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Electronics Module Info & Upgrades
Max Module
Hooking Up Your Home Amp
USB Input
The Home Module
This little blue module contains all the electron-
ics for a Home Headphone Amp. There are two
4-layer circuit boards (one each for the left and
right channel) that are connected with a series
of header pins used to solder the module to the
main circuit board. This module is designed to
sound great without going up the ridiculously
steep part of the diminishing returns curve. It
uses OPA2134 op-amps for the internal input
buffer, crossfeed, summer, and power amp volt-
age gain stage. The output current amplifi er is our version of the highly regarded Dia-
mond Buffer discrete transistor design by Walt Jung. All these active circuits are forced
in to class “A” bias with constant current sources. Resistors are 1% metal thin fi lm, and
caps in the signal chain are polyphenylenesulfi de (poly fi lm). The sound of this module
is not only well balanced and punchy, it’s also liquid and integrated. This is a sweet
listen. The Home Amp and Home Balanced Amp can be upgraded with Max modules.
This is a tricky maneuver and must be executed with exceeding care. Only those with
the trickest of gear should bother as these babies are pricy almost beyond reason;
every one else should just enjoy the lovely sound of getting it right between your ears
in a less spendy module. But the Max Modules are the real deal, and easily let you tell
the difference between a $3000 and $12000 CD player.
This little gold and black module is the real
deal. Tiny chips that cost $15 bucks apiece,
0.1% metal fi lm resistors, and polyphen-
ylenesulfi de (poly fi lm) caps are silver sol-
dered to 2 oz. gold coated copper traces
which blur in a glittering haze over black sol-
der masked four layer circuit board. Speak-
ing of circuit board, this is the fi rst time
we have increased the sized of our module
circuit board. Fear not, for it is still pin for pin compatible with older Home and Max
units. But the circuit boards must be mounted on edge for better heat dissipation.
The Max Module uses what many audiophiles insist is the best audio op-amp made,
the OPA627, for the internal input buffer, crossfeed, summer, and power amp voltage
gain stage. The output current amplifi er is our version of the highly regarded Diamond
Buffer discrete transistor design by Walt Jung. All active stages are forced heavily into
class-A bias with coinstant current sources. Writing this copy we realized the benefi t
statement of the Max module is the features statement. The quality of the entire build
of this module is out of this world, and when coupled with the fi nest of headphones
and the fi nest of front ends, the results are transcendent bliss.
Optical Input
Coaxial Input
Analog Input
...Using the Digital-to-Analog Converter Option
...Using the Analog Connections
1. Select ‘digital’ on the digital/analog selector
switch on the back of the unit
2. Select ‘USB’ on the digital selector switch on
the back of the unit
3. plug your USB cable into the back of the am-
plifi er
4. plug the other end of your USB cable into any
USB jack on your computer or player.
It is a good idea to turn your units off while connecting equipment.
ALWAYS turn your units off with the volume all the way down before plugging and unplugging your
headphones from the jacks.
Amplifi er DAC,
USB
Computer, USB
RCA analog
inputs
amplifi er DAC,
coaxial input
CD player,
coaxial output
Amplifi er DAC,
optical input
CD player,
optical output
CD player,
analog
outputs
Home Module
You will need an RCA cable with right and left
terminations on both ends.
1. Select ‘analog’ on the digital/analog selector
switch on the back of the unit
3. plug your RCA cables into the back of the am-
plifi er using analog input set ‘1’ or ‘2’.
4. Select the corresponding set number of the
analog input select switch
5. plug the other end of your RCA cable into the
analog output of your CD player.
1. Select ‘digital’ on the digital/analog selector
switch on the back of the unit
2. Select ‘optical’ on the digital selector switch
on the back of the unit
3. plug your optical cable into the back of the
amplifi er.
4. plug the other end of your optical cable into
the optical output of your player.
1. Select ‘digital’ on the digital/analog selector
switch on the back of the unit
2. Select ‘coaxial’ on the digital selector switch
on the back of the unit
3. plug your coaxial able into the back of the
amplifi er.
4. plug the other end of your coaxial cable into
the coaxial output of your player.
The Max Module Upgrade
