• Berkeley Audio Design Alpha DAC Review

    Over the last few months I've talked more about the Berkeley Audio Design Alpha DAC than perhaps any other product. The Alpha DAC appeared on the CASH List from the very beginning and has since been the subject of several reader discussions here on Computer Audiophile. Under normal circumstances I would be concerned as frequently discussed products often don't live up to the hype they've generated. This however is not a normal circumstance. The Berkeley Audio Design Alpha DAC is seriously out of this world. At $5k it's a relative bargain in high-end audio terms and there is nothing like it available today.

     

     

    Berkeley Audio Design

    Berkeley Audio Design was founded by René Jaeger, Michael “Pflash” Pflaumer, and Michael Ritter. All three gentlemen are well known for their previous work at Pacific Microsonics. Pflash Pflaumer is the co-inventor of the HDCD process, in addition to writing all the digital algorithms used in the Pacific Microsonics Model Two. The Model Two is commonly thought to be the best ADC / DAC produced in recent memory. Unfortunately there were only 150 Model Twos produced and they have long since been out of production. This past weekend on my trip to Seattle and the San Francisco bay area I had a chance to meet with all three founders of Berkeley Audio Design. I talked to René Jaeger over breakfast in Seattle, before heading to the Bay Area. Then I spoke with Michael and Pflash during lunch at Eccolo in Berkeley, CA. All three Berkeley Audio Design founders are first class guys who were very eager to discuss the Alpha DAC and computer based audio in general. After discussing some technical details about the Alpha DAC with Pflash I realized that he has likely forgotten more information than I'll accumulate over the course of my entire life.


     

     


    Alpha DAC Front


    Berkeley Audio Design Alpha DAC
    click to enlarge


     

     

    Alpha DAC Features

    As I said in my opening paragraph, the Alpha DAC is seriously out of this world. Sonically I've never heard better. In addition to sound quality the Alpha DAC has some fabulous features that are indispensable. The single most important feature of this DAC is its ability to decode HDCD and illuminate an HDCD indicator when HDCD encoded content is detected. One constant in the world of computer based audio is the worry that looms over listeners wondering if their computers are outputting bit perfect data to their DACs. The HDCD indicator on the Alpha DAC is not foolproof, but there is a 99.99% chance that a computer is outputting bit perfect data if the HDCD indicator is illuminated upon playback of an HDCD encoded track. This is because the HDCD flag is located on the 16th and 24th bit of 16/44.1 and 24/44.1-192 content respectively. As I noted in a response to a reader in September, "If the HDCD indicator illuminates on the Alpha DAC, the data is uncorrupted. Theoretically, it is possible to alter HDCD data using specialized software while not touching the LSB, but all of the typical mechanisms that might alter data in a computer environment such as level shifting, dither, SRC’s, etc. will definitely affect the LSB. And, if the LSB is altered the HDCD code is lost. So, as a practical tool, presence of the HDCD light indicates no alteration of the data file."

    The Alpha DAC's front panel display indicates the current sample rate or volume level depending on the listeners selection. This is an easy way for listeners to verify that data coming out of their computer has the correct sample rate. Avoiding software sample rate conversion (SRC) is a high priority for many listeners. The Alpha DAC display removes almost all ambiguity from the computer playback process. If you're playing a 24/176.4 track from Reference Recordings and the Alpha DAC is not indicating the presence of HDCD and the sample rate is not indicating 176.4, then you know you have some configuration issues. Compare this to a user without the Alpha DAC who thinks his computer is performing at its highest level even though the sound is not quite right. I think we'd all like to know when the sample rate is wrong and remedy the situation ASAP so we can get back to listening unaltered music. We've all had issues with our audio systems, traditional or computer based, and we've all jumped for joy when inserting a component that solves the issue or when removing a component causing the trouble. I've said to myself more than once, "how could I have listened like that for weeks without knowing something was wrong?" The Alpha DAC gets us one step closer to identifying sources of imperfect sound. In my conversation with Pflash a couple days ago he stated that the display of the Alpha DAC is updated at the very beginning of a track. Thus, the Alpha DAC reads a 176.4 track and updates the display instantly upon playback. Following the sample rate update the display totally "disengages" (my word, not Pflash's) from the rest of the DAC. This is among many other design elements that contribute the Alpha DAC's stellar sound quality.

