K & K Audio Extreme RAKK Mark III User manual

RAKK dac
Ralei
g
h Audio
K&K Audio
RAKK dac
Mark III
Extreme RAKK dac
Assembly Manual
Version 1.1 © 2010 Raleigh Audio

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This completed Extreme RAKK dac has a silver face plate and knobs. A black faceplate and knobs is available.
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1

GeneralInformation
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The Extreme RAKK dac is a semi-custom kit, which means that several standard offerings can
be combined in different ways. You can choose to have an optional volume control and optional
select switch. You can choose to have one to four inputs which may be a mix of SPDIF,
AES/EBU, USB or I2S. These are covered in this manual although all of the possible
combinations are not shown. However, those things not shown can be easily inferred from other
things that are shown. Some interfaces, such as TOSLINK, are not included in this manual but
are available as special-order items.
This kit is relatively straightforward to build, but assumes some prior skill with a soldering iron
and some knowledge of electronic components and assembly.
Kit version
Use this manual with the Extreme RAKK dac Mark III
•Use the applicable on-line manuals for component sub-assemblies.
Required Tools and Supplies
150 to 250 Watt soldering gun
35 to 50 Watt soldering iron
Phillips (cross point) screwdriver
Volt-Ohm-Milliamp Meter
Potentiometer adjustment tool (supplied)
1/16” hex (Allen) wrench (supplied)
5/64” hex (Allen) wrench (supplied)
1.5mm. hex (Allen) wrench (supplied)
2.5mm. hex (Allen) wrench (supplied)
1/4”, 5/16”, 1/2”, 9/16” open-end wrenches
Diagonal cutting pliers
Long-nose pliers
Wire stripper
Solder
Use the soldering gun only to solder the heatsink pins.
Use the soldering iron for all other components.
Support
RAKK dac and its associated components are produced through the joint cooperation of K&K
Audio and Raleigh Audio. You may contact us with questions on constructing this kit by sending
an e-mail message to [email protected] or [email protected]
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Warnings and Cautions
Warning — a high voltage power supply (200VDC) is required to make the kit operate properly.
These voltages can be lethal. If you are not familiar with safe techniques for completing the
installation of this kit with a high voltage power supply, then you should seek someone who is
qualified to help you construct this kit safely. If you wish to review safe practice, consult the
ARRL Handbook for Radio Amateurs (www.arrl.org or often at used book stores), which has a
section on high voltage safety. Although they are usually referring to 1000v+, the techniques are
still applicable. As the purchaser, you assume responsibility for safe assembly, testing, and
application of this kit.
Caution – Use only solder that is intended for electrical circuits. Do not use acid or corrosive
flux of any kind.
Caution – Any MOSFET is subject to damage by static electricity. Thus, the MOSFETs need
special care and handling especially when the relative humidity is low. Make sure to discharge
any static electrical charge from your body before handling a MOSFET. You can discharge your
body by touching a water faucet or grounded electrical appliance.
Soldering Notes
To a large extent, the success of your kit-building endeavor depends on your ability to solder
properly. Aside from experience, there are two pretty important factors in this success. The first
is the soldering equipment. I recommend using a temperature controlled soldering station,
although any good soldering iron of 40 watts or greater will do. There are many soldering
stations on the market; I have had good experience with the moderately priced Hakko Model
936. If you do have or purchase a soldering station, or even use your existing soldering iron, I
have found a chisel style tip of about 2mm-2.5mm width to be the most useful. You can use the
flat part for large solder joints and the corner for small solder joints. The second factor is the
selection of the solder you will use. The PC boards and most of the electrical components in the
kit are lead-free, as the movement in the EU has forced manufacturers to remove the lead (and
other dangerous heavy metals) from their products. Decent (notice, I didn’t write “good”) lead-
free solder exists, such as Cardas Tri-Eutectic, but it is not so easy to use unless you have some
soldering experience. Lead-free solder tends to melt in a sluggish way and the resulting solder
joints are not the customary shiny silver color, so it’s difficult to avoid “cold” solder joints
without experience. It’s up to you to decide what to use. Choose based on your experience. I
use Cardas Quad Eutectic and can recommend it without reservation; however other high quality
solders may work just as well. Take care in handling electronic solder as most of it still contains
a significant quantity of lead. Wash your hands thoroughly after construction sessions and keep
all kit materials well out of the reach of small children.
Even though there is a “component side” and solder side” to the board, your might find it more
convenient to solder the leaded components from the component side.
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TableofContents
General Information ......................................................................................................................................................2
Table of Contents...........................................................................................................................................................4
Assembly Instructions ...................................................................................................................................................5
Pre-wire the printed circuit boards ................................................................................................................................6
Pre-wire the Power Output Module (for RAKK dac) ................................................................................................7
Pre-wire the Power Output Module (for I2S or USB Adapter) .................................................................................7
Pre-wire the Power Boost Module.............................................................................................................................7
Pre-wire the Active Output........................................................................................................................................8
Pre-wire the RAKK dac...........................................................................................................................................10
Pre-wire the USB to I2S Adapter (if used)..............................................................................................................11
Pre-wire the I2S Interface Adapter (if used)............................................................................................................12
Pre-assemble the USB Adapter or I2S Adapter with the RAKK dac ......................................................................13
Pre-wire the Power Transformer .................................................................................................................................14
Panel Preparation.........................................................................................................................................................16
Bottom Panel Preparation ........................................................................................................................................16
Top Panel Preparation .............................................................................................................................................17
Back Panel Preparation............................................................................................................................................17
Side Panel Preparation.............................................................................................................................................18
Front Panel Preparation ...........................................................................................................................................18
Panel Assembly ...........................................................................................................................................................19
Bottom Panel Assembly ..........................................................................................................................................19
Back Panel Assembly ..............................................................................................................................................27
Front Panel Assembly..............................................................................................................................................33
Final Assembly and Wiring.........................................................................................................................................34
Wire the Bottom Panel to the Back Panel................................................................................................................34
Wire the Bottom Panel to the Front Panel ...............................................................................................................38
Assemble the Panels ................................................................................................................................................44
Install Internal Cables..............................................................................................................................................44
Final Adjustments........................................................................................................................................................49
Adjust the Constant Current Sources.......................................................................................................................49
Adjust the Front Panel LEDs...................................................................................................................................50
Final Assembly............................................................................................................................................................50
Parts List......................................................................................................................................................................51
Circuit kits ...............................................................................................................................................................51
Front Panel Options .................................................................................................................................................51
Input Options ...........................................................................................................................................................52
Extreme Kit Contents ..............................................................................................................................................53
Document version history............................................................................................................................................56
4

