Sq1 callibrating on 1 volt output

Leoschoutrop · Post by **Leoschoutrop** » Sat Mar 16, 2019 9:50 am

I have a sq 1 but getting my oscillators tracking right isn't that easy
Partial due to the small knobs but another thing is annoying more:
When put on 1 volt output it only delivers max 0.98 volt , when on two volt output it max delivers 1.96 volt etc
Is there
Any way to callibrate it so that 1 volt means 1 volt ??

voip · Post by **voip** » Sat Mar 16, 2019 11:23 am

How accurate is the measurement system? Even good quality Fluke multimeters are only specified to give 2% +/-3 counts accuracy on the voltage ranges, so 2.000000 volts, produced by a known e.g. recently calibrated to NIST source, might read anywhere between 1.93 and 2.07V. A cheap (e.g. Tenma) multimeter spec is given as a "Best Accuracy" figure that is better than this, but "Best Accuracy" is a rather vague term, that wouldn't stand up to professional scrutiny. So the message is basically, verify the measurement system before diving in and making adjustments.

Leoschoutrop · Post by **Leoschoutrop** » Sat Mar 16, 2019 1:12 pm

Good tip
Thanks
It's not only the multimeter, it's also thT the tuning acts accordingly. No right tracking When 5 octaves you 'll get b instead of c, with 2 volts , same proprtional deviation
( peterson strobe tuner )
Therefore the question on calibrating the a and b. Cv Outputs

OpAmp · Post by **OpAmp** » Sat Mar 16, 2019 9:35 pm

Hi,

AFAIK, there is no easy/obvious way to calibrate the CV output voltages.

Bye

voip · Post by **voip** » Sat Mar 16, 2019 10:55 pm

The joys of analogue ;-)

The voltage steps between semitones, when using 2V to cover 5 octaves in V/octave mode, is 33.3mV, placing the voltage for top B at 1.9667V so, putting a lot of faith in the voltmeter readings, the SQ-1 maximum output might well be above this level. Could it be that the target synth CV input is also slightly less sensitive, so the combined effect is slightly flat? Is the resolution of the SQ-1's potentiometers sufficient to allow easy adjustment to 1 semitone across 5 octaves, anyway?

Does the target synth have a pitch control that could be used to correct for the tiny offset?

Are the batteries used in the SQ-1 fresh? The user manual quotes around 5 hours use.

nayam · Post by **nayam** » Mon Aug 26, 2019 8:02 am

Very useful thread, thanks for information.

Leoschoutrop · Post by **Leoschoutrop** » Mon Aug 26, 2019 12:48 pm

To all questions:
No
The battery and targetsynths are oke
Problem is simply thet the sq1 is not callibrated on 1volt/oct and no adjustment possible
With hz/ volt synths ( ms20+ ms50 here) it seems to work better/ more tight in tuning and whole range of the pots can be used more handy