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Old 11th December 2005, 10:35 PM   #91
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Quote:
Originally posted by BrianDonegan
I was speaking more of his general comments regarding critisism of the design.
I didn't see real criticisms of the design, that's on your head, as well as Mauro's.
What I saw was people suggesting improvements, or putting their hands on it and making it theirselves. That's what Rudi did, and I don't see any problem about it.
Think about it, if people make changes and go to that trouble is because they see the amp as promising, or as a good basis for a good amp.
I don't see what's wrong with that.
I think Mauro takes things too personally.
Mauro, if you're reading this, come on, let people build your amp, improve it, whatever. It will always be your amp.
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Old 11th December 2005, 11:01 PM   #92
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Ah. I don't mean critisism as a negative term. I mean it as design comments. Like literary critisism. As in suggested changes and improvements.

Once again, I think we are agreeing, but don't know it.
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Old 11th December 2005, 11:58 PM   #93
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Quote:
Originally posted by carlosfm
Mauro, if you're reading this, come on, let people build your amp, improve it, whatever. It will always be your amp.
I don't think Mauro has any issues with any of that. Its just that if you are going to claim an improvement, it should be with a healthy dose of realism and respect.

Just and when someone claimed to "improve" your "snubber" and you were offended.
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Old 12th December 2005, 08:04 AM   #94
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I am a newbie to this whole forum, as can be seen from my registered date on the left. I have read the entire thread about the Mauro amp (myself wanting to build it), which is an excrutiatingly (sp?) long thread, and I have also read all of the branch off threads including the TP sections, and now this whole thread (a refreshingly light length so far!)

With that said I honestly (from an outsiders point of view completely) do not understand what all of this is about. Mauro posted a very unique design and many people liked it and built it. He posted it on a Do-It-Yourself website with no confidentiality agreement or anything like that (patents, etc...). This means, legally, people are free to make modifications, etc to his circuit and post those modifications. Once something is disclosed, it is unfortunately very hard to protect the rights of the one who made it, since it was disclosed in a public forum (i.e. public knowledge). In fact, here in the United States, there is virtually NO protection for public domain ideas (as far as I know). Unfortunate, yes, but good for the DIY crowd, for sure! We wouldnt exist without these rules (other countries vary of course).

That leaves us with only one way to protect it - respect. From all of the posts I have read and all of the threads, I can't think of a single instance of anybody ever disrespecting Mauro or his design or the "compromises" he made in building it (for cost reasons or whatever). In fact, quite the opposite I have seen. People have shown the utmost respect with the design (TP, Rudi, Carlos). They suggested improvements, and sometimes things got a little tense, which it seems was usually out of misunderstanding...

Insults were thrown around a little, but it seems to me like it was all over nothing. In the end we have to all go by what the original designer has to say about it, but lets face facts here, Mauro has admitted to not being the best at English, so when he says things in type, the "magic of the internet" and its inability to convey proper emotions is even worse. I am quite positive from reading Mauro's responses that he never meant to insult anyone or anything, nor is he overly concerned of people modding his designs (as can be seen in the quote Carlos gave from Mauro to Rudi), yet because of his less than ideal English, his sentences do come out as blunt and direct, causing aggression in many of the people on these threads, and that is very understandable, given that its a text conversation. Does he want to keep being recognized for the base design? Of course! And that just all goes back to respect. Which as I said I feel everyone has exhibited, even if at times things got a little heated.

I am new to the DIY audio scene and when I came to this forum I could not wipe the smile off my face. Here after all my searching was a place where I could interact with others who share my interest in the electrical world. I was so happy to join, and so happy once my moderator hold was lifted (after a few posts ). It seemed like a great community for shared works, idea presentation, and helpful advice. But reading threads like these and seeing how things can get blown so far out of proportion makes me sick. It honestly kills some of the vast amount of enthusiasm I had for DIY audio, and makes me wonder whether this is where I want to spend my time learning about it all. And oviously that is what we are all here for.

So, in short, we can all get along just fine with common sense, and as far as I have seen from the 2000 or so posts I've read on this topic, there is a TON of common sense to go around.

Keep up the good work all of you. Mauro for the design, TP for the propagation, Rudi, Carlos, anyone else for the mods. Just be sure to know where it all came from - All of you, on diyaudio.com

Just an outsider's opinion, take it with a grain of salt of course. Sorry for the long post. I hope I came off alright, I mean NO disrespect to anyone. You all know more than I can even imagine and I look up to all of you.
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Old 12th December 2005, 09:21 AM   #95
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Nice post.....

Now, can we posibly keep the rest of this thread for the actual discussion of the x-Calibre Mauro amp.

I still full intend building one, and reporting back!, may not be quickly though due to cost and parts aquiring processes...

So.... ! There are those of us who would like to see the thread go on. Just notice how Rudi is not posting lateley, same as Mauro.

Its just all this arguing and aruing about arguing and whether we have the right to do so etc... this site is not a physcology paper, lets get back to it being hands on, DIY and real.

