assemblage DAC-3 Instruction sheet

Construction and Operating Manual
A S S E M B L A G E
DAC -3 • DIGITAL PROCESSO R W I TH ®

Dear Assembler,
Thank you for purchasing our 24 Bit/96kHz DAC, the Assemblage DAC-3 Digital Processor kit with
HDCD®.Whether you are an experienced home audio builder, or are new to the hobby of D.I.Y. audio,
we think that you will be very pleased with the sonic results and build quality of our kit. This kit was
designed with ease of assembly and reliability in mind, clearly labeled connections, and complete
instructions.
Contents Page
Parts List..............................................................................................................................................4
Tools Required ....................................................................................................................................8
DAC-3 Functions ................................................................................................................................9
What's going on in your DAC-3 ......................................................................................................11
Wire Stripping....................................................................................................................................14
Soldering............................................................................................................................................14
Parts Layout ......................................................................................................................................18
Assembly Instructions......................................................................................................................20
Non-HDCD®Gain Reduction Selection ............................................................................................21
Input AC Line Voltage Selection ....................................................................................................24
Auto/ Mannual Digital Input Selection ............................................................................................26
System Connection ..........................................................................................................................30
Specifications....................................................................................................................................31
Future Upgrades & Options ............................................................................................................31
Guarantees and Warranty ................................................................................................................31
Schematics ........................................................................................................................................32
Warning and Disclaimer of Liability
When constructing this kit, take care that the assembly steps are followed precisely. Take extra care
when completing Step 6; if these steps are executed incorrectly, damage to the DAC-3 may result when
the unit receives power. Under no circumstances does The Parts Connection or Sonic Frontiers,
International assume liability or responsibility for injury or damages sustained in the operation or
assembly of this equipment, or for damages to any equipment connected to it. If you have any
questions regarding the assembly or set up of the DAC-3, please do not hesitate to contact us.
3

Parts List
The following list of parts are separated into groups, one for each circuit board type and chassis
assembly.This is where the parts will be installed or used. Please check the package to ensure that all
parts listed are present and accounted for.Please note that some substitutions may be made at any time
for a component value that may enhance or will maintain the original circuit operation.
On the same note, if you are planning to install the Signature Parts Upgrade kit at this same time,
take note of the parts labeled “Sig.” in this manual. Refer to the Parts Upgrade Instructions for these
replacement parts.
Parts for the Digital I/P PCB:
Printed Circuit Boards:
1 Digital I/P Board (Partially Pre-assembled)
Qty Item/Value Unit / Reference Designators
Miscellaneous
3 4-24 5/16" Philips XLR and Toslink mounting to chassis
2 4-40 Hex head 3/8" Jack screw Holds the I2S connector
5#4 Black External Tooth Lock Washers I2S, XLR and Toslink mounting to chassis
1 3/8 in x 32 Panel Nut H-P Optical Mounting
4 6-32 1/4" Zinc Screws Holds PCB to Chassis Standoff's
4

Qty Item/Value Unit / Reference Designators
4 #6 Internal Tooth lock washer Under screws
8” (Sig.) Solid Core 22awg Tinned Copper CN103, CN104 Digital Inputs
7.5” (Sig.) Teflon Clear Sleeving 18awg CN103, CN104 Digital Inputs
1 Nylon Spacer H-P Optical Mounting
Parts for the Left & Right O/P Boards:
Printed Circuit Boards
1Left & Right O/P Board Combo (Partially Pre-assembled)
Qty Item/Value Unit / Reference Designators
Output Connectors
4” (Sig.) Kimber Kable TCSS TWpr 19awg R/BK To Audio O/P jacks CN203, CN303
4 4-24 5/16" Philips XLR mounting to chassis
4 #4 Black External Tooth Lock Washers XLR mounting to chassis
8 6-32 1/4" Zinc Screws Holds PCB's to Chassis Standoff's
8#6 Internal Tooth lock washer Under screws
Parts for the Power Supply Board:
Printed Circuit Boards
1 Power Supply PCB (Bare Board)
Qty Item/Value Unit / Reference Designators
Semi-Conductors
2 74HC14 U411, U412
1 CD74HC4017E U408
1 74HC74N U410
1 74HC00 U413
1 ULN2003 U409
2 LT317AT ADJ. U401, U405
2 LT337AT ADJ. U402, U406
1 7805 + 5V Fixed Regulator U407
2 7812 + 12V Fixed Regulator U403, U404
1 LED - Coool Blue T1 LD408 Power Indicator
8 LED - Green T1 LD401-407, LD411, Lock, Phase, Digi in's
3LED - Red T1 LD409, LD410, LD412 Mute, De-Emph, HDCD®
11 1N4002 D417-427
16 (Sig.) SF4002 or HFA4002 D401-416
4 1N4148 D428-430, (D431 under pcb as noted in text)
Capacitors - Electrolytic (Radial)
11µF/50V C459 under pcb as noted in text
12 47µF/25V C435-444, C446, C453
12 3300µF/35V C417-428
5

