What's happening with my bass drum sounds?

Elektron Gear Analog Keys/Four
#1

I wonder if anybody can help with this.

My bass drum sounds sometimes seem to drift dramatically from being powerful to thin. I can’t figure out why but I’m wondering if it’s something to do with the stability of the filter. I’ve set the oscillator to retrigger with each note so we can rule that out.

I know that all the power from an analogue synth bassdrum sound comes from finding sweet spots for a resonant filter, specifically it’s decay and sustain values etc - and also the pitch bend time of the main ocillator.

So that’s my first suspect - that the filter frequency is drifting slightly, from positive to negative phasing.

Does that sound plausable? If so, can I do anything about it? It’s a used model that I bought a couple of weeks ago and I haven’t calibrated it yet. Should I try that? Are there any risks involved?

Thanks.

Sounds not changing instantly when changing pattern
#2

Is it possible that you have a tiny tiny value set to any of the LFO depths? Even if they read 0 they aren’t actually 0. They need to read (0). You can set them to exactly (0) by holding function and turning the depth knob.

#3

There are no risks in calibrating AFAIK. Recommendation would be to have your A4 powered up and idle for 20-30min, and then proceed in doing the calibration. That way you could pretty much rule out any “error” values geting into the calibrationprocess due to a cold start of your unit.

#4

Do you have OSC Drift on and/or OSC TRG off?

#5

Both of those points ought to be clear(er) in the manual. The manual pretty much dissuades you from home calibrating ! I’ve had to, but it always worried me I was undoing a better ‘factory’ fine calibration …
+
Also @billywood, taking e.g. preset ‘BD 95’ you can see what happens when you interrupt the filter resonance. Put down some BD at 1 5 9 13 and 15, then plock the F2 resonance progressively lower on 15, listen as the drums disappear ! You may be experiencing a subtler version of this too !?

#6

Thank you very much, everyone.

@Paland: I was doing my best to be sure that it was set to zero. I even changed the LFO destination to something unrelated. I didn’t know about the (0) tip, so that’s handy!

@miketheman: Thanks for the advice on calibrating. I was dissuaded by the manual, but couldn’t think of any real risks. Cailbration has always been a necessary part of voltage controlled synthesis, right?

@djd_oz: OSC TRG is definitely on. I must admit that I forgot to check OSC Drift. I’ll feel pretty silly if it’s on!

@avantronica: I think I know what you mean. Similarly, when I add a snare into a bass drum pattern using a soundloc, it destroys the resonance of the bass drums. What’s that about?! Is there a way around it or do I need to reserve a full track for bass drum sounds?

#7

there’s a couple of older threads on this topic both here and elektron-users i suspect, but i think the gist is that a purely filter res based sound needs some time to get excited, adding a bit of noise in may accelerate, best check out the earlier advice - it’s not a fault, it’s just the nature of the analog beast

#8

Interesting that the “BD95” preset uses only the second filter. My BD sound was using a combination of both. I wonder if the first filter is more needy in terms of the harmonics it needs to excite it into self-oscillation?

Back to my first bass drum… as it happens, I did have OSC drift on but switching it off didn’t change things. I just scrapped my sound and used BD95 as a starting point to get to the more click-boom sound I was after.

#9

If your pattern has space try putting a trigless lock before the kick drum. I believe this has the effect of getting the voice ‘ready’ a bit.