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The Digital-Analog Converter Option
Home DAC & Upgrades
The Home DAC
The Home DAC starts to become a very serious digital to analog converter: not only
does it use the flagship Cirrus Logic CS4398 DAC, it also uses the spendy---but oh so
sweet sounding---Burr-Brown OPA627 op-amps in class “A” bias as the output de-
vices. The result is the kind of liquid clarity found in multi-thousand dollar high-end
CD players.
To go along with the previously mentioned class “A” biased OPA627s, only metal thin
film resistors and polyphenylenesulfide (poly film) capacitors are used in the audio
circuits. Three low-noise, ul-
tra-low dropout power supply
regulators isolate the various
digital, analog, and mixed sig-
nal circuits. This DAC is also
available in a balanced ver-
sion for the Balanced Home
Amp with two complete con-
verter sections, one for the
normal and one for the inverted
audio signal.
8. Coaxial Input
The coaxial input is your typical coaxial connector. We rec-
ommend using a 75 ohm digital cable when using the coaxial input.
9. Digital Input Selector
When using the DAC, the digital input selector
allows you to choose which digital input you would like to listen to.
10. USB Input
The USB input gets its signal from a computer: laptop or
desktop; PC, Mac, or Unix.
11. Source Selector
When using the DAC, you will need to choose whether
you are using a digital input or an analog input. The source selector switch al-
lows you to have both digital and analog sources connected at the same time,
and you may change between the two with a simple flip of this switch.
12. Optical Input
The optical input is your typical Toslink connector. You
get this input signal from the optical output of your player. Not so many porta-
ble audio players have optical outputs anymore, but many portable DVD play-
ers and some hard disk drive players do. Of course, you can get this signal from
many pieces of home audio equipment.
11.
source selector
12.
optical input
8.
coaxial input
9.
digital input selector
When purchasing the Home Amp, you have the option of including a DAC. If
you did not purchase the DAC option with your amp initially, you can have
this upgrade performed at a later date.
When music is stored on a CD, digital audio tape, or hard drive, it is stored as
a series of numbers. Each number represents the voltage of the audio signal
at a particular point in time. String 44,000 voltage points together and you get
one second of music signal. (The audio geeks in the crowd will point out that
96,000 and 192,000 numbers per second are also common sampling rates.)
The job of a DAC (digital to analog converter) is to convert the string of numbers
into an analog signal that can be amplified to drive your headphones.
10.
USB input
Home DAC
What is a Digital to Analog Converter?
The Max DAC Upgrade
The Max DAC is a work of digital upsampling art in gold and black. These four layer
gold coated, double copper circuit boards are covered edge to edge with the best parts
money can buy, and right in the middle of it an Analog Devices AD1896 192 kHz Stereo
Asynchronous Sample Rate Converter. WHAT!? Simply a screaming gizmo that upcon-
verts any digital signal into an ultra high speed, high resolution digital signal without
relying on the incoming clock, and then down converts it into the slower 192 kHz word
stream while interpolating (to get rid of the “digital” haze) and reclocking (to get rid of
jitter) before sending the data off to the DACs. The result?
This DAC is good. Sure, a $10,000 CD player is better, but just. Tweaky ground plane
adjustments are made for stability and speed on that gold coated circuit board we
mentioned earlier. Quality components don’t end there, though, only metal thin film
resistors and polyphenylenesulfide (poly film) capacitors are used in the audio circuits.
Three low-noise, ultra-low
dropout power supply regula-
tors isolate the various digi-
tal, analog, and mixed signal
circuits. The Balanced Max
DAC features two complete
converter sections, one for
the normal and one for the
inverted audio signal.
Max DAC
Upon purchase of your Home amp, You can choose the Home DAC Module or
upgrade to the Max DAC.