Qty Item/Value Unit / Reference Designators
Capacitors
1 120pF (C460 under pcb as noted in text)
16 10nF C401-416
17 100nF C429-434, C445, C447-452, C455-458
1 220nF C454
Parts for the Power Supply Board: (Continued)
Qty Item/Value Unit / Reference Designators
Resistors - 1/4 Metal Film 1%
1100R R427
4 243R R401, R404, R409, R412
3 300R R405, R407, R408
2 626R R406, R420
1 1K62 R431(under pcb as noted in text)
1 1K97 R419
4 2K64 or 2K67 R402, R403, R410, R411
1 3K97 R421
1 4K32 R429
3 16K9 R414, R416, R418
6 100K R413, R415, R417, R422, R423, R426
31M5 R424, R425, (R430 under pcb as noted in text)
Switches
3 Right Angle, Tact PCB Mount SW401, SW402, SW403 I/P, Phase, Mute
1 DPST Push On-Push Off SW404 Main Power Switch
Transformers
1 15V 25VA Toroidal TR402
2 18V 25VA Toroidal TR401, TR403
Connections
13 Pin Male Header Single Inline J401
12 Pin Female Shorting Jumper J401 Selects Auto/Manual I/P Scan
310 Pin Ribbon w/1 connector CN401-3 Power to other Brd's
110 Pin Male Dual Inline CN404 Cable to Digital I/P PCB
1 10 Cond. 1 foot Flat Ribbon CN404 to CN106 connection
Cable w/connectors
Miscellaneous
6 Heat Sink Single TO-220 U401-6 Voltage Reg's
4 Teflon Shoulder Washer U401, U402, U405, U406
6 Silpads U401-6 Voltage Reg's
1800 mA, & 400mA SLO BLO Fuses F101 (only one used, see text)
1 pr. 5x20 Fuse Clips PCB M't. F101
6

Qty Item/Value Unit / Reference Designators
1 Fuse Cover Boot F101
1 in Heat Shrink Tubing R431
Hardware
64-40 X 3/8" philips PH SS Screws U401-6 Heatsinks
6 #4 Kepnuts U401-6 Heatsinks
9 6-32 1/4" Zinc Screws Holds PCB to Chassis Standoff's
9#6 External Tooth lock washer Under Screws
Qty Item/Value Unit / Reference Designators
Main Chassis Components:
1 Main Chassis
1 Main Chassis Top Cover
1 Front Panel - Aluminum
3 Tact Button Scan I/P, Phase, and Mute
1 Plunger Button For Power Switch
Chassis Mounted Hardware
1 (Sig.) RCA Female Jack - RED CN303 Audio O/P Right
1 (Sig.) RCA Female Jack - WHITE CN203 Audio O/P Left
1 (Sig.) RCA Female Jack - BLACK CN104 S/PDIF I/P
1 BNC Male, Chassis Mt. 75 Ohm CN103 S/PDIF I/P
1 IEC Filtered Socket AC Input
4 E. A. R. - Mounting Feet Chassis Feet
Chassis Assembly Hardware
14 4-40 1/4" Blk Counter Sunk Holds Top Cover
24-40 X 3/8" Philips PH SS - Blk Holds IEC to chassis
2 #4 External Tooth lock washer - Blk Under IEC Screws
2 #4 Kepnuts Holds IEC to chassis
1 6-32 1/4" Zinc Screws IEC AC Safety Ground to chassis
4 6-32 1/2" Screws Feet to Chassis
3 M4 x 6 Screws Holds Transformers
3 M4 Washers Holds Transformers
1 #6 3/4" Solder Lug IEC AC Safety Ground to chassis
4 #6 Flat washer Feet
2 #10-32 Kepnuts Holds Front Panel to chassis
Miscellaneous
10 ft WonderSolderTM Silver Solder
1 ft Solder-wick
1 Detachable AC power cord
1Construction and Operation Manual (If you have made it this far, chances are it's here!)
1 Warranty Card - Remember to return this card.
7

Tools Required
In addition to the parts supplied in the kit, you will need any or all of the following tools to complete
the construction of the DAC-3 kit.
1 Solder Sucker
1 Pencil tip soldering iron of good quality (900oF tip temperature max.)
1 #1 Philips screwdriver
1 #0 Philips screwdriver
110mm wrench, nutdriver or ratchet (3/8" will also work)
1 12mm wrench, nutdriver or ratchet (1/2" will also work)
1 14mm wrench, nutdriver or ratchet (9/16" will also work)
16" crescent wrench (adjustable wrench)
1 Pair of fine tipped needle nosed electronics pliers
1 Pair of regular needle nosed pliers
1 Pair of regular pliers
1 Wire stripper or hobby-knife (If you trust yourself with your fingers!)
1Wire side cutters
1 Ruler/Scale (not shown)
8

