m00dawg

Wow that sounded awesome, although it just about scared the shit out of me :)

Thought about a 7" and, in fact, there are some songs on the album that could work well as singles. The cost savings was about $250 from what I found. I really like the idea of really accentuating the album, though, and since a 7" will only gie us 2 songs I was thinking the extra $250 might be worth it for an LP. Can you elaborate on the silkscreen route? I noticed that the costs of the whole thing went /way/ up by having artwork, although artwork is, to me, part of the whole vinyl experience. So I want to have it done in some way.

Oh hey thanks! I really like our sound. It's not something I would have done solo and the combination of surf and chips is surprisingly cool (subject to opinion of course :) )

Wouldn't it!? Sadly, it's pretty damned expensive to do vinyl for a band like us. Doing a run of 100 12" LPs is around $800-1000 - that's without any artwork (which, I mean, is part of the whole point). That could buy us more equipment to make better music :) But we're going to try anyway! We might see if we can do something on Kickstarter or something. I have this unhealthy fascination of what our music sounds like in vinyl - or really any chiptune-like thing. I wonder how the sound changes as the record wears, for instance. Do the square waves start to sound slightly more rounded? Stuff like that.

My band (Vicitm Cache) just finished our latest song off our forthcoming album called Chipsurf Pipeline. I thought I would share this here since it uses the NES (2A03), OPL3 (via the sammichFM) and the SID (via the sammichSID) for sound effects. So far, it's my favorite tune (finished or otherwise) off our album. Anyways, you can listen to, download, or buy it it from our website. If you do opt to throw down bling, it will likely go towards saving up to do a vinyl release and failing that, towards more chip-synths :) But just listening or downloading it and telling your friends if you like it makes us happy.

Yup!

Yep I think you'll be happier for it. Even with a variable iron you can do bad things though :) You'll have to figure out what works best, but I keep mine midway (at 3) most of the time. I crank it up to about 3 1/2 when I'm desoldering. As far as the board goes, my sammichSID has some uglies on it - I had to end up cutting tracks to figure out where a short was. I had to fix it using one of the end legs I cut off of a part and soldered between the cuts. It looks a bit ugly but it works. And my first attempt at the MB-6582 resulted in a huge headache I still have yet to fix with hooking up the control surface with the mainboard. I opted to just start over and make my own control surface (not just because of those issues but more because I wanted a rackmount version that had room for SSM's and fun stuff like that). *shrug* You live, you learn!

You'll definitely want a temperature controlled soldering iron and station. There are high dollar ones out there but I found a decent Weller at Fry's. It couldn't have been over $60, though I've had it for a while so I don't remember how much it cost exactly. It is not temperature calibrated (as in my dial has numbers 0-5 instead of actual temperatures) but it's /wildly/ better than the Radio Shack one I was using. Here's the thing - how much are those OPL3 chips worth to you? To me, they are damn near priceless so there's some serious justification for purchasing a good soldering iron and some of the other essentials (a good flat tip, a pointy tip for SMD work, etc.). Soldering became easily 10x easier with a temperature controlled iron so, again, I HIGHLY recommend one.

Yes you can do that. Also pulling pads shouldn't be a common occurrence - you might want to consider turning down your iron to see if that helps. Also, I find solder wicks far less useful than a solder sucker. You can pick one up from Radio Shack for $5-10. Your mileage may vary but I have found them wildly useful, particularly if you cut out a small notch on the plastic tip to fit the iron in. You could also try to solder on the side of the trace if that side doesn't have the lifted pad (or the pad isn't being used to connect a top trace with a bottom one).

R65 looks to be going into the ground plane which is why you don't see a trace. That's what it looks like according to the schematic. R58 does not, however. The solder in the small hole is not a problem - it's a via so it's basically bridging a trace from the top of the board to the bottom. In other words, it was already connected anyway so adding solder won't hurt anything as long as the solder isn't causing a short (touching another hole or component). Because R65 appears to go to ground, if that's the lifted pad, you can use a wire on anything that is part of the same ground plane. The other pad connects to R69 so if that pad is good, you could solder the wire to the leg of R69 on the same side.

