Changing amps
I should have time soon to build some amps. The X-Caliber looks very nice. If I tried to compare to the latest CFM NIGC, both should have LM3886 I guess.
OT, but are there any circuit changes needed to use the LM3875 in the latest CFM NIGC? I have a bunch and only one pair of 3886 right now.
I have a pefectly working My_Ref C. It will be interesting to hear it compared to either of these two amps. But my power demands are very low, less than 1 watt at peaks.
George
I should have time soon to build some amps. The X-Caliber looks very nice. If I tried to compare to the latest CFM NIGC, both should have LM3886 I guess.
OT, but are there any circuit changes needed to use the LM3875 in the latest CFM NIGC? I have a bunch and only one pair of 3886 right now.
I have a pefectly working My_Ref C. It will be interesting to hear it compared to either of these two amps. But my power demands are very low, less than 1 watt at peaks.
George
rudi said:
Rudi, just look what a power amp with just 1,000uF of PSU capacitance can make for you.
Hash treble is because of the very low filtered PSU and high ripple, and the lower PSRR of the chips at high frequencies.
The rest is the inability of the amp to drive most speakers.
You are on SET territory to match the amp with a pair of speakers.
Re: Re: And the winner is....
WHAT?????.......Jitter, my DAC does not have jitter.
Carlos you just wish you had a DAC like mine.
the Cap is to block 90v DC. and also determines the LF rolloff. so nothing to do with staging and what have you. here you lost it a bit
for the rest. the LM3875 will always suffer, compared to my X-Calibre. the amp is simply the best , Ok maybe I am loosing it a bit.
as far as T.'s comments. I will try the snubber today and maybe incorporate it.
Carlos just as a parting word. you are welcome to rant and rave as much as you like here. we will just sit back and grind at your antics
carlosfm said:
WHAT?????.......Jitter, my DAC does not have jitter.
Carlos you just wish you had a DAC like mine. the Cap is to block 90v DC. and also determines the LF rolloff. so nothing to do with staging and what have you. here you lost it a bit
for the rest. the LM3875 will always suffer, compared to my X-Calibre. the amp is simply the best
, Ok maybe I am loosing it a bit.as far as T.'s comments. I will try the snubber today and maybe incorporate it.
Carlos just as a parting word. you are welcome to rant and rave as much as you like here. we will just sit back and grind at your antics
Attachments
thejohn said:
Unregulated always sound more musical. But you need to get rid of the ripple to get the bass right. So your only option is a follows
HUGE capacitor banks to smooth the power and a HUGE transformer to drive the poor caps. Then you get very good smoothing. Best of both worlds and the end result is deep clean bass.
That is why I went for 20 000uf per rail 40000uf per channel and 1.1kva transformers and the end result is very evident when you listen to it
I have been playing a bit with the amp this afternoon and I discovered a that only the guys that bought the TP version know about the change of resistor values.
R41 and 42 should be 47R instead of 270R, this makes the amp more stable and takes care of the harsh clipping. This was never indicated on the schematics.
I remember somebody asking about it on the original thread.
Seems that the Ref A will be much more stable according to a simulation. I will test the Ref-A version on the X-Calibre and let you know
R41 and 42 should be 47R instead of 270R, this makes the amp more stable and takes care of the harsh clipping. This was never indicated on the schematics.
I remember somebody asking about it on the original thread.
Seems that the Ref A will be much more stable according to a simulation. I will test the Ref-A version on the X-Calibre and let you know
Re: Re: Re: And the winner is....
No, it does not mean that.
I just post the unregulated PSU because it's easier for you to build.
Wow, that's a hell of a claim.
Rudi, that is not possible, don't believe that marketing BS.
Whatever interface you use, NO JITTER is not possible in digital audio.
How do you know???!!!
I don't wish anything.
What staging???
You're lost, you didn't understand what I said at all.
It's exactly the LF rolloff point that I meant.