    Possibly the most underrated part of the Alpha DAC is its ability to bypass a pre amp and connect directly to a power amp(s). The Alpha DAC has its own digital volume control that is as well implemented as I've ever heard. Trust me, I'd have a pre amp in my system in a heartbeat if I thought the Alpha's volume control degraded the sound in any way. As a test I connected the Alpha DAC to a pre amp and was so disappointed I reverted to the pre amp-less configuration in under two tracks. I spoke to Berkeley Audio Design's Michael Ritter about the digital volume control and he indicated that even the best pre amps in the industry can degrade the sound coming from the Alpha DAC. The digital volume control and analog output stage in the Alpha DAC are very solid. That said, I do know people using pre amps with their Alpha DACs. Some people must use a pre amp for the analog inputs and others just like the sound of their system using a pre amp. When the Alpha DAC is used with a pre amp the optimal volume setting on the DAC is 54 dB. The main point to keep in mind is the Alpha DAC offers listeners options. The Alpha DAC has traditional DAC inputs and outputs. Both single ended RCA and balanced XLR connections are available for the analog output. The usable inputs are limited to AES/EBU, S/PDIF, and Toslink.

    Shortly after the Alpha DAC arrived I noticed a barely audible hum coming from the DAC. I immediately thought something was wrong so I contacted Michael Ritter seeking an answer. What Michael told me only solidified my belief that sound quality was the foremost concern of the Berkeley Audio team. He explained that the Alpha DAC has two totally separate power supplies for digital and analog, and two power transformers. The dual bobbin transformers used in the Alpha have very high isolation between the primary and secondary windings that provides maximum immunity from line noise. One side effect of this high isolation is a narrow area of magnetic field that causes the bottom of the DAC to hum a little bit. Berkeley Audio Design could have opted for an absolutely silent solution at the cost of sonic degradation. Listeners will be happy to know the hum is inaudible when listening to music even at the lowest volume the Alpha DAC is capable of producing, 0.1 dB.


     

     


    Alpha DAC Rear


    Berkeley Audio Design Alpha DAC
    click to enlarge


     

     

    The Sound

    During the Alpha DAC review I used two different computer sources. One source was my Mac Pro running OS X and a Lynx AES16e PCI-Express digital I/O card outputting AES/EBU to the Alpha DAC. The other source was my very inexpensive Dell Inspiron 530 running Windows XP and the Lynx AES16 PCI digital I/O card. I played back WAV and AIFF files with sample rates from 44.1 to 192 kHz. The software applications used were iTunes 8 (OS X), Amarra (OS X), Foobar2000 (XP), and MediaMonkey (XP).

