Elektron-Users

Sofine wrote:
Fuseball wrote:
On the CV Setup page there should be 3 values you can set.

Type (Pitch V/Oct for the SH-101)
Middle C (Sounds like you already have this value set correctly)
V/Oct (This is the one you set to get the scaling between octaves correct)

I had to tweak the V/Oct value to get my Moog Little Phatty playing nicely with the A4. I assume this the same as the Scale feature of the Kenton converter.

Speaking of CV pitch to the Little Phatty, what setting are you using for V/Oct? IIRC I'm using 0.97 and also 3 for middle C.

I read somewhere that the Little Phatty should track at 0.97V.

Mine comes out at 1.04 V/Oct. I set Middle C at +0.02 V. I figured that as the Little Phatty goes from -5V to +5V then I should try and get it as central as possible. Sounds about right at that setting anyway.

I think the Moog treats the Pitch CV as an offset from the last voltage generated by a keypress. I have to hit a C (C3 in my case) which maps to Note C5 on the A4 (lower C of octave 0). I managed to get the tuning of the Little Phatty wildly out at one point but I think that might have been because I stopped the A4 mid-sequence.

Also, turn Auto-Tune off.

Ok here are my A4 CV readings for CV A set to v/oct middle C as 3v
C2 -0.006v, C3 1.036v, C4 2.078v, C5 3.112v, C6 4.153v, C7 5.188v, C8 6.229v, C9 7.28v, C10 8.32 v

I also tested my Oplab:

C2 0.043v, C3 0.984v, C4 1.990v, C5 2.995v, C6 4.001v, C7 5.007v, C8 6.013v, C9 7.03v C10 8.04v

And my Kenton Pro2000MkII

C2 0.004, C3 0.997, C4 1.997 C5 2.997, C6 3.997, C7 4.997, C8 5.997, C9 6.997, C10 8.01

For the test I used a Fluke 110 True RMS Multimeter (so a very accurate one, not a cheapo)

I was surprised that the Oplab did better than the A4, it could be that the DAC in the A4 is not as high resolution or it could be a bug in the A4 OS.

BTW It wold be handy if someone else with a decent multimeter would post their results so that at least there are a few results to look at.

My multimeter is at my parent's house (I'm fixing up a pinball machine there). When I get it back I will measure my A4's CV output voltages for you. I'm interested to see how it relates to the Little Phatty's tuning.

darenager wrote:
BTW It wold be handy if someone else with a decent multimeter would post their results so that at least there are a few results to look at.

CVA tip V/oct, middle C = +3V, V/oct = 1V, Transpose = 0

Fluke 111 used (which is exactly 1 better than yours Daren, so there ) Warmup ~15 minutes.

A4 keyboard and octave controls used, notes outside this range were tested by adjusting the TUN parameter to +12 and +24

0.008
1.043
2.084
3.125 middle C
4.172
5.211
6.259
7.31
8.36

Side note: I can't get middle C to be exactly 3V without adjusting the "middle C" parameter in the setup menu.

With middle C = +3V I get:
TUN = -2 and FIN = +63 gives 2.974V
TUN = -1 and FIN = -63 gives 3.018V

With middle C parameter set to 2.88V, TUN = 0, FIN = 0 (measured Voltage = 3.001V @ middle C) here are the results:

-0.115
0.921
1.961
3.001 middle C
4.048
5.088
6.135
7.19
8.23

So it looks like I have in the neighborhood of 0.04V/oct tracking error near middle C when calibrated.

Ok so duh it just struck me that my V/oct error could also be adjusted with the V/oct parameter

Same test with middle C = +2.88V and V/oct = 0.96V

0.012
1.007
2.005
3.003 middle C (drifted 0.002v between tests)
4.007
5.005
6.012
7.02
8.03

Morals of the story:

1) A4 CV out works fine, it just needs to be calibrated to real world values if you require accuracy.

2) If you're using Voltages to control things, it's nice to have a good Voltage measurment device.

Hmm, it would be nice if the values set were reflected in the actual values output - judging by your results it should be possible for Elektron to at least get them within about 0.005v of the displayed values.

Thanks for posting!

It would be cool if the numbers were accurate. I wonder if it might not be possible due to temperature variations. There would have to be some feedback between the output voltages and the OS to have a tuning and scaling routine. You and I have similar scaling error though, so who knows.

Thanks guys, all this info has been really helpful. I've adjusted the settings as advised and am happy with the results. Cheers!

pocketsimon wrote:
Thanks guys, all this info has been really helpful. I've adjusted the settings as advised and am happy with the results. Cheers!

Yes, thanks guys. Will try these adjusted settings with phatty and SEM this evening.