Rio

The solution is decribed in following thread: CEM3378 Schematic

Now i've solved that problem of swinging background noise: I'd measured a frequency of 700.000KHz on a oscilograph, which was produced by self ocillating of the TL072 and which modulates the whole audiosignal dramatically. For example: if i put my fingers in the near of that TL072... the whole audio signal was swinging... So if you want to build this schematic above, please don't connect all that ground wire to external c.v. inputs and audio signal inputs (add only one single ground connection between both PSUs directly and a direct connection to that board) and add a pair of capacities (2x220pF) parallel to the 22k at TL072. That schematic will give a negative-feedback condition to that disturbing high frequencies. Schematic: 22k +-----/\/\/---+ | | | 220pf | +------||-----+ | | | |\ | --+----|-\ | | \_____| | / -------|+/ |/ That should solve the self oscilation of TL072 and provides a clean filtered sound. (for people, which are interessted in that, i can add a new PCB screen here too) Best Regards, Rio

the problem is solved by adding few capacities at TL072. I'll describe the solution in the cem3378 thread after weekend. Now the filter sounds fine. Greets, Sebastian

If you get no reply after longer delay, let us know.. Best Regards, Rio.

Mike's shop is really ok and sufficient for DIY projects. All my device running fine with his boards ;) and his support is great. The rotary encoder you can get from voti. They are called SW-ROT-1. http://www.voti.nl/shop/catalog.html?SW-ROT-01 You have forgotten the bankstick-board from Mike too! And if you want to buy more than 3 EEPROMs, you can buy these somewhere else (they will be a lot cheaper e.g. at conrad) knobs and datawheel you can get e.g. from ALBS Electronic, but they only accept big orders... maybe you can order somewhere else these things or you canibalize old/damaged electronic devices like mixer etc. ;) Greets, Rio.

Have you noticed the same noises on your installation? I've checked my again. There are 2 noises: the first is net zipper noise. I've solved it mostly by put up new ground lines between the SID+Core+AOUT_LC modules which are in the same case. The second noise is more difficult. Seems the TL072 swings by itselfs and it sounds like a dogpipe, which changes frequency after a while. If I put my fingers in the near of it then the frequency will also be changed. Bad bad...

My device sounds with noises as soon as the filter c.v. is connected to filter. Please, listen to that example in attachment. Did you hear the same with AOUT_LC? Has someone notice same behaviour or can someone say where this noises are come from? Best Regards, Rio example-cem3378-noise-wav.zip example-cem3378-noise-wav.zip

that music in background... :) omg but that oil-beamer ( i don't know before ) looks awesome... Greets, Rio.

Thx for your help, but that sweep and the noise are continuous, when no voltage will be changed. Maybe i'll record it at weekend and upload it here... so you can check it by connecting your AOUT_LC after you've finished your programming stuff. Thx a lot for your help ;) Best Regards, Rio.

i use AOUT_LC. What is the name of your psu? Which outputs are there? Are you using voltage regulators with your psu too? Maybe i'll test that, if i got one. Greets, Rio

i've tested 4 of the cem3378 chips. All sounds in the same way. I can listen to a sweeping noise in background at all... But the chips are connected like in pdf schematic of cem3378. If i press my fingers on the chip...this sweeping noise will be more or less boosted. The second noise is a repeating sound in background, like a train drives on the rails. Third, i can measure a constant high frequency on osciloscope if i switch the psu on. That high frequency modulates the sound waves to thicker ocillations. ..but besides of these facts, the sound of the filter is allright. Only that noises are anoying and not useful for studio recordings etc.. I believe the reason could maybe my psu... i don't know..

Ploytec.de das soll wohl ein Taktgeber sein - Nein, ich suche kein taster. Brauchst Du ein Schweller-Pedal ja ein Schweller-Pedal, kein taster..

And additional i can measure a constant high oscillation on a oscilograph (but i don't hear that)... What could be the reason for that oscillation? @moxi: do you measure something like that too?

