jrp

anyone using all their gates at J5?

i cannot recomend this. Linear regulators will be very unhappy in such a case. It is not that the regeulator can adapt in a mannor: "Ok, i need to drop 3V, so i just adjust myself to 8.5V." The Voltage will drop, yes, and the regulator will be fighting and sweating, not being able to do what it´s supposed to do: Stabilize voltage and get rid of any ripple. It will lead to hum and possible failure. For non demanding circuits (not this one!) it would then be better to go without a regulator altogether. Don´t try this with your sid though. Also, to be safe it is common practice to account for 10% mains variations. If you measure voltage and the regulator is a little of, just check the voltage at it´s input. These Parts have tolerances, so you might be getting 8.7V from 12v. That would be fine.

Any news on this? I also noticed that with some patches it can happen that the AOUT or triggers aren´t working as expected. Sume other functions as well, seems rather strange and hard to repeat. I have another thread about this, but i just saw yours. Propably it has to do with new assignments in the setup file in conjunction with older patches. Problem is i always noticed this late, so i cannot say what changes exactly made this happen. In my case Trigger 1 and 8 are not working on my slave core, on my master core i had the same problem with triggers falling back to 0. Maybe someone else besides TK can check on this or confirm it is working for them... Someone with a MB_SID using all triggers, or with an "exposed" core module so they don´t need to take stuff appart. Then at least we know it´s not a bug (what i actually doubt) but some mistake at our side (although i carefully inspected solder joints a thousand times). Thank you!

Old thread but i just saw this. Beautiful work and idea! I bet the kids love this. I work at a school also, got to show this to my boss! Is it running ableton live?

Setting up a DOut shift register works for the master core, but unfortunately not on the slave module. Is this even supported? I used SR#1 for this. The three data lines coming from the pic are all low. So maybe J5 is the only way for slave cores to axcess external switches?

even stranger: on my master core Trigger 1 is high, activating the trigger on the cs flips it low for half a second. Trigger 2, 3, 4, 6 are acting the oppostite way. When turned on they fall back to low after half a second. Trigger 5, 7, 8 are functioning normal. Again, all trigger assignments in the setup.hex are turned off, J5_Function = 3

i did a fresh install using the unmodded version downloaded from ucapps. All flags controlling external triggers were set to 0, #define DEFAULT_J5_FUNCTION 3 #define AOUT_INTERFACE_TYPE 3 #define DEFAULT_EXT_SWITCH_DOUT 0 I also disabled all shiftregister pins except for my exec button to clone this firmware to my slave core. I then reinstalled my own version setup for my hardware to the master core. It doesn´t change a thing unfortunately. Ext trig 1 is always high, 8 is always low, 2-7 are working fine. Is this a bug? Can someone confirm this is working? Propably i´ll solder in a single dout register to my slave module and try to use that one.

I use both and think they are both great. With the 6581 (and actually the 8580 as well) an external VCA is very very nice. That way you have no more bleedthrough and you can controll the volume with the high resolution software envelope (and modmatrix). Works and sounds perfect. Oh, i like the 6581 Filter!!! But true, it is not as effective as the 8580. But it has a very nice character. My advice: Use both! Somewhere in the manual or the documentation there is an audio example comparing the two chips. Sorry, can´t find it right now.

Hello, I wonder if anyone else has encountered strange behavior on their MB_SIDs. I belive this has to do with firmware updates as whenever something like this happenes it affects older patches. When starting with the init patch erverything seems to be working (exept for my trigger-outs 1 and 8). Symptoms: (these are all on my Core #2, Master Core seems to be working flawless) One Sid being out of tune - you have to transpose it to +50 to get into the range that should be +0. Happened only once so far. Can be solved by switching patch. One CV-Channel not working or ommiting the first half of it´s range (from 0 to 800 it outputs 0V, then output raises to 2.5v) Only CV7 is affected. Nothing is assigned in the matrix. This problem disappears when a new patch is selected. External Trigger 1 is always on, trigger 8 is always off. Nothing assigned in the setup asm, other triggers working fine. I am using J5. The external trigger 1 never worked (found no soldering issue), trigger 8 just recently stopped working. I really hope to fix this. I was doing a lot of uploads, mainly changing buttons, etc. The firmware i am using has some new buttons and encoders added, i cannot imagine that this is causing this behavior, but on the ther hand, if no one ever experiences stuff like this....