    The single most recognizable and talked about characteristic of the Alpha DAC is its soundstage. I describe the soundstage as expansive, transparent, and three dimensional. The soundstage produced from the Alpha DAC is unlike anything else. It is perhaps what makes the music reproduced through the Alpha DAC sound live instead of recorded. Listening to Crown Imperial from the Dallas Wind Symphony at 24/176.4 was truly an awesome experience. The music appeared to float in front of my listening chair and reach all the way to the back wall of my listening room at times. The transparency of the Alpha DAC is unparalleled by any DAC I've heard in recent memory. This includes some very highly regarded DACs at the 2008 Rocky Mountain Audiofest. The Alpha DAC's ability to remain extremely resolving at very high and low frequencies is astounding. Very complex orchestral material is no challenge for the Alpha DAC. Each instrument has clear separation from the top to the bottom of the spectrum. Since the Alpha DAC / Lynx combination supports everything up to 24/192, I listened to a plethora of high resolution albums during the review period. In fact I must have played the Reference Recordings HRx material at 24/176.4 more times than I can count. In order to truly give the Alpha DAC a workout and push the DAC to its limits, high resolution material is a must. Don't get me wrong the Alpha DAC handles 16/44.1 material like no other, but why listen to low resolution when you don't have to? Transients through the Alpha DAC were highly dependent on the source material and components. This is another feather in the Alpha DAC's cap as the DAC does not produce sound that it isn't presented. For example, using iTunes and the AES16e card on my Mac appeared to produce what I call rolled transients. The sound didn't quite have the edge present in the original recording, but this was not a fault of the Alpha DAC. Switching over to my XP machine with a Lynx AES16 and MediaMonkey the transients were clearly present with authority. Listening to Fanfare for the Common Man at 24/88.2 (HDCD) was an eye-opener. The attack of the drums was intense at high volumes. I almost felt like the "blown-away guy" photographed by Steve Steigman for the popular Maxell advertisements of the late 1970s and 1980s. I did listen to each interface on the Alpha DAC and settled on the AES/EBU as my favorite. I must admit this was not an apples-to-apples comparison because I used the Lynx card as my digital I/O for the AES/EBU output and I used the Mac's built-in TosLink output as another digital I/O. Hardly a fair comparison, but I used available interfaces that many readers will consider when using the Alpha DAC or the DAC of their choice. Overall the sound of reproduced music through the Berkeley Audio Design Alpha DAC was absolutely stunning. I have very good reason to include the Alpha DAC on the CASH List without hesitation.

    My review of the Alpha DAC would not be complete with comparing it to the competition. I consider the two premiere DACs at the moment to be the Alpha DAC and the Weiss Minerva. (When the full Sonic Studio Amarra software/hardware package is released I expect it to be very compelling as well). I came to this conclusion through my own listening tests, as I did have both units here at the same time, and based on the frequent communication I have with Computer Audiophile readers. Even at Rocky Mountain Audiofest I ran into a very nice CA reader who was inquiring about an Alpha DAC versus the Minerva. It's a very hot topic to say the least. First and foremost both DACs are capable of incredible sound, as evidenced by my reviews of each DAC. Provided you have the proper interface you won't be disappointed by either DAC. Deciding which DAC to chose is entirely personal and depends greatly on the listener's taste, available interfaces, and feature requirements. Both DACs are right around $5,000. In my opinion the major sonic difference between the two is soundstage. I described the Alpha DAC's characteristics in detail above so I'll get right to the Minerva. The Minerva has a much more focussed soundstage that may be narrow to some listeners. On the other hand this focussed and tight soundstage is exactly what some listeners are seeking. In a way the Minerva is like plugging into the soundboard to make a live recording and the Alpha DAC is like placing microphones elsewhere in the venue. Next those considering each DAC should consider the interface required. If you need FireWire the choice is rather easy. The Minerva has FireWire 400 in addition to other interfaces whereas the Alpha DAC has the three aforementioned traditional interfaces. The Minerva also has digital outputs should you need it as a FireWire to AES interface. To further narrow down the choice between DACs the listener should consider the features of each DAC. The Alpha DAC is very strong in this department with the built-in volume control, remote control, ability to bypass a pre amp, HDCD decoding and indicator of bit perfect audio, and the sample rate display on the front panel. In addition to these considerations I strongly recommend potential purchasers contact a local dealer to discuss their needs. Berkeley Audio Design and Weiss have lists of dealers available on their websites.

     

     


    Alpha DAC


    Berkeley Audio Design Alpha DAC
    click to enlarge


     

     



    Conclusion

    There is a very valid reason why Berkeley Audio Design is selling Alpha DACs as fast as it can produce them. The Alpha DAC is simply stunning. The Berkeley Audio Design team is one of the most respected in the industry. They have succeeded in their goal of making a very high level of fidelity available to music lovers everywhere. That is unless the music lover is in a ROHS required country, but that's a story for a different day. At $5,000 the Alpha DAC is a high-end audio bargain. This level of quality and features could honestly sell for twice or three times the price. Every Alpha DAC owner and audiophile I've talked to who has heard the DAC has been very impressed. In a recent DAC shootout for the Bay Area Audio Society the Berkeley Audio Design Alpha DAC took first place hands down. I would not be surprised to see the Alpha DAC ascend to the top of many lists and receive much deserved accolades in the weeks and months ahead. Whether I'm using Mac OS X or Microsoft Windows the Alpha DAC from Berkeley Audio Design is my reference DAC for the foreseeable future.



