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ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

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  • ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

    I have been exploring the realm of the "low cost DAC". This is the second DAC that I am reporting on.

    Now here we have a real contender - the "Little Bear Decoder v1.08". This is a 48kHz/96kHz spdif input DAC using a DIR9001 spdif receiver IC and the CS4398 D-to-A chip. The output is run through a 5532 op amp to provide low pass filtering and to buffer the output. The quality of the board seems to be high and good quality parts are used in critical areas.

    I performed some measurements on this DAC using an M-Audio ProFire610, ARTA/STEPS and REW. For these measurements, the signal path begins in software, goes to the 610 spdif output port, into the DAC, and then back into an analog input port of the 610. Software can then evaluate the analog input (for distortion, frequency response, etc.). This signal path also permits me to do A/B testing (after level matching) of the 610's internal DAC and the external DAC using the 610's routing software.

    I have attached the measurements I obtained. At both 48kHz and 96kHz the distortion levels are low and more or less input-level independent. I also took a spectrum of the DAC output for a 1kHz test tone, showing distortion products and the noise floor, both of which are very low. Keep in mind that the distortion spec for the analog input of the M-Audio Profile 610 that I am using to measure this DAC is 0.002% distortion (at 1kHz -1dBFS) and -108dB S/N ratio (A-weighted). Essentially the "Little Bear" DAC is approaching the measurement threshold of my equipment.

    This is an exceptional product, especially given that I purchased it for $40 including shipping to the USA. Power is supplied via a single 12-0-12 VAC input, and a transformer is included by the seller (115VAC or 230VAC primaries are available). Once you connect the transformer the unit is ready to run.

    If you are looking for an SPDIF input (only) DAC then this is really one that performs far above its price level.

    Ebay link:
    HiFi Digital to Analog Coaxial Decoder DIR9001 CS4398 96kHz 24bit DAC Converter | eBay (or search under "Decoder DIR9001 CS4398")
    Aliexpress link:
    Little Bear DAC on Aliexpress.com



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    .
    Charlie's Audio Pages: http://audio.claub.net

  • #2
    Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

    Frequency response plots and spectrum are shown below.

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    Charlie's Audio Pages: http://audio.claub.net

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    • #3
      Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

      Great deal at that price. Thanks for letting us know!

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      • #4
        Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

        Nice. Wish it had USB input so I could use it from a computer. I see the seller has a USB to coax converter but that no longer makes it so affordable.
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        • #5
          Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

          Good to see ya kicking around, Charlie...

          Second one, did I miss something? Wondering if you've considered the "Objective DAC", by that NWavguy... Or some of the cheaper ESS DAC's out there... A set of affordable DACs with the digital only miniDSP processor, would make a nice package...

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          • #6
            Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

            Nice find, I wonder if they'll make a balanced version.

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            • #7
              Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

              I might grab one and run it through an audio precision to compare our results.

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              • #8
                Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                The harmonic distortion profile is buried. Nice.

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                • #9
                  Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                  A diamond in the rough. Thanks Charlie for showing that good stuff doesn't have to cost an arm and a leg.
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                  • #10
                    Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                    The eBay seller added your post from DiyAudio to their listing.

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                    • #11
                      Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                      Originally posted by greywarden View Post
                      The eBay seller added your post from DiyAudio to their listing.
                      Ah, that's no problem. I told him that I wrote about it. I think it is a really great deal, provided you only need coax spdif input (which I do). I told him that there would probably be others who would want to buy one so he has made some more available.

                      The ironic thing is that you have to be a member and logged in at DIYaudio to see the images.
                      Charlie's Audio Pages: http://audio.claub.net

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                      • #12
                        Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                        At $35-40 it they would be a good combo to use with the MiniDSP digital 2x8 box, as it's nearly impossible to find affordable amplifiers with digital inputs and high quality DACs on-board.

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                        • #13
                          Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                          Originally posted by greywarden View Post
                          At $35-40 it they would be a good combo to use with the MiniDSP digital 2x8 box, as it's nearly impossible to find affordable amplifiers with digital inputs and high quality DACs on-board.
                          I think you mean this (the nanoDIGI):
                          http://www.minidsp.com/products/mini...nanodigi-2x8-k
                          Charlie's Audio Pages: http://audio.claub.net

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                          • #14
                            Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                            Originally posted by charlielaub View Post
                            I think you mean this (the nanoDIGI):
                            http://www.minidsp.com/products/mini...nanodigi-2x8-k
                            Yeah that one.

                            रेतुर्न तो थे स्रोत
                            return to the source
                            leviathan system thread
                            deadhorse thread
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                            in war, victory . . . in peace, vigilance . . . in death, sacrifice.

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                            • #15
                              Re: ALERT: good spdif input 24/96 DAC for only $40 (with measurements)

                              Thanks for the tip! I have about 10 different DACs on my "watch list" on eBay. Just haven't been able to pick one and pull the trigger yet. This is a helpful vote of confidence.
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