Did you really experiance audible distortion when AC coupling the signal? Should be very doable with a low enough Lowcut around 5Hz. Eg 330nf into a 100k load. Using a sineshaper is in fact nice as you can morph from tri to sine to square, or from saw to rounded saw to pulse. I found this sounds even more useful compared to the tri to saw fading as it provides a nice range of morphing overtones, really altering the spectrum (compared to just fading in the upper overtones with a tri to saw fade. Of course the fading from tri to saw is nice as well! What would be cool: real morphing of the up and down portion of the ramps at a given frequency. Seems like this is rather a complex task in an analog circuit though... Some digital synths do it, sounds very nice.

Very interesting project! Seems like you have already come a long way. I was only briefly reading across the post on the other forum. Are you blending from saw to tri, or are you actually altering the slope of the signal (like pwm for triange: "very fast ramp up, slow ramp down" to "medium ramp up and down" to " slow ramp up, very fast ramp down)? I couldn´t really make that out on the scope shots. My circuit unfortunately only acts as a blend from one wave to the other, doesn´t sound as cool, but still very nice. Quite some time ago i built a similar waveshaper and i would like to share some of the findings i had. If i understand correctly you are having trouble with volume compensation (?) while morphing through the waveshapes. What i did: - Use the saw to tri converter of a common VCO design (ray willson) and put it under voltage controll. (The trimmer in these circuits alrady acts as a variable voltage source to blend from saw to tri, so it´s quite simple). Signal was simply ac coupled afterwards if i remember correctly, maybe i also used the very same cv to provide an variable offset, balancing the signal around 0v. - Used the sineshaper of the same design, but with a vca before it. This allows to blend form tri to square with a second CV. The first CV will then act as a PWM controll. - I compensated the volume changes using a simple optical limiter circuit in feedback configuration. Instant attack, release tuned for minimum distortion at low frequ. I think i went through the trouble of precission full wave rectifying the signal first, then integrating and controlling the brightness of an LED. LDR is in the feedback of the output driver. Nowadays i would propably use a vca instead, but on the other hand, the optical cell worked very well. It´s a lot of trimmers though... but it holds the signal at 10vpp very nicely Sorry i never did any schematics....

that wasn´t what i meant. It´s just a thought (and slightly off topic anyhow): If one wants ledrings this might be possible with MB_NG or a c written Mios32 app that: controlls the whole list of parameters - organiced the way you design it acts as a patch manager - patches are no longer stored on the sid-core8. shows parameters anyway you want it. It´s not a Sid V3 but a "MB_Sid programmer", realiced with mios32 as a frontend; talking sysex to the Mios8 core running the engine. I have no clue really, but i think the logic that applies when designing a cs can even be managed by a C beginner...

this subject interests me as well. While i am still buissy building my hardware and am using a cs prototype untill now, the remote options via sysex are an interesting alternative for those who wish to adapt the synth-engine to personal workflow. I am pretty sure i will stick to the options the SID application provides, but i also see MB_NG as really powerful alternative. Optical feedback, other LCD options would be phantastic in terms of "bling". After all the reading i did, i am wondering if it might be straight forward to have the MB_NG handle the CS encoders AND patch management - so that parameter values are available for display. As, i said, i am happy with the synth, very happy so i´ll just build it. But still, MB_NG seems so powerful this topic sounds very interesting. Sid with LED rings....

should be pin 9 if you are using an AOut NG. Mybroken channel sits at a voltage a little bit above 0v no matter what i send to that output. If it´s the same for you you should check if there is a short somewhere around that pin, JP2 or IC4. Removing any jumpers on JP2 would be my first action. Around JP2 it is also possible to connect CH8 to one of the other output circuits (CH1-7) to check if it´s working then.

Is the DAC outputting your CV (measured directly at the DAC-chip)? If not the chip might be bad (had this once - one ch not working). If the DAC measures finde the problem is somewhere around the opamp buffers or trimmers.