EFM 4600 Series - modular.fonik.de · 3544 High stability, high scale saw tri pulse sine VCO 4600 series ... An external input on the gate of the synchronisation transistor (Q1)

EFM electronics for music

EFM 4600 SeriesFebuary 2007


3500 series3544 High stability, high scale saw tri pulse sine VCO

4600 series4602 +/- 12V Regulated Power Supply4614 Low Parts count, high quality VCO4621 OB Sem Type 2P LP/HP/BP/Notch VCF4622 Moog Taurus Type 4P LP VCF4626 EMS Diode Ladder Type 4P LP VCF4627 Arp 2600 Type 4P LP VCF4628 Korg MS20 Type 2P LP/BP/HP VCF46212 Korg Delta Type 4P LP/BP VCF


Introduction:

EFM PC boards are easy to get parts for and assemble. I use the minimum amount of parts to getthe job done well. There are many ways to describe this kind of attitude. I like to call it economicaland efficient.

If you are new to building modular synthesizers I've tried to make it as easy on you as I could. All ofmy current pc boards are second or third generation.

VCO4aMad Mouse

BassAce

SBM

Mad MousePro

TomCat WildCat

SEQ1

RXCV RXCV Pro MidiGateVCF2

1900 Series

2400unreleased

35004600

The 2400 series remains unrelease.


3544 - VCOEFM Synthesizers

Freq

Fine

Saw

Pulse

Tri

Sine

PW

Saw

Pulse

SyncFM

PWM

Tri

Sine

Pitch Pitch

P Bend

3544 VCO voltage controlled oscillator

U1a,b and U2 from a linear voltage to exponential current sink. Thevoltage divider R28, R29 and U6b form a constant votage referance.As current flows from the referance to the sink C4 starts to charge.When the voltage at the output of buffer (U3a) reaches the thresholdlevel of the comparator (U4b) it turns on . This turns Q2 on and resetsC4 then the cycle begins again. This oscillation forms a sawtoothwaveform on the output of buffer (U3b)

The sawtooth waveform is applied to the base of Q3. Q3 is a phasesplitter and U3a combines the signals to form a triangle waveform. Thesawtooth waveform is also applied to the non-inverting input ofcomparator U4a. U4a is biased through R28 so that it turns on as soonas the voltage starts to rise at the output of U3a. The output of U4a is avariable pulse waveform A voltage applied to U4a's inverting inputchanges the duty cycle altering the pulse width. The Sine output isformed by clipping and shaping the triangle wave with D1,D2 and U6a.

An external input on the gate of the synchronisation transistor (Q1)resets C4 regardless of whether U4b is on. Oscillation occurs in syncwith the controlling oscillator.

An FM input causes the oscillator phase (or center frequency) tochange with the signal amplitude or Phase Modulates the exponentialconverter.