With a 1uF output cap, you'll have a high-pass filfer at ~16Hz if you use a 10k volume pot after it, a little on the high side, don't you think?
If you need this to have tighter bass, something else is wrong, you should not need to cut this high.
That's what I meant, take it constructively, and try to improve that.
Please.
Rudi, you're making another claim as absolute, and it's not.
How can you say always?
I don't agree that you need those 1.1kva trafos.
And there's more than 'deep clean bass'. More capacitance is better, and a CRC arrangement still brings improvements. You'll hear clean highs to cry for the cleaner the PSU you use, and low impedance up to very high frequencies.
The regulated PSU I use also provides very 'musical' results (if you want to be subjective to the extreme), ultra-tight and deep bass, gorgeously clean mids and treble. And this with a smaller trafo and lower capacitance.
Please don't make abstract or generic claims, and you also don't have to believe what I say.
You just need to build both and try for yourself.
thejohn said:
No, it does not mean that.
I just post the unregulated PSU because it's easier for you to build.
rudi said:WHAT?????.......Jitter, my DAC does not have jitter.
Wow, that's a hell of a claim.
Rudi, that is not possible, don't believe that marketing BS.
Whatever interface you use, NO JITTER is not possible in digital audio.
rudi said:Carlos you just wish you had a DAC like mine.
How do you know???!!!
I don't wish anything.
rudi said:the Cap is to block 90v DC. and also determines the LF rolloff. so nothing to do with staging and what have you. here you lost it a bit
What staging???
You're lost, you didn't understand what I said at all.
It's exactly the LF rolloff point that I meant.
With a 1uF output cap, you'll have a high-pass filfer at ~16Hz if you use a 10k volume pot after it, a little on the high side, don't you think?
If you need this to have tighter bass, something else is wrong, you should not need to cut this high.
That's what I meant, take it constructively, and try to improve that.
Please.
rudi said:
Rudi, you're making another claim as absolute, and it's not.
How can you say always?
rudi said:
I don't agree that you need those 1.1kva trafos.
And there's more than 'deep clean bass'. More capacitance is better, and a CRC arrangement still brings improvements. You'll hear clean highs to cry for the cleaner the PSU you use, and low impedance up to very high frequencies.
The regulated PSU I use also provides very 'musical' results (if you want to be subjective to the extreme), ultra-tight and deep bass, gorgeously clean mids and treble. And this with a smaller trafo and lower capacitance.
Please don't make abstract or generic claims, and you also don't have to believe what I say.
You just need to build both and try for yourself.
pcb
Hi Rudi,greetings
When you can,please let me know about getting 2 pcb's for a stereo pair and also those sprague p.s. caps. I would like to build this version of the Mauro p. amp also. Put me on your list.
I am still learning,and want a good power supply.
I wonder has anyone compared the mur860 diodes to a composite 25 amp rectifier bridge?
Cheers
Doggy
Hi Rudi,greetings
When you can,please let me know about getting 2 pcb's for a stereo pair and also those sprague p.s. caps. I would like to build this version of the Mauro p. amp also. Put me on your list.
I am still learning,and want a good power supply.
I wonder has anyone compared the mur860 diodes to a composite 25 amp rectifier bridge?
Cheers
Doggy
rudi said:Hey Carlos
exactly the ranting and raving i was talking about. at least you add flavour to everything
You tried the snubber, right?
You liked it, right?
Mmmm... maybe I'm not so lunatic as some may think.
Why did I say that this amp needed snubbers on those big caps?
Did I even needed to build it and try it?
No.
Why? Because I've been there, done that.
Do you believe me?
Whatever.
carlosfm said:
You tried the snubber, right?
You liked it, right?
Mmmm... maybe I'm not so lunatic as some may think.
Whatever.
Wait, which amp are we talking about here, Rudi's new 'version' or the original revisions? There were mixed results with the original if memory serves. Yeah I know, try it before commenting, so I'm not commenting on whether it enhances anything, just which version of the amp we're talking about.