     

     

    Manufacturer: Berkeley Audio Design, LLC
    Phone: 510-277-0512
    Email: info@berkeleyaudiodesign.com
    Alpha DAC Price: $5,000
    Dealer List



     

     

    Associated Equipment: Mac Pro, Lynx AES16e card, Kimber USB cable, Cambridge Audio DacMagic, Weiss Engineering Minerva, Benchmark DAC1 PRE, Kimber Select cable, Avalon Acoustics speakers, Focal Electra Be series speakers, McIntosh tube amplification, Virtual Dynamics power cables, Richard Gray's Power Company cables, Bel Canto USB Link.

     

     
     

     




    Alpha DAC Details from berkeleyaudiodesign.com:




    PRODUCT HIGHLIGHTS
    •Highest audio quality DAC
    •All distortion products below one part per million
    •Unequalled interpolation technology up-samples 44.1kHz CD’s to almost 176.4kHz quality and
    provides superb fidelity at all sampling rates from 32kHz to 192kHz
    •IR remote control of all functions including volume and balance allows direct connection to power amplifiers
    •Advanced input signal jitter rejection
    BADA encrypted input allows future support of HDMI and other DRM formats
    •Designed by Pacific Microsonics Model One and Two design team

     

    CONTROLS & INDICATORS
    •Input selects AES, SPDIF, Toslink or BADA inputs
    •Lock LED indicates input signal lock
    •HDCD LED indicates HDCD code detected
    •Phase sets absolute phase
    •Invert LED indicates absolute phase inverted
    •3 digit LED display of Stereo/L/R attenuation, Sampling Rate and Filter type
    •± controls set attenuation level and select Filter type
    •Mode selects Stereo/L/R attenuation, Sampling Rate and Filter type display modes
    •Dim selects multiple display brightness levels

     

    SPECIFICATIONS
    •Input sampling rate: 32kHz to 192kHz
    •Input word length: 24-bit
    •Two channel analog stereo outputs: XLR balanced and RCA unbalanced
    •Digital Inputs: AES - Single XLR 110?, SPDIF - BNC 75?, Toslink – Optical, BADA encrypted - RJ-45
    •HDCD decoding detects 16-bit flag at 44.1kHz or 24-bit flag at all sampling rates
    •Multiple digital filter options
    •Multiple units can be combined for multi-channel/surround reproduction
    •Balanced analog output level: +18dBu maximum, +12dBu or lower recommended
    •Unbalanced analog output level: 3.25Vrms maximum, 2Vrms or lower recommended
    •Digital attenuation and balance control: 0.1dB/step with .05dB/step trim, 60dB range
    •Frequency response at ? 88.2kHz sampling rates: ± 0.1dB from < 0.1Hz to 35 kHz, - 3dB at 59kHz for 176.4kHz and 192kHz sampling rates
    •Distortion at recommended levels: all products ? -120dBFS
    •THD+N at maximum level: < -110dBFS
    •Setup stored in non-volatile flash ROM
    •Firmware field upgradeable through signal inputs
    •Enclosure dimensions: 1.75”H X 16.5”W x 10.4”D, 19” rack mount option
    •Mains voltage: 100/120/240VAC, 50/60Hz
    •Power consumption: 25W

     

     

