This drives me specially happy dear Sakis
We started in this forum, several years ago in the middle of a figth... i was in between the "cross fire"...we became "bros"....i am glad you want my amplifier.
Good news.... i was sad today, daugther had problems in school because remaining in the first place these last three years.....second, third and fourth place student's parents are complaining about the school evaluation of performance system... jellows and envy attacking my daugther there.... i have asked daugther to reduce her performance to avoid problems...not to be first place once again...she didn't.... she is good in Mathematics and leadership...school students loves her..this is what drives her first place.
But now i am feeling better knowing you are with me.
regards,
Carlos
We started in this forum, several years ago in the middle of a figth... i was in between the "cross fire"...we became "bros"....i am glad you want my amplifier.
Good news.... i was sad today, daugther had problems in school because remaining in the first place these last three years.....second, third and fourth place student's parents are complaining about the school evaluation of performance system... jellows and envy attacking my daugther there.... i have asked daugther to reduce her performance to avoid problems...not to be first place once again...she didn't.... she is good in Mathematics and leadership...school students loves her..this is what drives her first place.
But now i am feeling better knowing you are with me.
regards,
Carlos
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Two more questions before I try mine:
1) I found what seems to be a very good output coil in an old IBM PC PSU. Its diameter is 7 mm, and it is 20 turns long. I'm considering in using about 12 turns. How could we estimate the best length?
2) Wired resistors (not carbon or metal film) are not welcome for the 0.22R ones, right? But, as I live almost near the end of the world, having NO parts warehouse in a 150 km radius, my only option to turn on my prototype is using these guys. What would be the difference from using them or not? I know: it is also an inductor! But I thank for more information on this issue.
Photos are "coming out of the oven", as we would say here in Brazil! haha
Max.
1) I found what seems to be a very good output coil in an old IBM PC PSU. Its diameter is 7 mm, and it is 20 turns long. I'm considering in using about 12 turns. How could we estimate the best length?
2) Wired resistors (not carbon or metal film) are not welcome for the 0.22R ones, right? But, as I live almost near the end of the world, having NO parts warehouse in a 150 km radius, my only option to turn on my prototype is using these guys. What would be the difference from using them or not? I know: it is also an inductor! But I thank for more information on this issue.
Photos are "coming out of the oven", as we would say here in Brazil! haha
Max.
Welcome Mr. Sakis, from Greece! We have met in the Rod Elliot's P3A thread!
Due to the PCB bruhaha, I gave up and decided to enter Mr. Carlos' project thread.
I have already assembled 80% of 2 full boards, expecting to have them tested by the end of this week (I must attend to my job also!!!).
Best regards,
Max.
Due to the PCB bruhaha, I gave up and decided to enter Mr. Carlos' project thread.
I have already assembled 80% of 2 full boards, expecting to have them tested by the end of this week (I must attend to my job also!!!).
Best regards,
Max.
Observe this group buy Nico opened some years ago, to HRII
Was in September 2007
You will see how many folks have ordered, and you will see names that still are in our forum, as Meanman for instance.
I was already in the correct track.... following the good clues....the HRII looks alike the Dx Blame ES...take a good look at the schematic and observe they are not too much different....it is the second in audio quality to the trebles...the second in audio quality to the bass is the Precision 1..the one is globaly the best is the Dx Blame ES...beating my amplifiers in everything.
http://www.diyaudio.com/forums/group-buys/108456-destroyer-x-amplifier-dx-hdii-version.html
regards,
Carlos
Was in September 2007
You will see how many folks have ordered, and you will see names that still are in our forum, as Meanman for instance.
I was already in the correct track.... following the good clues....the HRII looks alike the Dx Blame ES...take a good look at the schematic and observe they are not too much different....it is the second in audio quality to the trebles...the second in audio quality to the bass is the Precision 1..the one is globaly the best is the Dx Blame ES...beating my amplifiers in everything.
http://www.diyaudio.com/forums/group-buys/108456-destroyer-x-amplifier-dx-hdii-version.html
regards,
Carlos
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would you be kind enough to explain what is a PCB bruhaha ??? it sounds funny to me but it seems that my english is not enough for that
Bruhaha
(from online dictionary) Bruhaha: a fight or some kind of argument between more than just two people. This specific kind of fight is usually just verbal because when it's physical, it becomes a bruhehe.
