Sound Skulptor MP 512 User manual

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Document revision 2.1 – Last modification : 11/09/20
MP 12 Assembly guide
Safety warning
The kits are main powered and use potentially lethal voltages. Under no circumstance should someone undertake the
realisation of a kit unless he has full knowledge about safely handling main powered devices.
Please read the “DIY guide” before beginning.
Print or open the following documents :
•MP 12 Schematics
•MP 12 Components layout
•MP 12 Parts list
•MP 12 Test guide
Follow this guide from item number 1 till the end, in this order. The assembly order is based on components height, from
low to high profile, in order to ease the soldering process : The component you are soldering is always taller than the
previously assembled ones and it is pressing nicely against the work area foam.
Soldering
All the PCB holes are metallized. It means the connection between the top and bottom pads is already
done. The parts must be soldered only from below (unless differently stated).
Use only small diameter solder, 0. or 0.7 mm, 1mm maximum. Use the minimum possible amount of
solder. Bad joints are almost always caused by too much solder.
Cut the component leads and pins totally flush with the PCB after soldering. A too long tail could create
an electric connection with the side plate.
Here are two excellent introduction to soldering videos:
http://www.eevblog.com/2011/06/19/eevblog-180-soldering-tutorial-part-1-tools/
http://www.eevblog.com/2011/07/02/eevblog-183-soldering-tutorial-part-2/
MP 12 Main board Assembly guide
1. PCB split
Split the PCB into 3 parts along the
grooves (red lines on the picture).
Use extra thin sandpaper to polish
all the rough sides.
2. DOA Pin Sockets
Solder the 7 pin sockets for the DOA. Solder one at a time.
Depending on the tin thickness on the PCB you may have to press
quite hard to fit them into their hole.
The correct positioning of the sockets is important for easy
insertion of the DOA.
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Document revision 2.1 – Last modification : 11/09/20
MP 12 Main board Assembly guide
3. Diodes
Add D1 to D6, D8, D9. Use a lead forming tool to bend the leads at 0.4”.
Warning : Make sure to respect the direction of the diodes which is marked by a ring on the component
and a double line on the PCB marking.
4. Resistors
The best method to select and install the resistors is the following:
1. pick a row of resistors in the resistors bag,
2. Measure one of the resistors with your DMM,
3. Look up the parts-list PDF for the closest value,
4. Check the color code and quantity for confirmation,
. Use the search function on the Layout PDF page with the resistor value: All the corresponding
resistors are highlighted,
6. Insert and solder.
(You can use the same method later, for the capacitors)
Add R1 to R1 , R19 to R22, R24 to R40. The resistors marked NC in the parts-list should not be
installed.
Control the resistor values with a digital multimeter. Bend the leads at 0.4” with a lead forming tool.
Warning : It is important to check the resistors value with a DMM because the color code can sometimes
be ambiguous. For example 1K (brown-black-black-brown-brown) can be confused with 110R (brown-
brown-black-black-brown).
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Document revision 2.1 – Last modification : 11/09/20
MP 12 Main board Assembly guide
. Led
Bend the leads of D7
right angle at 6mm from
the body taking care of
the anode position (the
longest lead).Insert from
the PCB bottom and
solder with the LED body lined up with the PCB surface.
Warning : it is easy to bend the leads in the wrong direction !
6. Integrated Circuit
Insert U2 and solder. You will need to bend the pins slightly inwards before inserting.
Warning : Make sure to respect the IC direction, marked by a notch. Do not use a socket because it
would be to high for the DI board.
7. Relays
Add RLY1 & RLY2. Eight pins only are soldered.
Warning : Make sure to respect the direction of the relays which is marked by a white line on the relay
and on the PCB marking.
8. Ceramic capacitors
Add C1, C2, C3, C , C8, C17, C18, C19.
9. Film capacitors
Add C10
10. Jumper header
Solder the jumper header JMP1. Solder one pin first, check verticality, then solder the other pin.
11. Test pins
Solder the 6 test pins TP1, TP2, TP4, V+, V- and 0V.
12. Connector
Solder the connector socket CN1. Solder one pin first, check verticality, then solder the other pins.
13. Inductor
Add L1. This inductor is installed vertically.
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Document revision 2.1 – Last modification : 11/09/20
MP 12 Main board Assembly guide
14. Small electrolytic capacitors
Add C4, C6, C7, C20, C21.
Solder one lead first, adjust verticality then solder the second lead.
Warning : The +lead must go into the +hole. Do not reverse (they may explode !)
