Razmo

Pascal: Just saw the links to the files you gave... thanx! :D

I'm uncertain of this... the only thing I've found seem to be sysx ifo on MIOS itself, and not the MB SID V2 specifics... I need to know patch request and patch dump strings etc... if any is there at all... I've found for the V1 enginge, but none for the V2 yet...

Hi... this is basicaly for Thorsten: I've finaly made a V2 SID synth here, but as I've not build any control surface I'm set on doing a Sound Diver editor for the V2 engine... I've not been able to find any kind of SysX info on the V2 engine horsten... is this because it does not support this yet, or won't at all? Without SysX capability it's kind of hard to store patches on a surfaceless version of the V2 engine...

Stryd: Don't worry, I believe I've got some browser confusion goin' on here... I'll sort it out! ;)

The 707 and DS-8 both use the same FM chip as the FB-01 ... it's the YM2164. It's impossible to find the datasheet for this chip on the net, though I've got some info on it from the FB-01 service manual. The chip sound awesome, though the DAC is just 10 bit... I suspect this to be some of the grittyness, but still the older FM chips has a lot more warmth in their character... more analog-like. The 707 and DS-8 are almost identical... I've actualy had both of them, and to be honest, the DS-8 sound a slight more warm to me... one of the absolutely coolest features of these beasts is the UNISON feature... they sound SOOOOOO fat! :P Sidenote: Does anyone else in here have trouble logging in here at the forums? ... I have to change my password to get logged in EVERY TIME! ... if I use the normal login procedure, Internet explorer tell me that it cannot read the format of the webpage... and I've reset the whole browser to standard settings to see if that helped... no use ???

Believe me, I've had second thoughts... mostly because I do not know if MBFM have the same gritty character... old FM chips sound more dirty and are good for bass sounds. unfortunately they do not have much storage capacity... but nonetheless, the FB01 casing is ideal for a non-controlsurface build of MBFM... I do not think you can find anything with all these features at the price these things go for on ebay... one is up at ebay pt for just $35. The FM chip used in the FB-01 is the same used in KORG's older DS-8 FM synth... It's really good, and I'd really like to see a project for this FM chip. Also it's not a surfacemount chip.. good old type that go through the holes! ;D ... I believe that the FB-01 chip is the successor of the much used FM chip in arcade machines like OUTRUN... may even be pin compatible with a few enhancements.

Hi everyone :) Yes, I've decided to build a MB-FM because I stumbled upon an old soundcard with the chips lying about at a garbage area where I live... jesus, I don't understand why people throw this away ??? I've read a great deal about the construction, and I see that there are issues with the +/- 12volts for many... I needed to find a good casing, and for some reason I had my eyes focused on an old FM synth by Yamaha I've got... the FB-01. These babies are dead cheap on the used market, and are perfect for this project! it has: 5 volts for digital circuitry +/- 5 volts for analog opamps Build in powersuply with switch 3 holes for chasismounted MIDI sockets (yes they have the right size!) 2 holes for audio outs (could be stereo or mono depending on the MB-FM output config... chasis mount) it's tabletop or half-rack the only prob is the front panel... it has been made for a small LCD display and 8 buttons, but these can be taken out, and covered by a beutiful laminated printout ;O) Of course I'm making a version WITHOUT any control panel. Here is a picture of the device (some call it a "clock-radio" ;D) : Now one thing I hope is that the YM chip on the MB-FM can make as good bass patches as the old FB-01... the FB-01 has a dirt and grit to it that I just love, but on the other hand the sheer amount of patch storage capability of MB-FM makes me want to sacrifice this machine :-\ Here are a (long) demo of some FM bass patches I made on the FB-01 ... hope to be able to do something like these on MB-FM 8) http://razmo.ziphoid.com/FB-01 and 4-pole.mp3 Note that somewhere near 1/4 the FB-01 is run through a Waldorf 4-pole filter... love that sweet sound of FB-01 through the 4-pole :P ... but soon this will be MB-FM -> 4-pole :D

Hi guys.... I'm back again and I want to start joining in on the V2 beta testing... NOW! I'm going to build Wilba's MB-6582 at some point, but until the components will be purchaseable from SmashTV, I'll be building a single-core version with two SID modules to get started. Thus I've got a question for either Thorsten or Wilba (whoever get here first): What type of pot will I need to implement the feedback feature PRECISELY? ... I'd be happy with a direct link to a german/uk electronics site with partnumber that will send to Denmark. I'm not that good at hunting down parts here in Denmark, and worry that I might get the wrong part or something :-[ I'm just building a minimal V2 without LCD and control surface of any kind... I'll be developing a SoundDiver Adaption to tweak it (which I'll release here if Thorsten want it).