That description is unfortunately not very helpful without pictures - if you can provide at least the resistor number from the board you might be able to get better help. That said, what Hawkeye is talking about is to follow the track where the resistor goes and to use a wire to solder the resistor somewhere else. This could involve scraping the solder mask (the red coloring) off the top of the trace enough to see copper and solder the wire to it, or you can often solder the wire directly from the component the preceded the pad you lifted, thereby bypassing the area. It won't look exactly pretty but it works and you can probably solder the wire and resistor on the bottom-side of the board so that top still looks relatively nice (other than the lifted pads). Hope that wasn't too vague but well, you asked a vague question :)

Yeah a spectrum analyzer may help there. I find myself using the one in Live a lot more, particularly when mastering, so it may show you what's going on. Thinking about it, you could always filter it out with EQ if you don't mind losses in treble but it's generally nice to know that isn't required as a default option, particularly if the high pitched noise is in the audio band enough to affect things (such as noise drums and such). If you do some searching on the forums, you'll likely find a few flamewars over whether or not switch-mode is really that bad or if it's Satan himself being resurrected through audio. The best advice I can give is do some research (including the audio tests like you are doing) and form your own opinion :) I will say that for the Sammich kits, since the power supply requirements are simple, linear is still probably your best bet. Switchmode tends to be discussed more in a practical sense for the larger projects that need a series of voltages, such as the MB-6582 or when using SSM filters and other fun things. In those cases, switchmode tends to offer multiple voltages in smaller packages than a linear supply and with a lot less heat. Sort of an aside but I thought I'd mention it anyway.

I would describe it as transient noise that comes from the high frequency noise in the DC power output itself. The noise is caused by the high frequency circuity that is acting like an on/off switch flipping the source input on and off rapidly to end up with the output. It's a very efficient process - much more so than linear PSUs. They can also handle a wider range of input voltages because the switching circuits just switch at different rates depending on the input to produce the stable output. The trade-off is that what you really end up with is a bunch of pulses on the DC signal that look like a certain voltage overall (say 12V). Think of it as a somewhat ugly high frequency square-wave of sorts. The problem here is that the high frequency noise this creates cannot be totally filtered out without using capacitors that are built to dampen HF noise (such as tantalum). These can be both expensive, some say dangerous (I tend to disagree), and a bit of a black art. From what I have read, ceramics can reduce HF noise but this comes at a price. So you have to end up using various different types of caps. In the end, capacitors are not perfect and you may need to use quite a few to remove the noise, or may not be able to remove all of it regardless. Linear PSUs do not have this problem as the noise they generate is typically easier to filter out and it's usually HF (though I think if you have HF noise coming from the AC side, you may see some of that on the DC - not entirely sure though). All that said, if you're not hearing the noise, it could be too high pitched for your ears - either because you went to too many concerts without earplugs :) Or because the switching frequency of your DC supply is above the audio range (say 1MHz). In those cases, the noise is likely there but you and your audio equipment can't really pick it up. Some might call that a non-issue but I prefer linear PSUs just because I don't want HF noise of any kind in my audio signal, regardless of whether or not I can hear it. Plus I find them more interesting. TL;DR If you can't hear it, it's probably ok.

