Every 5th note sounds strange/different

[EwaldKegel]

Hi, since a few months I am proud owner of the OB-6, but because of moving to other studio location only now I have time to explore the synth. I found something that is bothering me on some patches for example patch 048 ('Crush On You'). Every 5th note I play sounds different from 1-4 and the 6th note, like the filter is wider open. Is this normal behaviour or should I be worried something is wrong with the voice chip(s)?

[Paul Dither]

Calibrate the oscillators and filters first:

1. Hold down the manual button and press 0.
2. The front panel LEDs and display begin flashing as the OB-6 performs its auto-calibration procedure. Don’t turn off the power while it’s doing this.
3. When finished, the front panel controls will return to normal and you can play the OB-6 again.

If the problem persists, get in touch with the support: support@davesmithinstruments.com

[EwaldKegel]

Thanks, the calibration procedure itself seems to be problematic as it 'hangs' when the LED shows 'F51'. I have no other way than to switch off the unit. Maybe this F51 is the culprit of my issue? I don't know if it translates to a certain component within the OB-6.

[Paul Dither]

I see. There was another user experiencing this kind of issue with his Prophet-6. He solved the problem by reinstalling the firmware. (Source: http://forum.davesmithinstruments.com/index.php/topic,100.msg12587.html#msg12587)

So you can either try this or get in touch with the support.

[haternob]

OP - I'm wondering how you got on with this issue?

I noticed a similar issue with my OB6 yesterday whereby the tuning of the oscs was flat every sixth note. I went back to it after leaving it on for an hour or so and all of the oscs stayed in tune. Maybe it's just a case of the synth needing to warm up. I know that my Slim Phatty needs 30 mins or so to warm up before it can keep tune.

Perhaps one of the DSI reps can confirm if this is the case?

[Soundquest]

OP - I'm wondering how you got on with this issue?

I noticed a similar issue with my OB6 yesterday whereby the tuning of the oscs was flat every sixth note. I went back to it after leaving it on for an hour or so and all of the oscs stayed in tune. Maybe it's just a case of the synth needing to warm up. I know that my Slim Phatty needs 30 mins or so to warm up before it can keep tune.

Perhaps one of the DSI reps can confirm if this is the case?

Saying it needs to warm up might draw some doubt from DSI engineering as I brought this topic up before.    They say it should not need to warm up.    However,  mine clearly needs to warm up about 15 minutes, at which point I then never have a tuning problem.  I really don't mind the issue - since once it's up and running it does not drift out again.

 I have not noticed tuning issue as you mentioned "every 5th note",  rather just mine is just general out of "tuneness".   I had the f51 lockup once in calibration as well.  I powered down and restarted and it got past that hang up point.

[Robot Heart]

No, the OB-6 does not need to warm up. It has calibration tables that store temperature presets at every 1 degree C, so you should tune anytime you hear it out of tune. This goes for as soon as you turn it on, it will probably mitigate the need to "warm up" to the first temperature stored in your tuning table. Because we store temperatures every 1 degree C, there are many values to store and it will take a while to populate all of them. Rest assured, no warmup is needed.

[Soundquest]

Thanks Robot Heart.   That makes sense.

[EwaldKegel]

Turned out to be a faulty voice card. Received a new one from DSI and issue was gone.

[AlainHubert]

I bought an OB6 desktop version a couple of weeks ago, and I've performed calibrations many many times, from cold start-up right after first powering it up, to fully warmed-up after several hours of using it. But it still is flat for the first 10 to 15 minutes after powering it up and will slowly get back in tune and remain stable after about 20 minutes and on.

I'm used to it by now, as some of my other analog synths also behave this way, notably the Korg Mono/Poly (which is really unplayable for the first 5 minutes), and my Minimoog D which is a little off for about the same length of time.

So I don't believe in this "ready to be played and perfectly in tune all the time" statement from DSI about the OB6. Unless I might have a defective unit ? (it did hang a couple of times on F11 when doing the many calibrations, and had to be power cycled to get it to do it).

All voices sound exactly alike on patch 048 though...

[Sacred Synthesis]

So I don't believe in this "ready to be played and perfectly in tune all the time" statement from DSI about the OB6. Unless I might have a defective unit ?

