The RMA drawing board/etc.

[ibarakishi]

cool! exactly what i was hoping for, i will be looking out for the next time you do batches for these and your other new layouts. I am really excited about all the other things you are doing as well

[comesect2.0]

what was the gumball? remember seeing a yt video...
also recall seeing some bad ass custom swirled colour led...whats up with those?

[crochambeau]

what was the gumball? remember seeing a yt video...
also recall seeing some bad ass custom swirled colour led...whats up with those?

The gumball is the crackle section of the crustacean, being fed an input instead of a noise source. My discrete transistor chops are improving (been digesting old pre-IC analog computer texts) and I might have a go at recreating the stage without the 741. That largely ignored build fell off the radar and has been in the prototype anomaly pile, but it's not the first time this year it has come up in conversation, so I'll be sure it is not forgotten... my work in process on the drawing board is just quite a few projects deep, so it might take some time.

The cracked glass LED bezel is still on the drawing board. Currently, I have to hand fabricate a bunch of shit to get them to work right, and it's hard to convince myself that the labor upcharge to cover my time is worth the value. There are a few out in the world, and they're all more or less experimental additions I've stuck to builds. My plan is to draw up a .dxf set and take it to my local machine shop, from which point there will be A) consistency and B) a very fixed price on the part, from which point I can integrate them in builds in a way that is not me pushing time into the corner (some of them would have added up to a roughly $100 up-charge if I was doing a by the book cost to charge assessment on them, and I don't feel like they are THAT cool)

So - working on it! ..and thanks for the nudge regarding the gumball, this might actually be good timing for the reminder.

[crochambeau]

Copy/pasted from the facebook page, because I'm lazy like that (but without pics)

Highlights of this past month of R&D work:

The Tetanus Booster will either be getting optional variants or spawning another model. New development includes a top boost (for those who prefer chime) switch and a high gain mode that does not lose the buffered output.

These changes may spill over to the Monobius, which employs the root Tetanus Booster gain circuit in both diode bridge driving and recovery.

Observed differences in the timbre of the Fire section between the standard Crustacean and the Crustacean Brick, the latter being more similar to an electrical spark than an electro-mechanical pop (I liken the earlier models to LP crackle at low settings), provisions to provide both flavors of sound are forthcoming.

The RMA Crustacean is going to go through yet another mutation. The 1V4 I feel has wandered too far in too many directions, and as a result is at risk of losing touch with itself. Therefore, I intend on focusing on erosive processing and noise generation within the Crustacean species while directing chaos synthesizer approaches and methodology elsewhere. I do not have a solid time frame for the revision at this point in time.

The Dirty Doper Mk2 is still in deep refinement. I expect to see circuit level revisions that will demand drafting an entirely new PCB. There is continued interest in this design, so it remains on the short list of priorities, but it is not at the *top*. It IS near the top.

The Stone Splitter octave generator is currently a glitchy nightmare. Steady state performance is decent in this regard, though it is not within the confines of my original design criteria. Dynamic sources remain problematic, so as is the circuit is really tailored to synthesis and drum machine, but not guitar. I have no defined release date for this circuit.

The RMA Mudlark is also undergoing a revision to streamline assembly.

..and finally there is an oscillating fuzz in the works, the RMA Warbler, but at this rate I'm name dropping stuff that is realistically well inside 2018.

Be excellent to each other.

[ibarakishi]

just about ready for mine here soon

[Chankgeez]

..and finally there is an oscillating fuzz in the works, the RMA Warbler, but at this rate I'm name dropping stuff that is realistically well inside 2018.

… waitin' for this one.

Was playin' the Monobius today and the fuzz sounds great on that. I can't even imagine how great the Warbler's gonna sound.

[Eivind August]

..and finally there is an oscillating fuzz in the works, the RMA Warbler, but at this rate I'm name dropping stuff that is realistically well inside 2018.

[ibarakishi]

im really looking forward to this fuzz as well, can't wait until you show a preview of it

[crochambeau]

im really looking forward to this fuzz as well, can't wait until you show a preview of it

Does this count as a preview?

Was playin' the Monobius today and the fuzz sounds great on that. I can't even imagine how great the Warbler's gonna sound.

Thanks! I'm happy you're enjoying that, I've been oscillating between enjoying it and seeing nothing but room for improvement. I think the blend is what saves it from going back to the drawing board (beyond the minor tweaks I mentioned above). The Warbler will be an entirely different topology, with the exception of the bandpass filter, so I expect it to have a completely different footprint sonically. Hopefully just as or more pleasing, but there's no way to tell until test runs are underway.