     
    Comments 117 Comments
    1. davidR's Avatar
      davidR -
      Yes, I'm using a Digi Design 003 with a Black Lion Audio Micro Clock and am quite happy with the reproduction.
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Hi Bob - I did a little research into your analysis and found it's over-simplifying things a bit. I am not qualified to get into the very technical discussions but I do know this is a much more complex issue that can be explained in a few paragraphs by either of us. If it was simple everyone would produce outstanding DACs.<br />
      <br />
      Anyway, thanks again for your analysis. It's really great to read intelligent opinions from readers around the globe, even if we don't all agree.<br />
      <br />
      <br />
      <br />
    1. avreality's Avatar
      avreality -
      Hi, Chris<br />
      <br />
      I finally got my alpha DAC few days ago, but only able to hook it up last night. It's a amazing DAC, in addition to the soundstaging, the vocal and the musical instruments are so alive, just like in my room. Thanks for your recommendation.<br />
      <br />
      I also copy the file from HRx sampler in WAV and AIFF format (using Max) in my iMac, connecting to the DAC by a optical cable (Wireworld SupraNova), and to K&H O300 directly. However, from the screen of the DAC, the iMac is outputting 96kHz signal to the DAC. Is there anything wrong in my iMac setting?<br />
      <br />
      With regards,<br />
      <br />
      WF
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      Hi avreality - Glad to hear you like the DAC. The iMac optical output is limited to 24/96 for OS X. If you use bootcamp and install Windows Vista the optical output will support 24/192.
    1. avreality's Avatar
      avreality -
      Thanks for your reply, Chris.<br />
      <br />
      It's really frustrating, I switched my OS from Window to Mac , partly because of the better performance of itune in mac than that in Window. Is the AFI1 or Vesta from Weiss the only solution for 24/192 output ?<br />
      <br />
      By the way, will the light of HDCD on when the output from my iMac is bit-perfect? What can I do if the light is off when playing music in iTune?<br />
      <br />
      Thanks in advance for your help.<br />
      <br />
      av
    1. audioengr's Avatar
      audioengr -
      Bob Stern - I agree with your analysis. It's independent of the DAC actually. The resolution is ultimately impacted in order to achieve proper listening levels.<br />
      <br />
      You can get some relief with some USB and WiFi interfaces that change the data from 16/44.1 to 24/44.1. the extra 8 bits gives you about 10dB. After this you start whittling away LSB's. Sonos and Empirical Audio USB are two examples that change 16/44.1 into 24/44.1.<br />
      <br />
      The optimum scenerio is to have a DAC that can be reduced in volume about 10-12 dB in the analog domain, or at least without affecting the data. If one could do this, then 24/44.1 data could be reduced in volume digitally an additional 10dB without impacting the data. The 8 bits of additional "padding" gives you about 10dB. This way remote controls such as Touch and iPhone can be used from the listening position and you dont need a remote for the DAC.<br />
      <br />
      One would start by calibrating with a quiet track by adjusting the non-destructive volume control until a good listening level is achieved. Then, when a louder track comes on, one can adjust the volume down by as much as 10dB digitally without impacting the resolution. The difference between the loudest and quietest tracks I have found is less than 10dB.<br />
      <br />
      This is exactly how my new Overdrive USB DAC works BTW.<br />
      <br />
      A 3:1 or 4:1 transformer would probably do the trick for the Berkeley. Just enough to reduce it about 12-14dB.<br />
      <br />
      Steve N.<br />
      Empirical Audio
    1. audiozorro's Avatar
      audiozorro -
      Please confirm if the following is correct or if I am misunderstanding something:<br />
      <br />
      Converting by 16/44.1 files to 24/44.1 will not increase the volume of the files during playback. But it will allow me to digitally reduce the playback volume by about 10dB without losing any information.<br />
      <br />
      Or said another way, any digital volume control on the playback of a 16/44.1 file will degrade the sound.<br />
      <br />
