kokoon

i know about V/oct and V/Hz but i always wondered how the V/Hz works - it would directly translate that you need 4.000 volts for 4kHz ... and that looks a bit funny (dangerous?) - then i also read somewhere about the V/kHz (still linear) - i think it was the WASP synth - so i imagined that the actual V/Hz was used only by the "bass" synths... where the pitches aren't that high. but now more that i'm thinking about it - there has to be some constant - V/C*Hz - so it still remains linear but the actual voltages still remain in normal limits :) :) i should think more.

thats kokoon! ;) no problem about the help though - i this place has been wonderfully helpful to me and i'm trying to continue that spirit!

lasertran is probably the best option but it's not the easiest one. that's why i suggested the self-adhesive transparent foil. you print it, you stick it, you stick another one on top (protection) but yeah, it's probably glossy as hell. i'd hate that too.

MS-20 is V/Hz?!?!?! or is it V/kHz?

you don't *have to* make a "real" (printed) circuit. it's cleaner and probably more durable but i think most people here just keep the breadboarded PSUs. i can post a photo of mine (bottom side - where all the connections are) when i get home but that won't be before tomorrow evening. in short - note that this is my first electronic project ever - i've only made 3 of such boards and this could be all much different from how other (experienced) people do this. i figured this out myself and there could be much easier ways :) 1. first you think hard to figure which component should be placed where to make as little connections as possible. that took me the longest. 2. then you connect them together - according to the schematic - using the cut off legs of resistors and such. and where they're overlapping you use isolated wire. you can also make "jumpers" on the other side so you theoretically don't need isolated wire. but i think it's the easiest to use whatever you need. 3. you use the multimeter to check the connections - according to the schematic. i usually set it to resistance measurement and when i get non-infinite resistance (no conduction) i know that the line (connection) is working. you also double check all the resistor and capacitor values, orientation of polarised elements... everything must be checked before you plug the power cord in. 4. you plug the power cord and measure the output voltages. if all's okay then you've done it. ;) this is my broccoli18 programmer - much less complex - but you can get the idea how the connecting is done. bottom shot: top shot: another top shot:

i don't know what that board is called but it's that cheap yellow board with a grid of holes in it. i think people here call it "breadboard". i think the protoboard is the white one for wire-wrapping. just make sure it has copper solder points around each whole. like this:

that's more than enough to get started and make some patterns. i'll try to make some when i have the time (probably this weekend). thanks alot!

1. you don't really need the led 2. the power socket and the power switch: for de-soldering you'll need a normal soldering-iron (what you use for soldering) and a de-soldering pump (a few euro - probably less than 5 euro) or a de-soldering braid (a wire which attracts the solder very easily - you can buy this also - a few euro) although when i was desoldering my plug and switch off my C64 i didn't have any of those and i managed to unsolder them just with my soldering iron. takes a bit of patience but you can do it.

it's a circuit you make and then you connect the c64 psu to it. i'm also a n00b but i didn't have much difficulties making it. reading the schemes is really easy. -/\/\/\- is a resistor -||- is a capacitor -)|- is a polarized capacitor (electrolytic for instance) the ->|- is a diode but the combination of the 4 diodes in that schematic is called a "bridge" of some sort - but you just buy what it's written there - B40C800. it has 4 pins. you buy all the parts and then just connect them together like shown in the schematic. i used the test board (the yellow board with a ~3mm grid of holes with little copper circles around each). you can get the switch and the connector from a c64. get all the parts and then ask here for further instructions.

if you're making mbsid then it would make sense to make this first.

wow so you actually use the pitch -> freq logarythmic conversion for this? how on earth did you think of this? not that it doesn't work well :) i think i'll stop bothering you now. i understand the resources are very tight and no one should expect you to rewrite anything. you saved 500 bytes ascii bytes or binary? either way that's quite nice. i can't wait for this tb-303 howto though - is the functionality finished or do plan to add antything else before releasing it (along with the documentation)?

print on the A4 transparent sticker foil and stick it on. then you can add another transparent layer to protect it.

wow i never realized that the bottom cutoff settings of 8580 even don't make a difference at all :) now it's all clear to me haha. one more question - is that mapping table hard-coded or is there a exponential mapping function of some sort? i always thought the SID filter register would be 7bit (yeah i know you couldn't have interpolation that way ;) i'm thinking maybe it would be nice (certainly for me) to have a few filter cutoff modes (low, med and high freq)...

*jealous* i didn't get my x0xb0x cause the 2nd run sold out :'( :'( :'(

so it's actually impossible to get the filter over that range without the "step" by any means even outside mbsid? if so - i didn't know that and then i'm really sorry about the whining about the software.

you could do one thing - i once programmed this (not in asm) but i'm not sure if i'll be able to describe it in english: make interpolation speed variable - dependent on the input change speed. that would mean if you turn the encoder slowly then changing physical values can take even 50ms per unit which should probably be enough. i'm sorry if you already considered this and concluded it's too heavy resource-wise. another thought - why should the entire cutoff freq range be used? for my taste the bottom ~10 units are unusable. maybe we could change this ourselves? along with the mapping function that now causes the "stepiness effect"? i'm sorry i'm making such a big deal out of it but smooth filter sweeps are the most important thing for me :) ofcourse if nothing can be done then so be it.

bridges: if you're bridging on the copper side (conductive) you need isolated wire. in your case you're probably bridging on the other side so you can use the cut-off legs. i don't know about the bypass cap - it shou work without them too but it's apparently best to put them as close to the IC as possible. but let someone else answer that one :) midibox is my first ever electronic project so i'm a total n00b.

and then you'll need midiox to patch the virtual cables together. it's easy if you know what you're doing and if you don't know then ask here after you've installed both.

i'm building mine into a small silver suitcase. later i plan to add a MBFM and a MBSEQ in there too. in the lid of the suitcase there will be mbsid and mbfm (each one half of the total lid height) in the bottom (base) part of the suitcase there will be the mbseq. it will be very very tight and i'm having a hard time squeezing it all in but i think after i get the mbsid in all the rest will be trivial (i'm planning a 4xSID version and that's like 13 boards!). though the mbsid will reach quite a bit into the mbfm area but the frontplate will cover that. and the mbfm is only 4 boards so it will work out. by milimeters though :>

i'm a total n00b, this midibox sid is my first soldering ever but i already managed to almost finish it. and i got the optimized psu right in the first try :) i just did everything exactly like it says in that pdf. though it took me a hour or so to place it all on the breadbord (or whatever it's called - the plain board with a grid of holes and copper rings/circles around them) - not on the stripboard.

it's all written in the pdf that's linked on the ucapps.de sid module page. the difference is HUGE. no background hum at all! the sid quirks still remain (hanging notes, funnny filter switching behavior you mentioned) but still - it's absolutely usable now! especially the 8580. you *absolutely* have to do this mod!

if your core is sending the "heartbeat" sysex then you're okay. load the appropriate application.

excuse me but where did you get that combined PSU? that could be ideal for powering a MBFM? 5V DC and +12/-12 AC bipolar?

i made this last night and i can't believe how much difference it makes! i haven't measured the SNR yet but on 8580 i virtually can't hear any noise at all! big up to you TK!!! this synth really is taking it's shape.

you'll need some virtual midi cable ala hubi's loopback