My "audiophile" LM3886 approach

"M" for Mauro

Hi Mauro,

after some days listening with my dual Rev C i want to thank you expressly for sharing this great design. By time I bought and built several amps (and some of them were really expansive), but with none of them I was nearly as happy as with my "Mauro".

So take this, painted on my amp´s chassis, as an appreciation:

An externally hosted image should be here but it was not working when we last tested it.


Cheers, Gerd
 
Re: "M" for Mauro

SmellOfPoo said:
Hi Mauro,

after some days listening with my dual Rev C i want to thank you expressly for sharing this great design. By time I bought and built several amps (and some of them were really expansive), but with none of them I was nearly as happy as with my "Mauro".

So take this, painted on my amp�s chassis, as an appreciation:

An externally hosted image should be here but it was not working when we last tested it.


Cheers, Gerd

Bravo!!!! Credit where credit is due. :yes:

Cheers!
Russ
 
"and no-one is wrong"

The only people who are wrong are those that cannot carry out a conversation without flinging personal attacks insults and the like around. That is detestable.

Mauro - it has been very kind of you to share your work, please don't stop. You have to justify yourself to no-one. Your work is justified enough in the praise it recieves. I am looking forward to building your MyRef in the very near future. All the comments by others here grow the desire even more.

SOP - Once again very pretty & happy to hear the hums have been sorted. It can be an ordeal trying to solve that sort of thing. I just wanted to check one item. The earth (yellow / green) comming from the wall socket, is it now still connected to the chassis? In terms of safety it "should" be.

Edit - I like the "M" gesture. Think it wil go on my amp as well when time comes
 
Byrd said:
"and no-one is wrong"

The only people who are wrong are those that cannot carry out a conversation without flinging personal attacks insults and the like around. That is detestable.

I understand your feeling but let me make a little rewind.
Since Mauro registered in diyaudio he has been attacking me. He was registered a few days and he was already on my thread allucinating that I am taken as a 'god' (??!!!), that the snubber is BS, that it's all a question incompetent PCB design.:clown:
He doesn't know me, I don't know how can he allucinate on what I know or what.
I just reveal what I want, nothing more.
His attitude with me since day one is no different from others: they get really MAD with me because they don't understand what's this all about.

Another beauty of a personal attack.
Subtle.
Fresh, today:

mauropenasa said:
I hope only that anyone has built the circuit is satisfied.

I say the same for my circuits.

mauropenasa said:
The technical debates, with non experienced persons, not are of interest me.

:clown:
 
Carlos

I don't really want to get in to a long drawn out debate on this. If you feel my comment applies to Mauro equally then that is your view, however I have done a bit of searching and could find no personal attacks against you as such. Disagreement on your technique, or even people saying that your technique does not work in a particular situation is not a personal attack. Perhaps you are misinterpreting people's comments

What I have found were comments that you have made such as

"Now all, back to your diode "hallucinations"........................."

"You guys are messing things up"

"Russ arms himself as a wise guy, but in reality he knows NOTHING. Anyway, ask him, he says it's a very well known technique, blah blah blah... diodes. "

to quote but a few are either overly aggressive or insulting and it is certainly not a mature reponse. It is likely that members will begin to have less respect for your technical posts if you continue along this vein and that would be a pity as you certainly have made a contribution to this community

Please lets put an end to this :cool:
 
Hi all:
Creditable to all for the thankfulness...

Any precise statements:

My_ref revA to revC is a completely "free" project for the DIYs.

I have given the project to all the DIYs, complete of technical description and PCB layout.
Russ and Plovati have received my original files and my consent to build Kits and PCB, to DIYs use, and I don't receive remuneration of any kind from this materials exchanges.
This persons (and other) have asked my consent because they is serious persons, and cognizant of the originality of my work, and I thank they for the "diffusion" work that do...

