It is all rigth... all cleaned...i also do not know
So...be happy and enjoy your amplifier.
regards,
My world
So...be happy and enjoy your amplifier.
regards,
My world
I don't know why current mirrors on top of LTP sound like crap, but they do. Maybe I've implemented them in a bad way. I've just tried it with 100R emitter resistors. Maybe it's that memory distortion thing, and far higher resistance should be used.Lumba Ogir said:
In my folded cascode amp where I use improved Wilson mirrors on "the bottom" of the common-base transistors, the sound improved when I changed the emitter resistance from 50R to 250R.
And Lumba, you were wrong when you said this little amp was stillborn. It sounds almost perfect now. Just slightly warm, and I think it's because of the "lowish" voltage drop over the diodes to the common-base transistors. With a larger drop, 4.7V, the sound is brighter, and in LTSpice I can see a good reduction of 2nd order harmonic. But this larger drop the amp's not good as a portable device due to the lowered voltage swing.
the best amplifier is the one you like the sound of best, its as simple as that.
its a tool to enjoy music with
its a tool to enjoy music with
Hi Nelson,
quite many people are of that opinion, It`s not memory distortion nor your implementation, rather the increased open-loop gain.
Your amp is pretty nice now, is it portable?
quite many people are of that opinion, It`s not memory distortion nor your implementation, rather the increased open-loop gain.
Your amp is pretty nice now, is it portable?
Yes... this is reality..the best amplifier is the one you like the most
Also the best woman is the one you love the most...she can be ugly alike a truck crash against a wall, she can be more fat then a fat bear... she can be stupid as a donkey...if you love her.... everything gonna be all rigth.
The big magic is the passion, the love we feel...love is the answer.
Nice Lineup..very nice!
thank you.... i felt good knowing you are happy.
Carlos
Also the best woman is the one you love the most...she can be ugly alike a truck crash against a wall, she can be more fat then a fat bear... she can be stupid as a donkey...if you love her.... everything gonna be all rigth.
The big magic is the passion, the love we feel...love is the answer.
Nice Lineup..very nice!
thank you.... i felt good knowing you are happy.
Carlos
Lumba Ogir said:
Yes it's portable. I use it with a DAP and Sennheiser HD650 while doing the dishes or other boring household work. In the long run I always prefer discrete class A to chipamps. I guess Carlos would call it muffled, I think it's closer to the truth and for sure it's less fatiguing.
I'm not really convinced it's all about OLG, are you?
Nelson,
I assumed it was more serious, partially justifies the choice of topology.
I cannot see any other deteriorating parameter.
It was clear from the beginning that it was going to be portable. I am serious about it though.Lumba Ogir said:
I've tried to lower OLG and increase OL BW by increasing the LTP's degeneration resistors and used local or nested feedback loops. Not only in this amp. None of these tweaks alter the sound as much as the use of current mirrors. The transistors used for current mirrors, SA970, BC550 or BC560, have had exactly the same Hfe and have been taped togeter for temperature stability. I've tried it with no or 100R emitter resistors.
Ahahah...nice to see you research things into the minimum details
this is good...and may be interesting if i could understand your high level conversation..... i cannot.
If you have time, make a favor to the poor mortal here...i would like to know if anjos have sex or not....because if there's no girls into the heaven i will prefer to go to the hell.
ahahaha....be happy folks.
enjoy the thread....as you try to discover everything.... find that for me please.
regards,
Carlos
this is good...and may be interesting if i could understand your high level conversation..... i cannot.
If you have time, make a favor to the poor mortal here...i would like to know if anjos have sex or not....because if there's no girls into the heaven i will prefer to go to the hell.
ahahaha....be happy folks.
enjoy the thread....as you try to discover everything.... find that for me please.
regards,
Carlos
Totally accepted with carlos. you have mentioned STK from sanyo,kenwood, yamaha,sony ..... all japanese.
still few more like Rotel and Onkyo also use the same topology. they too japanese.
there can be even more manufacturers using the same. but what i have mentioned is limited to my knowledge.
Hugh Deans amplifier topology is the best.
Suresh.
still few more like Rotel and Onkyo also use the same topology. they too japanese.
there can be even more manufacturers using the same. but what i have mentioned is limited to my knowledge.
Hugh Deans amplifier topology is the best.
Suresh.
Suresh,
I do not believe the AKSA topology is the best, but it is widely used since Harry Lin and Arthur Bailey used it in the fifties and sixties. It is a road well travelled, and possible to refine it to very good performance.
However, if you want to extract more performance, you need to go down the zero distortion path, the traditional engineering approach. For this you need to examine and refine further - which means considerable added complexity - each and every circuit block; input stage, VAS, and output stage.