Thorsten: hmm... nibbles... well I'm certain that Sounddiver can decode that, just hope it will not pose too much of a hassle... I assume the reason for the format is 8 bit values right? With regards to the UNISON feature, just remember that having a bit of "sloppiness" in the triggerings can add a lot of fatness to the sound... maybe it's worth experimenting with a parameter that will offset the voices by a set amount? ... Another thing (don't know if I've asked this before): Will it be possible to control the oscillators of a single SID independently from three different MIDI channels? ... To me this is very important since NO real synth has this capability that I know of... one of the most used features of the SID tunes from the past is when two channels are playing different melodies, and one is either sync'ed or Ringmod'ed to the other... the melodic clangy results are much of the C64's charm from back then, and something I'd really like to be able to doo.

...and Thorsten: When you have implemented full SysX implementation of controlling the V2, then I'd be happy to make a Sounddiver Adaption for it :O)

Hi again Thorsten! :O) I just thought; this super-poly thing you're talking about, is this a mode that would work just like any other oldschool analog synth from the 80's with 8 voices?... I mean, that you can play the 8SID monster polyphonically vith dynamic allocation of up to 8 voices? (meaning each SID is considdered a seperate voice)... I sure hope this will be possible because that is probably the most useful configuration for me B-) ... I've always dreamt about a SID synth with 8 voices. And about those 1-2 ms... no big deal really is it?... MIDI itself seem to have some latency between noteon messages. In fact such slight variations are what makes analog synths so special... small timing irregularities etc... and IF you implement the super-poly mode, PLEASE PLEASE PLEASE also include a UNISON mode for this configuration!!!!!! ... UNISON is the total joy of older KORG synths, and the more "latency" between voices fired off only add to the magic... believe me! ;O) 3OSC - 8voice unison = 24 oscillator unison!!!! WOOOOOW! :OP BTW. I'm hooked up for the 8SID PCB now, so I'll soon be participating in testing and idears again Thorsten :O)

Hi Everyone... and a special HI to Wilba, and not to Mention Thorsten :) Well... My eyes are still fatigued by looking at that "All in One" project you are doing Wilba, and I definately hope, that these will be purchaseable through Smash TV's website INCLUDING components at some point in the future! :P ... But having always been VERY minimalistic (contrary to many people in here ;D), I have a question: I've always dreamed about a space preserving studio of mine, and are well on my way to having obtained this, and thus, I'm fond of 1U rack things ;D ... so naturally, I'm wondering, if it would be possible to use your All in One PCB in a 1U rack housing!? ... As I'm informed by Thorsten, the new V2 requires the use of pots and buttons since nothing is done yet to have a PC interface!? ... what EXACTLY will be needed (minimum) to actually create this thing in a 1U rack module? ... I got enough 8580's to fill two modules if I wanted to, so SID's won't be the prob. 8) I've been asked to betatest the V2 engine by Thorsten, but unfortunately I'll have to wait untill this 1U rack thing is reality for me, as I'll not fire off money on anything but this in the future, so I hope it'll see the light of day this project of your Wilba in the near future, so that I may utter my ultrahigh synth engine requirements to Thorten and make his coding life a not so easy one to live ;D ... Best regards, and a thumbs up to your project! 8) Razmo, Denmark.

... and also, changing the range like that, would probably ruin the tuning of the filter... maybe the cap values currently used was chosen because they go "hand-in-hand" with the frequency of the oscillators? ... in other words, the filter frequency is easier tunable in semitone steps... this feature is very important when making acid-sounds with high resonance... where the filter cutoff freq must follow the pitch as played on the keyboard. Regards, Razmo

So basicaly what you do by changing the caps, is that you "squeeze" the frequency range of the analog filter. It sacrifice top end, but allows "better resolution" instead as the Filter Frequency range has been put under "magnifying glass" in the low end... so to speak. Nonetheless, this does NOT change the anyway exponential curve of the digital control logic, and thus the special 8580 code I came up with would still be valid for a true linear response curve, though it sacrifice resolution the closer you get to the low end (gradual steppiness). The good thing about "squeezing" the range though is, that as the high range of the frequency (thanks to the digital control logics) is of much greater resolution, so "squeezing" the range does not make a very drastic change in the new max. range value, but greatly does so in the low end (again, because of the digital control logic)... so yes; for bass patches this should not really be a problem. Don't caps come in adjustable versions? like risistors does with potmeters? TK? ... if they do, can they not be used on the boards so that changing the cap values would be much more flexible? Regards, Razmo

In conclution to teh above; I find that it's not the analog filter that is limited... it's the digital control curcuit that has it's limits... to make the 8580 work linearly as the 6581 what you do is that you simply use the same freq. table you use for looking up note frequency values, and scale these values to the right amount of bits for the cutoff frequency register (freq. is 16 bit, cutoff 11). This is why the 8580 filter sounds "steppy"... now TK has made some interpolating code in the engine to smooth out this effect, but since the range of values to smooth between gets lower and lower in the bottom range, you cannot avoid the steppiness in the mighty lowest of register values... Now I do not know much about filter caps, but if changing the caps could indeed make the response curve of the analog filter logarithmic INSTEAD of linear, then the analog filter curcuit would follow the same logarithmic working as the digital control curcuit that controls the analog filter, and the frequency range for the filter would be much much better!... I'll leave that to the hardware techs!!! ;D Regards, Jess.