Article: Berkeley Audio Design Alpha DAC Review

[avreality]

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[daglesj]

Very good thanks.<br />

<br />

One point though..at $5000 its no bargain, relative or not. <br />

<br />

$500 or less...maybe.

[Elprior]

That seems to be a very nice product.<br />

<br />

dCS does all that too, and even more : digital outputs, word sync I/O, dsd, ...<br />

And quite interestingly, the power supply is also having a little hum, when you come close.<br />

Ever done a true comparison (I mean outside a show) ?<br />

<br />

Elp.

[limesinferior]

Thank you Chris for this very interesting review of Berkeley Alpha.<br />

<br />

I have to admit it would be interesting to read your review of a much cheaper component that is making some hype in computer audio community, I got in mind ASUS Xonar Essence STX sound card. <br />

<br />

http://en.expreview.com/2008/10/20/asus-xonar-essence-stx-nice-sound-card-with-snr-up-to-124db.html/2<br />

<br />

I am looking forward to reading your opinion on it, especially when using it directly in connection with some good headphones like Grado.<br />

<br />

thank you,<br />

limesinferior

[audiozorro]

It would be preferable to start a new thread than to hijack the Berkeley Alpha DAC review for a sound card.<br />

<br />

My personal opinion is that the ASUS is a lot of hype. Not that it isn’t a good soundcard but there seems to be a ton of postings on the Internet, but no one has heard it or has posted any listening evaluations.<br />

<br />

ASUS makes several other decent soundcards but I wouldn’t know what makes this one so much better. In addition there are several other good soundcards including the Lynx L22. In general, people have found internal soundcards to be a cheap and decent alternative to doing what CA is advocating here. In fact, I would say that the audio out from my MacBook Pro connected directly to my amplifier is pretty darn good.<br />

<br />

Anyway the Berkeley Alpha DAC is a proven winner with substantive reviews and evaluations and that’s no hype.<br />

[jeroen020]

Hi Elprior,<br />

<br />

Some questions concerning your dCS, I hope you're willing to share.<br />

<br />

Are you using the Delius or Elgar Plus ?<br />

<br />

Which interface are you using ? And is that able to play 192 khz.<br />

<br />

And last, do you upsample, and if so, what is the impact of it, and did you try softwarebased upsampling ?<br />

<br />

Looking forward to your reply.<br />

<br />

Jeroen

[StephanLJ]

Hi Chris<br />

<br />

Thank you for the fabulous review. You are 100 % on time and target. dCS I had, I like the alpha Dac better ... and your site anyway. Keep up the great work. Thank you again for the educational results your site has to offer.<br />

<br />

Greatings Stephan

[limesinferior]

I found the review of Berkeley's Audio Design Alpha DAC very useful, especially the part which compares pros of alpha and minerva. It was not my intention to "hijack" ... anything.<br />

<br />

[Elprior]

Hi Jeroen,<br />

<br />

I'm certainly willing to share .<br />

<br />

I'm using the Delius along with the Purcell (upsampler).<br />

Everything is being played at 192khz (or 176khz depending on my state of mind), although there is an annoying limitation here.<br />

The Delius handles 192khz through dual aes or dsd.<br />

The Purcell can only handle 96khz as an input (whatever the input may be).<br />

<br />

So the upsampling so far is handled by the Purcell.<br />

The benefits I can hear are numerous :<br />

1) There is much more air between the performers, while everything remains connected.<br />

2) The decays are much smoother.<br />

3) The sound is coming to you (wider soundstage).<br />

<br />

Now, I can think of drawbacks too :<br />

1) The pace of the music is somehow quieter.<br />

That is a conclusion I have come to when you are using components that tends to the analogue feeling. You are having a much smoother sound, much more information, air, ... but the rythm is a bit slower.<br />

2) Can't use the Purcell as long as I need a 192khz capable input (as stated above).<br />

<br />

As for using my computer as a drive, I'm still stuck with my loosy components, that ain't compatible with ASIO.<br />

