Nice Ranchu..... i will try Rodd circuit
Despite we had a figth in 2004....maybe he has not figth with me...but i did related him...he was dead to me since i found he was a business man infiltrated...disquised as a diy.... well...this what i have figured out that early days...have not checked him anymore..we have two emails of conversation and them i close the door about him.
What happened in 2004?.... someone asked in this forum to help him to produce a pcboard to P3a and i have prepared..as i can do that in less than 5 minutes by hand.... i am fast doing that...as a lightning...as a flash
I have published and he criticised me because he was selling pcboards.
The old problem....forum is diy..it is for free..but always we have people trying to earn money from this forum....old problem....the first i have faced...since that moment i keep distance from Rodd..... because i felt bad with his criticism about me...this created me troubles because he is very good in audio and i have not learned anything from him as a result of our early crash.
It is fair to ask a little bit more from pcboards here...because we have expenses..cost to order first test pcboard..the photographic material to create the master..costs of software to produce layout..cost of parts to assemble prototype...cost of one unit to be assembled to show up and to make advertisement..all this enters as cost..added to the pcboard factory price and divided by the quantity of pcboards made... but more than that is profit.... people pretending not to have profit and having profit.... i dislike that stuff because put all of us in the same level....if someode does that and i also offer pcboards....people will think, imagine, suspect, that i am doing the same dirty game.
regards,
Carlos
Despite we had a figth in 2004....maybe he has not figth with me...but i did related him...he was dead to me since i found he was a business man infiltrated...disquised as a diy.... well...this what i have figured out that early days...have not checked him anymore..we have two emails of conversation and them i close the door about him.
What happened in 2004?.... someone asked in this forum to help him to produce a pcboard to P3a and i have prepared..as i can do that in less than 5 minutes by hand.... i am fast doing that...as a lightning...as a flash
I have published and he criticised me because he was selling pcboards.
The old problem....forum is diy..it is for free..but always we have people trying to earn money from this forum....old problem....the first i have faced...since that moment i keep distance from Rodd..... because i felt bad with his criticism about me...this created me troubles because he is very good in audio and i have not learned anything from him as a result of our early crash.
It is fair to ask a little bit more from pcboards here...because we have expenses..cost to order first test pcboard..the photographic material to create the master..costs of software to produce layout..cost of parts to assemble prototype...cost of one unit to be assembled to show up and to make advertisement..all this enters as cost..added to the pcboard factory price and divided by the quantity of pcboards made... but more than that is profit.... people pretending not to have profit and having profit.... i dislike that stuff because put all of us in the same level....if someode does that and i also offer pcboards....people will think, imagine, suspect, that i am doing the same dirty game.
regards,
Carlos
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The known solution to this, of course, is to split R19 in two, and take the Q7 base from the junction. The series resistor values allows the desired bias current to flow, while the lower resistor is sized to allow some (safe) higher current to operate Q7.
I'm having another look at your Blame ES schematic at Greg's website here: DX Blame ES, ST, MKII, MKII Supercharged
I think you got it right Carlos; it is going to be very difficult to improve this. It is similar to, but not exactly the same as, several amplifiers I have built based on Douglas Self's work.
I like your bootstrap circuit on the voltage amplifier - that is a nice touch.
Sometimes you can use special transistors to make something sound better. The KSC3503 is a very good VAS transistor but I don't know if you can find it in Brasil. Sometimes you can reduce the compensation capacitor for better sound. But sometimes you do it and it sounds worse or it bursts into oscillation. But I'm sure you have tried all these things!
I think you got it right Carlos; it is going to be very difficult to improve this. It is similar to, but not exactly the same as, several amplifiers I have built based on Douglas Self's work.
I like your bootstrap circuit on the voltage amplifier - that is a nice touch.
Sometimes you can use special transistors to make something sound better. The KSC3503 is a very good VAS transistor but I don't know if you can find it in Brasil. Sometimes you can reduce the compensation capacitor for better sound. But sometimes you do it and it sounds worse or it bursts into oscillation. But I'm sure you have tried all these things!
Cascodes don't work with EF2's ! Not well , at least.
"no good audible results" ... of course.
Put it behind a good EF3 or FET output stage and a cascode is as great
a "jump ahead" as the "blame" was over the original DX.