Well, English is not easy for me too, but I try to do my best!
I think there was too much mystic about the design of a PCB there, and here I found a less difficult way to achieve my goal of constructing a homemade 100W amplifier. Comparing P3A and DX amp, I saw that a few parts more wouldn't be any trouble, in spite of acquiring a better result.
Maybe some day I will be able to test all the projects in the forum!!! But don't have all the time that would be necessary!
For this reason I decided to join this group, and elected DX Blame ST as MY FIRST HOMEMADE 100W AMPLIFIER! (first 100W...).
I hope to be able to help as well, not only ask questions...
Greetings from Brazil.
Max.
would you be kind enough to explain what is a PCB bruhaha ??? it sounds funny to me but it seems that my english is not enough for that
(from online dictionary) Bruhaha: a fight or some kind of argument between more than just two people. This specific kind of fight is usually just verbal because when it's physical, it becomes a bruhehe.
Well, English is not easy for me too, but I try to do my best!
I think there was too much mystic about the design of a PCB there, and here I found a less difficult way to achieve my goal of constructing a homemade 100W amplifier. Comparing P3A and DX amp, I saw that a few parts more wouldn't be any trouble, in spite of acquiring a better result.
Maybe some day I will be able to test all the projects in the forum!!! But don't have all the time that would be necessary!
For this reason I decided to join this group, and elected DX Blame ST as MY FIRST HOMEMADE 100W AMPLIFIER! (first 100W...).
I hope to be able to help as well, not only ask questions...
Greetings from Brazil.
Max.
that was very nice max...i enjoyed having a bruhaha with you ....
I wish you succes to your amplifier built ...i will look forward to see pictures and compaire to the one i built
happy joyfull regards sakis
i am more wise now that i know what was a bruhaha and a bruhehe ....it is still sounds very funny
I wish you succes to your amplifier built ...i will look forward to see pictures and compaire to the one i built
happy joyfull regards sakis
i am more wise now that i know what was a bruhaha and a bruhehe ....it is still sounds very funny
Smartx21..... your IBM supply coil will be good... 20 turns
and 7 milimeters diameter if air core... if has a core, then remove it.
knowing your wire diameter in AWG, them enter here.... from 2uH to 4uH is fine:
http://colomar.com/Shavano/inductor_info.html
regards,
Carlos
and 7 milimeters diameter if air core... if has a core, then remove it.
knowing your wire diameter in AWG, them enter here.... from 2uH to 4uH is fine:
http://colomar.com/Shavano/inductor_info.html
regards,
Carlos
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Air core is important..if your coil has a ferrite inside..then remove it
ferrite, or iron core, depending how big is the current, saturates and generates noises in the audio reproduction..also increases the resultant inductance..so..the 22 turns, having 7 milimeters diameter, if have ferrite core inside, in the place to air core, will jump high in inductance value.
regards,
Carlos
ferrite, or iron core, depending how big is the current, saturates and generates noises in the audio reproduction..also increases the resultant inductance..so..the 22 turns, having 7 milimeters diameter, if have ferrite core inside, in the place to air core, will jump high in inductance value.
regards,
Carlos
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I saw that, but I supressed that part of the text, for obvious reasons!!!
hahahahahahahaha
Dx amplifier...this one will make you dance!
Be happy!, build a Dx amplifier.... a guarantee of enjoyment!
YouTube - Where the Hell is Matt? (2008)
Have you got the spirit?
Carlos
Be happy!, build a Dx amplifier.... a guarantee of enjoyment!
YouTube - Where the Hell is Matt? (2008)
Have you got the spirit?
Carlos
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VBE multiplier, the heat sensor, what transistor is good there?