efm 3544 VCO


R1100K

R2100K

R3100K

R4100K

R5330K

R62M2

R7100K

R11470K

R922K

R1010K

R1322K

R141KTC

R171M

R11470K

R121M

R154K7

R162K2

R1810K

R2810K

R2910K

R3210KR31

10K

R301M

R272K2

R3310K

R34100K

R35100K

R4222K

R43b10K

R2310K

R2210K

R2160K *

R2410K

R2510K

R2610K

R441K

R3739K

R4322K

R4010K

R411K

C10.1uF

C20.1uF

C3100pF

C4.01uF

C5100pF

C7100pF

C6470pF

Q1 Q2

Q3

U2LM3046

1

2

3

4

5

86

7

9

11

10

1412

13

T150KInit

T250K

Scale

T310KHS

U1a

U1b

U6b

U4b

U3b

U4a

U3a

U6a

12

3

76

5

76

57

6

5

12

3

12

3

76

5

R391K

R3610K

R1910K

R201K

Sync

1V/Oct

Freq

Fine

FM

PWM

J1

J2

J3

J4

J5

J6

J7

J9

J10

J11

J12

J8

P150K

P250K

P350K

P450K

P550K

P650K

P750K

PW

Link

+C8

10uF

Parts List

R1,2,3,4,7,34,35R34,35 100K 7R5 330K 1R6 2.2M 1R8,11 470K 2R9,13 22K 2R10,18,19,22,23R24,25,26,28,29R31,32,33,36,40R43b 10K 16R12,17,30 1MR14 Not UsedR15 4.7K 1R16,27,43a 2.2K 3R20,39,41,44 1K 4R21 60K (33K + 27K) 1R37 39K 1R38,42 22K 2TC 1K Tempco 1

C1,2 0.1uF 2C3,5,7 100pF 3C4 .01uF 1C6 470pF 1C8 10uF 1D1,2 1N4148 2Q1,2 J112 2Q3 2N3904 1U1,3,6 LF353 (TLO72) 3U2 LM3046 1U4 LM393 1U5 Not UsedT1,2 50K Trimmer 2T3 10K Trimmer 1P1,2,3,4,5,6,7 50K Pot 7J1-12 1/8th Jack 12

R43a2K2

efm 3544 VCO


C8 10uF

Sine TrimNot Used

+

A

B

Correct tempco resistorinstallation inside the socketunder U2.

R43A and R43b

efm 3544 VCO


Freq

Fine

Saw

Pulse

Tri

Sine

PW

Saw

Pulse

Sync FM

PWM

Tri

Sine

PitchPitch

Mod

Ground

Saw out

R5 Freq

-V

+V

R6 Fine

R42 SQ out

R44 Tri out

R36 PW

R35 PW

R41 Sine out

Sync InR11 FM

R1 Pitch

R2 Pitch

R3 P Bend

R34 PWM

PWM

R4 Mod

efm 3544 VCO


Power Supply

The 4602 power supply is adjustable from +/- 2.5VDCto +/- 18VDC at about 2 amps, with proper heat sinking.

EFM kits are designed for +/- 12VCD operation.

The 4602 uses the LM317 and LM377 voltageregulators. The kit contains separate snap-on T0-220heat sinks but for the best heat transfer use a largerpiece of aluminum and heat transfer compound.

Note: The regulator cases are not at the samepotential and mica insulators must be used if they aremounted on the same heatsink.

This supply will easily power small synthesizers. Forlarge modulars we recommend the use of the excellentPowerOne(TM) regulated power supplies.

This is a updated version of the 2402 power supply. It iselectronically identical only the I/O pins were replacedwith locking headers.

Ther 2402 version is shown here

Power

4602 - PWREFM Synthesizers

efm 4602 Power Supply


Transformer12VACT @ 2AAC

S1 D1

D2

D3

D4

+

+

C11000 uF

C21000 uF

T15 K

T25 K

C510uF

C310uF

C610uF

C410uF

+

+

+

+

R2120

R3120

D5

D6

D8

D7

+V

-V

Small PartsR1 Not Used 1R2,3 120 ohm1/4w 1% resistor 2T1,2 5K 10T trimmer 2C1,2 1000uF 35V electrolytic 2C3,4,5,6 10uF 35V electrolytic 4D1-8 1N4001 Diode 8U1 LM317 1U2 LM337 1

Rare PartsS1 - SPST Switch 1L Bracket w/hardware 2Panel 1Overlay 1

Transformer (Not Supplied)XFM - 24VAC 2A transformer 1

Adj.

Out

In

LM317

Adj. Out

In

LM337

LM317 LM337

Adj. Out

In

Adj. In

Out

efm 4602 Power Supply

EFM electronics for music efm 4602 Power Supply


4614 - VCOEFM Synthesizers

Pitch Fine

Init

Level

Square

Tri

Pitch

Tri

In

Square

CV1 CV3

VCO

VCA

Sine

CV2

Sine

Sync

Out

CV

efm 4614 VCO

4616 VCO and VCA:

Features

Low costLow parts count+/- 12 to15VDC operation.Standard Frac-Rack PanelLevel Control on all outputs

This OTA core VCO is based on the NationalSimiconductor application notes. It has one one-voltper octive input, sync and three control voltageinputs for modulation.

