m00dawg

*shrug* You can't please everyone. If you're lazy, look at the thumbnails then. I much prefer the larger images and, in fact, I save them to my desktop so I can open them in a viewer. Slightly annoying perhaps but I get to see a really nice, high quality picture. For someone who has rather poor vision, I am quite grateful of large images.

Indeed it looks awesome (and I appreciate the larger JPEGs personally). Looks really awesome in those colors too. Been thinking about what color scheme to use on mine, among other things, and this configuration was on my list. Good to know it really works out well (although I think I'm going for a blue panel with green or amber LEDs myself).

Uhh so? I was totally staring at the logo anyway...err...hmm..wait she does have broad shoulders...

Kinda can't believe these are it. The schematics for these things are online somewhere right? I mean, technically, if a fab wanted to make more, they actually could right? Not saying that'll happen, just curious. Brings a new importance to SwinSID though (although I thought that was a cool project even if SIDs were plentiful).

For the forums or in general? I use OpenID stuff. Works pretty well - I just wish more sites used it (including my own, but I'm too busy/lazy to implement it myself :) Pretty neato idea, though.

Yeah those seem more economical. Thanks for the tip! I didn't realize Alesis, Edioral, or Tascam had firewire units. Guess I haven't been looking hard enough :P I also found this guy, which is pretty tantalizing: http://alesis.com/mastercontrol That is pushing $800, but it looks like it would save me the need to lug around a MIDI mixer/control surface as well (for Traktor) and I could use it as a standard DAW/MIDI/audio mixer at home. As much as building my own mixer would be fun, this seems like a pretty good deal all things considered. Motofaders FTW, although I don't think I can swallow the $800 pricetag anytime soon. A cheaper option though was this: http://alesis.com/multimix8usb20 It doesn't have a MIDI mixer or anything like that but is much cheaper. Thing is, though, I heard USB audio devices suck hard (hence why they might be so cheap?) The firewire version isn't too much more, though. Some things to think about anyway. Thanks for all the help everyone!

FW 410 seems a bit extreme. Who needs 10 outs with only 4 inputs? Or maybe I'm not getting it :) Good point on the suggestion though. I had previously looked at M-Audio and I guess didn't think to search anywhere else other then maudio.com for prices - I was able to find an FW 1814 for a good price: http://pro-audio.musiciansfriend.com/product/MAudio-FireWire-1814-Computer-Recording-Interface?sku=709201 I think that might work, although I guess M-Audio stopped producing it as it's not on their Firewire page on the website and I ran into at least one review where the user had trouble getting to work on their Mac (*cough* I call PEBCAK *cough*). I also have been recommended MOTU. It's weird. Their Firewire audio units are noticeable more expensive but their MIDI boxes (assuming I don't build a GM5x5) are noticeably cheaper than M-Audio. *shrug* Anyone have personal experiences with these guys? Are they worth the price?

I've actually have quite a few pet projects, including an MB-6582, as well as wanting to build a MB64 to use as a standard MIDI mixer as well as a DJ console for Traktor. Trouble is, in order to do Traktor, I need to use my laptop (MacBook Pro particularly) and, if I do that, I might as well just switch over to using my Mac for music makins too. Trouble is, it's a laptop so I need to get a firewire of USB breakout soundcard/box. But, jesus, these things are expensive. And I can't figure out why - I have 2 M-Audio Audiophile 2496 cards and they cost me like $60 (used) and $79. Breakout boxes seem to be pushing at least $300 and, in many cases, with fewer in/outs. I'm just not sure why, either. So, long story short, does anyone have any suggestions on good FW/USB boxes that don't suck but also aren't so expensive I need to sell a kidney to pay for one? Hard task, I know :) I basically just need 4 inputs (2 stereo) and 2 outputs (for Traktor, one for headphones and one for mix out, as well as when doing audio bouncing). Having like 8 stereo inputs would be awesome so I could input all MBSID inputs but I can live without and do mixdown when I master if I had to. Comments, good or bad, certainly appreciated :)

Haha well good point. If you're using a wall-wart then it's hard to use a fuse on the main-side of the transformer. I always went without but I also broke at least 2 wallwarts and a C64 PSU supply (I'm sure it's a fuse, but I'm not going in through all that epoxy to find out :). I guess my point is to be a little more careful when dealing with a non-fused supply.

I should point out too that a fuse is good for testing (accidental shorts, that sort of thing). In fact, you could use a few if you're building your own PSU. They're generally cheap, and can save your components (and/or your transformer).

Ah right. I forgot he'll cut panels from the PT-10 (which has screw-holes). I think another MidiBoxer also made an MB-6582 with screw-holes. Sounds like Doug has a pretty clever solution either way. Hope he's doing better (I know he was donating bone marrow or something along those lines?).

So I've opted to throw in the towel on putting my MB-SID inside a C64 case - at least for now. I've got a limited time to finish some of my projects (baby on the way!) so I've had to put a few ideas on hold. So, I plan on making a more standard MB-6582, but with a few modifications. One, I was curious as to if anyone has drilled screw-holes on the front panel instead of using JB Weld. I thought I saw an MB-6582 on the forums where someone did that but I can't seem to find it after a good bit of searching. I figured this would end up being easier and, really, I don't mind screws on the front panel as long as they don't get in the way (I think it could be a good look). Second, I'm sure some of you have seen my posts about struggles with building my own PSU, but that's still the route I want to go. So, I'll be feeding the MB-6852 +9, +5, and GND via J4. I'm assuming that, with a bit of cleverness, I might be able to use the standard DIN connector and bypass and bridge things. Instead of doing that, though, I was thinking of just modifying the rear panel to accept a panel mount DIN connector. The only way I can think to do that is to remove, or shorten, the 25-pin D-SUB for extensions. I was curious as to what those who are working on, or have finished, their MB-6852's thought about that? I actually wanted to panel-mount everything (so I could potentially use the mainboard in my C64 case when I'm ready to do that), but I think that would be more trouble than it's worth. I've got most of the parts already here or in the mail, with the only outstanding issues being rotary encoders, knobs, and, of course, having the panels machined. Thanks all!