Carlos, even if your deemed a lunatic no one can take your passion away so you'd be a passionate lunatic
Cheers
Kendal
Member
Joined 2003
I don't really understand all this talk about whether the subber should be there or not. Everyone has their own tastes, and the parts for the snubber aren't expensive or anything so what's the harm in trying it out and listening for yourself and deciding what you like best. I don't believe there is any right or wrong here, just personal preference. Why should we as a group have to come to a conclusion of what is better. It's your amp, do what you like with it.
Good work on your X-calibre amplifier Rudi. I really like the idea of a regulated supply for the op-amps. I see you've gone with a single relay for each channel. Is there any reason to do this instead of a double pole relay (is that the right term)? Or was it just easier to design the PCB this way?
Good work on your X-calibre amplifier Rudi. I really like the idea of a regulated supply for the op-amps. I see you've gone with a single relay for each channel. Is there any reason to do this instead of a double pole relay (is that the right term)? Or was it just easier to design the PCB this way?
lazyfly said:
I'm talking about my experience with these chips, I've done and tested many things with them.
lazyfly said:
Nobody tested my last PSUs with this amp. It would not be practical, anyway.
lazyfly said:Carlos, even if your deemed a lunatic no one can take your passion away so you'd be a passionate lunatic
Ok, then.
Well there seems to be sour grapes in the twisted pear camp.
Well let’s put some explanations and some apologies were it is due
1. Mauro. Not for one moment did I claim the amp design as my own. I have always given you credit for the schematic and the ingenious thought of implementation. And I thank you for you that
2. Hot Roding is a term to personalize something to your own tastes. In most case upping power or performance. In this case making a different power supply stage
3. My reference to this being commercial. From the beginning Russ stated that they are not doing it for a profit. I own my own business and not for one moment did the math indicate a profit. The point I am trying to make is that there only seem to be help to the people that build the TP version and it is ONLY about the TP version and if there is a small variation there were no support for this.
4. The X-Calibre is my development just as the current TP Ref C is a Russ White development, (by the sound of it with help from Mauro.), But I did mention that it is done according to Mauro design. Again giving him credit for the Amp part of the design.
5. There have been a lot of questions regarding the tweaking of this amp and I just wanted to satisfy the curiosity, and it actually worked. And it works extremely well.
6. The amp that I have originally implemented does clip, I started of by just mentioning it and there were no help to solve the problem or just a speculation of possible problem. If it were a TP board there would have been A LOT defence and immediate help. So the question is why does it clip so harshly when it gets to its limits. The reality is that I have a 9m x 6.5m x 3.2m listening room. It takes a lot of power to fill that room. And the ref-c is most probably not the amp to fill this space. I am already looking a locally amp that will give me 250w and can drive to 1.2 ohm, so no fear in me pursuing this variation, I will keep it strictly DIY. Just as a matter of interest. I tested the X last night and it got to 56W at 8ohm, then it became totally unstable, not just the normal clipping, I did not test it into 4 ohm
To bring me to the public apology.
Guys I am very sorry that I have pushed Mauro over the edge and robbed you of your new amp project.
I am sorry if I have offended anybody with any of my wild statement. I is my personality to get people to take initiative and to push them a bit
I am sorry if I took a condemning tone. It was uncalled for.
The TP is most probably a fantastic amp and I have never compared it to a X so to say that it will eat if for breakfast is very unfair. But it has been done in innocent competitive spirit.
Lets face the facts.
Musical fidelity came up with the topology. Then Mauro adapted it and implemented a more technical version by removing the mosfets and replacing them with a Lm3886 and documenting it in a fantastic way, I took that again and just implemented some known practices on the power supply.