The outputs are very nice. Featuring native triangleand square outputs. The sine output is derived fromthe tri using a system 100 style tri to sine converter.

There is a classic OTA VCA also on this board justbecause it's always nice to have lots of VCAsaround.

For the most stable operation replace R1 with a 1Ktempco resistor, replace Q1 and 2 with a pnp pairand wrap all three pieces with heat shrink tubing forgood thermal contact.

I don't have time to go further into it inthis document but this board can beconfigured as a VCO with a sineoutput and VCA as shown or with afew fairly easy mods you can...

Convert the sine out to a saw.Convert VCO to VCA for dual VCAVCLFO with mod VCA


R122K

T150K

R5Jump

R6100K

R71K

R8220K

R910K

R101M

R1110K

R1210K

R131K

C3.01 R14

10K

R153K3

R1610K

R1722K

R18100K

R19150K

R2022K

R212K2

R2222K

R231K

R24100K

R251K

R261K

R2710K

R2833K R29

10K

R301K

R31100K

R32100K

C4.01

1

54

3

7 81

2

3

76

5

1213

14

10 9

16

A

B

E

F

G

H

J

K

L

M

I

Q1 Q2 D1 D2

Q3

C10.1uF

C20.1uF

Parts List

R1 22K 1R2,3,4,6,18,24,31,32 100K 9R5 JumperR7 1K Tempco 1R8 220K 1R9,11,12,14,16,27,29 10K 7R10 1M 1R13,23,25,26,30 1K 6R15 3.3K 1R17,20,22 22K 3R19 150K 1R21 2.2K 1R28 33K 1

Extra Resistors for 330K 1VCO/VCA 2.2M 1

C1,2 0.1uF 2C3 0.01uF 1C4 0.05uF 1D1,2 1N4148 2Q1,2,3 2N3906 3U1 LM13600 1U2 LF351(TLO72) 1

T1 50K Trimmer 1P1-7 50K 7J1-12 - 1/8" Mini Jacks 12

efm 4614 VCO

2M2

330K

50KFine

50KFreq

CVInputs

1V/OctInput

Sync

In

CV

50KInit

50KLevel Out

CV Link

C

D

R2100K

R3100K

R4100K


PitchFine

Init

Level

Square

Tri

Pitch

Tri

In

SquareCV

CV2

Sine

CV1

Sine

Sync

Out

CV

330K

2M2

CV3

Ground+V

E

J

H

G

MI

B

C

DA

F

KL

efm 4614 VCO


4621 - VCFEFM Synthesizers

Cutoff

Res

HP

BP

LP

Mode Notch

Signal In

CV

HP LP

BP Notch

efm 4621 VCF

4621 - Voltage Controlled Filter:

Mulit-mode filter featuring simultainious hi-pass, band-pass, low-pass and notch outputs. The 4621 is basedon the Oberheim SEM filter.

This incarnation of the VCF1 is a little different thanpast versions. Usually this type of filter runs right upto the edge of self oscillation and hangs right there.This version goes over the edge and self oscillates.

Features



R1100K

R2100K

R3100K

R4100K

R5100K R7

100K

R6100K

R81K

R91K

R2510K

R1010K

R11100K

R131K

R121K

R2610K

R1410K

R161K

R171K

R18100K

R19100K

R20100K

R21100K

R22100K

R231K

R2410K

C3220pF

C4220pF

50KRes

R1,2,3,4,5,6,7,11,18,19,20,21,24 100K 13R6 150K 1R8,9,12,13,15,16,17,19,23 1K 9R10,14,25,24,26,25,26 10K 7R22 47K 1C1,2 0.01uF 2C3,4 220pF 2U1 TLO71 1U2 LM13600 1Q1,2 2N3906 2P1-P7 50K 7J1-J12 1/8 Mini Jacks 12