Ah that's good to know! I myself don't (yet) need more than 5 ports, but they are slowly starting to get filled up :)

It might be helpful to know your goal for doing that? If it's to have access to all those MIDI ports, you could just look a the GM5 or GM5x5x5 projects. The GM5 is basically a USB to MIDI bridge (with up to 5 MIDI In/Outs) that has pretty kick-ass support for OS X and Windows (haven't tried Linux but it supposedly works well there too). So each rack could have one of these guys (or two, whatever you need) and you can just run them back to a USB hub to your computer or whatever device you might be using to control all that. I like the GM5 especially because it's easy to name ports (on Windows anyway - haven't quite figured it out in OS X) to make it easy to find your synths. I find it hugely helpful since Ableton Live doesn't let you name ports (it uses the drive name). Plus, it's fairly extensible. You can make a 1U rack pretty easily with the GM5x5x5. The only catch is you may have to wait on the bulk order - not sure what stage it's in but last I checked it was getting pretty close to having enough people to go ahead and do an run of these guys. They rock and, unlike most DIY projects, this one actually seems to be cheaper than commercial variants, but either way, is much better in my opinion by way of configurability.

I have a feeling he was still being sarcastic :)

Very nice! +1 I'm always impressed when someone is able to stick a keyboard on these and make it look pro and you sir, have done that. Solid work!

Ask and ye shall receive. The album isn't done yet but I put up another song off the album that is complete and ready for your ears! Songs are available for free off the site (just put in $0.00 for the cost), but if you get them for free, help us out by spreading the word if you like our music!

The MIB-6582 uses a passive mixer, a design which I melded together with the CMoy audio amp design. You can find my (untested) work on the =sidr8tr]wiki. It probably works as it should but I haven't reached that phase of my synth build yet so use at your own risk. You need a bipolar supply, but I was going to have one anyway in my design since I was wanting to use analog filters as well.

That's usually my favorite option, though for the Sammich I didn't want a huge power brick as I can't build my own PSUs smaller than a commercial solution. Plus, there's that epic thread about adding circuit protection stuff and all that so I figured the Sammich might be best served via a $20 regulated power brick someone else built.

That looks like a switched PSU to me (though I'm having Google Translate fail). You'd want a linear regulated PSU as the best option typically. Switchmode will work, but can induce noise (and usually causes a big flame-war here on the forums about half the time it's mentioned :) )

I don't totally understand the difference in routing the audio signals either (such as if there are any downsides to routing audio only to certain outputs), but I can say that I have done something very similar to what you have done and I did not have any problems. I basically put drums on op34 and regular instruments on op12 and that worked. I couldn't make a guess as to what might be wrong in your case though :/ I would start by using just a single instrument and putting it on different outputs to see if anything changes and go from there.

That is basically just the start of a bipolar power supply, which makes sense since that is part of the PAiA kit stuff and bipolar supplies seem to be common in analog synths. It's super basic - you still need to regulate the voltage down to what you need (+5V and +9 or +12V depending on your SIDs) as well as the extra filtering caps. Basically if you're going to go that far, might as well go all the way. I don't know what your design plans are though so not knowing that makes it hard to suggest a specific PSU options (of which there are many). If you're interested in building your own PSU, or wanting to go with a modern solution, check out thread. It's a rather long thread but covers both linear and high frequency switchmode supplies that should be suitable for audio applications. The debate will probably never end over linear versus switchmode so form your own opinion is the best advice I can give :) Note that messing around with PSUs suggests you are knowledgable enough to know how to safely deal with mains voltages. If that is not the case, I would steer clear of custom PSU options and stick with the standard solutions. Depending on your design, that's probably a C64 PSU or a linear regulated wall-wart. And actually you probably can get away with a wall-wart in most cases unless you're going with something fairly fancy (external filters, fully stuffed MB-6582, custom chassis, etc.).

Adapters came in! The 9VDC works great, though I haven't yet tested temps yet. After a few hours the sammichFM was cool to the touch all around and I felt no heat on the sides (maybe a teeny tiny bit on the right side where the regulators are). This is the one from Jameco that mazatta recommended in post. Wilba also added a link to it on the sammichFM wiki page. I haven't tested the audio noise yet either but I was able to hear some artifacts before that I am no longer noticing so that's a good sign. I bought a similar wallwart for the sammichSID and noticed no difference there - I did do a recording test but not a particularly accurate one.