      Thus, I should have 24-bit audio files if I want to use the volume control on my Apple remote or iPhone and do not wish to degrade the sound.<br />
    1. audioengr's Avatar
      audioengr -
      "Please confirm if the following is correct or if I am misunderstanding something:<br />
      Converting by 16/44.1 files to 24/44.1 will not increase the volume of the files during playback. But it will allow me to digitally reduce the playback volume by about 10dB without losing any information."<br />
      <br />
      Correct, once you have a comfortable listening volume, an additional -10dB comes at no degradation to the data.<br />
      <br />
      "Or said another way, any digital volume control on the playback of a 16/44.1 file will degrade the sound."<br />
      <br />
      Yes, but you may not be able to hear it depending on the resolution of the system, the software and the amount you are reducing the volume. Sometimes the software makes adjusments as well. I recommend that you do your own experiments.<br />
      <br />
      "Thus, I should have 24-bit audio files if I want to use the volume control on my Apple remote or iPhone and do not wish to degrade the sound."<br />
      <br />
      24/44.1 files are definitely superior, not only for the DAC, but allow for some volume control. Expect better sound quality too. BTW, 24/44.1 files are also bit-perfect with Vista, and 16/44.1 are not. If your player S/W does not support this, you can get R8brain or Adobe Audition and convert the files from 16/44.1 to 24/44.1. Give it a try. I think you will be pleasantly surprised.<br />
      <br />
      Steve N.<br />
      Empirical Audio
    1. Bob Stern's Avatar
      Bob Stern -
      If your 24-bit DAC has a sample rate converter (SRC), the SRC inherently converts 16-bit data to 24-bit data before it undergoes D/A conversion, so it would be pointless to convert it to 24-bit manually.<br />
      <br />
      I agree with Steve Nugent's recommendation if your DAC does not employ SRC.<br />
      <br />
      Incidentally, SRC is condemned by some audiophiles, but it is used in the superb DAC's by Bryston and Berkeley Audio Design. Perhaps it helps that both use the SRC to perform synchronous upsampling of CD data (i.e., upsampling to 88.2 or 176.4 KHz, which is an integer multiple of the original 44.1 KHz sample rate) instead of upsampling CD's asynchronously to 96 or 192 KHz.
    1. audiozorro's Avatar
      audiozorro -
      I don't think I agree with "if your 24-bit DAC has a sample rate converter (SRC), the SRC inherently converts 16-bit data to 24-bit data before it undergoes D/A conversion, so it would be pointless to convert it to 24-bit manually".<br />
      <br />
      The recommendation is to use a digital volume control on a 24-bit file instead of a 16-bit file. This happens before any DAC, such as the Berkeley Audio DAC. As discussed previously, using the digital volume control on a 16-bit file will degrade the file before it reaches the DAC, regardless of the DAC used.
    1. Bob Stern's Avatar
      Bob Stern -
      I was thinking of a DAC that had its own digital volume control.<br />
      <br />
      You're right that the best way to implement digital volume control in computer software is to first convert 16-bit to 24-bit before applying the digital attenuation.<br />
      <br />
      Sorry for my confusion.
    1. emmodad's Avatar
      emmodad -
      can't seem to find this info anywhere, and have not yet seen an openup / teardown of the Alpha DAC to know precisely which components are used in its conversion architecture. Can anyone confirm:<br />
      <br />
      1/ if the Alpha uses a commercial D/A IC, and if so, which one (it's also possible that there may be several of the same IC used in a parallel configuration)? If not, any info on what hardware is performing the D/A conversion function, ie a module with any visible identification?<br />
      <br />
      2/ does the architecture include any obviously-visible device which could perform signal processing (FPGA, digital filter chip, DSP devices ie ADI SHARC or Blackfin, or TI or other) as a preprocessor to the D/A IC/module? Most probably this is the case, as (at mimimum) vol control and HDCD decode functionality must be performed<br />
      <br />