Parts List

R151K

C10.1uF

C20.1uF

K

L

M

N

H

A

B

C

D

E

F

L

62

3

4

35 7 8

13

1412 10 9

161

U1TLO71

U2LM13600

Q1 Q2

Q1,22N3906

efm 4621 VCF

Inputs HP

BP

LP

Notch

50K

50K

50K

Mode50K

50K

50K

EFM electronics for music efm 4621 VCF

Cutoff

Res

HP

BP

LP

ModeNotch

Signal In

CV

HPLP

BPNotch

+V

Ground

D

E

N

H

F

L

K

L

M

A

B

C



Cutoff

Res

Level

Inputs CV1 OutputCV2

efm 4622 VCF

The 4622 is a Moog Tauras type 4 pole low passvoltage controlled filter. This is the no compromiseversion. The stuff huge bass is make with.

Features



R1100K

R2100K

R3100K R4

1KR51K

R61K

R72.2K

R8100R

R9100R

R102K2

R111K

R121K

R131K

R14470K

R1510K

R1633KR17

10K

R18100K

R19100K

R20100K

R21150K

R221K

R234.7K

R2410K

C310uF

+

C410uF

+

C6

C7

C8

C9

C6-90.1uF

C510uF

+

C1010uF

+

C1110uF+

R251K

efm 4622 VCF

Parts List

R1,2,3,18,19,20 100K 6R4,5,6,11,12,13,22,25 1K 8R7,10 2.2K 2R8,9 100 1R14 470K 1R15,23 10K 2R16 33K 1R17 47K 1R21 150K 1R24 470 1C1,2,6,7,8,9 0.1uF 6C3,4,5,10,11 10uF 5Q1,2,3,4,5,6,9 2N3904 7Q8 2N3906 1U1 LM30461U2 LM13600 1P1,3 50K 2P2 10K 1J1-12 1/8 Jack 12

P210KRes

P350K

Level

P150K

Cutoff

Inputs

CV

Output

Q72N3904

Q82N3906

11 8

69

10 7

1 5

2

3

4

16

14

15

4

35 7 8

1

U1LM3046

U21/2 LM13600

Q1-62M3904

Q1 Q2

Q3 Q4

Q5 Q6


Cutoff

Res

Level

InputsCV1Output CV2

D

Ground

+V

E

I

J

BCFGH


Cutoff

Res

Output

Out


In 1 CV1 CV2

ResCV

In 2 In 3

4626 VCF voltage controlled filter

The 2426 vcf is a classic EMS type diode ladder with OTAdifferencing amp.

Voltage applied to summing transistor Q3 is applied to theexponential transistor Q4. Q4 and R19 form a emitterfollower providing exponential transistor base to emittervoltage compensation for changes due to temperaturevariations. The voltage applied to the base of theexponential-transistor causes a exponential collectorcurrent sink that's applied to the diode ladder through R20.The transistor pair Q1-2 splits the current supplied to R20into equal parts when there is no audio on the base of Q1.When audio is present, both left and right sides of theladder are modulated inversely. As current flow increasesthe impedance of the ladder is decreased providing ahigher cutoff frequency by way of the effective impedanceand C4-C7.