Several friends, all them Dx Builders, have asked me these last monthes about the VBE multiplier...as they do that using direct mail, i see they feel ashamed to ask that in our forum..so, others may have these doubts too...reason why i will publish this text used as answer to one of them...i may not be 100 percent correct in some details, as i am a builder, not a scientist or engineer..all i know was learned building and burning my fingers..i hope this will help:
VBE multiplier is a dinamic resistance.. it behaves alike a NTC resistance...negative thermistance, so..when hot, reduce its resistance that will have, as a consequence, a reduction in the voltage developed in the NTC extremes..reducing this way the bias that is 2.5 volts going to be a a smaller voltage, this reduces the stand by bias point, the current reduces
The stand bias affect the whole amplifier performance..alike the 900 rpm you have in your car when not engaged, when iddle, when in stand by mode... if your car is acelerated this changes it’s behavior when you change speed in your gear box..also change your break performance as it will nto reduce the speed so easily when you remove your feet from the acelerator pedal...happens the same to the VBE multiplier.
It is a variable resistance..an adjustable one..the base to emitter resistance allows you to adjust the colector to emitter resistance...it does not make dinamic amplification or modulation of the audio..it is saturated... when transistor is saturated, or almost saturated, it does not swing or swing a very little only....audio crossed, as behave as resistance and it is bi-directional.
The VBE multiplier is in saturation, so, not variations in DC or AC happens because of some audio that enters the VBE multiplier base....almost no audio amplification..saturated!..almost anything happens...it is just a series resistance (the colector to emitter junction) where the VAS current goes through ,and the main function is to develop, behaving as a variable resistance, a NTC one, that will adjust the 2.4 volts needed to bias the 4 output transistor bases, as in common emitter you have four diodes (base to emitter junctions) connected to the output line (zero volt) and this should develop, or maintain, 600 milivolts to each one of them...so...600 milivolts multiplied by 4 results in 2.4 volts.
So...the main function is to receive heat and to have it's internal resistance reduced, in order to reduce the voltage drop from colector to emitter, reducing the 2.4 volts to a lower resistance that will reduce the output transistors stand by current too.
There, in the VBE multiplier, you have only 2.4 volts..so..almost all wide world NPN transistor will work there... there's no need of gain, there's no need of high current as we do not use high current there, there's no need to face high voltages, as there's no high voltages there... there’s not need of high frequency operation as it does not work dinamically, or operate almost nothing dinamically..very small swing..caused by this transistor....any NPN can be installed there... the size you want, the type you want, the model you want...BD135 and BD139 plus a zillion of transistors will work there and will perform the same...the gain may change the trimpot adjustment settings, to obtain the colector to emitter resistance you want..just that.
Power transistors, as 2SC5200, MJE4315, 2SC3281, MJl21194, 2SC2922...all them sound almost the same in the output..difference in audio is very small... advantage may be nice to dissipation in the 2SC2922...maybe more gain in the MJE4315.... some small treble advantage to the 2SC2922..but difference is so small that we can believe they are almost the same.
Some guys perceive the 2SC5200 a little bit mufled compared to the 2SC2922...this is real..we
can perceive, not easy to perceive that switching from one to the other..but we can perceive a
very small difference in treble level..only level...something you can obtain the same effect increasing your tone control 1 to 2 decibels up..hard..very hard to perceive... so..if you can
compensate this..turning the treble knob, ore increasing the tweeter capacitor, or reducing the tweeter series resistance..not needed to worry about..it is inside the chapter of “tollerances” and
small variations that happens in the analog audio electronic field
regards,
Carlos
Several friends, all them Dx Builders, have asked me these last monthes about the VBE multiplier...as they do that using direct mail, i see they feel ashamed to ask that in our forum..so, others may have these doubts too...reason why i will publish this text used as answer to one of them...i may not be 100 percent correct in some details, as i am a builder, not a scientist or engineer..all i know was learned building and burning my fingers..i hope this will help:
VBE multiplier is a dinamic resistance.. it behaves alike a NTC resistance...negative thermistance, so..when hot, reduce its resistance that will have, as a consequence, a reduction in the voltage developed in the NTC extremes..reducing this way the bias that is 2.5 volts going to be a a smaller voltage, this reduces the stand by bias point, the current reduces
The stand bias affect the whole amplifier performance..alike the 900 rpm you have in your car when not engaged, when iddle, when in stand by mode... if your car is acelerated this changes it’s behavior when you change speed in your gear box..also change your break performance as it will nto reduce the speed so easily when you remove your feet from the acelerator pedal...happens the same to the VBE multiplier.
