Theoretica Applied Physics BACCH


I know that I still believe with BACCH4Mac, changes to a system (components, cables, etc.) will be evident in how the system sounds. BACCH4Mac does not alleviate the need for a system with excellent sound quality…

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I still hear the tweak changes. I posted a bacch4mac Frequency Response plot of a USB cable with tuning ring. The binaural mic Frequency Response plots were flatter with the ring than without. But I ended up preferring without the tuning ring since more recording background info was being lost with the ring on that cable in the position that sounded best to me. It was only noticeable on some recordings and it was more toe tapping without the tuning ring once I went back to check tweak viability over time.


I remember I have commented on that graph now. Thanks! It is good to know the tweaks and cables still matter, or maybe not. :laughing:

I guess they do to me though Edgar calls it psycho-acoustic trickery.

I personally do not feel any need to try to convince anyone about the results of adding BACCH to my system. I get to enjoy it, that’s enough for me. If you wish to be testy about it, enjoy the joyride!


One curious thing I found is that some Q.sound recordings were less smooth and cross sound stage transitions are a bit clunkier than with Qsound stereo not cross talk corrected. Bacch4mac offers so much detail that the smoke and mirror editing techniques of Q-sound, sound more like editing techniques. It seems your ear and brain processes the sound with better fidelity than the Qsound technique simulates and needs the cross talk present to deceive your brain on the moving objects location. Where the Chesky binaural recording of moving objects offers better realistic fidelity of a real object producing sound that moved

I believe w sound used out of phase info to create the spacial effects.

This week, I switch it out, and 2, maybe 3 seconds later I switch it back in and that’s that.
It’s working its full magic now. I am amused I enjoyed it in “Exactly Wrong” mode.

I’m a sucker for this stuff. Plain and simple.


I know there are 488 messages before this and it’s possible they’ll already touch on a solution, but this seems like an outlier. I’m going to ask @aangen and anyone else with suggestions to chime in.

I have an MU1. It’s my Roon Core, and I usually use my iPad to play my selections. I believe that makes the iPad my endpoint - please correct me if I’m wrong.

I have a spare Mac Mini, so that’s a plus in considering the Bacch4Mac options.


All my electronics are in a closet that backs up to my main room, so I have no direct access to it unless I walk to the hall and step into the closet.

So I’m confused. What do I need to try the software version of Bacch4Mac, utilizing my Grimm MU1 as the core? Or should I give up on that and get one of the Audiophile versions that uses the Babyface interface? And if so, will that allow me to use my iPad to control which music I’m playing?

Broadly, what is recommended to try this stuff, while still utilizing my MU1?

Edit: and I’d prefer to continue using my separate DAC as well. I think the Babyface claims to offer DAC function, but that doesn’t sound interesting to me.


Are you considering the BACCH4Mac Intro or Audiophile versions? I am not a Roon User so please excuse my basic question. Can you verify that your Grimm MU1 is feeding directly to your DAC? This is my assumption. I am assuming you are using the IPad to control the Roon Core. If what I assume is true, you would need an Audio Interface to get the digital signals from the Grimm MU1 into the Mac Mini. Something like this would work: MUTO 8D 8-Channel Interface. You would feed the AES output from the Grimm MU1 into the interface. The interface connects to your Mac Mini via USB. After processing by the BACCH4Mac software, the digital signal is routed out AES via the interface to your DAC. This makes the cost of trial $600 more. I would suggest just trying the BACCH4Mac Intro software using the Mac Mini as your source just so see what the BACCH4Mac filters can do. Then if you like what it does and decide to proceed, I would suggest buying an audio interface like the MOTU 8D to continue using your Grimm MU1. I am sure the Grimm MU1 blows the Mac Mini out of the water as a source as far as sound quality. That keeps the cost of trial low (since you already have the Mac Mini). You might have to buy an AES digital cable if you don’t already have a spare. If you are considering the Audiophile version you would need an audio interface with XLR microphone inputs also. The RME Babyface serves as the audio interface and has XLR microphone inputs. This again makes the trial slightly more expensive. Hope this explanation helps.

You mention your equipment is in a closet not accessible from the listening room. You can startup the Mac Mini and it will not need any actions to start playing music with the BACCH4Mac. You would need to power down with a screen and mouse. I have not figured out how to go headless (no monitor or mouse) for power down.

I forgot about your DAC and IPad questions. I would keep using your DAC. Yes, you would still be able to use the IPad to control the Roon Core.

Your Grimm MU1 is both your Roon Server and Endpoint. Your IPad is merely running Roon software that controls the Grimm MU1.

I have no experience with the Mac version of BACCH so I can’t help you there.

In my system the Grimm feeds into the BACCH-SP, and the BACCH-SP DAC handles the rest. The BACCH takes analog and digital signals in. It converts the digital to analog, adds the magic processing, and converts the signal to digital. At this point the digital signal can be sent out to a DAC. In my situation it goes straight into the internal DAC.

As far as endpoints, I believe the Grimm is still the endpoint. But my BACCH-SP can also be a Roon endpoint. The BACCH offers many options.

I wish I had more knowledge about the software version. I will have to learn about it so I can be useful when discussing it.

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If you get the Bach4Mac. The McIntosh would be Roon Endpoint but Grimm can still run Roon. Your Mcintosh would rn a Roon Daemon to be endpoint. Or you can still have full Roon software on it but not running as the core it will display Roon like your iPad on the iMac screen you Mcintosh uses. You can have full Roon or Roon Daemon active at the same time on the McIntosh. I am not sure if Grimm needs ouput on Aes-EBU. Therefore you might not get grimm upsamples unless you get an ADIO or Dio. The Mcintosh needs the ethernet for software package. The Babyface FS can only take spdif optical digitsl stream or xlr analog inputs. What format does Grimm send out in its digital upsample? Can you feed the digital upsample through ethernet to switch to Mac or spdif optical to babyface FS? I don’t see anything but AES outs in photos.

The Grimm can output AES/EBU and SPDIF at the same time. If the Grimm is used as a server only it is wasted. The Mac could take that SPDIF output from the Grimm and then it would receive all the benefits the Grimm offers. If the BACCH4MAC is used as an endpoint then Ethernet is used but again the things the Grimm can offer are wasted.


The important thing is just call Edgar and get into BACCH! It’s so wack!! Twice wack! None more wack.


The Mac Mini cannot accept the SPDIF RCA input from the Grimm. They would have to buy a USB audio interface with a SPDIF RCA input and an output that is accepted by their DAC. If the DAC has a USB input, the Mac Mini can output that directly to the DAC. This audio interface increases the cost to tryout the BACCH4Mac software. I just wanted to make sure the cost of the BACCH4Mac software trial is understood. I agree that a simple phone call to Edgar would result in quickly identifying the audio interface options available to make it all work.

And who is / where is / how does one contact Edgar?

He is the developer of the BACCH systems. You can contact him at

It would be great if we could send the output of Bacchdsp via UPnP to our beloved streamer.

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