Theoretica Applied Physics BACCH


Facetime with Edgar during intro setup!

The BACCH -dSP 13.5 will make you a happier man for certain. I am surprised Edgar revealed his secret. But I will say mounting case and all solves part replacement’s for only a short time given Apple’s continued advancement philosophy.


Replaced the Legos with a second absorber. Huge positive difference. The soundstage came way forward. Since I had two extra mobile absorbers, I played around a lot with putting them here and there, different locations left and right, in the corners, back of the room (where the Legos and my discs are now) etc. Simple mirror left-right covering up more of the wall, whether for nearest or furthest speaker first reflection on each side, seems to make the biggest difference. Sound bounces around in waves, not in laser beam lines.


I am glad it worked out. Ditcjh diffusion ad absorbers on sidewalls works best for BACCH!

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Looks like too many toys…father and son.

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I actually found a new use for HQPlayer with BACCH. I use it either to upscale to 24-192 or to downscale to 24-192 and feed PCM like that into BACCH4Mac. The Mac does not have to think about bitrate then. It is always fed the same. Downscaling is much more calculation intensive than is upscaling. It is not just a matter of dropping every other bit. I can get DSD64 down to 24-192 reliably with no glitches ever. To get DSD128 down to 24-96 was just not going well. But to 24-192 works fine.

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Oh man, I am listening to vinyl through the BACCH and switched to the Phono Preamp right into the preamp. No BACCH Device involved.
Damn, that sounds a lot better and more 3D!!! How could this be.
I’m going to do it some more…


It is interesting. Sometimes I switch back to default, no BACCH filters, and hear a song as I first came to love it with the singer and the instruments closer together… and in a simple line between the speakers… but it can seem suddenly more intimate. Before long, I go back to BACCH tho.

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This is different. This is not using the BACCH-SP at all. Not switching the filter to defeat. Not using the device.

Turntable → Phono Preamp → Preamp → Amp → Speakers.

I am not using the best interconnect between the Phono Preamp and the BACCH-SP. But I can’t use two balanced cables from the Phono Preamp. It has one pair of balanced and one pair of unbalanced. I need to find a pair of Stealth Sakra V17 LE unbalanced cables to do the test proper.

I believe my Gryphon gear is a much higher standard than the BACCH-SP is. I am really looking forward to the upgrade!!


To be honest, this was my first experience with the BACCH…impressing in its own effect but clearly worse in the grade of general quality a non digitized or even non altered digital path of a high quality setup has. But I probably didn’t hear the best possible BACCH setup.

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Certainly Al has praised the DAC in the SP before. But do not know what we know about the ADC other than what TAS said about the DAC and ADC together: “Dr. Choueiri won’t say who makes the ADC and DAC chips, only that they have state-of-the-art jitter control, are customized by Theoretica for implementation in the processor, are of the sigma-delta type, and operate at a resolution of up to 24-bit/192kHz.”

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The DAC operates at 24.192, the ADC 24.96. It is fine for nearly everything. But it is not Gryphon Commander, Legato, and Apex quality. This should be something that is easy enough to grasp. Perhaps after the upgrade it will be a lot closer.

I love my BACCH-SP adio. Love love love it!
Come on over and I will demonstrate the sound I am hearing.

Enjoy your vinyl au natural!

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I think I have this whole Vinyl thing solved.

I listened to a side of an album Bacch Free. I made notes about what I heard.
Listened again through the BACCH and came up with how it could be that I prefer the vinyl straight.

I figured it out.

A few months ago a friend came over who, in order to try to solve some issues he was having with the sound, had me try playing with Mono Correction. This lets you tune the depth of your sound-field. On my BACCH, -6.0 is the default. I was happy forever with that until I tried -3.0. The back of the room is now bottomless. Things stretch out depth-wise. I have been using that mode pretty much all the time.

Anyway, using switching from bypass mode and a couple of different filters I saw that the difference between pure analog and BACCH, the way I have been using it is the depth. I switched mono correct to -6.0, the soundstage flattened everything like a certain preamplifier.

It seems the pure analog signal is compressed front to back. Like someone said, it is like seeing an orchestra from the front row, vs. 20 rows back. Everything is right up front and snappy! So the reason why I noticed a difference is, the setting I am used to (and seem to prefer) is the depth set to -3.0 and all the depth it brings. Noice!!

So, the reason why I noticed a difference BACCH-free is because I chose to make it that way. This pleases me as I can now return to just listening to everything with the BACCH. If I feel like hearing the pure analog sound (with BACCH enhancements) I just choose -6.0.

I love Edgar. He seems nice!

P.S. Sorry I brought all this up.


No apologies! Very interesting and relevant. Thanks!

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The thing is, I think -6.0, the default, is probably the most natural. -4.5 and -3.0 are lets say, “enhanced modes”. I wonder if anyone else has tried these settings?

They are found on control panel #349, in the lower left Quadrant, Galaxy 2 and 3. Just by the settings we should never try. It wouldn’t be prudent.

Based on your previous posts in the Summer, I did play around with mono component correction. Some music I preferred at -3.0 and others at -6.0, just as you described. Felix Laband (electronica) was probably with maximum effect and Dominique Fils-Aimé (soul/r&b) the opposite. Before long I got lazy though and simply stuck with 4.5!

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Thank you so much for that reply!!!
I fully understand and fully, fully, fully agree with you. Fully!

Electronic Music, Felix Laband being a 100% Ace Example, sounds really good with more depth!

I listen to a lot of Electronic and just generally spacey music. The added depth amuses me.

But I was listening to something where the added depth bothered me. It was vinyl. My first thought was, this can’t be better without BACCH Purification. But it was. And I am very happy to fully understand why so I can control it like a pro and move on with my studies while BACCHing out!

It’s a big BACCHing Relief!!!

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Do you keep a settings log?

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I am thinking this will cajge once you upgrade rocessor in ADIO to handle BACCH dSP13. That lifts several veils snd improves 3D image clarity. Removes fuzzines around images.

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