My "audiophile" LM3886 approach

Well I always thought the sound of the LM3886 were OK, nothing to get excited about, snubbers did improve it. But only just (I generally call this micro tweaking). With Mauro's design I certainly experienced a huge improvement. And at some stage I even wanted to use it as my ref amp (that didn't last long seeing that I still prefer the JLH)

I recently completed my tripath TK2350 and all I can say is that it outperform anything else.

I encourage people to mess with the current design because improvements are always welcome. I am currently working on something that might be interesting to some of you and I will share it as soon as I have completed the build and done some listing.
 
basis for my new experiment

Here is the new boards for my Ref C. as usual I like to use the dual bridge rectifiers.

But as bonus in the name of "experimentation" and to evoke comments I would like to add the following finding from NAIM. For the next finding to be true you need two bridge rectifiers per channel.

Naim found that if you swap the phase of the one secondary in relation to the other then you get a much better bass note. (Why this is I do not know) but I am going to try it on these little amps. Now it could be true that the change is significantly more noticeable when you use two bridges feeding a stereo pair. (As I have done with my Tripath, normally thin in the bass region, but now it is phenomenal deeper and tighter than any other amp I have listened to)

The other option that I have with my configuration is to use a trafo secondary per rail (one trafo supply just possitive and one just negative.). In effect giving each rail its own transformer.

just some food for thought

Rudi
 

Attachments

  • ref-2.jpg
    ref-2.jpg
    43 KB · Views: 1,423
Hi all,
I am embittered by the polemics that have read.
Not don't want speak of the matters (PSU, diodes, snubber), because this forum is not proper, and because I have already expressed my thought.
The only thing that wants underline to anyone reads this thread is the consideration that much DIYs ( not only Carlos and not only on this matters ) have for the planners of audio circuits.
It seems me much "strange" that I am appreciated to have planed a circuit as My_ref, but that my indications on the PCBlayout and PSU are considered "non reliables". ( "- OK, Mauro has given a beautiful circuit, don't know the exact reasons of this quality, but I praies work and improve it...-").
I see an excessive "anxiety" of change of the circuits.
I want remember that before My_Ref, any has published never circuits to chips amp with this characteristics and this configuration, and it is spoken only of little variations to the National datasheet.
If some person feel the need of amelioration, is able develop a complete circuit diverged with better performances.
Gives more weigh to the change that to the project is simply offensive.
It is discounted that my next projects will follow a different road...

I don't accept lessons on " think with the really head ".
There are 2 things that serve to do it:

1 have a head
2 have competence.

Is not enough to think, be necessary know, first...

Ciao

Mauro
 
Hi Mauro.

I do not think you need to worry. you have prooved that you design is superior to any other chipamp configuration with or with out the old snubber ( i have even found that your amp sounds good with cheap components, that is the real proof of a good design)

there is none as deaf as those that doesn't want to hear
 
mauropenasa said:
I don't accept lessons on " think with the really head ".
There are 2 things that serve to do it:

1 have a head
2 have competence.

Is not enough to think, be necessary know, first...

Ciao

Mauro
Click to expand...


Hi Mauro,

I think you didn't understand my post and what happened here. Nobody accused YOU by not thinking with your head.
You and Russ deturp the reality in your convenience.
What's wrong with someone that has built your amp to insert a couple of additional parts and make a test?
If that's forbidden, you better print it on the PCB.
I have never talked about the snubbers on your thread (some others did), but you can't avoid that someone that builds your circuit would go on and try it.
What I did not like was the reception that this member had just by reporting improvements.
And I also don't like to see the tone of your comments about the snubbers, even if you are against it.
I never made jokes about your amp, did I?
Well, somebody pushed me off yesterday and I had to make some remarks.
I'm very sad that it turned out the way it did. Even after saying that I had good intentions, that you guys didn't take me wrong, right on my first post.
But even then, the reaction was like I wanted to make some harm or that I was saying the amp is not good, etc.
You guys have a very strong immagination, or some ill sindrome.

End of the story.
 
carlosfm said:

Nobody accused YOU by not thinking with your head.
Click to expand...

Well lets get it clear then - who were you saying was not thinking with their head. It must be somebody? It seems to me you must have some severe reading / writing impediments

End of story!
 
Byrd said:


Well lets get it clear then - who were you saying was not thinking with their head. It must be somebody? It seems to me you must have some severe reading / writing impediments

End of story!
Click to expand...

I only told Gary that he though with his head in a way to improve, he took the initiative to experiment.
Nobody told him to do so.
That's what I meant.
But I have aready explained this, didn't I??!
 
So you were also saying that others were thinking with their heads?

By simple logic it must be one way or the other.

