Mozztronics | BC-1 Badicota

You remember when i said i would never do a clone…. well, read on….

My captive studio engineer has an old “Rat” pedal from 1984 (or thereabouts), it has the LM308 chip in it, and it is the version before the led was added. He has tried various clones of this pedal over the years, but none of them sound quite like his old pedal. I know i am going to get into murky territory here, but here goes.
The magic in these pedals was the LM308 chip, which was noisy, slow and not good for audio (perfect for a dirt pedal). The LM308 chip was eventually made obsolete and the pedal manufacturer replaced it with the OP07 chip, which “on paper” should be a very good replacement, and (imo) while it still sounds fine in this circuit, it didn’t quite have exactly the same sound. This pedal has a lot of gain and slams the output of the LM308 chip hard against the 9V and 0V power supply rails and then hard clips it, and for me the mojo was how the LM308 chip responded to being used in this way, and how it recovered once it left being slammed against the power supply rails. The OP07 responds a little differently, and we can hear this in the sound of the pedal, and while it is still perfectly acceptable it just not quite the same as the LM308.

So, onto the story…. Now it was a challenge, could i make a clone that would sound the same as the old rat pedal. I didn’t want to use the OP07, so what were my options ?
If you have been following along at home you may recall a few years ago i did a big refurbishment on a Auditronics mixing desk from the 1970’s, i replaced a lot of LM301 chips with modern low noise equivalents, so maybe i could use these instead of the LM308. The LM301 is a lot faster and lower noise than the LM308, so there is my challenge. I changed a few parts values to slow down the LM301 chip.
The LM301 chip is also no longer made so all i have is what i pulled out of the Auditronics desk. The “other chip” is also becoming hard to find. The LM308 chip is obsolete, and the ones offered online (for stupid $) are mostly fakes.

So i made 3 versions to be compared to the original Rat. I used the LM301, another chip (which i wont detail here) and the OP07. My studio engineer and me set all three up with his original pedal, and then set up a blind test. We set gain at around 11 o’clock on the original and adjusted tone & volume for the best sound. All three of my pedals pedals were then adjusted to get as close to the sound of the original pedal as possible (i did the knob tweaking at the instruction of my studio engineer who had his back turned & couldn’t see which pedal i was tweaking).

So after exhaustive testing against the original we ended up as follows.
1. The LM301 version sounded virtually identical to the original, my studio engineer couldn’t tell whether he was hearing the original pedal or my clone
2. The “other chip” sounded almost like the original, but with a slightly more “modern” sound
3. The OP07 sounded close to the original, but didn’t quite have the bark & bite of the original

The old Rat pedals with the LM308 chip in them go for a lot of money secondhand these days, and now, after the testing we did, i see why people want the old ones, and not the newer production pedals. My captive studio engineer liked my version so much, he is selling his “old LM308 pedal” as he can get the same sound with the BC-1.

So, i am offering a limited run of these pedals as the BC-1 Bandicota, until the LM301 chips i have run out.
After that, while i can still get the “other chip” i will make the BC-2 version until the other chip is also unavailable.
Oh, and the Bandicota is a genus of rat, and it sounds a bit like “Bandicoot”, a species of mammal in Australia.

There it is, my journey to clone the much loved Rat pedal

Mozztronics uses the industry standard Boss style 2.1mm center negative 9V DC socket for the power supply connection.