Brief update - I received the printed boards from BatchPCB and thought I'd see if I could at least replicate some of /tilted/'s findings. Sure enough, I end up with around 3VAC off the center tap to the GND (the - on the rectifier) which seems to indicate it is quarter wave. As I mentioned before, while I still want to eventually tackle this, I think I'm going to work on a more standard setup so I can power my MB-SID and finish that up. After that I might circle back around and see if I can make this design work.

You can always bug him on his MySpace page. At least he didn't disappear off the face of the Earth or anything.

Trash80 is awesome. I'm a fan of 8bitpeoples.com in general (although some of the musicians are a bit too experimental for me).

Ah well I actually tried doing that very thing in an earlier design and somehow ended up with the same voltage after both rectifiers. I did run that design through the simulator and ended up with weirdness too. Specifically when tying the negatives together. I can have another go at it though.

Yep, the 47uF between two 100nF caps after the regulator output. That was suggested in the multi-tap psu discussion. I don't have this setup on my current power board (which is on a protoboard) but plan on getting a nice printed board out of this and have plenty of room for caps if I needed them. I figured that tantalum here might be better at filtering here, either in addition, or even to replace one of the 100nF caps. Having it explode could be bad, though :) However, since it's after the regulator, something would have to go seriously wrong to get the voltage up to 25V I'm guessing. That said, if I can get the same filtering ability (or better) using other caps, I'm find with that. Tantalum seemed to sort of kill two birds with one stone.

That was discussed, but not in great detail. I wasn't sure how to derive GND, err, unless you're talking about a true multi-tap transformer (as opposed to a center-tapped one). I've been having a hellofa time tying to find a multi-tap that can output multiple voltages and don't see a huge benefit over, say, a dual secondary transformer over a single (as long as it is rated high enough). My current thought is to just use a regular 9VAC transformer, rectify and regulate that down to 9VDC and then hook another regulator up to that to step down to 5VDC. I've done that before with success and, apart from heat, it seems to work reasonably well (though I haven't used it to power a full control surface yet).

Why do you think aluminum is better for DC filtering? I was under the impression that aluminum electrolytics were rather poor at filtering HF noise. Seems like tantalum is quite good at that and gives you larger capacitance. Given that the ones that can handle higher voltages are somewhat expensive (and their intolerance to voltage spikes), I wouldn't put them before a regulator. They might be good after, though. Anyone have any further thoughts about these guys? Been thinking of replacing my 47uF cap on my PSU design with a tantalum in hopes I can get better HF filtering (the PSU will be powering an MB-SID).

Can you elaborate on that a bit? Are you saying that can be somehow used to produce 9V as well as 5V? You'll have to forgive me, here, bipolar supplies are something I know little about. Speaking of, if someone knows of a good source for reading up on this that would be awesome! I know there's good Wiki articles on how to build one (they've already been sited in this thread) but I don't really understand the difference between positive and negative DC voltages, other than the absolute basics.

Thanks for the explanation on the notation, stryd! The sweet spot could be a possibility. I'll need to see what voltage I'm feeding it, although /tilted/'s findings also explain things. I probably am feeding it more AC than DC given that I have no diode off the center-tap. It's also weird that the voltage continues to drop in proportion to the load if I found the "sweet spot"? I'm going to be bringing this issue up at my local hardware meeting next Monday so maybe something will come of that since I may have access to an O-scope. *shrug* Either way, this is a really fun exercise in basic power supply theory :) At least I'm learning something from all of it :)

I know this is a silly, and probably basic, question, but how do I read "6V3DC", "12V6", etc.? I assumed it had something to do with the center-tap, but I'm especially confused by "0-6V3-12V6" ? As for the regulator dropping out, I don't think that's my issue - or, if it is, it's dropping out and coming back in rapidly, which may be produce the lower voltage (someone mentioned that in an earlier post in this thread, but I can't seem to dig it up). Otherwise, I should be getting close to 0V off the regulator, not 4.3V right?

@/tilted/ Actually the 9V bogs down too I believe, just not near as much. So if I'm doing 4.5V, the 9V is around 8.98V or something around that. It's definitely more stable than 5V. I can hook the board back up and run another test to see if you need concrete numbers. @seppoman I did that so to make the traces easier on the board. My apologies for the confusion there. Center-tap is X1-3 in the schematic I posted last.

Hmm...that's interesting you mention that because the problem I have been having with this design is that, the more power it pulls, the less voltage I get. I also get a lot of AC hum. Seems to me that crazy ground explanation you gave previously may be panning out? I'm not sure though. As for using two bridges - I tried that and failed :) I was never able to get 6V and 12V (it was just one or the other) when using two bridges. I have no problem using that approach, but how do I hook those bridges up with the xformer? Can you even do full-wave rectification this way? Do they both share the same outer-tap (which would be GND) or? I tried multiple times doing it this way so any help in that regard would be appreciated.

Haha I wouldn't call it the best option by any means :) Just another option. Some people really jones for the C64 PSU, some prefer wall-warts - it's all about preference and choice I figure.