AssemblyInstructions
Before you start, read through the instructions completely to the end.
Inventory the kit contents to become familiar with the parts and to make sure you have
everything.
The assembly sequence is as follows:
1. Assemble all of the printed circuit boards
2. Pre-wire the printed circuit boards
3. Pre-wire the power transformer
4. Install PC boards and the power transformer on the bottom panel
5. Assemble the components on the back panel
6. Assemble the components on the front panel
7. Assemble the panels
8. Wire everything together
There are two sizes of stranded wire provided with the kit, #22 and #20. The larger diameter #20
is used for power and high voltage. The smaller diameter #22 is used for signal and low voltage.
Where a wire is to be connected to a PC board, prepare the end by stripping ⅛” insulation and tin
the bare wire. For other connections, strip ¼” and tin the end. Where a twisted-pair is called for,
provide about four or five twists per inch. Twisting wires together will shrink their length
slightly so you need to take this into account. With a very few exceptions, which are explicit,
insert the wire into the pad from the bottom, or solder side, of the board. Wires should be
dressed neatly as close to the bottom of the enclosure as possible.
Assemble the Printed Circuit Boards
Depending upon the feature mix that you have chosen, the boards that you will assemble will
vary. In all cases your project will include a RAKK dac, an Active Differential Output board, a
Low-Voltage Power System Output Module and Power Boost Module. You may also have
chosen to have a USB adapter, or an I2S adapter and their associated power Output Modules.
While assembly of all of the boards is straight-forward, the Active Differential Output is the
most complex. Therefore, I recommend that you leave that board until you have assembled all of
the other boards.
The assembly manuals for the boards include installation instructions that you will not use.
Rather than using those general instructions, you will follow the specific installation
instructions contained in this manual.
Referring to the applicable on-line manuals, assemble the boards now.
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5

