Akashic Guitar effects circuit lookup
VOLUMEBASSTREBLE

Enclosure not stated · 3 knobs

Tagboard Effects

Montarbo SinfhotonVerified

Based on the Montarbo Sinfhoton· 5 other boards clone it

Category
Fuzz
Controls
Volume · Bass · Treble
Build
Vero· 12×13· 5 cuts, 3 links
Layout
Verified · Tagboard Effects marks it as built and working
Tags
Fuzz, Montarbo

From the post

Here's a pedal that caught my eye while looking for a new fuzz. It was made by an Italian company in 68.

It's very Big Muff like in tone, but seems to have a bit more clarity in the notes, and no Fuzz control, just Bass, Treble, and Volume. In my search for the schematic I found that over time there's been 3 different versions, so I made a layout for each, and then found that a few years ago by Miro actually made a layout for the later version. My layouts are a bit more compact, has less cuts & jumpers, and I put the CLR for the LED on the board, so I thought I would still post all of them, since while they have the same feel, each sounds a bit different.

Also, through my searching I found some mods people have done, and made a massively modded layout as well that I'll post later with a description of it all.

The video compares the stock vintage unit to a clone made by Brad at Creepy Fingers. Not sure what the extra pot does, but since it's full CW I can only assume it's a Fuzz Pot.

Earlier Version

Later Version

2 Knob Version

Notes:

• You may need to adjust the 2 10k resistors to the Collectors of Q1 & Q2 to bias the transistors right and have it sound good.

• Since BC149's are hard to come by, although I've seen them on eBay, you may want to try the usual suspects with higher gain. So transistors like 2N5088/2N5089, MPSA18, BC109, BC108, etc.

• For the 2 knob version you may want to change the 2uF caps to 10uF caps like the later version.

• For more fuzz remove the 100k or 1M resistor parallel to D1 & D2.

• I left out the usual 1M pulldown resistor as in all the videos I heard I didn't hear a pop from the vintage unit, so I felt it's not needed, you can always add it on the switch or just add an extra column.

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 17 rows

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Check before you build · 1 value the reader of this layout was not sure of
  • 2uF electrolytics (two, left edge and bottom): printed clearly, unusual value
RefValueNormalizedTypeNotes
Resistors 6
×410k10kread from the layout by eye
×21M1Mread from the layout by eye
×2100k100kread from the layout by eye
×147k47kread from the layout by eye
×14.7k4.7kread from the layout by eye
×1??LED resistor, value not given; read from the layout by eye
Capacitors 5
×1220nF220nread from the layout by eye
×1100nF100nread from the layout by eye
×110nF10nread from the layout by eye
×210uF10uelectrolytic; read from the layout by eye
×22uF2uelectrolytic; read from the layout by eye
Diodes 1
×41N41481N4148D1-D4: Si (try 1N4148, 1N914); read from the layout by eye
Transistors 2
Q1BC149BC149read from the layout by eye
Q2BC149BC149read from the layout by eye
Potentiometers 3
VolumeB10KB10kPotentiometerread from the layout by eye
BassB10KB10kPotentiometerread from the layout by eye
TrebleB10KB10kPotentiometerread from the layout by eye

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