AVA DAC MK 5 released

Berkeley investigates the DAC MK5

The new DAC MK 5 that I’ve been working on for Audio by Van Alstine has finally been released.

I am grateful to Frank Van Alstine for giving me the room to develop the best reasonably priced DAC I know how to design. The results have so far exceeded all expectations, including my own. We all learned a lot through the process of designing this unit, which is as it should be. Rapid prototyping turned out to be instrumental in exploring a number of early electronic design alternatives. Looking forward to the reviews!

8 thoughts on “AVA DAC MK 5 released”

  1. I am looking seriously at the DVA digital preamp with DAC inside..can you tell me your thoughts in engineering and what chip being used now after the AKM fire and why that chip?

    1. I’m not sure what parts of the design AVA wants me to discuss at this point, so I can’t comment on specifics. However, I can say that the DVA Digital Preamp is using an AKM D/A converter. Immediately after the fire, we worked hard to secure a large supply of them. I also want to point out that the unit isn’t a preamp with a DAC inside. It’s digital from input to output — meaning that it’s essentially a DAC with variable volume and a slightly higher gain output filter. I plan to write up more information once the unit is finally available for sale.

    1. This post is for the AVA DAC MK5, not the new AVA Digital Preamp. I plan write up a post for the Digital Preamp when I have a spare second, but I can answer your question about volume control by stating that there are two ways to control the volume: one is via the remote control and the other is to touch the screen either in the top right quadrant (up) or lower right (down). Ditto selecting the input, except it’s on the left.

      1. Thanks,
        How is volume actually controlled, by electronic stepped attenuator with various discrete resistors, through a digital chip function in the AKM day chip, or motorized Alps pot…?
        Digital attenuation usually comes at the price of lost information at lower volumes,
        so if this is how it is done, how is the lost bits in attenuation concern addressed?

        1. The AVA Digital Preamp uses the attenuation feature built into the 32-bit AKM converter.

          Almost every recording in the universe self-dithers to 20 or fewer bits regardless of being delivered at 24 or 32 bits. Sources of the wideband noise that cause this dithering are ambient noise (even just random air motion), hiss in processing electronics, etc. This is in addition to any dithering that is deliberately added to the analog to digital conversion or subsequent processing. In other words, the noise floor of almost every recording in existence introduces dithering that is no better than 20 bits below digital full scale, or around 120dB down from 0dB. This is the best case with signals that have an analog origin. Music that is completely digitally generated can theoretically produce non-dithered 32-bit signals, but the typical delivery is 24 bits or less.

          This means with the AKM DAC there are around 12 bits of digital attenuation that can happen before digital truncation becomes an issue. This translates to about 72 dB of attenuation. The maximum attenuation prior to “mute” on the Digital Preamp is less than this, so with all practical sources, digital truncation will not be an issue.

          If you happen to be listening to a source that somehow manages 24-bits of non-dithered signal, you’re still talking about 48dB or so of attenuation before truncation becomes an issue.

          Further, any truncation that might take place under any circumstances will be around 192dB below full scale. If you set your system to an ear-crushing 140dB (120dB plus 20dB crest factor), any truncation effects will be 52dB below the lowest level sound audible to people with the most sensitive hearing.

          This leaves the analog noise that’s parts of the conversion between digital and analog domains. Signals that have been digitally attenuated will drop into the conversion process’ overall analog noise floor. But the very same thing happens with analog preamps: as the analog input is attenuated, the output’s signal to noise ratio goes down.

          So, there’s zero need to be concerned over the digital attenuation used in the AVA Digital Preamp.

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