It sounds as if this is the case.  This is not typical OB-6 behavior.

[dslsynth]

So I don't believe in this "ready to be played and perfectly in tune all the time" statement from DSI about the OB6. Unless I might have a defective unit ?

I would suggest taking a very serious talk with DSI support line on this. Would be nice if you can report back on the results here for the rest of us to know what the trouble was.

[Robot Heart]

Or simply have a pleasant talk with us regarding your issue. We're happy to help get it resolved!

It may turn out you have an issue with a specific voice, though we won't know until proper troubleshooting has been done through our dedicated support channel.

Speaking to your other point, yes, if it is tuned at enough varying temperatures it will be ready to play as soon as you turn it on and it will remain in tune as it heats up. Again, there are 48 values in the temperature tables and we tune at every 1 degree C, so the calibrations can cover a very wide range of temperatures. If your OB-6 is flat in the first 10-15 minutes upon powering on, tune it during this time.

[AlainHubert]

Or simply have a pleasant talk with us regarding your issue. We're happy to help get it resolved!

It may turn out you have an issue with a specific voice, though we won't know until proper troubleshooting has been done through our dedicated support channel.

Speaking to your other point, yes, if it is tuned at enough varying temperatures it will be ready to play as soon as you turn it on and it will remain in tune as it heats up. Again, there are 48 values in the temperature tables and we tune at every 1 degree C, so the calibrations can cover a very wide range of temperatures. If your OB-6 is flat in the first 10-15 minutes upon powering on, tune it during this time.

Thanks for the reply. Yes, I will contact DSI support in the coming days about it, and will  surely let everyone know the outcome. Although it's not terribly annoying, since a few calibrations will bring everything in tune, but having to do it every time I power on my beloved OB6 is not supposed to be.

[Robot Heart]

Agreed, you should not have to calibrate every time you power on. We look forward to hearing from you in Technical Support!

[AlainHubert]

Just a quick update. I've contacted DSI support and Mark Kono has quickly replied and suggested something that I need to try in the next few days to confirm if my unit is faulty or not. But so far, it hasn't made a difference. My OB6 still needs at least 10 minutes to be in tune and, most importantly, stay in tune without having to constantly call the calibration routine during those first 10-15 minutes. Maybe it needs a little more time, still, to "learn" the full temp range.
We'll see. And I'll be sure to keep you posted.

[Soundquest]

Just a quick update. I've contacted DSI support and Mark Kono has quickly replied and suggested something that I need to try in the next few days to confirm if my unit is faulty or not. But so far, it hasn't made a difference. My OB6 still needs at least 10 minutes to be in tune and, most importantly, stay in tune without having to constantly call the calibration routine during those first 10-15 minutes. Maybe it needs a little more time, still, to "learn" the full temp range.
We'll see. And I'll be sure to keep you posted.

 I too just thought of the warm up period as a character, inherent of the instrument.   But then the common mantra seems to be NO warm up needed,  and so now I'm becoming a bit paranoid about it-which led me to contact support recently.   I'm going to pay close attention, re calibrate at few more temp ranges and see what happens.  Can't say I'm optimistic of a change occurring with it though...I had mine closer to a year now.

[AlainHubert]

Well. After a couple of days and many more calibrations, my OB6 is finally learning to correct the pitch as the unit is warming up. It still takes about one minute to get stable, but it's much faster than before. I'm confident that it will eventually be in tune right away in a few more days. The key was to clear the calibration table and start with a clean slate. Then it's a question of time to fill it again, by calling the calibration routine as soon as the synth drifts out of tune. Thanks to DSI support (Mark Kono) for their help.

[Soundquest]

Well. After a couple of days and many more calibrations, my OB6 is finally learning to correct the pitch as the unit is warming up. It still takes about one minute to get stable, but it's much faster than before. I'm confident that it will eventually be in tune right away in a few more days. The key was to clear the calibration table and start with a clean slate. Then it's a question of time to fill it again, by calling the calibration routine as soon as the synth drifts out of tune. Thanks to DSI support (Mark Kono) for their help.

Interesting.  How do you "clear the calibration table"?

[AlainHubert]

By holding down the "manual" button and pressing #3.
WARNING: do that at your own risks. You will need to call the calibration many many times after that, at various temperatures, in order to fill the table again.