This all adds complexity, and of course component count. It is still a direct coupled Class AB topology, but for 100W into 8R you need about 16 transistors, which is getting pretty serious. Further refinements to the output stage add still more devices, at least another four.
Such is the complexity that you are then well advised to examine Neslon Pass' circuits. He achieves astonishing performance levels from simple topologies, mostly by very clever design and well chosen operating points. I favour his single ended designs. It is not for nothing this man is so highly regarded; his comprehension of the entire process of recorded music is amongst the clearest I have ever seen and his dedication to the DIY ethic is legendary.
Cheers,
Hugh
I do not believe the AKSA topology is the best, but it is widely used since Harry Lin and Arthur Bailey used it in the fifties and sixties. It is a road well travelled, and possible to refine it to very good performance.
However, if you want to extract more performance, you need to go down the zero distortion path, the traditional engineering approach. For this you need to examine and refine further - which means considerable added complexity - each and every circuit block; input stage, VAS, and output stage.
This all adds complexity, and of course component count. It is still a direct coupled Class AB topology, but for 100W into 8R you need about 16 transistors, which is getting pretty serious. Further refinements to the output stage add still more devices, at least another four.
Such is the complexity that you are then well advised to examine Neslon Pass' circuits. He achieves astonishing performance levels from simple topologies, mostly by very clever design and well chosen operating points. I favour his single ended designs. It is not for nothing this man is so highly regarded; his comprehension of the entire process of recorded music is amongst the clearest I have ever seen and his dedication to the DIY ethic is legendary.
Cheers,
Hugh
If he said...he may be rigth... at least all things he said i have tested
and resulted truth.
So... i imagine, once more, he may be rigth.
regards,
Carlos
and resulted truth.
So... i imagine, once more, he may be rigth.
regards,
Carlos
Give yourself a gift.... take this basic topologie
This one from Duncan.... well..... belongs to the whole world, it is the very basic three stage amplifier, alike Aksa and many others.
And do it the way you want...the way i have made to myself...a pitty was that i could not beat Aksa 55.
But maybe you can be happy not comparing with the 55.....adjust it to "your way"..... make it "your style"...do it yourself..... basic Universal topologie made by YOU.
Adjust current, try different currents.... try different voltages, try CCS and rail regulators and power regulators and mirrors, double this amplifier, use it bridged, try double simetrical input, install three or two stages VAS.... try different current to drivers, try many classes of operation, try current sinks, mirrors, CCS into the VAS and into the drivers.... try all you know, all you can and be happy beeing a real DIYer.
Try new input, new differential.... test options offered by some guys in this forum..check them and i hope you do not turn deceptive with those folks.... try new ideas to feedback, multiple feedback, local feedback, NFB, multiple feedback...all stages with feedback,...none feedback...try slow transistors and fast transistors..then install FET to see if you like them....try class A ....well....you have the whole world in front of you to explore.
BUT PLEASE..... MOVE!
regards,
Carlos
This one from Duncan.... well..... belongs to the whole world, it is the very basic three stage amplifier, alike Aksa and many others.
And do it the way you want...the way i have made to myself...a pitty was that i could not beat Aksa 55.
But maybe you can be happy not comparing with the 55.....adjust it to "your way"..... make it "your style"...do it yourself..... basic Universal topologie made by YOU.
Adjust current, try different currents.... try different voltages, try CCS and rail regulators and power regulators and mirrors, double this amplifier, use it bridged, try double simetrical input, install three or two stages VAS.... try different current to drivers, try many classes of operation, try current sinks, mirrors, CCS into the VAS and into the drivers.... try all you know, all you can and be happy beeing a real DIYer.
Try new input, new differential.... test options offered by some guys in this forum..check them and i hope you do not turn deceptive with those folks.... try new ideas to feedback, multiple feedback, local feedback, NFB, multiple feedback...all stages with feedback,...none feedback...try slow transistors and fast transistors..then install FET to see if you like them....try class A ....well....you have the whole world in front of you to explore.
BUT PLEASE..... MOVE!
regards,
Carlos
Attachments
now a question for carlos
to see his understanding of amplifiers
why we often see one PNP input pair?
... and not so often NPN, which are more of, and so much more choices for
i bet you can not figure this one out, dx 😉
to see his understanding of amplifiers
why we often see one PNP input pair?
... and not so often NPN, which are more of, and so much more choices for
i bet you can not figure this one out, dx 😉
I use PNP transistors into the differential because they
have more gain than the NPN complementary part.
I do not know the reasons others use PNP or even NPN.... all i know is this... because gain only.
This question is great.... i hope there are other reasons and this is a good chance to me to learn that.
Unfortunatelly Lineup, the guys that has master degree or college degrees, many of them around the clock consultants that runs to the threads to point errors or correct mistakes, do not have the same pleasure to help us, to give us more know how and explain us things... they seems that loves to criticise and to point our failures...and never enter when needed to give us important informations alike that.