1 . Switches
Add SW1, SW2 and SW3. The position of the switches is critical for a good front-plate matching. They
must sit flat on the PCB. Press firmly the switch on the PCB and solder one of the front pins (housing).
Check verticality and horizontality. Then solder the other pins.
16. Potentiometers P1 & P2
Place the bracket on the potentiometer bushing, and attach it with the lock washer and nut. Tighten.
Insert potentiometer and bracket into the PCB holes. Solder the central potentiometer pin. Now check
that the potentiometer shaft is perfectly parallel to the board. Then solder the other pins.
Warning : A good potentiometer position is very important for a good match with the front panel.
17. Input transformer
Pin 1 on the transformer is identified by a red dot. Insert the transformer, pin 1 into hole number 1.
Leave a small gap under the transformer in order that the case doesn't touch the PCB pads.
Start soldering 2 opposite pins, check the position, adjust if necessary then solder the other pins.
Warning : Double check the pin 1 position because this transformer can be mounted backwards!
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Document revision 2.1 – Last modification : 11/09/20
MP 12 Main board Assembly guide
18. Output transformer
The transformer is mounted using two 2 mm M3 screws inserted
from the back of the board. Two metal washers are fitted on each
screw to prevent the transformer touching the PCB. One more
washer is used before the nut to protect the lams.
Shorten the leads to the necessary length, around 6 cm. Strip on
mm, insert in the color corresponding pad hole and solder. Cut
flush.
19. Large electrolytics
Add C9 and C1 .
These capacitors are bipolar so they can be inserted in any direction.
20. Visual check
At this point, brush the solder side with a hard tooth brush to remove any remaining solder bits.
Make a full visual check. When everything looks correct, proceed with the frame assembly.
21. Frame assembly
Attach the side panel to the front
plate with two M3x6 black
countersunk screws.
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Nut
Transformer
PCB
1 Washer
2 Washers

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Document revision 2.1 – Last modification : 11/09/20
MP 12 Main board Assembly guide
22. PCB mounting
Put the PCB in place, switches and pots going through the front panel. Watch out for the LED position.
Attach the PCB with 4 M3x2 mm spacers and 4 shake-proof washers.
23. Knobs
Attach the 2 knobs.
24. Test
Your MP 12 is now ready for test. Please follow instructions in the “MP 12 Test” document.
DI board Assembly guide
1. Horizontal resistors
Add R41 to R4 , R48 to R 1.
Control the resistor values with a digital multimeter. Bend the leads at 0.4” with a lead forming tool.
2. Diodes
Add D10, D11. These diodes are installed vertically, cathode (black ring) on top.
Warning: Make sure to respect the direction of the diodes which is marked by a ring on the component
and a “k” on the PCB marking.
3. Vertical resistors
Add R46 & R47.
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DI board Assembly guide
4. Film capacitor
Add C22.
. Transistors
Add Q1 and Q2.
The PCB has provision for two pinouts for Q2. With the current 2SK170, use the A position.
Warning: Q1 (2N7000) is a device that is sensitive to static electricity before being soldered. It is safer
to handle it without your shoes on.
6. Electrolytic capacitors
Add C23, C24, C2 .
Solder one lead first, adjust verticality then solder the second lead.
Warning : The +lead must go into the +hole. Do not reverse (they may explode !)
7. Connector
Solder the connector CN3. Solder one pin first, check verticality, then solder the other pins.
Warning : the connector pins must be exactly perpendicular to the PCB to allow proper insertion in the
preamp board.
8. Jack connector
Add CN1. The position of the socket is important for a good front-plate matching. It must sit flat
on the PCB. Press firmly the socket on the PCB and solder one of the pins. Check position then solder
the other pins.
Warning : the hole must face outside the PCB ;-)
9. Visual check
Brush the solder side with a hard tooth brush to remove any remaining solder bits. Make a full visual
check. The DI board is ready for testing !
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Document revision 2.1 – Last modification : 11/09/20
Final assembly
10. DI bBoard installation
Place one 1.2mm plastic spacer on the jack sockets and insert into the front panel while fitting the CN2
connector pins into the socket on the preamp PCB. Screw in the front nut through the beveled front
spacer with an M12 socket spanner.
11. Closing
With cutting pliers, cut the 4 lugs attaching the
transformer opening. Cleanup the cuts with a small
file.
Attach the cover PCB with four M3x6 countersunk
screws.
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Document revision 2.1 – Last modification : 11/09/20
Final assembly
12. Congratulations !
You're done !
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