[PorkpieHat]

Going with an outboard DAC is a smart move James. I was held back from adding the current DAC to my BP25 because it is harder to recover the cost if you are selling on the used market (say to upgrade to a BP26   ). You are asking the buyer to make the same DAC and a Pre decision you did and eliminating anyone who already has a DAC from your potential buyers.

If you provide any sort of choices with respect to input (say optical vs SPD/IF), upsampling frequency, etc... please put selectors on the front of the thing and not the back like some people whose name I won't mention for fear of hurting their mother Mrs Fidelity.

More than one input is very useful. Where I am, you can get digital music through your satellite dish subscription and feed it into a DAC, so having an input for the satellite, and another for the CDP, computer, what have you, is very useful. Also nice for audiophile types who like to compare two players at the same time.

Just my 2¢

[James Tanner]

Hi Pork,

At this point we are looking at 5 inputs - selectable from the front panel
2 - SPDIF
2- Optical and
1 - USB.

Balanced and Single Ended outputs.


james

[Rich Carlson]

For what its worth, I am a big fan of AES/EBU inputs, which allow easier integration with some pro gear.

[James Tanner]

Hi Rich,

Yes we may do a PRO version at some point.

james

[dan_lo]

James,
This is good news indeed.
It would be nice  to have a version of the new DAC integrated in the BP26.
I just wanted to order a BP26DA, but I may hold the order now. Do you have a time schedule ?

[James Tanner]

Hi Dan,

It will be about 3 months I would think.
Not enough room on the BP26 for all the digital connections.

james

[kfr01]

Hi Pork,

At this point we are looking at 5 inputs - selectable from the front panel
2 - SPDIF
2- Optical and
1 - USB.

Balanced and Single Ended outputs.
james

Woohoo!  I'll be very interested in buying this.  Handle jitter well and price it reasonably competitively to the Benchmark, and we're in business.

[PorkpieHat]

... price it reasonably competitively to the Benchmark

Or make it better than the Benchmark and charge a premium. There are some of us who look to Bryston when we want to go uptown...

[jethro]

James,

If a USB input is added to the DAC, does this mean that the DAC will have some kind of microcontroller board that can have its software upgraded ?

Are you thinking about using the skeleton of the B100 as a starting place, or going with a more minimalist packaging approach similar to the BP-25 ?

[kfr01]

... price it reasonably competitively to the Benchmark

Or make it better than the Benchmark and charge a premium. There are some of us who look to Bryston when we want to go uptown...

Uptown guy:  A premium is fine.  I said "reasonably competitively," not the same.

[romandoc]

What's to like:
1) It's from Bryston, and that's saying a lot about the upcoming DAC's reliability and support
2) It's versatile, many different inputs and the choice of unbalanced or balanced outputs
3) It uses the Crystal DAC, well regarded
4) It has, presumably, a low output impedance, so it can drive long cables, and has a good voltage out, so it can drive a passive pre, and hopefully it'll be quiet, so it can be used with an amp driving sensitive speakers.

What's NOT to like:
1) The volume control. ALPS? Come on, a stepped attenuator would be much better. There are so many other possibilities for a remote controlled volume control much better than the ALPS.
2) No clock input, so it can't be used as a master clock with sources that output a clock, such as a Lynx audio card in a computer.
3) Trying to aim for a low price point to compete with Benchmark Make it 50% better than the Benchmark for twice the price, and I'll buy it.

Romandoc

[kfr01]

3) Trying to aim for a low price point to compete with Benchmark. Make it 50% better than the Benchmark for twice the price, and I'll buy it.

I'd also pay twice the price for something 50% better from a solid company like Bryston.  

The challenge is actually making it perform 50% better.  From what I've read the Benchmark measures pfg for most practical purposes.  

I think your other "not to like" input is right on, however.  And implementing these changes alone -might- make it 50% better.  Especially the high quality remote control stepped attenuator.  Save me having to buy a remote control passive pre, and I'm sold.

[Jon L]

"What's NOT to like:
1) The volume control. ALPS? Come on, a stepped attenuator would be much better. There are so many other possibilities for a remote controlled volume control much better than the ALPS.
2) No clock input, so it can't be used as a master clock with sources that output a clock, such as a Lynx audio card in a computer.
3) Trying to aim for a low price point to compete with Benchmark Make it 50% better than the Benchmark for twice the price, and I'll buy it."

I agree about the volume pot.  In fact, I would prefer no pot and save a few $$ on the final price as well as better sonics.  For volume-control convenience, unless one wants to go all-out with $$$$, just a digital volume control would be good enough and defeatable.  

A clock input would indeed be very appreciated, especially since I own the Lynx card already  But I really wouldn't expect a consumer DAC to have this capability.  Benchmark doesn't, and neither does the new LavryBlack, both of which chime in at under $1000.

As far as "50%" better than Benchmark.  IMHO IME, there is no DAC in existence today that's 50% better than Benchmark (if a linear, straight line scale is used) at any price.

[thomaspf]

Do you guys really mean a clock input or rather a clock output? A Lynx card in a computer hardly has a better clock than an outboard DAC. DACs with a master clock input make mostly sense when you are doing recording and you want to clock everything from a single master clock. For DACs that rely on an asynchronous sample rate converter for dejittering this also makes little sense since whatever the incoming clock is the signal will be reclocked and recalculated in the AD1986 anyway.

