Dx Blame ES .... based into the Blameless, i am trying a new amplifier

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There are some lazy folks into my Orkut group

Because of that i have made a fast sketch to them, how to produce a board in 20 minutes just watching the schematic.

This is to be assemble copper side,but there's no problem to invert and to use the traditional way, producing holes into the board.

regards,

Carlos
 

Attachments

  • Fast layout.pdf
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  • Copper lines.pdf
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Soon a pretty schematic made by Taj, he use to be the Dx Corporation main

layout and pcboard designer.

To the pcboard we have other cooperators, but they seem are not visiting the forum anymore.

Will ask Taj the pcboard as soon as he finishes the schematic layout.... but i am afraid the pcboard, the professional one, will not be ready before Christmas.

regards,

Carlos
 
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The preliminary, temporary, draft pcboard offered was made for my Orkut friends

Soon we gonna have something professional, my Orkut group have not demanding people, they want to build and listen, they do not mind about how the things looks....of course they love pretty things, but this is not priority for them (not for me too).

The dimensions are 3.6 inches by 3.0 inches, or 90 by 78 milimeters

regards,

Carlos
 
These are the copper tracks, i do not think this is good enougth but works!

Soon we gonna have something better.

This is "just in case" nobody presents to help, first one in the list is Taj.

regards,

Carlos
 

Attachments

  • Dx Blame ES copper tracks.jpg
    Dx Blame ES copper tracks.jpg
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How it is sounding to me

Crispy detailed high frequencies, reproducing the tone and all harmonics that show us the type of instrument is beeing played (timbre)

Bass is tigth, strong, deep and controlled, not so deep and loosen as the Dx Standard and not so week alike the HRII, maybe alike the Precision 1

Voices are normal, fair and present, low midranges are specially detailed, so, drums and percursive instruments appear more clear than normal.

Of course the amplifier is flat, but this does not matter, the speaker is not, also my ears are not, my room also is not flat and the recording is not flat too...but even if you had all that stuff flat, some tones appear more clear in one amplifier compared to the other.... a interesting stuff, some sonic character that each amplifier has.

Interesting are the detailed highs, the best result i could have, so, this Blameless from end, the increasing in current, the good tuning and good tweak made resulted fine... there are some instruments i am now perceiving...something new to me, only the Techno by Bora gave me that nice perception of new instruments into the old music.

My recordings are awfull, the camera microphone is not good anymore, noisy and having losses into the high end.

The bass is alike the Krill, a lovely amplifier.

The treble, let me see how to compare...hmmmm, maybe better than the Techno, but it is hard to say without compare.

The most interesting thing, it surprises, seems to have more power than really has, for a 39 volts amplifier it is pumping the normal power, something alike 60 and 110 watts (8 and 4 ohms), but looks twice.

Dinamics are impressive, and the distortion is really small, not only numbers, really appeared less distorsive in special when you increase the volume till the top, seems it controls better, the feedback is controling in a such way the distortion enters in a very soft way.... plays loud alike the HRII, the one also pumps a hell loud for the power rated.

No power on thump, because the CCS and small condensers into the input circuitry, power off is silent too.

Works dead cold, no one is hot, nothing warmer than our environment temperature, exception is the output of course.

Wave forms are almost perfect.

Is it a miracle?.... no!.... but it is better than almost all amplifiers i have tested related distortion and clarity of instruments reproduced..... say..you can listen each instrument, different than other amplifiers that mix alll that thing and you cannot concentrate your attention into some particular instrument playing.

What has that may be the main advantage?

Dinamics, very special focus, instruments does not appear mixed with others, you can listen each one of them, low distortion, low noise and super clear high frequencies... detailed drums, and percursive instruments, more controled bass, but has that looong bass tone is like (bootstrapp)

What i dislike?

Compression (HRII do the same.. and krill does to lower levels too), seems has a compressor entering at normal levels, seems you have peaks but the normal musical program plays almost same level...some compressor adjusted not to compress very low levels and not to work into high levels.... maybe the sensitivity have to be adjusted better, that 500 ohms gain resistance.

My Orkut group will build... some of them already started.... if you have already build a Dx amplifier model, you will perceive this as better in overall performance.

May exist better reproduction?... for sure, the astounding treble i have listened from a tube Macintosh (1974) amplifier.... i have never listened again...maybe my ears are not more good enougth to listen those tones.

Also,... almost all amplifier plays a nice sound, the difference comparing the average one with the best one is not so huge...amplifiers if well biased, say, not rude errors into the design, not errors in current, VBEs in levels, then will play a good sound...speaker makes more difference into sonics than the amplifiers.

Was tested full power, over 7 ohms in parallel with 2.2uf..... of course became hot and i had the need of a fan to help the unit, but survived, i am not sure about how will behave facing 4 ohms, will test that soon.

regards,

Carlos
 
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I had a very hard time with this amplifier while tweaking

If you remove one or two of the capacitors shown, for sure it will oscilate, in special the one with blue arrow.

