OB-6 uneven filter amount

OB-6 uneven filter amount
« on: November 29, 2018, 06:27:51 AM »
Hi all,

I have an OB-6 which I absolutely love, but last night while making a patch I noticed some behaviour which was somewhat hindering my patch making and sound I was trying to get.

On my unit there are 2 or 3 voices in which the filter envelope amount seems to be ever so slightly higher than on the rest of the voices. The best way I can describe it is that it sounds like the envelopes on these 2 or 3 voices are being hit at a slightly higher velocity, even though I have velocity turned off. It's always the same 2 or 3 voices in sequence, and it's most noticeable the more resonance is applied, and the lower the filter cutoff is set to. When there is no resonance applied, or when the filter cutoff is mild, it isn't really audible. I haven't really noticed it on any of the factory presets.

Most of the time I find it occurring on 3 voices (4, 5, 6), but sometimes I find it occurring on just 2 (5, 6), and at one point it only happened on voice 5 (I think, not 100% sure how to identify the specific voice). That said, a few minutes later it was happening on the three voices again.

What I want to know is if this is considered normal behaviour? This is my first analog poly, so I'm just trying to figure out what's normal and what isn't. It's something I think I could live with most of the time, but for this particular patch I was working on, it was forcing me to constantly adjust the envelope amount ever so slightly to try and balance the perceived velocity of chords. Quite annoying...

I have an audio recording of this issue occurring on voices 4, 5, and 6 (most audible on the final patch). Velocity off, no LFO things going on, happens on all VCO's individually and together, no effects or X-mod. Calibrating doesn't help. Doesn't go away entirely as the machine warms up (at the point of this recording it had been running for over and hour).

Thanks in advance!
« Last Edit: November 29, 2018, 06:29:23 AM by usrockband »