Taking orders :)

[Doc B]

There will be a switch to allow choosing USB or SPDIF input.

 

[John Swenson]

Yes it will work with the SBT and EDO. The new USB is going to be UAC2, which means it can go up to 24/192. What Doc doesn't even know yet is that it is going to be multi-channel, so some time in the future we can offer a board that plugs into the extension port and connects multiple DAC boxes so you can get up to 8 channels over the one USB connection.

The downside of UAC2 is that it will not work out of the box with Windows, it will take a UAC2 driver, just like all the other UAC2 DACs out there now. It will work out of the box with Mac and Linux.

There are going to be three inputs, S/PDIF coaxial on a 75 ohm BNC, S/PDIF optical (TOSLINK) and USB (UAC2). There will be a switch to select between them. I don't have any plans to do autodetect, it is really difficult. Most sources don't actually turn off the carrier when not playing, so it becomes a task of detecting "silence", it's not so easy to do reliably without unintentional source switches.

John S.

 

[BNAL]

John,

Thank you for the information. I have been thinking of dropping the Touch and getting either a Mac Mini or building a Linux based computer, but think I will keep the Touch and power supply I built based on your design and use it with the Bottlehead DAC via the USB out.

 

[debk]

John,
Thanks for the information.  I am excited for the DAC, I am sure it will be awesome!
Deb

 

[denti alligator]

John,
will 24/192 be available over S/PDIF?

 

[John Swenson]

Yes, 24/192 will work over S/PDIF coax. I'm using the fastest TOSLINK receiver I can get, which should allow 192 via optical, IF the transport supports it.

Many devices use the cheaper slower optical modules which won't work for 192, so many transport designers limited their optical out to 96. So IF yours supports 192 over optical it should work as well.

John S.

 

[tdogzthmn]

Support for Interger Mode would be nice too, many of the audiophile players now have the ability to utilize DAC's which support it. 

 

[xcortes]

Wasn't really a matter of getting rid of the transformers. I just did a lot of listening to transformer vs. resistor and found that the bass was a lot better to my ear with the resistor, and the mid and treble sounded very close

At the very beginning of this project John Swenson mentioned the transformers worked very well as low pass filters. May i ask if the current iteration is completely filterless or are you implementing some analog filter?

Thanks

 

[Doc B]

The version we are using this week uses a cap as a simple 1st order filter. I found, as usual, that a line level transformer didn't give me the best bass.

 

[xcortes]

"The version we are using this week". Classic!

Thanks

 

[Doc B]

John shot me an email last week with a status report. Looks like about four weeks before we have a prototype of the latest version running.

 

[Chris]

Sounds like some premium parts are going into this thing like the BeePre.. I like it...

 

[ssssly]

Forgive me if it has already been answered and I missed it.

Will the USB input be asynchronous?

 

[Doc B]

I'm away from my notes today. There are two pretty big windfalls in my yard that have been there for weeks, PB loaned me a chainsaw, and it's sunny, so I'll be playing gardener today. I believe that John has something he feels is a superior way to deal with USB and hopefully he will weigh in on that when he has some free time.

 

[tdogzthmn]

Has a list of all the supported sample rates been posted?  I cant remember seeing them all listed yet.

 

[BNAL]

John has posted that the DAC will support rates up to 24/192 via USB and coaxial. As for optical he is working on supporting the same rate, but that does not seem to be confirmed. Not sure about the other sample rates.

 

[tdogzthmn]

The most common sampling rates are: 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz and 192 kHz.  I had wanted to know if all of these are supported since I own digital files for each of the above and hoping the DAC can handle them with having to upsample to 192 kHz.

 

[Doc B]

Yes, it will be able to do all of those sample rates as well as 176.4

 

[tdogzthmn]

i've been looking into making my 2 channel setup into a 5.1 and it looks like this DAC will be capable of playing back my multi channel files.  Would I need to purchase 5 separate kits to do this? 

 

[Doc B]

It's a stereo DAC, so for six channels you would need three kits. Be advised that it may be a while before we have this ability to parallel three or four DACs available, i.e. it may not be ready in the first release. The beauty of the auxilary port that John mentioned is that we can add new features as we have time to develop them and use that port to implement them.