@moxi: what is weel? and really no background noise? i've used a +/-15V trafo and used ripple filter + 7805,7905,7812,7912 to get +5V,-5V,+12V,-12V, which i used to feed the filter+AOUT_LC. Damned that i can listen to a sweeping noise in background...i don't know what i do wrong.

ich möchte damit einen CC von einem Synth steuern können (Glidelevel oder Vibro etc.) für den Livebetrieb ;). Das problem ist, dass die kommerziellen Produkte (ganze fusscontroller) meist in einem riesigen Board verbaut sind. Sowas brauch ich gar nicht, das sieht meineserachtens auch ein wenig 'pleite' aus, wenn ich mit so 'nem ding ankomme und ist a) unhandlich und b) brauch ich ja nur das pedal. Naja und bauen... eher in diesem Fall weniger. Da fehlt mir grad ein wenig die zeit und lust.

Hi, vielleicht hat jemand eine Ahnnung ob es sowas gibt, bisher bin ich erfolglos. Ich suche einfach ein Fusspedal mit MIDI-OUT (möglicht kein board sondern nur ein Fusspedal) mit dem man einen CC, Values (oder zumindest einen vordefinierten CC steuern) kann... ich seh immer nur das es Pedale mit 6,3 Klinke gibt. Hat jemand eine IDee? Grüße Rio.

nice moxi.. how does it sound? Have you notice background noises in CEM3378 filter and which Schematic/Plan you use for that or can you show your pcb? Because i'm interessted to reduce that background noise at much as possible in my solution. Greets Rio.

Für CODE:BLOCKS gibts auch eine 1A Anleitung von Stryd_One in der Wiki. Damit hat meine installation 100% funktioniert. ich habe meine compilierten binaries via MiosStudio direkt auf den PIC geladen. Man kommt nachher sowieso nicht drumherum. Beste Grüße Rio.

Ist es möglich zwei Core module (mit PIC18F452) per J11 zu verlinken, um Midisignale von dem einem zum anderen zu versenden? Wird dann ebenfalls auch das Midisignal durch den MIDI OUT-Port des sendenden Cores über den Oktokopler abgesendet oder wird bei der Programmierung J11 explizit über eine spezielle funktion angesprochen? Kann das zu empfangende Core Modul gleichzeitig Midisignale über J11 und MIDI IN über die selben Routinen empfangen? Don't plug the optocoupler (IC2, 6N138) into the socket when using the J11:MI (MIDI-IN) pin as an input, otherwise the Rx input will get the data from two different sources, which is not provided by the MIDI protocol (point-to-point). ...sieht so aus als ob man nicht beides mit einander betreiben darf, richtig? Grüße Rio.

Oh thanks for support (tk+wilba), i never used that menu before... i've to try out it at home. Greets Rio.

You mean velocity isn't mapped as standard to control master volume (i've to define it by myself), right?

Ok, the K#V in Knobs menu shows me the current velocity value which is played. Min, Max is defined between 0 and 255 for that knob and correct shown. So i'm sure that the velocity will recognized, but the signal output plays still in full volume level (incoming velocity parameters don't influence the signal out). Greets Rio.

Totally simple: i use a pattern in MBSEQ V3. If i play a sequence with different volume levels - MBSID2 doesn't take notice about that incoming volume information. If i use another syntheziser instead the MBSIDV2 -> it works... i've only upload your last setup_6851.hex and setup_8580.hex to my MBSIDV2 - nothing more. The same issue happends, when i press a key on my roland keyboard with velocity-sensitive keys - the velocity will not noticed by MBSIDV2. To get sure that the volume level control works correct on MBSIDV2 for the SIDs, i have tried to change the volume level in MBSIDV2 box manually for the current playing patch - that works very well. My hardware is 4x Core_V2 and SID_V2 upgraded platines. Everything else works very well. Did anyone else notice that problem?

I've upload last MBSIDV2 RC17 (setup 8580 and 6581 hex) yesterday and checked out. Volume/Velocity will be ignored again. (i've checked up another synth device, there it works fine). what i've forgotten to setup? What could be wrong? Best Regards, Rio.

convincing. we looking forward for better solutions.