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Review and Measurements of Purifi 1ET400A Amplifier

March Audio

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Michel Davis (bavmike, Mivera Audio) made a interesting picture of the new module, where I can see the Rubycon electrolytics and the bottom metal part.

https://i.pinimg.com/originals/b3/77/00/b37700d1f0a53de706583f50e1848547.jpg

Optimized and reduced.

View attachment 30174


And the rear side of the input buffer with the OPA1612.

View attachment 30175

With how tiny it is to desolder two SMD resistors and weld other equivalents of 0.1% or 0.01% tolerance to increase the CMRR must be a fine job. A good magnifying glass would help :cool:


Oh dear Maty is off again.....

That is not the input buffer.
 

March Audio

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To be honest I do understand what you are trying to tell me/us? The Purifi supports custom input buffers, the input board supplied is mainly for evaluation and testing purposes (as one can tell by the layout and speaker connectors used). Literally everything except for the main amp pcb can be adjusted to the OEMs/DIYers preferences?!

If a third party supplier decides to offer a custom input buffer board for purchase (as I am sure someone will), they can go ahead and use 0,01% resistors where it matters .
This.
 

maty

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From a Big picture made by Mivera Audio:

https://i.pinimg.com/originals/37/95/07/379507a819a7e50fd3cf4659123d1d18.jpg

Updated: change from PNG (940 Kb) to JPG (235 Kb)

Purifi-1ET400A-connector-board-cut.jpg


The famous OPA1612A and some SMD components:

Purifi-1ET400A-connector-board-OPA1612A.jpg
 
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Matias

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I see potential for modding. :p
 

Matias

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Maty, I have nothing fancy in mind, just removing the opamps of the I/O board and installing a DIP8 socket in its place for some opamp rolling fun.

Maybe your idea of improving resistors to higher tolerance parts?

Also not a mod but more of an extension would be a DAC board with mounted XLRs to plug into the center part of the I/O board? That would be an awkward fit with the speaker cables on the sides. :)
 

maty

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Yes, a DIY input board with the best specs and measurements to force boutique buffers sellers to advertise measurements of their expensive products. Optimized for different op-amps, facilitating the change of the sound profile, as example: predominant H2 with different values and H3 at least 10 or 15 dB less, and no others harmonics.

Moreover, to allow two profiles, the previous one and another very clean and that could be selected from a switch in the rear. It would be a winning product.
 

Xulonn

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pirad

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Changing the "sound profile" with physical rolling of opamps is so oldschool...
Give me an input board that offers DEQX's capabilities and add Dirac, Atmos, VST/AudioUnits ...
Finish off with a bufferless DAC.
 

maty

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What you say should be done by companies as a lucrative business. The above, the design of the DIY PCB, buying group and component list should be the first I think. Cheap and easy.

The same op-amp with two implementations in the same board -> two sound profiles with an external switch.
 
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allhifi

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We love personal experiences. It is just that we want that to relate only to what the ear received, not what the brain manufactured after the fact (i.e. tests need to have controls). Without this, subjective experiences are so wrong and so routinely so, that it is not worth sharing it with us. We know people can perceive the impossible. So let's not keep telling us that you "heard" that when you can't show that is what was actually heard.

In this forum, we rather stick to what we can prove, not imagine to be so.

amirm: It will continue to be an uninspiring/weak website/blog when that is your guiding principle/reasoning.

Did it ever occur to you (and followers) that perhaps the listening experience is (far) more than what "our
ears hear" ? Such as what was 'felt' (naturally through hearing) and the great depth of clarity, texture
and dimensionality presented by via Amp 'A', but not Amp ''B'.

And you wish for the listener and/or manufacturer to give you a'specification' for this type (of routine)
interpretation made by music lover's/hi-fi buffs the world over ? Yet, no matter the sensibility of the
argument, some will never be able to see/feel/hear what others do.

Additionally, those that appreciate premium, nuanced, articulate sound reproduction (better hi-fi) are
comfortable in the knowledge of their SQ interpretations and feel not threatened there may not be a
readily identifiable 'measurement' to "prove" it .

peter jasz
 
D

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amirm: It will continue to be an uninspiring/weak website/blog when that is your guiding principle/reasoning.

Did it ever occur to you (and followers) that perhaps the listening experience is (far) more than what "our
ears hear" ? Such as what was 'felt' (naturally through hearing) and the great depth of clarity, texture
and dimensionality presented by via Amp 'A', but not Amp ''B'.

And you wish for the listener and/or manufacturer to give you a'specification' for this type (of routine)
interpretation made by music lover's/hi-fi buffs the world over ? Yet, no matter the sensibility of the
argument, some will never be able to see/feel/hear what others do.

Additionally, those that appreciate premium, nuanced, articulate sound reproduction (better hi-fi) are
comfortable in the knowledge of their SQ interpretations and feel not threatened there may not be a
readily identifiable 'measurement' to "prove" it .

peter jasz
That's one of the best strawman arguments I've seen in a long time.

Dave.
 

Xulonn

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That's one of the best strawman arguments I've seen in a long time.

It will continue to be an uninspiring/weak website/blog when that is your guiding principle/reasoning.

Subjective-only audiophiles really get whiny and defensive when their beliefs are challenged - notice the above attempt at a put-down of ASR - truly lame! The person also appears to not even know what an "internet forum website" is compared to a blog.

Life is much more fun when one can acknowledge scientific reality, and still enjoy subjective pleasures - a combination of traits that I believe I share with many members here.

As another member here posted, this says a lot about the subject poster: LINK
 
OP
amirm

amirm

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amirm: It will continue to be an uninspiring/weak website/blog when that is your guiding principle/reasoning.

Did it ever occur to you (and followers) that perhaps the listening experience is (far) more than what "our
ears hear" ? Such as what was 'felt' (naturally through hearing) and the great depth of clarity, texture
and dimensionality presented by via Amp 'A', but not Amp ''B'.

And you wish for the listener and/or manufacturer to give you a'specification' for this type (of routine)
interpretation made by music lover's/hi-fi buffs the world over ? Yet, no matter the sensibility of the
argument, some will never be able to see/feel/hear what others do.
Let me tell you a little secret: it is the music itself that brings joy and emotion to life. That is what you are supposed to feel.

Additionally, those that appreciate premium, nuanced, articulate sound reproduction (better hi-fi) are
comfortable in the knowledge of their SQ interpretations and feel not threatened there may not be a
readily identifiable 'measurement' to "prove" it .

peter jasz
Well you are not comfortable because you seek validation of your improper audio evaluations from us.

Really, the audience you represent seem to always be in pain thinking any and all things impact their sound. They chase every wrong road instead of just sitting back and enjoy music through an excellently designed system like we do ...
 
OP
amirm

amirm

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amirm: It will continue to be an uninspiring/weak website/blog when that is your guiding principle/reasoning.
Well, your data there, as your statements about audio are fortunately incorrect. Here is our public trend for the last 90 days:

1564443316286.png


There are 30 million active websites in the world. We are better than 29.9 million of them! We are only a couple of years old. Hopefully the support of the membership and visitors alike continue for transparency and objectivity in audio. Heaven knows enough bits have been wasted on unreliable ideas and assumptions about audio online....
 
OP
amirm

amirm

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Did you ask Alexa to get the Alexa rank for ASR?
No, we broke up a few months ago and she doesn't want to talk to me anymore. I had to go to the website to get that data....
 

restorer-john

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No, we broke up a few months ago and she doesn't want to talk to me anymore

She obviously found out you were also seeing Siri and Cortana on the side...you're such a player, Amir.
 
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