Hirsch

Your notes about the volume control not being very useful probably means that
the gain has some minimum fixed gain for the ADC path...sort of makes sense with
standard levels coming in earlier from a MIC. I'm sure that low levels can be
acommodated. The neat thing about the input jacks is that they are actually
stereo capable but wired as mono. I've just figured out that most headphones in
the 32 ohm range can take about 100mW maximum signal (or about a 1.8V rms ). I
can definitely reconfigure the existing pots to vary a 0 dBFS signal between a
whisper to about maybe 5V rms max that is needed by some 600 ohm based
headphones.

PeAK





--- In DIOmods@yahoogroups.com, "Hugo Z. Hackenbush" <rufustfirefly@m...> wrote:
>
> ----- Original Message -----
> From: "PeAK" <peakrchau@y...>
> To: <DIOmods@yahoogroups.com>
> Sent: Monday, March 07, 2005 9:38 AM
> Subject: [DIOmods] Modifying the "ART DI/O" as a tube head amp
>
>
> Interesting idea. As is, you can use analog inputs, hook the digital input
> to the digital output, and use an RCA to phone plug adapter on the analog
> outputs, and the core unit is already there. The problem is that the stock
> DI/O's gain does not go low enough to be practical to use with headphones
> when used that way. Drop the gain somewhere along the line, and the
> headphone amp is already there. If you can put a variable gain attenuator
> somewhere after the digital board, it would allow the DI/O to work as a
> headphone amp with either analog or digital input. If you use the ADC
> section as the amplifier, then it will work with digital input only. Nice
> in a DAC, but limiting in a headphone amp.
>
> Hirsch