OS
OS, you should know better than to discuss EF3 in Carlos' thread!! There is something seductive about an amplifier that uses a simple bipolar EF2 output stage, driven from a single-ended VAS loaded with a simple bootstrapped current source.
I haven't had the pleasure of building the Blame ES (yet) but I'm willing to bet it sounds very good indeed, since the circuit is so close to my own circuits that I've built.
I haven't had the pleasure of building the Blame ES (yet) but I'm willing to bet it sounds very good indeed, since the circuit is so close to my own circuits that I've built.
I do like to use my desktop old style PC
It is nearby my bed, and i keep myself enjoying audio tests... Henrick speakers from Japan... Shaman from Russia and other old videos about Speaker factory tour...well..... good sound you can listen from these sites and the amplifier i am using together my computer is a Dx Blame ES with a nice homemade transmission line speaker...and sound always surprises me.
I do think it is hard to beat Blameless style amplifiers because anything can be better than perfection....and Blameless design is really very close to perfection considering amplifiers sounds almost the same...differences are very small and hard to perceive.
Here you have a test made by this guy from Nederland... i have agreed 100 percent related his judgement...but his depends on the system you gonna use to listen...if your system have not the quality, then these sequences of audio gonna sound the same as i could notice using a cheap headphone..... so.... if you perceive sound as "same"..then you should use a better amplifier and speaker to allow you a better monitoring of your computer audio.
https://www.youtube.com/watch?v=EpX2u-sGbpY
I do love Dx Blame ES
regards,
Carlos
It is nearby my bed, and i keep myself enjoying audio tests... Henrick speakers from Japan... Shaman from Russia and other old videos about Speaker factory tour...well..... good sound you can listen from these sites and the amplifier i am using together my computer is a Dx Blame ES with a nice homemade transmission line speaker...and sound always surprises me.
I do think it is hard to beat Blameless style amplifiers because anything can be better than perfection....and Blameless design is really very close to perfection considering amplifiers sounds almost the same...differences are very small and hard to perceive.
Here you have a test made by this guy from Nederland... i have agreed 100 percent related his judgement...but his depends on the system you gonna use to listen...if your system have not the quality, then these sequences of audio gonna sound the same as i could notice using a cheap headphone..... so.... if you perceive sound as "same"..then you should use a better amplifier and speaker to allow you a better monitoring of your computer audio.
https://www.youtube.com/watch?v=EpX2u-sGbpY
I do love Dx Blame ES
regards,
Carlos
Attachments
But the blames have current sources ... and these are "bad" (4 years ago).
EF3 is taboo , I know. But , EF2 restricts you to high current simple VAS's
only.
A mosfet EF2 would even be a great leap , just as simple (and more durable).
ES is a good design , my next module will be similar (hooked to a EF3😱).
OS
I could not stop it ringing with a 1kHz square wave fed in through a 0.07us input filter (1k + 68pF).
Looks a lot worse when 10kHz.
I guessed that the ringing was due to PCB layout, the ground is the type that feeds around the outside of the PCB. The ringing on that ground varies as one moves away from the test reference location.
Both assembled PCBs were the same and have been lying on the shelf for the past year.
Can you listen that ringing Andrew?
I cannot...but i understand...when things are not perfect in our mind we reject.
Fix that ringing and publish schematic related what you have done into your own pcboard.
regards,
Carlos
I cannot...but i understand...when things are not perfect in our mind we reject.
Fix that ringing and publish schematic related what you have done into your own pcboard.
regards,
Carlos
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It is fine to me Ostripper
Since you say it is a Blameless...then go ahead into your design...we cannot forget that reference..... Blameless...because this is what these circuits really are despite our good work on them.
Make modifications in yours.... i will watch and maybe gonna try it...not sure as i am doing other amplifiers now a days....not more Blameless...well, trying to beat Blameless...it is hard to beat the perfection.
regards,
Carlos
Since you say it is a Blameless...then go ahead into your design...we cannot forget that reference..... Blameless...because this is what these circuits really are despite our good work on them.
Make modifications in yours.... i will watch and maybe gonna try it...not sure as i am doing other amplifiers now a days....not more Blameless...well, trying to beat Blameless...it is hard to beat the perfection.
regards,
Carlos
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