This inverse modulation on the ladder causes a push-pullvoltage to develop at the top of the ladder. These voltagesare applied to differencing and level shifting amplifier U1aand then to resonance amplifier U1b. The resonance signalmust be dynamically coupled through C19 because thebias levels between the ladder and vca are different.

efm 4626 VCF


R1100K

R2100K

R3100K

C310uF

+

R41K

R51K

R61K

R710K

C40.1uF

C50.1uF

C60.1uF

C70.1uF

C8220uF

+

R8470K

R910K

C1010uF+

R10100K

R11220

R1247K

R1310K

C910uF

+

R14100K

R15100K

R16100K

R17100K

R181K

R1910K

R201K

R21220K

R22220K

R231M

D1-D121N4148

R2410K

U1a

U1b

4

35 7 8

13

14

12109

16

1

Q1 Q2

Q3

Q4 Q5

J1

J2

J3

J4

J6

J5

P350K

CUTOFF

T150KINIT

P450KRES

A

B

C

D

E

F

G

H

I

U1LM13600

C10.1uF

C20.1uF

Small PartsC1,2 .1uF Ceramic 2C3,9,10 10uF Ceramic 3C4-7 0.1uF Mono 4C8 220uF Ele 1R1,2,3,14,15,16,17 100K 7R4,5,6,19 1K 4R7,13,20 10K 3R8 2.2K 1R9,11 470K 2R10,12 47K 2R18 150K 1U1 CA3080 1Q1,2,4,6 2N3904 4Q3 2N3819 1Q5 2N3906 1

Full PartsP1-3 50K 3J1-12 1/8 Mini Jacks 10Knob 3L Bracket w/hardware 2Header 1Panel 1Overlay 1

efm 4626 VCF


Cutoff

Res

Output

Out In 1CV1CV2

ResCV

In 2 In 3

Ground

+V

F

G

I

ABCDE

H



Cutoff

Res

Level

OutputIn 1 In 2 In 3 CV 1 CV 2

efm 4627 VCF

The 4627 is a Arp 2600 type 4 pole low pass voltagecontrolled filter.

Features

Low costLow parts count+/- 12 to15VDC operation.Standard Frac-Rack PanelLevel Control on output


R1100K

100K

100K

R2

R3

220R4

220

220 220 220 220 220 220 220 220

R647K

150KR5

R7Q1 Q2

C70.1uF

10KR10

10KR11

470pF 470pF 470pF 470pF

10KR13

10KR15

10KR19

10KR21

10KR24

10KR27

C3 C4 C5 C6

R8 R12 R14 R17 R18 R22 R23 R26

R10 R16 R20 R251K 1K 1K 1K

100KR28

10KR29

10KR30

10KR39

10KR38

47KR37

1KR36

47KR35

100KR32

100KR33

100KR34

C10.1uF

C20.1uF

B

C

D

A

E

F

G

H5

714

1 6

4

2 3

9

13 8

10

12 11

12

3

76

5

U2a

U2b

U1a U1b U1c U1d

P250K

Resonance

T150KInit

P150K

Cutoff

CV1

CV2

Inputs

Output

Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10

Q11 Q12

U1LM3900

U2LF353

Q1-Q122N3906

Parts List

R1,2,3,28,32,33,34, 100K 7R4,7,8,12,14,17,18,22,23,26 220R 10R5 150K 1R6,35,37 47K 3R9,11,13,15,19,21,24,27,29,30,39 10K 11R10,16,20,25,36 1K 5C1,2,7 0.1uF 3C3,4,5,6 470pF 4Q1-10 2N3906 10U1 LM3900 1U2 LF353 1

efm 4627 VCF


Cutoff

Res

Level

Output In 1In 2In 3CV 1CV 2

G

Ground

+V

H

A

FE

ABC

The silkscreen for Q11and Q12 is reversed

Correct Installation



Cutoff

Res

LP

LP In 1

HPIn

BPIn

LP In 2 LP In 3 CV 1 CV 2 LP Out

BP

BP Out

4648 VCF voltage controlled filter

The 4628 is based in the korg MS20 filters.

