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[rotallicso]

Just curious if the wayward voltages either side of the nominal 5V are in any way pertinent to my excessive VCA thump issue, plus i'm also curious about whether the unit I have has been calibrated or could be calibrated better.
Put it this way, there's a substantial difference in the bipolar range of my wheel which is annoying (i'd expect subtle variations, but this is quite large)

Any help appreciated - it's a qualitative comparison - feel free to supply voltages if that's simpler for you

.....TEST





This looks more fiddly than it really is

The important aspect is just that i can hear the pitch differences from the nominal ‘5 volt’ control signals

The one we set up as a reference is the wheel forward
We do this by attenuating the ‘5 v’ to provide a 2 octave bend forwards using the T.Ext on Pitch
This is then compared to the nominally identical magnitude signals from ‘wheel back’ ‘gate’ ‘EG2rev’ ‘EG1rev' & ‘SqrLFO’
This is achieved by tricking the VCA open, calibrating the T.Ext and then running through the test - it mainly involves re-plugging one cable in 4 more outlets
To make it audible and easy to measure, it’s a highish start pitch and each phase needs to be held for a 3 or 4 count to enable me to compare/measure

Sounds fiddly, but it’s done in max 5 minutes in total, but please let the machine warm up for 10>15 first

Three images and a reference mp3 recording which also includes an irrelevant snippet of the calibration of the T.Ext dial before the test begins
But I left it in because it highlights just how obtrusive the key thump is, EG2 release and other parameters are same as previous test

The gain staging presented ought to be about right for a tap out the headphone out into a recording device (the signal out jack is used to hold open the VCA)

This results in a 3 semitone error on my machine (the wheel should be +/- 5 it’s +4,7ish to -5.3ish and other values are equally astray (either side) of the nominal 5 - it may point to a badly calibrated unit which in turn may explain why the VCA thump is substantially louder on my Unit than on the one i’ve heard tested by the retailer

Cheers



audio example - note thumps whilst fine-tuning up T.Ext level and variation from outlet to outlet
http://picosong.com/6Zbi/

the deviation from nominal 5 is not a concern in itself - it's the relative differences i'm concerned about - especially wheel appx 4.7 > -5.3
....................


Again ANY help appreciated - it's a simple little test or if you have a voltmeter it's a trivial one - but i am ESPECIALLY interested to connect your Thump experience with these calibration stats

Thanks in advance











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