I also had Muffsy boards made up , and herewith is a build thread for that set . Because these boards don't have exposed tracks and have solder masks on either side of the pcb , they are relatively easy builds .
These boards have evolved from the legendary "CNC phonostage" which is a community development started here : https://audiokarma.org/forums/index.php?threads/another-super-high-end-phono-stage-no-expense-spared.371889/
This concept was taken further by member Skrodahl who started the Muffsy builds . The nice thing about the Muffsy is that it has adjustable input impedance and adjustable gain and is a pretty decent phonostage . Other than built-in adjustaments it is also tweakable in terms of input capacitance , Adjustable gain can be further altered to suit one's preferences and it allows opamp rolling .
See links towards the top of this build thread for gain resistor calculators etc. : https://www.muffsy.com/build-the-muffsy-pp-3-rev-a.html
Muffsy Phono Preamp Specifications:
Total Harmonic Distortion: 0.00081%
Total Harmonic Distortion + Noise: 0.01935%
Signal to Noise Ratio: 82.3 dB (0 dBV output)
Intermodulation Distortion: 0.0195% (ITU-R)
Crosstalk: -102 dB
Dynamic Range: > 110 dB (THD+N < 1%)
RIAA Compliance: +/- 0.15 dB (20-20.000 Hz)
RIAA Equalization: Passive
Gain at 1 kHz: 32-43 dB, in four steps
Input Impedance: 17k-150k ohm, in fifteen steps
Input Capacitance: Optional
Phonoboard parts (parts listed are for PP3 rev A)
2x Resistors 0.25W, 100 ohm
2x Resistors 0.25W, 130 ohm
2x Resistors 0.25W, 180 ohm
6x Resistors 0.25W, 300 ohm
2x Resistors 0.25W, 2k2 ohm
4x Resistors 0.25W, 3k3 ohm
2x Resistors 0.25W, 16k ohm
2x Resistors 0.25W, 33k ohm
2x Resistors 0.25W, 82k ohm
4x Resistors 0.25W, 110k ohm
2x Resistors 0.25W, 150k ohm
2x 8-Pin DIL Sockets
2x 2-Way DIP Switches (pitch=2.5mm) sometimes referred to as p=2.54mm
2x 4-Way DIP Switches (pitch=2.5mm)
2x Operational Amplifiers
4x Ceramic Capacitors, 100 nF (pitch=5mm)
2x Polyester Film Capacitors, 47 nF (pitch=5mm or 10mm)
4x Polyester Film Capacitors, 68 nF (pitch=5mm or 10mm)
2x Polyester Film Capacitors, 1 uF (pitch=10mm or 15mm)
4x Electrolytic Capacitors, 22 uF (pitch=2.5mm)
2 x DG301 Screw Terminals, Two Positions (pitch=5mm)
2x DG301 Screw Terminals, Three Positions (pitch=5mm)
PSU board parts
6x Diodes, 1N4004
2x Resistors, 0.25W Metal Film, 300 ohm
2x Resistors, 0.25W Metal Film, 3300 ohm
2x Resistors, 1W, 4.7 ohm
4x Ceramic Capacitors, 100 nF (pitch=5mm)
2x Electrolytic Capacitors, 25V or higher, 10 uF (pitch=2.5mm)
4x Electrolytic Capacitors, 35V or higher, 2200 uF (pitch=7.5mm) 1000uF also quite adequate in this position
1x Voltage Regulator, LM317T
1x Voltage Regulator, LM337T
1x Screw Terminal, DG301, 2 Positions (pitch=5mm)
1x Screw Terminal, DG301, 3 Positions (pitch=5mm)
Other Parts
1x Wall Adapter transformer, 15-18V AC (16V AC doorbell transformer wallwart is quite common)
4x Female RCA chassis mount sockets
1x Speaker binding post (to tie turntable ground to)
1x 5mm chassis mount female power socket
1x 5mm male power plug
1x Enclosure
These boards have evolved from the legendary "CNC phonostage" which is a community development started here : https://audiokarma.org/forums/index.php?threads/another-super-high-end-phono-stage-no-expense-spared.371889/
This concept was taken further by member Skrodahl who started the Muffsy builds . The nice thing about the Muffsy is that it has adjustable input impedance and adjustable gain and is a pretty decent phonostage . Other than built-in adjustaments it is also tweakable in terms of input capacitance , Adjustable gain can be further altered to suit one's preferences and it allows opamp rolling .
See links towards the top of this build thread for gain resistor calculators etc. : https://www.muffsy.com/build-the-muffsy-pp-3-rev-a.html
Muffsy Phono Preamp Specifications:
Total Harmonic Distortion: 0.00081%
Total Harmonic Distortion + Noise: 0.01935%
Signal to Noise Ratio: 82.3 dB (0 dBV output)
Intermodulation Distortion: 0.0195% (ITU-R)
Crosstalk: -102 dB
Dynamic Range: > 110 dB (THD+N < 1%)
RIAA Compliance: +/- 0.15 dB (20-20.000 Hz)
RIAA Equalization: Passive
Gain at 1 kHz: 32-43 dB, in four steps
Input Impedance: 17k-150k ohm, in fifteen steps
Input Capacitance: Optional
Phonoboard parts (parts listed are for PP3 rev A)
2x Resistors 0.25W, 100 ohm
2x Resistors 0.25W, 130 ohm
2x Resistors 0.25W, 180 ohm
6x Resistors 0.25W, 300 ohm
2x Resistors 0.25W, 2k2 ohm
4x Resistors 0.25W, 3k3 ohm
2x Resistors 0.25W, 16k ohm
2x Resistors 0.25W, 33k ohm
2x Resistors 0.25W, 82k ohm
4x Resistors 0.25W, 110k ohm
2x Resistors 0.25W, 150k ohm
2x 8-Pin DIL Sockets
2x 2-Way DIP Switches (pitch=2.5mm) sometimes referred to as p=2.54mm
2x 4-Way DIP Switches (pitch=2.5mm)
2x Operational Amplifiers
4x Ceramic Capacitors, 100 nF (pitch=5mm)
2x Polyester Film Capacitors, 47 nF (pitch=5mm or 10mm)
4x Polyester Film Capacitors, 68 nF (pitch=5mm or 10mm)
2x Polyester Film Capacitors, 1 uF (pitch=10mm or 15mm)
4x Electrolytic Capacitors, 22 uF (pitch=2.5mm)
2 x DG301 Screw Terminals, Two Positions (pitch=5mm)
2x DG301 Screw Terminals, Three Positions (pitch=5mm)
PSU board parts
6x Diodes, 1N4004
2x Resistors, 0.25W Metal Film, 300 ohm
2x Resistors, 0.25W Metal Film, 3300 ohm
2x Resistors, 1W, 4.7 ohm
4x Ceramic Capacitors, 100 nF (pitch=5mm)
2x Electrolytic Capacitors, 25V or higher, 10 uF (pitch=2.5mm)
4x Electrolytic Capacitors, 35V or higher, 2200 uF (pitch=7.5mm) 1000uF also quite adequate in this position
1x Voltage Regulator, LM317T
1x Voltage Regulator, LM337T
1x Screw Terminal, DG301, 2 Positions (pitch=5mm)
1x Screw Terminal, DG301, 3 Positions (pitch=5mm)
Other Parts
1x Wall Adapter transformer, 15-18V AC (16V AC doorbell transformer wallwart is quite common)
4x Female RCA chassis mount sockets
1x Speaker binding post (to tie turntable ground to)
1x 5mm chassis mount female power socket
1x 5mm male power plug
1x Enclosure
