Maxon CP101 Compressor

Stumbled across the schematic for this compressor and couldn't find a layout for it. So I drew it up. This follows the original red box version, not the black box reissue. It's an optical compressor and apparently fairly subtle. I couldn't find any info on the vactrol used in the original–sockets are your friend. Should be an easy fit in a 1590B.

Ibanez OD-850/Maxon D&S OD-801

There are a host of Big Muff clones and variation, but one of the most sought after clones is the Ibanez OD-850. Like all vintage Ibanez pedals, the OD-850 is just a rehoused and rebadged Maxon design–in this case, the D&S OD-801. While this shares a lot in common with a Ram's Head BMP, it differs greatly in the tone section. Here's Kit Rae's description:

Maxon opted to alter the tone stack for this clone, fixing the bass value across the tone pot sweep... The whole high pass and low pass tone section is incorporated into the recovery stage. What this did was to make the bass and treble sides have a more useful range of sounds. The treble side retains some bass across the sweep, so it is not as ear piercing and trebly as a standard BMP when dialed completely to the treble side, nor do the highs seem to be completely removed when dialed fully to the bass side. It kind of makes finding the 'sweet spot' a bit different sounding than the traditional BMP tone stack, but that is what makes this version unique.

I've laid this out for more common CBE pinout transistors, where as the C828s of the originals are BCE. This follows the first version released in 1974, and will fit in a 1590B with board mounted pots. Here's the schematic for reference.

Ibanez/Maxon SD9 Sonic Distortion

Originally produced in the early 80s, the SD9 was the distortion brother of the classic TS9 Tube Screamer. It ranges from mild overdrive to fuzz territory without losing articulation. The easiest way to describe the SD9 circuit is to say it's half of a Tube Screamer, with a Big Muff tone stack. Original units only used half of the JRC4558 opamp (the other half was used to buffer the non-distorted stage to output). However, General Guitar Gadgets published a schematic with the 2nd half of the opamp used as a volume recovery stage right after the tone stack. (And the BMP tone stack is notorious for volume loss) Who doesn't want louder distortion, right? So instead of the stock circuit, the layout below reflects the mods from GGG. I've added polarity protection and power filtering. Pots can be board mounted from the solder-side using right angle PCB pots.

Maxon OD808

Maxon released the OD808 in 1979 and it generates natural, mild overdrive tones and is similar to the TS808. Original units used MC1458P ICs, but I've listed JRC4558s as they're likely to be on hand for many of you. Also the original diodes were Panasonic MA150. I've listed 1N4148s as a replacement, but socket and experiment there. I've read of people using 1N60Ps or similar germanium diodes to give it an even more tube-like sound.

Maxon OD880 Soft Distortion Overdrive

The Maxon Company is probably most famous for manufacturing the legendary Ibanez Tube Screamer pedals (among many other Ibanez offerings). Because of this (and especially in non-Asian markets) Maxon pedals were often overshadowed by their Ibanez-branded brothers. But throughout the company's history, they have produced a great offering of effects.

The Maxon OD880 Soft Distortion Overdrive was first produced in the mid 70s, and originals are very rare, especially in the West. It used 3 ICs (741 types) to produce a great transparent overdrive effect. The pedal was reissued in the 90s exclusively in Japan with an updated circuit that used 2 opamps. The layout below is for the original 3 IC version. I've added power filtering and polarity protection. It should fit just fine in a 1590B.