question: does the MB have background tuning?

[digidisiggi]

i'm just asking this because every day in my studio i switch the MB on and the synth is out of tune (e.g. preset A15, the lower sound is about 1-2 semitone higher then the upper sound). The temperature of my studio is 24/7 stable an about 20 degree celsius.

So i have to use the autotune shortcut many times. After about 5min the MB is finally getting in tune. Is it just mine?

I have many analog synth (A6, Matrix12, Moog's etc.) but no such problems with tuning the synth.

Sometimes after autotuning the Brute, the presets sound totally different. So i have to switch off and on the synth again.

Any idea what i can do? How can i check if the MB is not ok?

best, Siggi

[artElect]

It's the same here with mine...

[F5D]

I will report later this week, when I get mine, but have you tried to let the synth stabilize for about 15-30 min before running any autotune? My Andromeda always requires about 15 min before it is playable and in tune, until then it is really badly out of tune. The good thing about the MatrixBrute is that it is monophonic, so the tuning should be less of an issue than with polyphonic synths. Do the oscillators end up stabilizing to different frequencies at different startups from cold, even when letting the synth to stabilize to normal operating temperature?

Nevertheless, I am also interested in what kind of temperature compensation the MatrixBrute has, or does not have.

[BobTheDog]

Mine seems pretty stable even from cold, I haven't felt the need to run run the autotune yet.

[F5D]

Ok, that sounds good. One point I did not mention in my previous post is that I would never run the autotune of a synth before the synth has reached normal operating temperature, i.e. before 15-30 min since power on. Doing so right after startup could definitely result in an out of tune synth when the oscillators reach normal operating temperature. I once ran the autotune of my Andromeda very soon after startup and as a result lost one of the voices and it required the full long factory tune to get it back. Since then, I never ran the autotune ever again. Of course, a different synth, but still. Back then, I was not used to analog VCO synths. In any case, I wish the two synths reported above will just need a good warmup period + autotune. Even then, I would expect some drift and variance in sounds. That is part of the VCO magic. Let us know...

[Aphemia]

i'm just asking this because every day in my studio i switch the MB on and the synth is out of tune (e.g. preset A15, the lower sound is about 1-2 semitone higher then the upper sound). The temperature of my studio is 24/7 stable an about 20 degree celsius.

So i have to use the autotune shortcut many times. After about 5min the MB is finally getting in tune. Is it just mine?

I have many analog synth (A6, Matrix12, Moog's etc.) but no such problems with tuning the synth.

Sometimes after autotuning the Brute, the presets sound totally different. So i have to switch off and on the synth again.

Any idea what i can do? How can i check if the MB is not ok?

best, Siggi

I have very similar comments to this.  On start up, tuning is a big issue.  Interestingly, VCO1 and VCO2 are close (VCO2 slightly sharper), but VCO3 is about a FULL tone out.  Auto-tune seems to sort it out pretty quickly.  Has been OK after 5 minutes or so.

And yes, the presets do seem erratic too...

[digidisiggi]

i will check tomorrow what happens after running MB without autotune. But i guess the MB has no background tuning like the Andromeda. I think my MB is faulty. It canŽt be in the year 2017 the analog oscillators are such unstable. My DSI OB-6 and P6 also has no tuning issue at all. I really would love the MB but the tuning issue kills my euphoria. IŽll report.

[BobTheDog]

I just checked mine with a tuner.

I used the master tune knob to get the low C on osc 1 in tune and then tested the range and the other oscillators. My master tune is at around 1:30 for this.

Over the full range of the keyboard OSC 1 note C varies by 5 cents.

OSC 2 on LOW C is 17 cents sharp of OSC 1 and varies by 3 cents over range of keyboard.

OSC 3 on LOW C is 35 cents sharp of OSC 1 and varies by 3 cents over range of keyboard.

So there is some tuning difference between the OSCs but they stay in tune extremely well over the keyboard range.

[digidisiggi]

@BobTheDog: you are a lucky guy and it seems you received a good copy of a MB. Thanks for your report.

best, Siggi

[BobTheDog]

When I turn it on tomorrow I will check from cold and see if it's much different.

[BobTheDog]

Ok just tested from cold.

At power on OSC 1 and 2 are around 1.5 semitones flat while OSC3 is in tune.

After 5 minutes OSC 1 and OSC 2 have come into tune

All oscillators are around 10 cents flat from the readings I was getting at end of day yesterday.

So it looks like the exponential oscillators need at least 5 minutes to warm up.

If you mess around with the autotune in this period you are looking for trouble,

If i was you I would turn it on, wait 30 minutes and then do the autotune. Check its all in tune with a tuner or by ear.

After that the next time you turn it on wait at least 5 to 10 minutes (do not use autotune) and then check the tuning with a tuner or ear, my guess is that it will then be fine.

[DrJustice]

...
If you mess around with the autotune in this period you are looking for trouble,
...

Don't the autotune simply tune the oscillators whenever you hit it, or do things get irrecoverably out of whack if tuned when the oscillators aren't yet stable?

[BobTheDog]

Yes it does.

I'm sure it doesn't go irrecoverably out of whack (I haven't tried autotune when it is warming up), I was just trying to get across the fact that if you do the autotune in the warmup period OSCs 1 and 2 are going to go quickly out of tune as they are gradually going sharper, so from a users perspective its "Hey I just tuned it and now its out of tune again".

[BobTheDog]

Also on warm up OSCs 1 and 2 stay in tune with each other, the real discordance is noticeable only if you have OSC3 going as well or trying to play in tune with something else

[DrJustice]

OK, thanks. Was worried for a moment there

Whatever Moog did with the Sub 37 should be the model for VCO stability and calibration... :-p