U1a and U1b are identical integrators connected inseries. The gain of these amplifiers determine thecenter frequency of the filter. The gain is set by biascurrent supplied by constant current source Q1 and Q2.The ratio of currents through these two transistors is arough exponential function of the voltage differencebetween the bases. Current supplied from Q2 isreasonably constant and repeatable. Band and low-pass outputs are all available at the same time.

efm 4628 VCF


R2110K

R110K

R210K

R310K

R4220

R5220

R610K

R710K

R810K

R910K

R10220

R11220

R1210K

R1310K

R1447

R1510K

R161K

R171K

R182K2

R2010K

R194K7

R22100K

R23100K

R24100K

R25150K

R261K

R2710K

A

B

C

D

E

F

G

H

J

C10.1uF

C20.1uF

D1 D2 D3

D4 D5 D6Q1 Q2

U2

U1 U1

K

I

Small KitC1,C2 0.1uF Ceramic 2C3,C4 220pF Ceramic 2R1,2,3,4,5,6,7,8,9,12,13,15,20,21,27 10K 15R4,5,11,12 220 ohm 4R14 47 ohm 1R16,17,26 1K 3R18 2K2 1R19 4K7 1R22,23,24 100K 3R25 150K 1P1,P2 50K Pot 2D1-6 1N4148 6Q1,Q2 2N3906 2U1 LM13600 1U2 LF353 (TLO72) 1

Parts KitP1-5 50K 4J1-12 1/8 Mini Jacks 11Knob 4L Bracket w/hardware 2Header 1Panel 1Overlay 1

4

35 7 8

13

1412 10 9

C3220pF

C4220pF

62

3

U1LM13600

U2TLO71

efm 4628 VCF

50KBP

50KLP

50KRES

50KCUTOFF

CV

LPInputs

HPInput

BPInput

BPOut

LPOut


R10

U1 PIN 14

GROUNDCutoff

Res

LP

LP In 1

HPIn

BPIn

LP In 2LP In 3CV 1CV 2LP Out

BP

BP Out

+V

GROUND

C

H

J

G

BA

DEF

KI



Cutoff

Res

Level

In 1 In 2 In 3 CV 1 CV 2 Output

LP

BP

efm 46212 VCF

The 46212 is a Korg Delta type 4 pole low pass voltagecontrolled filter. Selectable HP, BP.

Features

Low costLow parts count+/- 12 to15VDC operation.Standard Frac-Rack PanelLevel Control on output


C10.1uF

C20.1uF

R1100K

R2100K

R3100K

+

C310uF

R4100K

R6100K

R5100K

R71K

R81K

R9100K

R1010K

R11100K

R121K

R131K

R14100K

R1510K

R16100K

R171K

R181K

R19100K

R2010K

R21100K

R221K

R231K

R24100K

R2510K

R2675K

R27100K

R28100K

C4.001

C5.001

C6.001

C7.001

C810uF

+

U1aU1b

D1 D2 D3

D4 D5 D6

4

35 7 8

13

1412 10 9

1 16 1 16

4

35 7 8

13

1412 10 9

12

3

76

5LP

BP

R29100K

R30100K

R32100K

R31150K

R331K

R3410K

Q1 Q2

Q1-Q22N3906

U1LF353

U2a U2b U3a U3b

U2-U3LM13600

C

B

A

DE

F

G

H

I

J

K

L

Parts List

C1,2, 0.1 2C3 10/16 1C4,5,6,7 .001 4C8 47/35 1R1,2,4,5,6,9,11,14,16,19,21,24,27,28,29,30,32 22K 18R10,15,20,25,34 10K 5R31 150K 1R7,8,12,13,17,18,22,23,33 1K 9R26 33K 1P1,2 50K 3D1-6 1N914 6Q1-2 2N3906 2U1 LF353 (TLO72) 1U2,3 LM13600 11/8 PHONE

efm 46212 VCF


Cutoff

Res

Level

In 1In 2In 3CV 1CV 2Output

LP

BP

Ground

+V

A

K

I

L

H

J

D

B

C

E

F

G

Documents

EFM 4600 Series - modular.fonik.de · 3544 High stability, high scale saw tri pulse sine VCO 4600 series ... An external input on the gate of the synchronisation transistor (Q1)