I have lost several BD139, BD140 and one FJL4315.... when oscilating the base voltage is bigger than the maximum base to emitter voltage and the transistor burns.

Also if you forget to ground the heatsinks, when you touch bases with your AC voltimeter, the the amplifier will oscilate and the consumption will jump to several amperes..you will be forced to switch the power off (ahahahah, reset?) to reconstitute the stability.

Well, amplifiers are oscilators, input signal tracked oscilator, as the amplifier oscilates from positive to negative, but we want the unit to oscilate when you have audio entering...not different than that.

So, it is an unstable stability.

When oscilating you may be fooled, AC can be measure as DC into the output, you may think you have off set troubles, when in the reality the voltage you have is Radio Frequency, oscilations, rectified by your instrument sensitivity.

The bias trimpot starts not to operate correctly, you cannot adjust properly, you go increasing current reading over the 10 ohms series protective resistance and them the voltage jumped to several volts that means several amperes...and you try to return and nothing works..very crazy thing.... carefull with that stuff, bias control not operating properly means oscilations (or builder errors into the construction)

Carefull with this beauty!..... it loves to oscilate, the CCS into the input use to produce this effect... the amplifier turns easy to oscilate, or, at least the ones i have tried using CCS were sensitive to oscilations.....short wires, small length to transistors, ground into the heatsink and do not forget to install capacitors, the red marked ones are the main ones.

regards,

Carlos
 

Attachments

  • Oscilation is possible.gif
    Oscilation is possible.gif
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I do not know Ultima

The one was very helpfull to stop oscilations.

If you observe the image posted you gonna see the waveshape is perfect for a sinusoidal signal at 100 kilohertz, full power. Also the THD is very, very low.

So, right or wrong is working fine, and this is what matters, to confirm theories or beliefs is secondary to me.

Please, stop before start to search for errors, try to observe the qualities. be positive Ultima. The amplifier was not posted for technicall revision, was posted to builders.

bye,

Carlos
 
Ahahahaha.... it is all rigth.... old folk mood is a little bit variable

The amplifier is stable Ultima.

Receive a hug and 2 kisses, in special if you have pretty daugthers!

Have not?... so kisses are removed!

YouTube - Stable

When the amplifier is not stable, when you put your finger tip mains generator, then a lot of Heterodyne beatings appear, the sound sounds alike a Radio Amateur tunning a SSB receiver when an AM carrier is present. chirps and strange noises happens.

Finger-O-generator is a recently developed instrument made by the Corporation, the mains wire propagates radio frequency into a Very Low Frequency band, your body behaves alike an antenna because you have watter an iron in your blood, so the mains frequency is captured by your body, when you touch the power amplifier input, the your Finger-o-generator
releases the tone that is amplifier by your power amplifier and reproduced by your speakers.... Finger-0-generator is a registered brand from the Corporation (ahahahahaha!)

regards,

Carlos
 
Yes, i found errors, and the VBE multiplier returned to the standard mode

It is working fine this way those last years, will not try the new circuit.

Team that is winning, we do not make changes or player's substitution!

here you have the new images..sorry by the quality, but i think we gonna have a better board design soon, this one is a previous one offered to my orkut friends that are daily chatting with me, so they can ask me things and i can inform them the last modifications made.

regards,

Carlos
 

Attachments

  • Dx Blame ES - to publish.pdf
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  • Dx Blame ES copper tracks.pdf
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  • Ray X vision - transparência.pdf
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100pF from base of VAS "beta enhancer" to ground seems to me not a good idea..Straight way for hf disturbancies and possible stability problems. Use bigger value instead 33pF Cdom..And resistor about 1Megaohm in parallel with this capacitor will lower VAS gain (lower OLG-better stability) but at the same time you gain much better VAS linearity and lower VAS output impedance..
 
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A profissional pcboard layout will be provide by Taj along monthes

of January and february...for a while, if you want to assemble, create your own board or use the one i have provided to my Orkut friends (the ugly one).

Failure into board layout design, when made by me, is always an option.

Better do to yours.

The amplifier is a hell sensitive to oscilations, i have lost several transistors when first time powering and tweaking.... make changes under your own risk and do not came to complain to the Corporation if something was modified.

Reliability is guaranteed the way it is.

The design will not be changed, was tested, working fine, sounding fine.... i have only to continue the endurance test to 4 ohms till wednesday.... the unit is playing all time long, loaded to be unstable and speaker connected together the crazy load (in series with a small resistance)...only schematic errors, wrong values (typping error), lines missed into schematic, well, those things may be fixed.

The amplifier is not opened to suggestions how to make it better.... the one can make it better can do it by himself opening a dedicated thread for this purpose.

regards,

Carlos
 
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