ModBap Osiris question on Sub OSC output - Weird things happening

Hi all,

Second post here.

Just a question as stated above. I have contacted ModBap weeks ago but no answer from them. Maybe someone knows.

Here it is: while using the 2 separate outputs on the Osiris, (one for the voice and the other for the sub OSC), I get a non stop sub out even when stopping my sequencer. Output is connected to a separate input on my mixer (4ms Listen4). I do understand that the sub out gives a full volume, which is not a problem as I can tame it down with the mixer.

The weird thing is that when I hit stop on my sequencer, the sub out keeps delivering its full volume out. It will only stop on a double press on stop on the sequencer. MORE: when double pressing stop on the sequencer, I still get a signal (audio?) coming on my mixer (4ms Listen4). I do not hear anything but it looks like something is still coming out. Confirmed by the fact that I get the same visual signal on the A/B inputs on my Octatrack. Same as the 4ms mixer.

Any idea?

Thanks for any hint in advance, much appreciated as ever,
Olivier

Hi,
Sounds like a normal behaviour for me.
The sub out of the Osiris acts like a classic VCO and not like a synth voice : it's playing the sound continuously and is not affected by the decay knob.

You have to pass it thru an enveloppe + VCA combo.

Cheers,
Cédric

Hi Cédric,

Thanks a lot for your help. I was expecting it to be this.

When you say "You have to pass it thru an enveloppe + VCA combo", could you detail the actual connection?
Should I just output the sub OUT to an EG (I have a pip slope mk2 at the moment) through its gate or trigger?
And then to the VCA?

Thank you very much for the help, much appreciated.

Had a glance at your 416 rack and there is a lot of the same I am looking at (Voltage Block for instance).

Best,
Olivier

You're welcome !

The exact connection would be :
Sub out > VCA signal in
EG out > VCA CV in
VCA signal out > mixer

(You Can also find EG with integrated VCAS, like WMD Javelin, Cosmotronic Delta V, or the latest 4ms that looks dope !!)

You'll also need a trigger or a gate to start the enveloppe.

The role of the function generator here is to modulate the amplification of the audio signal going into the VCA.
Imagine a volume curve if you like.
Once the enveloppe is not triggered (sequencer stopped) your volume will stay to zero.
It's also interresting to put a low pass filter (vcf) between VCA and mixer.
Then you can modulate the filter with the same enveloppe (with a multiple) to give more dynamics to your bass sound ! :)

Hope it's clear, it's one of the tricks, but some folks here could give you many others.
I'm not a modular expert :)

I highly recommand voltage block ! ^^
Mimetic Digitalis is a very good option too, in reduced spaces.

Best,
Cédric

Thank you very much Cédric,

Very kind of you to have taken the time to detail all this.

I am actually using a Mimetic Digitalis (with Lapsus OS) and really like it.
Hoping for a Voltage Block to restock as it is impossible to find one.
Really appreciate all the tips as I am only starting with modular.
Having a blast :)

Best,
Olivier