Prewiretheprintedcircuitboards
In the following steps, the wires should be inserted into the solder side of the board. “Preparing a
wire” means to strip ⅛” of insulation from both ends of the wire and tin the ends.
Because each wire has a “from” end and “to” end, and only one end is pre-wired, some pads are
not wired in this section. A signal line or a function will likely have the same name on the
“from” end as it does on the “to” end, therefore don’t just go by the name when you install the
wire. Rather, check that you are installing it on the proper board.
Basically there are two ways to make a twisted pair or a multi-wire cable. The quick and easy
way is to use an electric drill. So if you have a variable speed drill, all you have to do is to put
the wires together in the drill chuck and turn on the drill. It might take a little practice to get the
tension and speed right but once you get the knack, it is quick and easy to do. If you don’t have a
drill handy, the old-fashioned way of manually twisting the wires works fine. I have described
how I do it here. To make a multi-wire cable, first make a twisted pair and then wrap a third
wire around the twisted pair following the lay of one of the wires. Then stretch this new wire like
you did the others. Follow with a fourth and fifth wire as needed.
About 5% shrinkage occurs when making a twisted pair. So for example, if you wanted a 10”
long twisted pair, you would make it from two 10½” wires. It would be better to err a little on the
long side because you can always trim the length when you install the twisted pair.
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6

PrewirethePowerOutputModule(forRAKKdac)
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If you have two Power Output modules, this is the one that will be used to power the RAKK dac.
Prepare a 3” #22 red/black twisted pair.
•Connect the red wire to the 12VDC Output “+” pad.
•Connect the black wire to the 12VDC Output “-” pad.
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PrewirethePowerOutputModule(forI2SorUSBAdapter)
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Skip this section if you do not have a USB or I2S Adapter.
Prepare a 17” #22 red/black twisted pair.
•Connect the red wire to the 12VDC Output “+” pad.
•Connect the black wire to the 12VDC Output “-” pad.
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PrewirethePowerBoostModule
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1. Prepare a 13” #22 red/black twisted pair.
•Connect the red wire to the 12VDC Output “+” pad.
•Connect the black wire to the 12VDC Output “-” pad.
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2. Prepare a 5¼” #22 red/black twisted pair.
•Connect the red wire to the LED “A” pad.
•Connect the black wire to the LED “C” pad.
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7

PrewiretheActiveOutput
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Wire the Input Select on the Active Output
1. Connect a jumper wire between the two Input Select pads.
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Wire the Volume Control on the Active Output
(skip this section if you do not have a volume control)
2. Prepare a 5½” #22 blue/black twisted pair.
•Connect the blue wire to the volume control “L+” pad.
•Connect the black wire to the volume control “L-” pad.
3. Prepare a 4½” #22 orange/black twisted pair.
•Connect the orange wire to the volume control “R+” pad.
•Connect the black wire to the volume control “R-” pad.
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Wire the “From RAKK dac” inputs on the Active Output
4. Prepare a 4” #22 black wire.
•Connect it to the “REF” pad.
5. Prepare a 4” #22 orange/black twisted pair.
•Connect the orange wire to the “R+” pad.
•Connect the black wire to the “R-” pad.
6. Prepare a 4” #22 blue/black twisted pair.
•Connect the blue wire to the “L+” pad.
•Connect the black wire to the “L-” pad.
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The Line Input pads are not used.
The external mute pads are not used. 
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