So I'm being SRC everywhere in my windows xp based system. I'm willing to give the Lynx card a try, but a forum here is showing someone that can play easily through the dCS, and another one who can't (PLL issue it seems).<br />

Hopefully, I'm about to test the Mac solution with a friend of mine.<br />

I'll let you know where the thing goes with it.<br />

<br />

Elp.<br />

[Young Skywalker]

Hi Chris,<br />

<br />

Thanks for the review although I didn't really learn anything I didn't already know from my own audition, albeit brief, of the Alpha DAC in a friend's system.<br />

<br />

I wonder if you compared the Minerva and Alpha DACs using a digital interface that is common to both, i.e, the AES output from the Lynx AES16 PCI card in your PC (or Lynx AES16e in the case of your Mac)? If not how do you know that the sonic differences you noted were not, at least in part, attributed to the Lynx AES versus Firewire interfaces rather than the DAC chip, filtering or analog output stage?<br />

<br />

Best Regards,<br />

Aaron

[Purite Audio]

It is a good piece of writing, but like any review it can only tell you so much, it is important to hear every component in your own system, and if possible compare to the other 'possibles' keep up the good work Chris.

[jeroen020]

Thanks a lot Elp.<br />

<br />

So far I didn't buy an dCS, but it is on my shortlist. <br />

<br />

When you did some testing with your friends Mac it would be great to hear about it.<br />

<br />

Jeroen

[shaq]

Great to hear about this fine sounding equipment.<br />

<br />

First of all, technically- I known I don't need a preamp to play from my computer server when I use the DAC. Can I plug my Tom Evans Phono Preamp into the Berkeley and still hear great vinyl sound?<br />

<br />

And what sound difference am I likely the experience when I eliminate the BAT tubes in the chain? My amp is solid state.<br />

<br />

Thank you<br />

[Purite Audio]

The signal from your phono is analogue.

[The Computer Audiophile]

Coops is exactly right. Your phono signal is analog and the Alpha DAC does not have an analog input.<br />

<br />

If you remove the BAT tubes you will remove the sonic signature of the BAT tubes. All equipment has a sonic signature and acts like a filter down stream. Removing the BAT tubes will remove the filter.

[shaq]

So, in order to incorporate a Berkeley and keep my phono- I have to utilize a preamp to connect my phono pre to. Thus I will inevitably run the DAC into the preamp as well- all to go to the amp?<br />

<br />

I cannot run the Berkeley directly into the amp without giving up phono.<br />

<br />

Am I misunderstanding something here?<br />

<br />

<br />

<br />

[The Computer Audiophile]

Correct. Unless you convert analog to digital before the Alpha DAC.

[shaq]

Trying not to be a doofus here, but ...<br />

<br />

If I convert my phono to digital so that I can utilize the DAC and eliminate my preamp, I will be defeating the very analogue sound I enjoy, correct?<br />

<br />

Practically speaking, running the Berkeley straight into my amp eliminates my phono option. I have to stick with my preamp if I want to maintain my phono as best as possible. ???<br />

<br />

thank you<br />

[The Computer Audiophile]

Exactly right. I just wanted to through the option out there for you to consider.

[jay]

Sorry for the dumb question, but wouldn't using the digital volume control on the Alpha essentially eliminate the "bit-perfect" signal going to the DAC inside? I understand that it would be bit-perfect when it hits the unit, but wouldn't the digital volume be applied before the DAC stage? Is there a type of digital volume control that hits the analog stage after the DAC got the bit-perfect signal?

