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1590B · 3 knobs

Tagboard Effects

Mad Professor Forest Green CompressorVerified

Based on the Mad Professor Forest Green Compressor· 2 other boards clone it

Category
Compressor
Controls
Comp · Tone · Level
Build
Vero· 21×22· 26 cuts, 6 links
Layout
Verified · Tagboard Effects marks it as built and working
Tags
BJF/MP, Compressor

From the post

Another request. This was a bit of a pain to make 1590B friendly, especially with my aversion to standing resistors, but I just about managed it. Had to do a couple of things I don't like to do, like the grey external link and the angled component avoiding link (make sure that one is insulated), and the legs on that 47n are spectacularly long, but needs must.

Anyway, the info for the original:

BJF design guitar and bass Compressor/Sustainer pedal

FOREST GREEN COMPRESSOR (FGC) is designed to meet the highest standards of guitar and bass compression. There is extremely low noise throughout the range and a high overload margin, which allows also a wide dynamic input range at minimum distortion and noise. FGC is equipped with a special tone control to fine-tune the compressed sound for most transparent tone and effect. The pedal has a switchable compressor and sustainer mode. In Sustain mode you can get a very dynamic, touch sensitive tone with a long sustain. Here the attack is not lost, making the pedal suit-able even for blues players and works great with slide playing. Like all Mad Professor pedals FGC is hand made in Finland using only premium compo-nents, to give years of trouble free operation with superb musical tone.

Controls

LEVEL: in Compressor mode adjusts the overal volume and the FGC can be used even as a booster. In Sustain mode the Level no longer adjusts total output but the level of the sustained part.

COMPR.: Sets the amount of compression and sustain. Lower settings give mostly peak limiting, higher settings more compression and less touch sensitive response. At maximum the output will be heavily compressed, while still retaining clarity at almost infinite sustain. A good starting point for this control is a bit below centre (ten o’clock) with most guitars.

TONE : Tone control on FGC is designed to fine-tune the compressed sound for most transparent tone and effect: Adjust CCW for full range compression and set at noon for tighter sound with a little less bottom end and turn fully CW to slightly reduce upper treble.

COMPRESSOR/SUSTAIN SWITCH: Attack and decay times are carefully fine-tuned and internally set for swift attack and slow decay. Sustain/Compression switch set for Sustain the attack is preserved allowing dynamic touch and ease of playing as the FGC amplifies the decay and weaker parts. For standard compression set mode switch to Compressor.

Now verified:

Schematic

This is a board layout, a drawing of where each part goes, and the post may link the schematic it was drawn from. Open the layout at Tagboard Effects. No KiCad fragment has been drawn for this circuit yet.

Parts list 40 rows

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Check before you build · 4 values the reader of this layout was not sure of
  • 147K (three of them, upper half of the board): printed clearly, unusual value
  • 16K9 (upper centre, right of Q5): printed clearly, unusual value
  • 285R (right edge, mid board next to a 22u can): printed clearly, unusual value
  • 130K (upper left, beside the 147K): printed clearly, unusual value
RefValueNormalizedTypeNotes
Resistors 17
×227K27kread from the layout by eye
×12M2Mread from the layout by eye
×1470R470read from the layout by eye
×1130K130kread from the layout by eye
×3147K147kread from the layout by eye
×310K10kread from the layout by eye
×156K56kread from the layout by eye
×116K916.9kread from the layout by eye
×31M1Mread from the layout by eye
×247K47kread from the layout by eye
×122K22kread from the layout by eye
×2110R110read from the layout by eye
×2200K200kread from the layout by eye
×1285R285read from the layout by eye
×35K65.6kread from the layout by eye
×12K42.4kread from the layout by eye
×11K1kread from the layout by eye
Capacitors 7
×147p47pread from the layout by eye
×247n47nread from the layout by eye
×3100n100nread from the layout by eye
×2220n220nread from the layout by eye
×41u1uelectrolytic; three round cans and one drawn as an axial box; read from the layout by eye
×522u22uelectrolytic; three round cans and two drawn as axial boxes; read from the layout by eye
×247u47uelectrolytic; read from the layout by eye
Diodes 3
D11N40011N4001read from the layout by eye
D21N9141N914read from the layout by eye
D31N9141N914read from the layout by eye
Transistors 5
Q12SK1702SK170JFET; read from the layout by eye
Q2BC550CBC550Cread from the layout by eye
Q3BC550CBC550Cread from the layout by eye
Q4BC550CBC550Cread from the layout by eye
Q5BC560CBC560Cread from the layout by eye
ICs 2
ICAD797AD797legend: AD797 or NE5534; read from the layout by eye
Regulator78L0578L05read from the layout by eye
Opto 1
×1LDRLDRtype not given; read from the layout by eye
Potentiometers 3
CompA500KA500kPotentiometerread from the layout by eye
ToneA20KA20kPotentiometerread from the layout by eye
LevelB50KB50kPotentiometerread from the layout by eye
Switches 1
Compressor / SustainSPSTSPSTSw1; read from the layout by eye
LEDs 1
D45mm red LED5MM RED LEDon the board, next to the LDR; read from the layout by eye

Other boards based on the Mad Professor Forest Green Compressor