Rudi, bring it on!
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Old 12th December 2005, 01:09 PM   #96
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Quote:
Originally posted by Russ White
Just and when someone claimed to "improve" your "snubber" and you were offended.
Russ, I was not offended, where did you see that?
What I don't accept is someone that says he can't detect any improvement by using snubbers on his LM3886 amp claiming an 'improvement' of something he doesn't even understand and he doesn't even admit.
And then he uses his own values.
His site has snubbers all over it, he has a link on his footer with incorrect information.
His 'improved' snubber is only on his head, because it's really no improvement, he doesn't understand it to know what he is doing.
He is using snubbers always with the same values, and in different places, even after regulators.

The snubbers had became a disease for him, I have been followed and attacked since the beginning by P-A.
Maybe he has seen some gold mine on this, I don't know. (???!)
Well, he sees $$$$ on everything, and I don't care what he says or what he does.
Whatever.

I simply let him say it say it's an improvement.
Who cares?
Not me.
He is happy that way.
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Old 12th December 2005, 02:32 PM   #97
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Quote:
Originally posted by carlosfm

What I don't accept is someone that says he can't detect any improvement by using snubbers on his LM3886 amp claiming an 'improvement' of something he doesn't even understand and he doesn't even admit.
And then he uses his own values.
His site has snubbers all over it, he has a link on his footer with incorrect information.
His 'improved' snubber is only on his head, because it's really no improvement, he doesn't understand it to know what he is doing.
He is using snubbers always with the same values, and in different places, even after regulators.

The snubbers had became a disease for him, I have been followed and attacked since the beginning by P-A.
Maybe he has seen some gold mine on this, I don't know. (???!)
Well, he sees $$$$ on everything, and I don't care what he says or what he does.
Whatever.

Carlos,

Your statements right there are precisely what I think Mauro was feeling. People who do not really understand the circuit claiming to "eat for lunch" the implementation of someone who does.

BTW I do think your RC network (I wish it had a better name then snubber which is not correct) in the PS does indeed help almost all common NS chipamps. But success is very dependant on the amp design itself, which in the case of the "My Ref" is so much more than the LM3886, and very much different than a standard chipamp. You cannot apply the same rules to it as you could a NIGC and expect simillar results. Just because it uses a LM3886 does not mean all the same factors apply at all. The "snubber" mod is not one which can be universally apply to all topologies, at least not without some alteration. The "Snubber" must change to suite the circuit/trafo/PS to be truly useful. So there is no possible way one single set of snubber values will work universally unless all else is constant. That will never occur.

Carlos, I have always been very keen to listen to you as I know you clearly know what you are talking about. I have a lot of respect for you. It is too bad you don't think the "My Ref" is worth building, as if you tried it I think you would have a very different opinion, and you may be able to provide more detailed insights for those of us who value and respect your talents. And perhaps you could suggest things based on measurements and experience with the real thing, and not just supposition.

I would be more inclined to give your comments more weight if I actually thought you had something at stake. Something like your very own amplifier.

It would be great to see you contribute in a form more substantial than an outsider's words, not that that is not generous of you to post, it is, but I would love to see more.

So, I think you and Mauro feel a lot alike about your respective work. Keep in mind that from what Rudi said Rudi intended to sell the amp, which if he was not respecting the wishes of the amp's creator is not a good thing to do, just as you might feel about your work being improperly used by others. I am sure Rudi and Mauro have mended fences by now, and I am not bothered by Rudi in the least, in fact I think he just simply made a mistake in judgment which has long been forgiven. It really has no impact on me in the least.

I am just another happy DIYer who mods as much (probably much more) as the next guy. For instance I have tried your RC nets ("Snubber") on the "MyREF" long before it was ever suggested by anyone on the threads, but my findings were not (and have never been after trying all sorts of revisions) positive, and so I asked the designer "why did it not sound better, but worse?" then I learned that the LM3886 in the bridge/current pump configuration is quite another beast from a gainclone or an ordinary chipamp, and also learned of the issues of the ringing supply. But, because I respect those who know better than me I treat my findings with the skepticism they deserve as should we all until we are certain our findings are truly valid. So I have not really said "yes the snubber works in this case" or "no it does not" all I can say is "that guy who designed the amp tells me no it does not help, and could hurt" which was born out in my tests as the amp did not sound as good with those mods in place.

So, no acrymony here, no desire to squelch creativity or new ideas. Just an admonition to those with an open mind to use due dilligence in research, and not to buy too much into the latest "fads" or amplifier buzzword. In the end the person responsible for execution is the "Do it Yourselfer" not the designer. So many amps end up something completely other than what the creator created, but who is to say if it is "better" or "worse", really anyone who wants to can report anything they like. People can and do say whatever they like in a public forum. People can build whatever they like, and I will be very happy for them, but don't expect me to buy into a reported mod without a healthy dose of skeptisism - since I know what the amp is capable of in its stock configuation it will be very hard indeed to sell me on any "huge" improvement.

For what it is worth, I have deigned more than a couple amps based on the "My Ref" design using many major and not-so-major design changes.

Here are a few:

1) Active shunt regulators for the bridge PS (much better than the 78xx-79xx regs). Almost no effect I can detect. Which is to say it still sounds ecellent.