Well let’s put some explanations and some apologies were it is due
1. Mauro. Not for one moment did I claim the amp design as my own. I have always given you credit for the schematic and the ingenious thought of implementation. And I thank you for you that
2. Hot Roding is a term to personalize something to your own tastes. In most case upping power or performance. In this case making a different power supply stage
3. My reference to this being commercial. From the beginning Russ stated that they are not doing it for a profit. I own my own business and not for one moment did the math indicate a profit. The point I am trying to make is that there only seem to be help to the people that build the TP version and it is ONLY about the TP version and if there is a small variation there were no support for this.
4. The X-Calibre is my development just as the current TP Ref C is a Russ White development, (by the sound of it with help from Mauro.), But I did mention that it is done according to Mauro design. Again giving him credit for the Amp part of the design.
5. There have been a lot of questions regarding the tweaking of this amp and I just wanted to satisfy the curiosity, and it actually worked. And it works extremely well.
6. The amp that I have originally implemented does clip, I started of by just mentioning it and there were no help to solve the problem or just a speculation of possible problem. If it were a TP board there would have been A LOT defence and immediate help. So the question is why does it clip so harshly when it gets to its limits. The reality is that I have a 9m x 6.5m x 3.2m listening room. It takes a lot of power to fill that room. And the ref-c is most probably not the amp to fill this space. I am already looking a locally amp that will give me 250w and can drive to 1.2 ohm, so no fear in me pursuing this variation, I will keep it strictly DIY. Just as a matter of interest. I tested the X last night and it got to 56W at 8ohm, then it became totally unstable, not just the normal clipping, I did not test it into 4 ohm
To bring me to the public apology.
Guys I am very sorry that I have pushed Mauro over the edge and robbed you of your new amp project.
I am sorry if I have offended anybody with any of my wild statement. I is my personality to get people to take initiative and to push them a bit
I am sorry if I took a condemning tone. It was uncalled for.
The TP is most probably a fantastic amp and I have never compared it to a X so to say that it will eat if for breakfast is very unfair. But it has been done in innocent competitive spirit.
Lets face the facts.
Musical fidelity came up with the topology. Then Mauro adapted it and implemented a more technical version by removing the mosfets and replacing them with a Lm3886 and documenting it in a fantastic way, I took that again and just implemented some known practices on the power supply.
carlosfm said:
You tried the snubber, right?
You liked it, right?
Mmmm... maybe I'm not so lunatic as some may think.
Why did I say that this amp needed snubbers on those big caps?
Did I even needed to build it and try it?
No.
Why? Because I've been there, done that.
Do you believe me?
Whatever.
Hi Carlos. I have tried them according to your latest supply and it does give it alot more life.
very much worth the little effort that it took to implement
After an unfortunate debate I am withdrawing my efforts from this forum out of respect for the designer. I did not realise that even to post the design i needed his permision
Feel free to contact me directly if you want my view regarding this alternative layout.
My personal opinion is that it sounds extremely good. the layout as is, does work and i have 2 of these running
If anybody would like to make the tweakers board available you have my full permission to do so but please ask Mauro if he has any objections
The Sprague caps that i had available, i will sell wholesale.
Feel free to contact me directly if you want my view regarding this alternative layout.
My personal opinion is that it sounds extremely good. the layout as is, does work and i have 2 of these running
If anybody would like to make the tweakers board available you have my full permission to do so but please ask Mauro if he has any objections
The Sprague caps that i had available, i will sell wholesale.
I for one am disappointed this little development has caused such a ruckus.
Ironically it was Rudi's enthusiasm for Mauro's amp that made me take the plunge - and I'm glad I did.
I hope you can still post your opinions of any mods you make to the basic design - even if they aren't improvements
Ironically it was Rudi's enthusiasm for Mauro's amp that made me take the plunge - and I'm glad I did.
I hope you can still post your opinions of any mods you make to the basic design - even if they aren't improvements
i would just like to say something and that is if i came up with a design and someone else made it better, called it something else and said their modded version of my amp could eat the unmodded version for breakfast i wouldnt take so much offense i would probly build the modded version for having better sound and thank the modder for posting the mods but thats just me
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