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WIGGLING 'LITE' IN GUEST MODE

Useful tuning post
MUFF WIGGLER Forum Index -> 5U Format Modules  
Author Useful tuning post
megaohm
This is from the euro subforum but applies to greater and lesser extents to all analog VCOs. Make sure you read it before your next tune up.

https://www.muffwiggler.com/forum/viewtopic.php?t=187467
DrReverendSeance
Thanks megaohm! thumbs up

I think this article is also in the general modular forum.
leeski
applause
sduck
I moved that thread to the euro forum after being disappointed that he only covered 2 euro VCOs. It would have been an interesting post if he had included even a few more VCOs. I would have loved to see how the MOTM 300 or the Q106 fared in this.
daveholiday
I thought this was a pretty cool experiment. I might consider doing this with my 4 Q106 just for shits and giggles....might be a cool thing to do on a Sunday afternoon! I'll post results if I decide to try this!


"It's all shits and giggles, until somebody giggles and shits!"
noddyspuncture
megaohm wrote:
This is from the euro subforum but applies to greater and lesser extents to all analog VCOs. Make sure you read it before your next tune up.

https://www.muffwiggler.com/forum/viewtopic.php?t=187467


.... my VCO's are R.A.Moog 901's... they will never "settle" - always 'on the move'... wink
daveholiday
So I let my guys off work early for the eclipse so I decided to do some oscillator testing. My test was a bit different but still much the same. I didn't choose to pre-tune, I just set knobs the "same" on all four oscillators before power up and recorded the results. So essentially the test was just to see the variation of the oscillators for 50 minutes after startup. The results are posted below.

In a nut shell, it looks like I need to turn the system on 30-40 minutes before tuning....but we all already knew that going in to it!!

DrReverendSeance
Thanks! What Oscillators were you using?

I notice that the Euro test had 3-4 hz difference from start to finish, whereas your test the difference between min and max are within 0.2 hz of each other.
coyoteous
I used to play out locally and regionally, mostly as/with(?) a duo... between the two of us we had at least 50 VCOs (sometimes as many as 100 with borrowed gear, and counting polys with and without auto tuning):

Emu and Moog modulars (921s); Oberheim EVS, OB-8, OB-X, more SEMs, Xpanders; Prophet V, Mini Moog and usually 3 or 4 Arp 2600s, etc.

If we were in a fairly constant temp environment with the gear out of any direct sunlight (played outside almost half the time... changing wind cooling can be a killer, too)... thirty minutes proved to be all that was needed for all the gear.

We either had to tune quite a bit, because of the environment changing, or hardly any at all after warm up... even the self-tuning stuff (I had a habit of hitting tune too soon that I broke, and after waiting, often there was no notable difference).

Anyway, still my habit to wait half an hour, and it still works fine... I will do this testing sometime though, just to know.
daveholiday
DrReverendSeance wrote:
Thanks! What Oscillators were you using?

I notice that the Euro test had 3-4 hz difference from start to finish, whereas your test the difference between min and max are within 0.2 hz of each other.


Sorry I should have given more data!!

4 Dotcom Q106 oscillators with CRS installed.

Also I was running at the 8' octave range witch was around the 126 Hz range, Hence, the lower range between frequencies. One trend that I did notice when graphing out the results was that 3 of the oscillators dropped immediately then started climbing back from the initial start up frequency. The fourth (OSC 3) just hovered around the same frequency then rose a bit toward the end.

I can past a pic of the graphs if anyone is interested.
DrReverendSeance
daveholiday wrote:
DrReverendSeance wrote:


I notice that the Euro test had 3-4 hz difference from start to finish, whereas your test the difference between min and max are within 0.2 hz of each other.


Also I was running at the 8' octave range witch was around the 126 Hz range, Hence, the lower range between frequencies.


Yes, your right. The Euro test was at 426 hz or so it makes sense the larger gap. d'oh!
hsosdrum
Between 1974 and 1977 our keyboard player used a MiniMoog which, along with all our other gear, was kept in the equipment truck 24/7 except when we were playing a gig (250 - 300 nights a year). We played all through the upper midwest of the USA (from Colorado through to Chicago and everywhere inbetween), where temps often dropped way below 0 degrees (F) during the winter (sometimes below -20 degrees (F).

When the equipment truck arrived at the venue (usually around 6 hours before show-time) the very first thing the roadies had to do was get the MiniMoog out of the truck, bring it into the venue, plug it into an AC outlet, turn it on and let it warm up for at least 3 hours. That's the only way we could guarantee that it would be in tune in time for the beginning of the gig. Just to be sure the warm-up got done we required that they perform this ritual regardless of how warm or cold the weather was. One time during the winter they forgot and the synth wasn't usable until during our 3rd set, about 3 hours into the gig.

Although you can re-tune guitars and basses to match an out-of-tune synth, you can't re-tune a Hammond organ or a Fender Rhodes to match it.

P.S. You want tuning nightmares? Try touring with a 1972-vintage Mellotron 400. Even in 1972 when it was brand-new it was still shall we say, "an adventure".
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