resolution material on Amarra it sounds even better but as a CD player the Forsell is still the machine to beat.
The amps are LA Audio 6550 push-pull Class A.
They are rather old, from the early 90th but heavy modified. Better caps, new wiring that improved S/N and so on. Yes the output transformer are toroids.
The CD player is a Forsell Air reference. The top unit is the drive. It floats the CD on air and it is put in " upside down ". The other golden-black unit under it is the DA converter.
This is a huge machine but i did not find anything better until now.
With high resolution material on Amarra it sounds even better but as a CD player the Forsell is still the machine to beat.
The amps are LA Audio 6550 push-pull Class A.
They are rather old, from the early 90th but heavy modified. Better caps, new wiring that improved S/N and so on. Yes the output transformer are toroids.
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Focus? Transistor possibilities: Try BC546C/BC556C or BC560C/BC550C for all of the transistors, outputs too. The small signal transistors will probably "focus" better than miniature size drivers.
Focus? Compensation possibilities: For compensation, ah, try not to round off the square wave even if you have to leave just a really tiny peak up on the corner, aka acutance, which is like photo sharpening. A square wave that does a perfect square is preferable. However, I think that rounded/blur should be avoided.
Focus? Power circuit possibilities: Making local decoupling work with a very low cost bit of brute force, is an option. Perhaps, just put 1n4007 series between power source and C1 and also a 1n4007 series between power source and C2. I've no idea if that works for this buffer; however, forcing local decoupling to work can benefit most anything with a small signal. It should be good to use a pair of diodes for right and a different pair for left, so as to provide some privacy between the channels, aka virtual dual mono. Here is a large size example with a power amp.
P.S. I hope some of these suggestions has an enjoyably practical outcome.
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No, both channels are not the same.
One channel has the Fet and NOT the compensation, the other channel has NOT the Fet but the compensation.
The sound got even better over time by the way. That is when i have build a circuit brand new it needs some time to burn in. I assume that has to do with the electrolytics forming.
That is what i heard initially :
For example Melody Gardot on " Absence ".
The voice was further back from me as i am used too and " lower" also a bit diffuse.
After run in the voice is closer to me and more present, higher too but still not super sharp focussed.
On the positive side the sound is " softer " then with the Piglets Dad but more detailed.
For example i hear more separate violins in the back up orchestra. When that happens i know it is less distortion. At first this seems less dynamic but dynamics are restored when i crank the volume a bit. Then it is even more dynamic but also less fatiguing.
I will now make both channels the same.
I am hyper sensitive to focus and 3D effect anyway but i do not have as good tonal hearing then some.
Today Martina Schöner visits me and we will compare the Kean, the Piglets Dad and the Calvin. She has excellent tonal hearing but i am better to judge the sound stage i think.
One channel has the Fet and NOT the compensation, the other channel has NOT the Fet but the compensation.
The sound got even better over time by the way. That is when i have build a circuit brand new it needs some time to burn in. I assume that has to do with the electrolytics forming.
That is what i heard initially :
For example Melody Gardot on " Absence ".
The voice was further back from me as i am used too and " lower" also a bit diffuse.
After run in the voice is closer to me and more present, higher too but still not super sharp focussed.
On the positive side the sound is " softer " then with the Piglets Dad but more detailed.
For example i hear more separate violins in the back up orchestra. When that happens i know it is less distortion. At first this seems less dynamic but dynamics are restored when i crank the volume a bit. Then it is even more dynamic but also less fatiguing.
I will now make both channels the same.
I am hyper sensitive to focus and 3D effect anyway but i do not have as good tonal hearing then some.
Today Martina Schöner visits me and we will compare the Kean, the Piglets Dad and the Calvin. She has excellent tonal hearing but i am better to judge the sound stage i think.