See MBHP->MIDIbox SID->Step B and Step C for further details. 
Best Regards, Thorsten.
Man, Thorsten is so fast, I can hardly type “Thanks Thorsten!” before I feel I need to type it all over again! ;)
What Stryd Said 
: :
exciting times… ;D
gonna be soldering my dual sid board today! yippey! ;)
excellent work T!!
\dan
Can´t wait to start build again…
Right now i´m middle of changing flat so everything are in boxes..(Not midiboxes) 
But now I have something to look forward to. ;D
Christoffer
Thank you!
I’ve good news: I found out the trick how the original C64 power supply unit shifts the 9V AC to a higher voltage level in order to power the SID. It just adds the 5V DC via a 1N4001 diode - this DC voltage is not used to power the C64 logic…
Schematics can be found here:
http://www.ucapps.de/mbhp/mbhp_sid_c64_psu.pdf
http://www.ucapps.de/mbhp/mbhp_4xsid_c64_psu.pdf
Note that the ground connections have to be wired like shown above in order to avoid 50 Hz buzz on the Audio Outs.
Next step will be the integration of 4 Audio Outs, a USB plug and a second MIDI In/Out into the C64 case…
Best Regards, Thorsten.
i don’t know if this is already asked… but is there the possibilty for you, (in the future) to implement a “Multiple SID” unit controlled by only one core?
Hi Matteo,
possibly yes - I’ve programmed the MIOS based firmware in a way which allows me to use all algorithms with multiple databases, so that another SID could be driven in parallel - in theory. But in practise I expect some effort for the details. First I want to finish all the planned features and projects before I do such a step.
From my personal point of view this is a low-priority task
Every additional core module just only costs about 20 EUR
As I already built the 4-core solution, I don’t need it for myself, it would only be some kind of sport to demonstrate the power of the PIC18F…
A PIC18F core which drives 2 SIDs will not be able to handle the control surface in parallel (due to RAM limitations). And controlling SIDs without the control surface makes no fun. So at least two cores would be prefered anyhow.
So in fact, please don’t expect a release this year.
But if somebody else with programming skills would like to modify the application for this option - step forward (I can provide some more technical details if required)
Best Regards, Thorsten.
Fast, faster, TK!!!
Just build the case this weekend for my 4xSID and designed the frontplate in advance.
Coming back here: Tadaaa! Man, thats timing. Really BIG thnx!!! (again… Â ;D)
/edit: Am I right that the open DOUT Pins are just multiplexed for the LEDs of the Modulation Matrix? Just cant wait to solder that stuff…
Yes, the last two shift registers of the DOUT chain are reserved for the modulation matrix. I just have added the 56 LEDs to the schematic (I’ve a nice animation in mind which could be showed during the startup phase ;-))
http://www.ucapps.de/midibox_sid_cs/mbsid_dout_default.pdf
Best Regards, Thorsten.
;D Rollin!
My drill bits have been in overdrive last cpl o days
*grin*
This is just a link to an article which describes the SID CS handling (so that this info doesn’t get lost)
http://www.midibox.org/cgi-bin/yabb/YaBB.cgi?board=news;action=display;num=1056228123;start=15
For that startup phase:
Hehe… Â “SID rulez” scrolling on those 56 LEDs or what? Â ;D
Hey, TK: Is there something like a Pan Control planned for the single SIDs? Something digital?
If not, I will build some additional analog pots in there to control the pan of every SID (since this is not much additional work). Then I just cant save those settings. And something like a Pan controlled by a LFO or so is always great (especially with 4 SIDs ;D).
Pan control will be possible with the AOUT extension
In the meantime I’ve revised the PSU circuit for the best signal/noise ratio. No 50/60 Hz hum and no digital HF noise in the background anymore.
http://www.ucapps.de/mbhp/mbhp_4xsid_c64_psu_optimized.pdf
Results:
- no heat source within the case anymore, since the +5V are regulated by the external C64 PSU
- 6581: -76 dB signal/noise ratio
- 8580: -90 dB signal/noise ratio (CD quality!)
Please don’t ask if your own PSU variant brings the same results - it was a long try and error session until I found out this solution
Best Regards, Thorsten.
unbelievable! ;D BTW TK, the new mb sid page is very nice, I like Ian’s pile of c64’s, but I’m not sure if I can cannibalise my old c64 :'(, but then again…
BTW, what is wavetable synthesis? is it loading a waveform into the chip or something? (If this requires a long explanation, then just tell me to look on the net somewhere!)
Hi Steven,
the term “wavetable” is an artefact from the good old C64 days. It has nothing to do with audio samples, but with CC controllers which are played sequently - so fast, that the resulting noise sounds like a new waveform. There is a lot potential in this kind of synthesis, especially when you are able to control any parameter (not only the pitch, the waveform, the sync/ringmodulation switch, but also LFO/envelope/filters and also the wavetable CC assignments and the rate — really any parameter) like with the MIDIbox SID
Here are four short preset examples:
http://www.ucapps.de/midibox_sid/mbsid_wt_demo.mp3
First three sound patches: the wavetable rate (speed) is varried from 0 to 119
Last sound patch: this is one SID playing one patch - it should demonstrate that wavetables are not only usable for C64 like drum sounds.
Best Regards, Thorsten.
Good work TK Very nice panel as well!
Can’t wait to get home and listen to this mp3
oh and you should switch to OGG hehe
just one little question …
Can we build the SID step C with just only one SID to begin ?
the firm will be ok with that ?
thanks