When is the next OS revision coming out?


The title says it all. I know this has been talked about as though it were imminent for some time but just wanted to get an idea where things are at at this point.


Further to your question, does anybody know te last os version that had consistent voice volumes? I want to start using my parva in a live setup.


I’m sorry for not responding to this (and a couple of other posts) more quickly – I somehow unsubscribed from email updates. I’m releasing a new OS rev today. It fixes the multi-octave interval weirdness, a PWM bug, and a couple of other small things.


It appears to have been broken in 51, so in theory anything before that didn’t have the issue.

That being said, the tuning stability and other improvements in 51 and beyond might be more valuable to have in a live setting.


I intended to release this version yesterday evening, but in my last minute double-check I found that there was a new bug in the PWM code. I’ll try to get it fixed this morning.


Any progress with those fixes Brad?


Just pinging you again to see how things are going


I ordered mine about 5 weeks ago. It was originally going to arrive on Tuesday, but because Mr. Ferguson had to install new firmware into my Parva, it should come this Friday. This means that the latest firmware will come very soon


I think I’ve fixed the oscillator amplitude bug without introducing any new bugs. This version also fixes PWM modulation (was slew-rate limited in previous version) and several things related to VCA Level modulation.

voicecardv64.zip (82.4 KB)

My voicboards are totally out of tune! (now: HOW TO TUNE YOUR PARVA)

Hey, that´s cool. Busy at home right now, so will need some time to check it out. Is this one addressing the “Inconsistent voicecard response/tone” issue as discussed here: Inconsistent voicecard response/tone
Thanks a lot!


Brad is this the only update file we will need or is there going to be an OS update that will be forthcoming also that needs to be installed?


Yes, I think I got it this time. The issue was created as part of a rewriting of the DCO control code that improved tuning consistency and amplitude consistency, and reduced aliasing significantly, so fixing it without breaking anything else was a little difficult.

There will be a mainboard firmware update, but the fixes in the voicecard firmware don’t require it.


Here’s some initial feedback.
First - it is a lot better. Update was no problem, all voice cards at 0.64 (main board at 0.61).

My goal was to take an init patch (all VCOs off, VCA envelope at 0,0,127,0, VCF fully open, clean OSC ON, slop 0, detune 0) and start from there.

I will concede there may be user error, but creating that patch and then attempting to save it was a mess. I still don’t know why I can’t save and recall something reliably. It comes back either not saved at all, or partially changed. Again - I concede it could be user error, especially since I wasn’t looking at the manual and there’s no confirmation when you save or load. It also could be I have a different patch auto-loading on boot (forgot to check that).

Anyway, back to the testing. If all DCOs are at 0 and the Volume pot is turned up and you press a bunch of keys, you hear a high pitched whine very clearly. Less noticeable with only 1 or 2 pressed, but adding keys really makes it obvious.

With any oscillator or noise turned up, you can’t really pick it out.

I will state, but not swear to it, that initially I thought all voice volumes were consistent, but after running through the DCO and VCF calibration I do hear some variation between voices, but it is way way better than before but still noticeable.

Again - not sure of the interaction between the newer voice board OS and the older main board, so doing any of the above could have overwritten/negatively impacted the voices.

My summary though it that the volume between voices is more consistent, the overall levels on the Parva are easier to control to get a good output gain, and the tuning is still stable. The filter resonance still comes on strong between 105 and 120, but either I’ve been away from it for a long time or it’s been changed a bit, but the filter in general sounds nicer inmost of the modes than before (yes, very subjective comment). Don’t know what else I was supposed to test since I didn’t see a list.


So, anyone else going to confirm or deny what I’ve heard? I’m sure Brad would like more data points if possible


The main purpose of this revision was to fix an issue with the oscillator amplitude not changing correctly when changing notes. With a single oscillator set to sawtooth, play a low C eight times; now all voices are playing low C (silently). Play a high C – does the note sound at the appropriate volume?

I’m not sure what’s going on with your patch saving/loading. It seems to work fine for me.

The changes to the filters were made in the v0.60 release.


Ok, thanks.

Suggestion – when you save a patch, could you maybe pulse the name in the saved location a few times? That would give visual confirmation that the save process was successful without the need for extra dialogs.


That’s a great idea!


I also think I discovered my patch save/change issues. Do you respond to any program change messages received? If so, can we get a user setting to disable that?


Is the power supply switchmode? Switchmode power supplies are notorious for inducing high pitched noise. Most wall-warts are switchmode these days - easy to tell, light and input voltage will be listed as 100-240V…


Yes, it’s a switching power supply, but it’s pretty quiet. There’s a lot of other digital circuitry (eg those pesky OLEDs) that leaks a little noise into the signal path. I personally consider noise that’s only audible when all of the oscillators are disabled and the VCA is wide open to be acceptable.