For playback having a clock output from the DAC is more useful since you can then slave your Lynx card to the clock of the DAC. The DACS from Meitner , Universal Audio or DCS can be operated that way. In this case the resampler would do nothing since the incoming stream is frequency locked to the internal clock which is the direct conversion clock.

The Lavry Black is completely different animal since it does not use an asynchronous resampler. If it gets anywhere close to the Lavry Blue it will still have extremely low jitter and there is little sense in adding a master clock input if that would not improve the jitter performance over just a digital input. Weiss also removed their clock input after they figured out their synchronous dejittering.


I am very interested in the USB part of this. My question is whether this connection uses the basic isochronous USB or implements the much more useful asynchronous USB audio protocol. The isochronous USB->S/PDIF adapters are pretty jittery since they need to estimate the clock from the incoming bursts. Asynchronous mode on the other hand has a feedback loop back to the sender and you can make the DAC the master clock of the playback chain.

James could you find this out? I'd be happy to chat about this if you need more data.

Cheers

   Thomas

[James Tanner]

James,

If a USB input is added to the DAC, does this mean that the DAC will have some kind of microcontroller board that can have its software upgraded ?

Are you thinking about using the skeleton of the B100 as a starting place, or going with a more minimalist packaging approach similar to the BP-25 ?

Hi Jethro,

A minimalist approach.

james

[Mike-48]

At this point we are looking at 5 inputs - selectable from the front panel

2 - SPDIF
2- Optical and
1 - USB.

Balanced and Single Ended outputs.

James, I am no expert on this sort of thing, but my understanding is that HDMI can allow moving the highest quality digital data around. That would include 192/24 (though there is precious little of that available).  Still, as more and more players these days seem to have HDMI out, wouldn't it make sense to have HDMI in?  Or am I missing something?

Regards,
...Mike

[Jon L]

At this point we are looking at 5 inputs - selectable from the front panel

2 - SPDIF
2- Optical and
1 - USB.

Balanced and Single Ended outputs.

James, I am no expert on this sort of thing, but my understanding is that HDMI can allow moving the highest quality digital data around. That would include 192/24 (though there is precious little of that available).  Still, as more and more players these days seem to have HDMI out, wouldn't it make sense to have HDMI in?  Or am I missing something?

Regards,
...Mike

The reason HDMI is popular is b/c it can carry both digital video and digital audio signals, including surround sound.  DVI could only carry video signals.  

Since coax spdif is already capable of carrying 24/192 data, there would be no point in having HDMI input on an audio DAC.  On the other hand, optical spdif is usually restricted to 24/96 stream.

[James Tanner]

Yes that's correct - the idea behind version 3 of HDMI is that it would carry vdeo and up to 8 channels of 24/192 in a single connector.

james

[nicolasb]

The reason HDMI is popular is b/c it can carry both digital video and digital audio signals, including surround sound.  DVI could only carry video signals.  

Since coax spdif is already capable of carrying 24/192 data, there would be no point in having HDMI input on an audio DAC.  On the other hand, optical spdif is usually restricted to 24/96 stream.

It's not quite that simple.

SP/DIF is pitifully inadequate when it comes to transmitting top-quality digital audio. Consider Meridian's MHR smartlink interface, for example: this is, to all intents and purposes, three SP/DIF interfaces running in parallel. That provides the bandwidth necessary to send DVD-Audio data from a Meridian player to a Meridian processor so that conversion, bass management, etc. can happen in the processor. You can just about squeeze two channels of 24/192 across SP/DIF, but if you want six channels of uncompressed audio, forget it.

Other, more modern, digital audio standards such as HDMI and Firewire/IEEE1394 can handle this sort of bandwidth quite easily. This is going to become increasingly important once we start to see BluRay/HD-DVD players with hi-def audio formats.

There are other potential advantages too. HDMI and Firewire can be used to send digital audio data asynchronously, i.e. the timing of the eventual output is not derived from the timing of mess up the timing and introduce jitter, and it's the level of jitter which is the only significant factor in one transport sounding better than another.

Not all of this is of relevance to a stereo outboard DAC, of course. If it's stereo only, coax SP/DIF probably will provide enough bandwidth, and, if it's a sensible reclocking design, jitter will be less of an issue too. But, in the long term, one would hope that SP/DIF will be phased out entirely in favour of HDMI (or Firewire, but HDMI is more likely). If, ten years from now, you can't buy a transport with an SP/DIF output, you're going to wish that you'd bought a DAC that supports the alternative.

[Mike-48]

It's not quite that simple.

Thanks, Nicolas, for the added information.  My experience listening to some Muse gear was that using the (proprietary) asynchronous link between transport and DAC opened up the sound in a remarkable way, compared to SPDIF or AES-EBU. It appears that HDMI can fill the same role (and how pleasant finally to have it standardized).

Another issue is that although SPDIF may be capable of moving 192/24, most if not all existing DVD-A at that rate limit the resolution of digital information output by the player to 96/24 or below, in some cases to 48/24.  My understanding (which, again, may be wrong) is that HDMI includes a form of encryptation and that content providers therefore allow the highest rez signals to be transmitted over it.