Rocktave Divider Sound

[marlin]

Hi!

For those of you who have built or listened to the Rocktave Divider, how "synthy" is it? I don't like "synthy", that's why I'm asking. Can it be "undialed" perhaps? Other comments about the sound is welcome.. fuzz, growl?
Thanks

[Gripp]

IMHO it is pretty synthy. I like both synthy and more tamed down tones so I did a simple cap switching mod on the tone control to select different caps to roll off frequencies below what the original cap could do. At the other extreme, one position even disables the tone control for a max synthy tone. All along the lines of what is in the mod section of the original build notes. This approach works for me to get a wider range of tones, including some more bass like ones.

Thing is, the tone control is just a simple RC so the rolloff is just 6 dB/octave and you get heavy signal losses when trying to get just the fundamental say two octaves down. Then you have to turn up the levels of that octave and in some cases the expander part of the NE then starts to distort and behave weirdly in a totally unusable way. The levels for the various octaves are pre expander and the tone control circuit is post so there you go.

But it's a simple mod that you can play with and it works for me. Just remember that no matter what, the rocktave puts out square waves on all of it's outputs and the sound of square waves seem to be almost the definition of synthy sounds. Those squares have nothing in common with your original signal except the frequency relationship. You then sculpt those waves a little using the tone control or maybe add an external filter.

Hope that helps.
Best!

Pelle G

[Jaicen_solo]

I've still not got my rocktave project working, but I have spent a LONG time looking at the schems, and I agree with Gripp regarding the tone control. A better implementation would have been to have another dual op-amp and stick in an active buffer and eq pre-expander. That would go a long way to solving the deficiencies, but I guess it ups the complexity a little more (not that it's a difficult build really).

[Mark Hammer]

One of the ways in which the Rocktave sounds a little "synthy" is actually quite common to all octave dividers, and that is the fact that the flip-flop division is an all-or-none function, so pretty much all the dynamics are in the clean signal, with the f/2 and f/4 outputs providing a steady level just like an oscillator.

In theory, it should be possible to take those flip-flop outputs and do something fancy-schmancy with them, like alter the rise/fall times with something like the Beausoleil/Escobedo Square-wave shaper.  It should also be possible to mix them together (sans clean and fuzz) and harness them to some sort of input-envelope-controlled VCA to achieve a more dynamic feel.  But at that point, you've gone beyond what the board layout supports and are into kluging.

Like Gripp, I also found the range of treble-cut from the stock tone control insufficient for my needs and used a bigger cap value.

Just note that when using a f/4 signal, you're looking waaaaaaaaaayyyyy down to the bottom of the audio spectrum (same is true of Bluebox, POG, et al).  What you hear out of the speakers can often be a function of what your speakers/cab/amp can support, and not what the pedal itself is doing.  Of course, that's a musical effect too, just as speaker breakup is a musical effect.  Just keep in mind that if you don't like what you hear, the blame may sometimes be placed on asking your rig to do something it is not capable of, and not necessarily on a pedal or its build quality and component selection.

[SonicVI]

It should also be possible to mix them together (sans clean and fuzz) and harness them to some sort of input-envelope-controlled VCA to achieve a more dynamic feel.  But at that point, you've gone beyond what the board layout supports and are into kluging.

Isn't that more or less what Anderton attempted to do by using using the expander in the 571 after the division?

[Gripp]

Just note that when using a f/4 signal, you're looking waaaaaaaaaayyyyy down to the bottom of the audio spectrum (same is true of Bluebox, POG, et al).  What you hear out of the speakers can often be a function of what your speakers/cab/amp can support, and not what the pedal itself is doing.  Of course, that's a musical effect too, just as speaker breakup is a musical effect.  Just keep in mind that if you don't like what you hear, the blame may sometimes be placed on asking your rig to do something it is not capable of, and not necessarily on a pedal or its build quality and component selection.

This can't be stressed enough. It is fun to run an octaver direct into something that can reproduce those sub lows though.

I haven't heard/tried it myself but some say that the difference between the pure "make a square wave and divide it" octaves ala rocktave and blue box and indirect boxes, those that chop up the original signal at the divided rate like Boss OC-2 and the Pearl OC-7, is that the latter types sound somewhat cleaner and more dynamic. Read all about it here: http://www.diystompboxes.com/smfforum/index.php?topic=44451.0. Thanks to Mr Octave, Mark Hammer.
For the record, I think the rocktave tracks better or at least as good as the boss, but I've never had an opportunity to try them in an A/B situation.

It should also be possible to mix them together (sans clean and fuzz) and harness them to some sort of input-envelope-controlled VCA to achieve a more dynamic feel.  But at that point, you've gone beyond what the board layout supports and are into kluging.

Isn't that more or less what Anderton attempted to do by using using the expander in the 571 after the division?

When first building it, I thought so too, but mine doesn't seem to follow the dynamics at all up until the decay phase where the rocktave cuts off a little early to avoid sputter at the end of the note. Maybe something is missing from my build. But, a lot of what Anderton says about the dynamics in the build notes could also be interpreted as just pertaining to the decay stage.

[Mark Hammer]

It should also be possible to mix them together (sans clean and fuzz) and harness them to some sort of input-envelope-controlled VCA to achieve a more dynamic feel.  But at that point, you've gone beyond what the board layout supports and are into kluging.

Isn't that more or less what Anderton attempted to do by using using the expander in the 571 after the division?

Yes and no.  IF there was no further alteration of the dynamics between the compression and expansion, you'd be right.  Divide the dynamic range of something by half, then multiply it by 2 and you get what you started out with, right?  The conversion to steady-amplitude square wave by the flip-flop, however, removes all post-compression dynamics, so when you expand again there is not really anything to properly "restore".  I'm not saying there is NO dynamic impact of the expansion, but it's not like the analog-delay scenario where the signal never has any further dynamic restrictions or alterations placed on it between when it leaves the compressor and returns to the expander.