the Boss schematic

I don't want to simply place a copy of the full Boss schematic here in this blog, because I'm not exactly sure about its copyright status.  However, it seems to be "freely available" online, such as from this link:

https://www.audioservicemanuals.com/b/boss/boss-dc/329776-boss-dc-2-dimension-c-chorus-schematic

Thank you to Boss for permitting, or at least not obstructing, this!  I wish TC Electronic would follow suit, but so far in my searches, it appears they have not done so.

Identification of the significant, "non-obvious" chips in the Boss circuit:

BA634: flip flop

NE570: compandor

MN3102: clock generator for analogue delay line

MN3207: 1024-stage BBD delay line

One thing that I note about the schematic (this is the Boss DC-2, i.e., the original Dimension-C, not the newer WazaCraft version).  Although this unit provides "stereo" outputs, there are still only two delay lines as far as I can tell.  I haven't extensively analyzed the schematic beyond just the LFO portion, but I believe that indicates that the stereo effect is probably accomplished by sending one delay line out to each of the two stereo outputs.  In most situations, this would certainly give a good stereo spread, but in certain cases it might be problematic to only have "half" of the dimension signal in each stereo channel.  E.g., through headphones, or in a live situation with a big PA system, where some members of the audience might be much closer to one speaker than the other, the "motionless" dimension effect might be lost, decaying into a "regular" chorus sound where the waveform of the LFO is clearly audible.  I'm not sure, maybe Boss have used resistors to mix some portion of both delay lines into each output, to avoid an extreme version of this problem, but of course this would also weaken the intensity of the stereo spread.  Ideally, I think it would be good to have a "stereo width" pot, which could blend from mono to full stereo spread, to allow the user to adjust for different situations.  Failing that, in some situations as noted, one might be better off forgetting about the stereo effect and just running the pedal in mono.

But actually, if one really liked the dimension effect and wanted to use it extensively, in full stereo, the best bet might be to simply buy two mono TC Electronic 3rd Dimension pedals, one for each channel, and operate them on different settings.  This would give a better, more "genuine" stereo image than the trickery of just running one delay line out to each channel.  And two TC pedals are still significantly cheaper than one Boss pedal, either the used DC-2 pedals or the new WazaCraft ones, at least in today's market.


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