[The Computer Audiophile]

Hi Jay - Very good question and one that is best addressed by the people at Berkeley Audio Design. But, I will give you my opinion on this one for what it's worth. A digital volume control, as well as many other things, will most likely change the audio stream so it's not bit perfect. However, delivering a bit perfect stream to the unit itself is probably OK with the Alpha DAC. I'm guessing most other DACs change the audio stream sometime between when it hits the unit and when it's delivered to the actual DAC chip. Upsampling and downsampling are very popular whether a consumer is aware of it or not. For example some DACs allow you to enable upsampling while others upsample without you even knowing. I guess the signal is likely to be changed at some point before the actual DAC chip with most DACs. I think if implemented correctly a digital volume control can be great as it allows you to remove the filter of a preamp and additional cables. <br />

<br />

This is just my guess on the situation and it could be totally off base. Hopefully someone can jump in and lend a hand with the subject :=)<br />

<br />

<br />

<br />

[Elprior]

Hello,<br />

<br />

very good question indeed.<br />

I think the answer is up to the implementation. You can't really know what's going on in your dac, unless you designed it or asked explicitely the constructor, and obtained a clear answer.<br />

<br />

Nevertheless, with such units as the Alpha Dac, you can bet Chris' explanation is the expected result.<br />

They must have designed it as good as possible, so as to bypass the use of a preamp.<br />

<br />

Still, I know vendors that used to think the same, and changed their mind with high-end setups, where the use of a preamp seems to add more than it removes...<br />

Again, this is all a question of taste (and money a bit).<br />

<br />

I can't wait to get an explanation from Berkeley Audio Design.<br />

<br />

Elp.

[jay]

The Berkeley Audio Design explanation (if they want to reveal their secret!) will certainly be interesting. I suspect your answer is right, btw, Chris. I have only a very basic understanding of digital volume control, but have always assumed it to be a killer of "bit-perfection," based on my very limited reading and understanding. Regardless...if it sounds great, I don't personally care at all, and would use the feature. Just morbidly curious more than anything.<br />

<br />

This review has thoroughly peaked my interest in this DAC, so thank you. As a guy who's been questioning the pre-amp in my all-digital system since the beginning (yet it's still there after numerous attempts to remove it), I applaud the digital volume feature and I'll assume at this level of technical design (and cost), they would not have wasted their time with a digital volume that wasn't extremely well-done. Can't wait to try it myself. Attenuation, in my experience, is the most tricky part of this whole "all-digital" equation and one that holds the most "you must just try this or that in your system before you know what sounds best (or worse, in many cases)." We've all heard it done "not well" I suspect and quickly spent gobs of frustrating time and money getting that part of the chain "out," or more likely "replaced with something less objectionable." And Elp, I also think you're dead-on in that for whatever reason, there are occasions where the pre-amp seems to add more than it takes away (again, that's with only the most well-done ones I've tried). Another head-scratcher for me, but I long-ago gave up trying to think of that step as just invisible attenuation--my passive pre is in line because the system just sounds better with it for some reason. I hope the Alpha gives me cause to remove it--only because that would then mean my system, for the first time, sounds even better without it! <br />

<br />

The soundstage comments alone have me very excited to try this DAC. Everyone else experiencing that same soundstage breadth and depth improvement relative to their current DACs?<br />

<br />

[tmfidelis]

Please allow me to share my thoughts regarding several questions I've been reading regarding DAC implimentation:<br />

<br />

1. Several of today's DAC take the "bit perfect" data and clock to a different frequency.<br />

2. Controlling volume control for many is an excellent solution - DACs with analogue attenuation may have issues as well with the parts used in the analogue attenuation. Higher-end preamp manufactures always have issues finding transparent volume controls and higher quality volume pots may cost more than the DAC.<br />

3. For those desiring to combine analogue source material, whether it be phone of L-R from a surround system, may consider a single-ended or balance switch that feeds the amps directly.<br />

4. Some users will prefer to drive the DAC, (w/volume), directly into the amps, others may prefer using them with a preamp.<br />

5. There is much more to come but 1-4 may help some of the readers.<br />

<br />

Regards.....

[kana813]

Chris-<br />

<br />

It seems to me that some damping material on the bottom of the DAC could solve the hum issue.<br />

<br />

Let me know the dimensions of the bottom, and I'll send you some.<br />

<br />

Aloha,<br />

<br />

Dan<br />