RE-301 Chorus clone?

[Sage]

Has anyone ever cloned the exact chorus circuit from a Roland RE-301 Chorus Echo tape delay?  I know it's very similar to the CE-1, of which there are plenty of clones, but the RE-301 seems to have a higher fidelity, partly due to the MN3004 bbd chip (IC8 on the schematic), and possibly because of the differences in the preamp.  If it hasn't been done before, are there any engineers here willing to help me isolate the chorus effect (and perhaps the preamp and output eq) from this schematic and build it into a pedal?  I've got a couple of MN3004 chips that could use a purpose.

[Kevin Mitchell]

That looks grossly complex. However possible!
Better off doubling the clock frequency and using MN3007 BBDs - more common. That way all of the development effort isn't limited to a discontinued & rare chip.

The RE-301 is new to me. It looks so nice  :'(
Here's the service manual which makes it look even more intimidating.

[PRR]

What, no garden-hose delay line?

[ElectricDruid]

What, no garden-hose delay line?

Lol, that's about the only thing they left out...

[StephenGiles]

Has anyone ever cloned the exact chorus circuit from a Roland RE-301 Chorus Echo tape delay?  I know it's very similar to the CE-1, of which there are plenty of clones, but the RE-301 seems to have a higher fidelity, partly due to the MN3004 bbd chip (IC8 on the schematic), and possibly because of the differences in the preamp.  If it hasn't been done before, are there any engineers here willing to help me isolate the chorus effect (and perhaps the preamp and output eq) from this schematic and build it into a pedal?  I've got a couple of MN3004 chips that could use a purpose.


It's not that complicated once you break it down to separate building blocks, I would certainly build it on veroboard (as always) if I had the need/could be bothered!!

[Rodgre]

I have a 301, 501 and a CE-1. Their chorus effects are all pretty close to each other, to my ears, for practical uses. Indistinguishable in a mix, honestly, but they're all fantastic.

I'll never try to talk a diy-er out of attempting something, but for me, as a bona fide chorus freak from way back, other than the few that I don't like (mostly because their internal preset delay time or mix level are just not to my tastes), I can do whatever I need to with any number of analog choruses that flooded the market in the 80s and 90s. The simpler, the better, usually. I love the 301/501/CE-1 only having one knob handling rate and depth. It just sounds great.

That said, keep us posted if you attempt a DIY RE-301 chorus!

Roger