I wouldn’t try using that cheap multimeter for this if you want that level of accuracy!
You can spend a lot more cash than this getting stuff that’s more accurate!
Thinking left field a bit, would you not be better off with a tuner? Even an iPhone app might provide a more accurate reading than your multimeter - that sounds ridiculous but they are pretty good, this one has accuracy ±0.01 semitone (±1 cent)
its not really tuning though, it’s about voltages. but yeah maybe it is too blunt an instrument.
It was recommended on muffs for calibrating the rubicon by the guy who designed it, maybe i just got a duff one.
I have a similar cheap multimeter and they are fine for checking things like resistor values or that there is about -12v on the -12v rail etc… but impossible to say, match resistors with them! They’re just not very good!
if it was about by exactly .6% that would be just outside the tolerance of the device but almost pretty much account for the error, I’m seeing.
On the plus side assuming that the multimeter is at fault then i now have a new more reliable voltage source and meter in the er101 for recalibrating my osc and other voltage sources.
Ok used the 102’s voltage measuring to get as near as perfect voltages from My Analog Keys (using its internal trimmers). So C0 = 0v, C1 = 1v etc…
Then used these to re-calibrate all my oscillators and everything sounds great with 101 except for the very first voltage of 0v, which has a small positive bias of 0.010v (according to the 102).
Is it possible to tweak this down any further (closer to 0) at all, could it be OS tweak somehow?
From my 101 feeding back to the 102 to measure voltages they go like this: 101Out ----- 102Reading
0.000----------0.010
1.000----------1.001
2.000----------2.002
3.000----------3.002
4.000----------4.002
5.000----------3.001
and so on.
Its just the first one (or 0v) that seems to have that little bias. Its nothing major, so no worries if not but just wondered if there was a way to tweak it?
I’m getting really lovely tracking from my osc now apart from that very first note/index.
So I just tried this method to tune an OSC303 I’ve just built for someone and I couldn’t get it to stabilise, it was like the voltage reading was following the saw wave i.e. it was flickering about all over the place.
Am I misunderstanding something? Feel a bit dumb all of a sudden!
Well, not that dumb, I tuned the OSC303 up anyway using an iPhone app called Tunable - it’s very good - sounds as perfectly in tune as this gnarly oscillator is going to anyway, there is some drift which is to be expected but it hits the green across three octaves, so more than good enough and expected behaviour.
Haha - thanks yep slight misunderstanding there - I was being dumb
I realised my mistake after I posted, but thought I’d wait for an answer anyway…
Onward and upward!!
Is there any possibility of an update to make it to work as a tuner? Although having said that, it would probable make more sense to put this in the ER-301?
Unfortunately, there is no fix for this. The ER-101 cannot output exactly 0V. Due to the limitations of the DAC it will float slightly above. All other values should be good though. In practice it shouldn’t really be a problem if you use 1V (or higher) as the root.
Thanks for the quick response! Do you mean tuning/calibrating my oscillators so that 1V is my root pitch and then using (in the 12ET voltage table for example) only index 12+ (or shifting the stored voltages up 1V)? If I’m understanding correctly, I’ll try that when I get a chance.
P.S. On a totally unrelated note, I’m off to Japan for the first time in a few hours! I’ll be in Tokyo for the next week if you’re anywhere near there and want to let me buy you a beer in return for the awesome modules, or if you have any interesting recommendations.