2) A single chip LM4780 stereo version of REV A which uses AD8610s and sounds very good indeed. but better? well who is to say? Sure, I like it a lot, but I am not going to say it eats anything for lunch. I may only like it because it is(at least to some degree) the fruit of my labor, so of course I am biased, so I treat my own opinion as just that, an opinion, not fact.

3) Fully discrete amp modules using a bridge board and a power board and seperate PS. This is the most flexible appproach to the amplifier as it allows all sorts of tweaking since it is completely modular. This version I will likely eventually share, but I will work with Mauro and others to perfect it (as if anything is ever perfected) first.

These works I have done largely on my own, but I have gotten a lot of intellectual help from many here on the forum, not the least of which is Mauro himself. So, it should be obvioius to all I am all for "improving" and making the design my own, but I know my own limits, and I measure my words.

Sorry for the very long post, but I just didn't want anyone to think modding the "My Ref" amp is anything new, or that people don't do it or have not been doing it. It has been done from the beginning well before most DIYers could even obtain a PCB. Now at least they have something to play with. BTW it is very easy to mod TP monoblocs, just email me if you want to know how to try something. I will not discourage anyone, but I am not affraid to say "been there, done that" either, because while I have not tried everything I certianly have tried a lot of the mods proposed, and my experiences are sometimes quite different from what a few have reported. That is fine, but it is a fact everyone should consider. The phrase "your milage may vary" is key.

So happy building/modding/listening persue you happiness in the ways that please you best.

Cheers!
Russ
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Old 12th December 2005, 03:05 PM   #98
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1- Mauro and myself did make peace and all I can say he is a true gentleman

2- just to be clear on a matter. My intension was to give 10 boards away for free. I am not into making up kits seeing that I have my own business to run and that is generating more than enough income.

3- all of us have different systems and some better some worse so how do we know what would sound good in another man's system. if you have small speakers, the amp will be limited, and if you have full range you will hear a bit more of what the amp can do.

the amp needs a system that can do 35hz -> up, changes will be more revealing on larger full range speakers than on smaller speakers seeing that the bass affect everything once you add it into the equation.

4-regarding the snubbers, well that is very simple for some it works and they can hear the difference and some don't in the X if added more life..........very simple but in other systems it might detract from the sound. The best is to find the point were you are happy and leave it like that, it most probably not last long before you change something.

5- the X works better in my system than the previous board that I build. And it is now stable without any clipping what so ever. I am getting 56W into 8Ohm. I am actually thinking of asking Mauro how to reduce the gain.


This is a fun project, and if i had to design amps or variations for a living I would have been bankrupt by now. So guys. Lets move on and build some really hot stuff.
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Old 12th December 2005, 03:11 PM   #99
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Quote:
Originally posted by Russ White
BTW I do think your RC network (I wish it had a better name then snubber which is not correct) in the PS does indeed help almost all common NS chipamps. But success is very dependant on the amp design itself, which in the case of the "My Ref" is so much more than the LM3886, and very much different than a standard chipamp. You cannot apply the same rules to it as you could a NIGC and expect simillar results. Just because it uses a LM3886 does not mean all the same factors apply at all. The "snubber" mod is not one which can be universally apply to all topologies, at least not without some alteration. The "Snubber" must change to suite the circuit/trafo/PS to be truly useful. So there is no possible way one single set of snubber values will work universally unless all else is constant. That will never occur.
Russ, just a note on this, because I really don't want to discuss this any longer, it's not worth it.
The amp uses an LM3886 chip, a bipolar power op-amp, with quasi-complimentary output stage.
You can't change the internal circuit, and whatever you do externally, the chip (or the amp) is sensitive to the PSU and it's implementation.
The PSU is in the signal path.
Whatever you can do to improve it, you will also improve the amp.

I'm not saying that it can't be optimized, what I can suggest when asked for is what works for me, consistently.
Whatever trafo or diodes I use, the values I'm using are giving me consistent results.
If I have built this amp I would provide more information, but I would go into all sorts of trouble and discussions, which I'm not willing to.
And as I said, the design doesn't appeal to me, and the reasons why would again generate discussion, so I better be quiet as I have been. If nobody bothers me I won't bother anyone.
Everyone is free to build the amp he/she wants, so enjoy.

PS: snubber is one of the correct ways of calling that RC network, I have provided that info.
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Old 12th December 2005, 06:41 PM   #100
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Quote:
Mauro and myself did make peace and all I can say he is a true gentleman
Rudi, I am glad to hear that!

Someone mentioned that this is a much more expensive version of the original Rev. C due to the "hotrodding". Could someone give me an estimate at how much it would cost to stuff the board? The Rev. C originally costs around 95 bucks to stuff (kit from TP) but includes the boards themselves.

I was going to etch the board myself, as the PDF rudi posted is so perfect as far as contrast and lines. But I would like to know why on the copper PDF is their two boards, and they are identical as far as I can see... Is there a reason? Am I missing a difference? Or is it for convenience for stereo use?

And one last question, if I etched this board of Rudi's would I be able to stuff it with original Rev. C parts if I so chose? Just out of curiosity since I have lots of the parts for the original laying around.

Thanks,

Ron
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