The polemics instigated on this circuit by a little group of detractors has convinced me to not behaviour other "diffusion" operations, with new circuits.
My_ref will continue to live for a long time.... ;)


Technical matter:

My_ref is a low price circuit, and a lot of solutions that I have chosen it's "primitive" but effective.
My_ref has not (diode) oscillations on PSU.
My_ref not doesn't need snubber on the DC path.
This say it I, this says it my tools. (see next graph...)

Carlos matter;
I am tired of the personal aggressions of Carlos on the fears snubber and not only.
I have clarified MUCH, MUCH times my "technique" position and only TECHNICAL in his comparisons.
I have sustained much talked and have published a lot of test on the snubber fears, and I am capable of trying my affirmations with concrete measures and simulations.
If Carlos wants show that am not right, is clear of introduce to his concrete and objective evidences , found on calculate, measures and simulations, and I am pleased about counter on a technical plan, as have done with Peranders...

Carlos, you say I have offended you, and I have said much times that I DON'T WANT OFFEND YOU.
DOESN'T provoke me.
If I decides to offend you indeed, I am capable of do it even, but this not produces benefit for this forum.

Please, doesn't misuse of the seriousness of your interlocutors. To the TRUE "gentlemen" the sentence...

Mauro
 
The "real" my_ref prototipe diode (AC) response FFT.

Probe like "Josef_K diode test" (2K-10nF AC probe).

Trafo: Talema 230/25+25V 225VA toroidal

The LC "Tank" (L trafo C= C5+C22 = 100nF) Generate a little Peak at 30Khz,but filter and "shaping" the HF diode spikes, and create a low pass filter over 30Khz.
NO HF overshot, (like various snubber doc. expained....)
 

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And a MY_ref prototipe DC (+35V) FFT.

The spectra it's a classical "charge ramp" FFT distribuction. The graph over 6Khz it's "noise free" too low of -100dB...

HF noise free...
No audio band "diode" noise...
No Full band "diode" noise (verified, not exposed on graph, but evident of IMD Graph free....)

Question:
where are the "spikes" that snubber has to filter ?

Where are the HF oscillations?

Where is the noise, to filter with regulators and various "snubber" net?

Please, Leave behaviour the work of layout PCB and the sizing of the PSU to anyone knows it....

Mauro
 

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One last thing:
I think I own an explanation to Brian, and also maf_au.

I did receive an offer from Brian, we wanted to send me a PCB. maf_au just did that too.
Someone else (by PM) offered to send me a completely assembled Rev. A amp for me to try and send back.
I declined all this.
Why?
I could accept everything and make some more amps, wouldn't I?
But I don't think it's correct, and the reason is: would you all accept my honest oppinion about the amp, for the good or for the worse?
And if I would make some changes and report back, would you accept?
I'm not willing to do that, anyway.
So, these offers, although I thank to those who did, would generate more discussions and trouble than what they are worth.
And I don't have the time and patience for all that.

As for reports, everybody has them, and I have them too.
Here's someone that dared to build an amp following my schematics (amp and psu):

http://www.diyaudio.com/forums/showthread.php?postid=700574#post700574

http://www.diyaudio.com/forums/showthread.php?postid=704406#post704406

There's much more, including the only person that I know that dared to build my AD815 preamp. His reports are so enthusiastic it's contagious, but that's on my PM.

You follow your discussions in a creative way, and good luck.
 
It's a good idea to keep both but if it means waiting longer before they ship I'd source them myself.

Okay honestly, I probably wouldn't bother trying Rev A unless I wasn't entirely happy with Rev C for whatever reason. And if it's so few parts could easily source them myself.

What's the verdict on which version is more musical?

;)
 
chassis

Hello all

Just started the case work for the rev. c amp. Material is 1/8" aluminum; this one will have wood front and back; heatsinks are recycled motorolla mobile radio; will be attached to the metal insides for thermal transfer.Top and sides are rotary sanded; thinking of finishing in clear lacquer.Size is 11-1/2" wide, 13" deep, 4-1/2" high; on-off switch and power chord socket will come from a comp. power supply; fuses to be inside for rails and main power.And maybe my blue l.e.d. fan mounted underneath.

cheers
doggy
 

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