DAC-3 Functions :
A - Source Selector Tactile Button
This button will activate a manual or automatic
advancement to the next digital source input.(See page
25 for setup.)
B - Source Selector LED's
These LED's indicate which digital source input is
currently selected - either the I2S,ST-Optical,TOSLINK-
Optical, AES/EBU, Coaxial-BNC, or Coaxial-RCA.
C - Phase Tactile Button
Reverses the absolute polarity of the Analog Output
Signals.
NOTE ON PHASE SELECTION:
The phase inverts the absolute polarity of the analog
output (A positive signal becomes a negative signal).
This can be used to compensate for recordings with
inverted polarity. The correct phase for a recording can
be found by playing a CD in both phase positions.When
absolute polarity is correct the music will be more
precise, with a wider, deeper soundstage.
D - Phase LED
This LED will indicate the currently selected phase
polarity. When lit, the absolute phase is inverted 180
degrees.
E - Power LED
This coool blue LED will light when the DAC-3 is
plugged in and switched on while receiving AC power.
F - Mute LED
Muted conditions of all the audio O/P's are indicated by
this LED.While lit this indicates that the audio O/P's are
muted. This Mute LED comes on during digital I/P
scanning, or when no active digital source is connected
and received by the DAC-3, (In both cases, no Lock
condition also applies.)
G - Mute Tactile Button
Depressing this button will active the muting relays for
each audio channel and signal phases, allowing no
audio from any of the audio O/P's as indicated by the
Mute LED above.
H - De-emphasis LED
This LED lights when a digital source is recorded with
the standard CD pre-emphasis of 50/15 microseconds.
(This LED rarely comes on.)
I - Lock LED
This LED indicates when a signal from a digital source,
with a sampling rate of 32kHz to 96kHz, is being
properly received.
G - HDCD®LED
Lights when an HDCD®encoded Disc is played into the
DAC-3.
H - Power Switch Button
The switch is a push-on push-off type button.The power
to the DAC-3 is completely turned off while the switch is
in the out position.
BA C HGIHGFED
9

Connection Functions
I - AC Power Cord Socket
Plug in the female end of the detachable power cord
here.
J - XLR - Audio Output Right Channel
Balanced XLR Output connects to a balanced right
channel line input on a preamplifier, integrated amplifier,
or receiver.
K - RCA - Audio Output Right Channel
Un-balanced RCA Output connects to an un-balanced
right channel line input on a preamplifier, integrated
amplifier, or receiver.
L - S/PDIF Coaxial - RCA Input
Plug in a digital source that has a Coaxial digital output
with RCA connectors.
M - S/PDIF Coaxial - BNC Input
Plug in a digital source that has a Coaxial digital output
with BNC connectors.(75 Ohm characteristic impedance).
N - Optical-ST Digital Input
Plug in a digital source that has a ST-Optical digital
output here.
O - Optical-Toslink Digital Input
Plug in a digital source that has a Toslink Optical digital
output here.
P - AES/EBU Digital Input
Plug in a digital source that has an AES/EBU digital
output with XLR connectors. (110 Ohm characteristic
impedance).
Q - I2S Digital Input
Plug in a digital source that has a I2S digital output here.
(13W3 connector).
R - RCA - Audio Output Left Channel
Un-balanced RCA Output connects to an un-balanced
left channel line input on a preamplifier, integrated
amplifier, or receiver.
S - XLR - Audio Output Left Channel
Balanced XLR Output connects to a balanced left
channel line input on a preamplifier, integrated amplifier,
or receiver.
IJKN QPO
L M
RS
10

What’s going on in your DAC-3
Pacific Microsonics
PMD-100 Digital Filter
and HDCD®Decoder
IEC AC Input Filter -
filters out high frequency
components in AC line
voltage - also prevents
digital noise from getting
out to the AC line
Potted Dual
Secondary Toroidal
Power Transformer -
for lower emitted magnetic
field and noise
Power Supply Filter
Caps - to smooth raw
DC voltage
Auto / Manual Digital
Input Selector
Crystal CS8414 Input
Receiver-reclocks incoming
digital signal
Left DAC Output PCB
4 layer
Right DAC Output PCB
4 layer
Digital Input PCB
4 layer
DC Servo stage
nulls out DC offset of
I/V converter
Output Muting Relay
(Shunt configuration)
Non-HDCD gain
reduction disable/enable
jumper
Dual ISO-150 Isolate
the digital ground noise
from the DAC output
boards
AC input voltage
selection jumpers
Power Supply PCB
2 layer
LT1357 I/V Converters -
converts current
output of DACs to
a voltage output
24 Bit Resolution Burr-Brown
PCM 1704 DACs (2 per channel) -
converts digital data stream into
analog wave form by quantizing each
sample into a discrete AC current