m00dawg

BAM there's the math! That should make things easy!

Ah good points, TK! Didn't even think of using wavetables, that's actually very clever! Samples are great! I'm happy to share mine, although, sadly, my synths are packed as I move this weekend. So I won't have anything by Monday (at the earliest) either. While we're talking about Dubstep, anyone have any thoughts on how to do the BZZZZEEEERRRRR resonant slide thing I often hear? (Skrillex does that a lot, which, honestly, is about the limit to most Dubstep I like).

+1 and, once I move and have money again will be willing to donate beers :) I, too, have been trying the wobblebass and, in fact, will be using it something like that in one of my bands songs coming up. I couldn't get the wobble to sound quite synced up the way I wanted though - triplets would probably help out a lot I'd imagine.

I thought there was an Eagle library for circular LEDs on the wiki but didn't find out. With a bit of math, you could figure out the angle of the LEDs and positions. Eagle allows you to specify both absolute positions and angles so you could do it that way. I would consider making an Eagle library for it so you can just plop down your LED rings into your schematic for however many you need. That way they will at least look the same. Failing that, you can find LED rings as pre-built parts. Not as fun, but seems like they work - I haven't tried them though so I don't have any specifics on where to go to find them. But I know they exist :)

Sounds very cool! Curious as to how you are doing all that? I see your right hand is almost constantly turning an encoder or something like that? I have never seen Machinedrum in action that I can remember so curious how it works. And yes, as Antix said, she does have a lovely voice! Her voice with the deep bass is a pretty cool sound.

I would but I'm actually in the middle of packing and will be moving this Friday so my rig is in shambles right now. If you can wait until next week I can get that for you though, sure. In the interim, can anyone else help him out?

True although if there are no downsides to using them for lower speed circuitry, I figured I might as well. It makes laying the board easier and it avoids wasting a bunch of copper to an etchant.

Aha gotcha :) For what it's worth to the conversation, a colleague from a local hardware group I'm apart of pointed this out. Has some good design tips for using power planes and other good tidbits to remember (I realized I had a some of my clock traces for my SRs on the top plane instead of my ground plane which isn't ideal as one example).

Is that a ground or power plane? Ground planes tend to be pretty common. Power planes seem to complement a ground plane (for the desired) impedance and capacitance effects). Although for a single layer board I guess it could go either way for which to use. I usually use ground planes almost all the time. This power plane stuff is pretty new to me though.

As best as I can tell, it's to control impedance and has some capacitance like effects. It can be both a pro and con in terms of noise though but I'm not sure under which circumstances that would be. Beyond that, it's easier since you don't have to route traces. Plus, you generally have a wider area for the power to travel across in ways that would be difficult to do with just normal traces (same sort of deal as for a ground plane).

I can't recall any designs here that make use of power planes (may just have not noticed) but I was curious as to what the use case might be? I'm a little confused, for instance, how useful decoupling capacitors end up being when using a plane. It seems like a pretty clever idea but since I don't see if often used in designs I've seen, and since I haven't found too much online about the subject (from Googling anyway), I thought I would ask. Thoughts? By the way, sorry for all the Design Concepts posts! Sure am learning quite a bit! The help is much appreciated!

Distortion when playing multiple notes using a filter tends to happen even with normal SIDs so that might not be anything to be overly concerned about. I think you were on the right track with sticking with non-filtered polyphonic sounds in your testing. Your PSU modifications don't seem out of the ordinary - if you are supplying DC current, you could bypass the rectifier. I would, however, recommend you simply get a power supply that works well with your Sammiches instead of trying to work around that problem. How much is a new wall-wart? How much is a SID chip? Exactly.

Those music videos are pretty awesome! Really liking the tune in the second one as well. Nice job!

The second one should work just fine. I'd have to look at the schematics again but I think you can put in C5 and get the added benefit (if you wre going above 100mA for instance). It shouldn't hurt anything, anyway. EDIT: Correction: C5 won't really help because it's before the voltage regulator. So you can populate those components but they won't add any benefit (but won't hurt anything either) unless you make modifications.