      3/ a DAC "box" can *accept* up to and including 192 kHz inputs, but the internal D/A conversion ICs do not necessarily operate at this sampling frequency. One example is the Benchmark DAC1, which *accepts* 32-192 kHz, but resamples any input sample rate to approx 110 kHz before conversion as part of their jitter-minimization strategy and to run the ADI D/A chip at an optimal performance-vs-sampling-frequency operating point (which was an ingenious system solution for the time when the DAC1 was designed, using D/A chips which are now of course many years old in design). Does anyone have info confirming that the Alpha DAC will actually operate at 176.4 and 192 without resampling? Does the user guide contain any info in this regard, and any performance-vs-operating-frequency characteristics? The website has only some leading- but definately marketing-speak information.<br />
      <br />
      Any pics of internals to be posted?
    1. zettelsm's Avatar
      zettelsm -
      Chris and Computer Audiophiles,<br />
      <br />
      Just a brief note to say that my Berkeley Audio Alpha DAC arrived yesterday -- the missing piece to put my high-rez music server in operation. I had a wait of a bit less than six weeks, due in part to Berkeley revising production for EIC certification.<br />
      <br />
      The Alpha has been thoroughly discussed here and in other reviews, so I won't go on and on. Suffice to say that it completely lives up to its billing. High resolution files via the Alpha are stunning -- easily the best digital playback I've had the pleasure to hear.<br />
      <br />
      There was some concern about the power supply noise of the early versions of the Alpha DAC. Evidently that has been successfully addressed in the latest DACs now shipping; my Alpha is completely silent and I've noticed no external hum from the unit.<br />
      <br />
      There is nothing original in my music server system -- all of the ideas pretty much originate from Computer Audiophile postings, and I'm very appreciative of have such a great forum to get this information out here. Keep up the good work!<br />
      <br />
      Steve Z<br />
      <br />
      Mac G4 Powebook/Thecus N5200BR Pro/iTunes > Weiss AFI1 firewire to AES > Berkeley Alpha DAC
    1. The Computer Audiophile's Avatar
      The Computer Audiophile -
      That's really great to hear Steve!
    1. riderforever's Avatar
      riderforever -
      Hi Chris,<br />
      what's the power amp used in this review? BTW, do you a think the Berkeley AlphaDAC will work fine as preamp for a Mc275?<br />
      <br />
      Thanks
    1. jonmarsh's Avatar
      jonmarsh -
      Just the end of August, after reviewing this any several other reviews, all giving the Alpha high marks, I bought one for myself, unheard- and have no regrets at all- the performance is impeccable, and has raised CD playback to levels I once thought not possible- a typical example being the Sheffield CD of the Harry James "King James Version", taken from the 1976 recording; for the first time, this disk starts to approach what the vinyl delivered, which is no mean achievement. In this regard one can say it truly demolishes anything else I've heard at $6K or less. Imaging, transient envelopes, midrange textural trueness, are essentially in a class of it's own at this price. Obviously, the recordings that benefit the most are good ones, but there are other recordings that have not been perceived in the past as all that good because they are so demanding or punishing in some respect, but are now reproduced much more realistically and satisfyingly. <br />
      <br />
      The Alpha DAC does deserve the appellation of "closer to the mic feed" and I find it money well very well spent. Mine is currently being used with a Cambridge Audio CD player as transport and with AES/EBU output from a Fireface 800 connnected to Mac Mini, at various data rates and source types. Next to investigate is a card which converts DSD to 24/192 for SACD, to see how the Alpha works with that material. <br />
      <br />
      Thanks for your review Chris.
    1. audiozorro's Avatar
      audiozorro -
      however what are you trying to accomplish when you say you need "to investigate is a card which converts DSD to 24/192 for SACD, to see how the Alpha works with that material"?<br />
      <br />
      What is your source for DSD material? Are you looking to rip or digitize SACDs?<br />
      <br />
      I had been contemplating the Korg MR-2000S to digitize vinyl at either:<br />
      <br />
      -PCM audio format: 88.2 kHz @ 24 bit, 96 kHz @ 24 bit,176.4 kHz @ 24 bit, 192 kHz @ 24 bit<br />
      <br />
      or<br />