It is a variable resistance..an adjustable one..the base to emitter resistance allows you to adjust the colector to emitter resistance...it does not make dinamic amplification or modulation of the audio..it is saturated... when transistor is saturated, or almost saturated, it does not swing or swing a very little only....audio crossed, as behave as resistance and it is bi-directional.
The VBE multiplier is in saturation, so, not variations in DC or AC happens because of some audio that enters the VBE multiplier base....almost no audio amplification..saturated!..almost anything happens...it is just a series resistance (the colector to emitter junction) where the VAS current goes through ,and the main function is to develop, behaving as a variable resistance, a NTC one, that will adjust the 2.4 volts needed to bias the 4 output transistor bases, as in common emitter you have four diodes (base to emitter junctions) connected to the output line (zero volt) and this should develop, or maintain, 600 milivolts to each one of them...so...600 milivolts multiplied by 4 results in 2.4 volts.
So...the main function is to receive heat and to have it's internal resistance reduced, in order to reduce the voltage drop from colector to emitter, reducing the 2.4 volts to a lower resistance that will reduce the output transistors stand by current too.
There, in the VBE multiplier, you have only 2.4 volts..so..almost all wide world NPN transistor will work there... there's no need of gain, there's no need of high current as we do not use high current there, there's no need to face high voltages, as there's no high voltages there... there’s not need of high frequency operation as it does not work dinamically, or operate almost nothing dinamically..very small swing..caused by this transistor....any NPN can be installed there... the size you want, the type you want, the model you want...BD135 and BD139 plus a zillion of transistors will work there and will perform the same...the gain may change the trimpot adjustment settings, to obtain the colector to emitter resistance you want..just that.
Power transistors, as 2SC5200, MJE4315, 2SC3281, MJl21194, 2SC2922...all them sound almost the same in the output..difference in audio is very small... advantage may be nice to dissipation in the 2SC2922...maybe more gain in the MJE4315.... some small treble advantage to the 2SC2922..but difference is so small that we can believe they are almost the same.
Some guys perceive the 2SC5200 a little bit mufled compared to the 2SC2922...this is real..we
can perceive, not easy to perceive that switching from one to the other..but we can perceive a
very small difference in treble level..only level...something you can obtain the same effect increasing your tone control 1 to 2 decibels up..hard..very hard to perceive... so..if you can
compensate this..turning the treble knob, ore increasing the tweeter capacitor, or reducing the tweeter series resistance..not needed to worry about..it is inside the chapter of “tollerances” and
small variations that happens in the analog audio electronic field
regards,
Carlos
I feel that i was, a long time ago, sniffing the good circuit
The HRII has almost the same style of differential....not using CCS.
The HRII used the same enhanced VAS circuit..not using the better value to the first VAS emitter resistance.
The HRII used bootstrapp, with different "calibration" but used bootstrapp... and the output is the same.
That's the reason why it is the second in audio quality from the Dx amplifiers.
I am proud to remember this one..very proud of it...i was already "feeling"... sniffing, the good one.
I am very happy about myself..in peace with my soul, as i am following a progressive sequence of amplifiers, that resulted in something so good as this one offered to you to assemble... the Dx Blame ES/ST... a mature amplifier that had a history where several forum friends took his part on that.
regards,
Carlos
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The HRII has almost the same style of differential....not using CCS.
The HRII used the same enhanced VAS circuit..not using the better value to the first VAS emitter resistance.
The HRII used bootstrapp, with different "calibration" but used bootstrapp... and the output is the same.
That's the reason why it is the second in audio quality from the Dx amplifiers.
I am proud to remember this one..very proud of it...i was already "feeling"... sniffing, the good one.
I am very happy about myself..in peace with my soul, as i am following a progressive sequence of amplifiers, that resulted in something so good as this one offered to you to assemble... the Dx Blame ES/ST... a mature amplifier that had a history where several forum friends took his part on that.
regards,
Carlos
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