That said, it's not going to see much progress until the Dirty Doper Mk2 is buttoned up and cruising the streets.

just about ready for mine here soon

Yay! It probably doesn't merit mention, but the top boost function on the Tetanus Booster is a result of your inquiry. It works very well, and has an over the top setting which veers into overkill, but here's to three way switches!

:zen:

[jrfox92]

#saved
That schematic is insane, c.

[crochambeau]

#saved
That schematic is insane, c.

#as_in_the_picture_of_a_schematic?



Thanks, that schematic is probably not 100% complete (in terms of component count/placement) and has no listed values, if anyone is crazy enough to try and roll your own it would be wise to contact me first hahaha. The drawing board level Warbler is essentially two similar cascading sections that are: [gain cell > EQ section (selectable intensity) > unfolded fuzz cell] with a (probably completely unnecessary) recovery amplifier at the end and a inductor based bandpass filter doing global feedback/oscillator duty. The patch points in the feedback loop are for Chimera builds (this will become meaningful in the future).

In terms of complexity, this isn't too far removed from the Monobius or Crustacean, and is certainly simpler than the Dirty Doper, that said there's a bunch of experimental stuff tucked in there that may or may not amount to anything. This is what happens when bean counters are not inclusive.

[jrfox92]

#saved
That schematic is insane, c.

#as_in_the_picture_of_a_schematic?

I definitely horde schematics/gutshots whenever I find them online, so yes.

[Chankgeez]

Thanks! I'm happy you're enjoying that, I've been oscillating between enjoying it and seeing nothing but room for improvement. I think the blend is what saves it from going back to the drawing board (beyond the minor tweaks I mentioned above). The Warbler will be an entirely different topology, with the exception of the bandpass filter, so I expect it to have a completely different footprint sonically. Hopefully just as or more pleasing, but there's no way to tell until test runs are underway.

Yeah, improvements are almost always good. I've played numerous revisions of some circuits and most times the changes come at a sacrifice to some of the things I really liked on earlier versions. So, proceed with caution!

My one small quibble with the Monobious is the bleed on certain ring mod settings. That's to be expected to some extent though.

I'm sure I'll dig the Warbler just as much though.

[crochambeau]

Yeah, improvements are almost always good. I've played numerous revisions of some circuits and most times the changes come at a sacrifice to some of the things I really liked on earlier versions. So, proceed with caution!

There will be an updated Monobius in the tourbox, so you'll be able to compare them directly. I'm happy to update any/all Monobius already out in the wild, should it be desired, this would be free of charge (but I'd request interested parties to carry shipping both ways since I'll be covering parts & labor), I can also provide details if anyone wants to mod it themselves.

Main changes have been upgrading to a 4PDT footswitch so I can snub the on board oscillator when it's in bypass (since shorting both input and output of the circuit to ground in bypass was not completely eliminating bleed from the oscillator), and loosening up bandwidth constraints on the final summing section and a carrier section. The latter bit sounds like turning up the presence/reducing negative feedback, and to my ears it levels up the two diode modes that were quieter than the other, evening things. It would be easy enough to switch in and out.

Carrier bleed is part oscillation up the power rails (I'll look into snubbing this on a future revision) and plain old balancing issue, and it's pretty easy to push it over with the gains & levels on tap. I did hand match all the diodes, but they are silicon - which makes a 0.1% tolerance twice as high as germanium. I do have a diode matching rig in the works that should match them quite tightly, but I need to refine the design a bit. Then there's sloppy tolerances from the transformer manufacturer, I'm dreaming about winding my own transformers, and these would be a good place to start since it does not need a high pot test for safety (like a mains or tube output would). That too is sort of a pipe dream at the moment (AKA low priority), but I'm thinking about it..

I find it is easier to get close to null on carrier bleed when both input and carrier levels are in the noonish range, and of course lower oscillator pitch ranges are easier to bury. If the bleed bothers you and I resolve it through a future rev (that does not depart from the sound qualities you enjoy), I'm happy to trade the boards out.

[Chankgeez]

Great info, Curtis, thanks!

Definitely looking forward to comparing the Monobians/Monobii/Monobiuses (whatever the plural of "Monobius" is).

If I like the revised version well enough, I'll probably save up for a second one rather than updating the one I've got.