Into this forum i have never readed something alike that.... people teaching this to us, but i have readed hundreds of intervenctions showing errors, mistakes and problems...always negative things, never contributing with us...only trying to say:
"You see...i know that and you do not know that.... you see..i am rigth and you wrong!"
I hope this time they arrive to teach us things despite to be bothering all time long.... beeing bad and hidden behing the cover of full time consultant helping poor animals against produce mistakes.
You are cooperative Lineup, you usually behave humble and it is rarity when you are boring or provocative.... this happens rarely with you...also this is rare in my person too. (well..nobody is perfect..sometimes i am bad too)
regards,
Carlos
have more gain than the NPN complementary part.
I do not know the reasons others use PNP or even NPN.... all i know is this... because gain only.
This question is great.... i hope there are other reasons and this is a good chance to me to learn that.
Unfortunatelly Lineup, the guys that has master degree or college degrees, many of them around the clock consultants that runs to the threads to point errors or correct mistakes, do not have the same pleasure to help us, to give us more know how and explain us things... they seems that loves to criticise and to point our failures...and never enter when needed to give us important informations alike that.
Into this forum i have never readed something alike that.... people teaching this to us, but i have readed hundreds of intervenctions showing errors, mistakes and problems...always negative things, never contributing with us...only trying to say:
"You see...i know that and you do not know that.... you see..i am rigth and you wrong!"
I hope this time they arrive to teach us things despite to be bothering all time long.... beeing bad and hidden behing the cover of full time consultant helping poor animals against produce mistakes.
You are cooperative Lineup, you usually behave humble and it is rarity when you are boring or provocative.... this happens rarely with you...also this is rare in my person too. (well..nobody is perfect..sometimes i am bad too)
regards,
Carlos
Has anyone played around with the Bryston output topology (it seems so symetrical: the output current is shared by an idetical NPN/PNP pair both pushing and pulling) I know these OP trannys need some matching but is that a problem?
Yes...better to use PNP Vas.
You know Lineup and forum folks... all my life was a struggle against people that won't to teach things...since the early beginning of my professional life into the biggest Brazilian Television Network (Globo Network) i had to learn by myself...people when had information use to keept with themselves.... they had into imagination that knowing more than others they would have the power.
I had passed many nigths studying manuals, Video Tape manuals, operation and maintenance manuals.... and i was not good into electronics (i am still not very good) and i had not English language knowledge...was hard to translate using dictionaire...was the way i had to open a hole into the "wall" the clever folks have built, to protect them against possible competition..so... the good thing to them was to keep personnel ignorant to dominate them with higher level of knowledge...but i did it and prepared other folks to face them too.
I have learned by myself and have climbed all position into the Engineering area till the Vice Director position...and when i reach the position i have finished with that behavior producing a school, and them everybody knew everything, and for free... for TV Professional and young candidates to enter the profession.... i have finished with that...and i am proud i have created thousands professionals into Television Broadcasting.
Now i am doing that into the Orkut, against the audio secrets, the design secrets are beeing offered to brazilians, for free... and this have high value here, as our amplifiers are copies from foreigner circuits..people do not know how to design...imagine that!... the ones that knows, do not teach anybody.....but...i am still working...this will finish... wait more 5 years and they will see that too.
I really hate those folks that behaves badly... selfish guys... and i am very sensitive to those things.
regards,
Carlos
You know Lineup and forum folks... all my life was a struggle against people that won't to teach things...since the early beginning of my professional life into the biggest Brazilian Television Network (Globo Network) i had to learn by myself...people when had information use to keept with themselves.... they had into imagination that knowing more than others they would have the power.
I had passed many nigths studying manuals, Video Tape manuals, operation and maintenance manuals.... and i was not good into electronics (i am still not very good) and i had not English language knowledge...was hard to translate using dictionaire...was the way i had to open a hole into the "wall" the clever folks have built, to protect them against possible competition..so... the good thing to them was to keep personnel ignorant to dominate them with higher level of knowledge...but i did it and prepared other folks to face them too.
I have learned by myself and have climbed all position into the Engineering area till the Vice Director position...and when i reach the position i have finished with that behavior producing a school, and them everybody knew everything, and for free... for TV Professional and young candidates to enter the profession.... i have finished with that...and i am proud i have created thousands professionals into Television Broadcasting.
Now i am doing that into the Orkut, against the audio secrets, the design secrets are beeing offered to brazilians, for free... and this have high value here, as our amplifiers are copies from foreigner circuits..people do not know how to design...imagine that!... the ones that knows, do not teach anybody.....but...i am still working...this will finish... wait more 5 years and they will see that too.
I really hate those folks that behaves badly... selfish guys... and i am very sensitive to those things.
regards,
Carlos
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