In the context of the earlier conversation your implied meaning was that the others that were providing suggestions as to why Gary noticed an improvement (other than the snubber), were not thinking with their heads. That they were simply being "sheep". That is how I read it anyway as I am sure others did as well.

Is it your view that a "snuberized amp" is ALWAYS better than unsnubberised? If so have you consulted with Levinson, Rowland et al about purchasing rights to your amazing design - that you designed from scratch?
 
Guys

Due to some misinterpretations and misunderstandings this is slowly turning in one of "THOSE" threads which doesn't benefit the actual topic at all. Leave it like it is and get on with the project please. There's already enough fighting going on in this world.

Best regards
 
I think this all comes down to tone* (hard to express tone in text like this) and history. Let's let bygones be bygones and continue playing and having fun.

* I often say things in email/IM/forums that can be interpreted differently depending on the reader's mood. Without vocal inflection and the like, it is easy for misunderstandings to occur. I suggest this is all that has happened here. I think we all want to get along, so let's just get on with it.


Tips for good living, canbe used as tips for good posting:

1. Take into account that great love and great achievements involve great risk.

2. When you lose, don't lose the lesson.

3. Follow the three Rs: Respect for self, respect for others, responsibility for all your actions.

4. Remember that not getting what you want is sometimes a wonderful stroke of luck.

5. Learn the rules so you know how to break them properly.

6. Don't let a little dispute injure a great friendship.

7. When you realize you've made a mistake, take immediate steps to correct it.

8. Spend some time alone every day.

9. Open your arms to change, but don't let go of your values.

10. Remember that silence is sometimes the best answer.

11. Live a good, honorable life. Then when you get older and think back, you'll be able to enjoy it a second time.

12. A loving atmosphere in your home is the foundation for your life.

13. In disagreements with loved ones, deal only with the current situation. Don't bring up the past.

14. Share your knowledge. It's a way to achieve immortality.

15. Be gentle with the earth.

16. Once a year, go someplace you've never been before.

17. Remember that the best relationship is one in which your love for each other exceeds your need for each other.

18. Judge your success by what you had to give up in order to get it.

19. Approach love and cooking with reckless abandon.
 
Byrd said:
So you were also saying that others were thinking with their heads?

By simple logic it must be one way or the other.

In the context of the earlier conversation your implied meaning was that the others that were providing suggestions as to why Gary noticed an improvement (other than the snubber), were not thinking with their heads. That they were simply being "sheep". That is how I read it anyway as I am sure others did as well.

Is it your view that a "snuberized amp" is ALWAYS better than unsnubberised? If so have you consulted with Levinson, Rowland et al about purchasing rights to your amazing design - that you designed from scratch?
Click to expand...

Really, I'm trying to end this but you keep allucinating.

Here's a couple of pages about black magic.
Read this:

http://www.diyaudio.com/forums/showthread.php?postid=547988#post547988
 
Hi Carlos,
I don't understand your outlet over my words.
I have only explained my philosophy and my perplexity, and is not gone into the single matters.

From a great deal of time I feel "subjective" discourses , correct and wrong.
My_ref shows that the quality of the sound depends much more from the quality of the circuit ( and from the layout PCB ) that from the individuals component (active and passive).
I have shown this things with reporting techniques, study and measures (and a concrete project).

If some believe of be offended by my theories, is not guilt mine...

Ciao

Mauro
 
mauropenasa said:
If some believe of be offended by my theories, is not guilt mine...
Click to expand...

I like that, because I feel the same. 😎

PS: I agree with you on the PCB layout, it is VERY important.
But I also believe that, with this taken care of, the PSU has a big influence in ANY amplifier.
I don't use 'gold-plated' passive components, either.
 
I am very new to this forum and and have read a lot of this thread in the last 2 days. I have built the lm3875 lm4780 brian gt kits.I can see a lot of effort has gone into the design and construction of this new amp; my hat is off to the designer and those who have implemented the design.

Would it be possible to get the pcb for a stereo config.and be directed to a parts list? I just got a Hakko 936 soldering station and would like to make this amp.

yes I like to eat at table also!🙂
 

Attachments

  • planer 037 (custom).jpg
    planer 037 (custom).jpg
    28.1 KB · Views: 1,327
Hi Doggy, I made a batch or the stereo boards a while back, but they are long gone. Still, I plan on ordering some more soon, so stay tuned. The good news is that you could build a dual monoblocs version with one trafo instead, and you would be able to do that very soon, as I am ordering the PCBs for that today. 🙂

Brian and I will post more info on the kits/PCBs very soon.

Cheers!
Russ
 
You must log in or register to reply here.
Back
Top