      <br />
      -1-bit audio format: 2.8 MHz @ 1-bit DSD, 5.6 MHz @ 1-bit,DSDIFF format (extension .dff), DSF (extension .dsf),WSD (extension .wsd)<br />
      <br />
      The Korg AudioGate software can convert the DSD formats to a lower PCM audio format.<br />
      <br />
      I assume if you are looking to tap into the SACD layer this would be the legal and relatively inexpensive way to go barring the expense of needing an excellent SACD player. From the reviews and user feedback of the Korg MR-2000S, the DSDIFF result is indistinguishable from the original SACD played back on an excellent SACD player. Of course you lose a little something if you convert to PCM.
    1. zettelsm's Avatar
      zettelsm -
      I guess I have similar questions as Audiozorro -- what is your source for DSD material? I've been doing a fair bit of research and haven't found a cost-effective way of extracting the DSD information from a commercial SACD. I own an Esoteric X-03 player which can be set to output the encoded DSD stream from an SACD via iLink (firewire), however short of pro gear to decode and/or do sample rate conversion, I haven't seen anything that will let me capture the stream as a file, let alone do decoding and SRC.<br />
      <br />
      I have a Korg MR2000S, the latest firmware and software (which, BTW allows burning a DSD DVD that can be played) but AudioGate will not capture streaming PCM or DSD. 2L Recordings has about 25 minutes DSDIFF music files at their website that can be downloaded and experimented with (and AudioGate will recognize and manipulate them).<br />
      I'd love to find a source of DSD music files. Live music recording with the Korg isn't very feasible for me here in rural Montana -- there just aren't many concerts around here. <br />
      <br />
      For archiving vinyl I highly recommend using DSDIFF, either sampling frequency. DSD can be converted to high resolution PCM without the decimation issues and degradation that can occur with PCM to PCM SRC. I haven't compared the Korg/AudioGate "DSD disk" against DSD converted to 24/192 or 24/176.4 yet, but vinyl recorded to DSD and then converted to 24/192 and 24/176.4 and played via my Berkeley Alpha DAC is very, very good. I haven't developed a firm preference yet for 24/192 or 24/176.4 when converting from DSD, though I have read some theoretical and one or two practical comments that express a preference for 24/176.4 when doing SRC from DSD.<br />
      <br />
      I'd like to learn about others' experiences with DSD and DSD SRC to PCM.<br />
      <br />
      Best regards,<br />
      <br />
      Steve Z<br />
      Montana, USA
    1. StephanLJ's Avatar
      StephanLJ -
      Hi Steve et al.<br />
      I was facing similar problems since the only method of getting music off a SACD is to convert to PCM. I found the solution below and it works great for me. Output is 24/96 and with Lynx, Amarra and alpha DAC the result is more than acceptable. For recording I use Amadeus Pro.<br />
      <br />
      http://freerider.dyndns.org/anlage/HiresAudio_E.htm<br />
      <br />
      Greetings Stephan
    1. jonmarsh's Avatar
      jonmarsh -
      Yes, my interest is possible methods of SACD capture for the music server (Mac Mini). I do have a high quality SACD player already, and with Pure Vinyl it's possible to do a good capture at 24/192 and create music tracks in AIFF. Pure vinyl also has the ability to create fairly high quality 44.1 from the high rez capture and has an upsampling playback engine that can integrate with iTunes (Mac), though I haven't tried that out yet. Many things on the to-do list at this point, as I'm also finishing up a major speaker project. <br />
      <br />
      But this weekend I'm buying a used Pioneer DV-79 with the intention to install a board from these people: <br />
      <br />
      http://audiopraise.com/vanity/overview.php<br />
      <br />
      which would do a DSD to PCM conversion and output at 24/192- through SPDIF- which I will try with the Berkeley Alpha DAC. I suspect that may be the way to go, and as mentioned earlier, would use Amadeus Pro or another of the audio stream capture utilities available for the Mac to capture the incoming bit stream. Possibly a dicey concept, but I'd really like to get my SACD's on to the music system, especially the single layer ones with no hybrid RB layer which I can't back up in any form currently and can only play on the SACD player (Marantz SA-11). <br />