Here's a better version of the 8x8 Standard LED Matrix and of my SR daughtboard. I had the wiring backwards for the LED Matrix, which would be probably easy to fix in software but I wanted to stick with a drop in solution for folks trying to go with standard wiring (at least for the LED matrix itself). So that is fixed and I added some nice labels to make it easier to hook it up however you might want. The SR board is, well, I feel like it could be simpler than it is. Thought about using standard DIP SR's instead to see if it would make things a bit cleaner (fewer vias maybe). I am using SMDs for other boards so I figured it might be better to use SMDs for this one too. I will likely order both boards soon but I'm moving in a week so I will probably have to wait a few for things to settle down. I'll be using DorkBot so I'll have a few extras of both boards if anyone wants to have whatever I end up not using (if I don't screw up, I'd only use one board of each :) ). As for the full bulk order, I'll let things float for now but given the interest the best option is to just buy the board from DorkBot and split the costs.

Awesome! Thank you both for the advice!

I have a similar spec sheet (I think from TI) and yeah it's very similar. I noticed the range is -40 to 125C which I would obviously be within. Didn't know how that accounted for airflow but I'm guessing since I can't find it in the spec sheets that it's probably a non-issue.

I am working on creating a daughter-board for my LED Matrix which will include the shift-registers for the buttons and LEDs. But I'm having trouble getting things to work well if I put my SMD shift registers on the bottom of the board. I wanted to do this so that the SRs would not be sandwiched between the LED matrix board itself and the daughter-board, mostly due to worrying about heat. Would heat be that much of a concern in this case? And, if so, could I just use transistors to avoid that problem? I was thinking no since some heat will be transferred to the ground (and, if I have it, power) plane and it's still small levels of current. But wanted to make sure before I called my design good and ready for prototyping :)

If you are using the standard CORE, it includes a power section that is used to allow various types of power to be supplied to it and still end up with the proper voltages and things to the microcontroller and things. Basically the components allow for AC or DC to DC conversion. That comes at a cost, which is voltage drop (and heat) which means you cannot simply run 5V through these components and get 5V back. The J2 header is placed directly after all those components so is either a stable 5V output on your main CORE board (which has the power section) or can be used as an input for other CORE boards. You just avoid populating all the power stuff. For CORE, I don't think you have to bridge anything for that to work (for the SID boards you do, last I checked). As far as current draw, if in doubt, it probably won't hurt to mound the power cap (C5) to your periphery CORE modules. I don't think it will draw more than 100mA though if you are just using it to interface with MIDI (I could be wrong - haven't tried it :) ), though.

That sounds like a job for MB-SEQ :) In fact, I would check out the whole BLM sub-board since that is a large part of what those are used for. I don't think you can combine MBSEQ with MBSID on the same PIC but you could either just put them in the same box and connect them internally; or you could just get some ideas. The MBSID firmware should allow for being able to define buttons to play notes and things (I think).

Good luck! On the topic of buttons, though you might not want to put them on multiple rows in a grid, you could stagger them so that they still line up to the proper place on the LCD. Might be useful if you are going to use very large buttons. If you want to keep it simple, I would recommend using the 6x6 tactile switches that can be seen on the ucapps MBSID control surface reference designs. They're cheap and easy to work with, although you can't really put caps on them. For an MBSID control surface, though, I think they work fairly well, especially since there's lots of buttons and things on the full blown control surface.

Hey thanks, Imp! I took your idea and ran with it a bit by using the other operators to add a bit of fill. Sounds more or less like what I was thinking. Note that it loops by accident - the sound is in the first little bit. I think I can probably export the patch since that part of jSynthLib works if anyone wants it. FM_Explosion.wav.mp3

Sweet, thanks nILS! Fired it up and it launches though I wasn't able to get the sammichFM to respond much. I'll keep at it though. At least I can see all the knobs and stuff this way :)

Ooooh yes that could work, thank you!! Is it possible to slow it down so make a longer (and lower pitched) explosion? If not, I could just do multiple explosions :) I, too, am having trouble with jSynthLib :/ EDIT: Forgot to say thanks :)