Audio examples of 'artifacts' or 'zippering'?

I have read quite a bit in this forum about digital ‘artifacts’ being heard when adjusting certain parameters on the Voyager and am now wondering just how bad this ‘problem’ really is.

I have heard a lot of great Voyager recordings and have not noticed anything unusual. If someone could post an example or two so I can understand what is really being discussed, it would be much appreciated.

Thanks.

No actual clips? I’ll take that as a good sign! :smiley:

I have been meaning to make some recordings with my RME and Little Phatty as a controller as Gonga had posted about, but alas, I have not been able to. My wife has been ill and the studio is in complete disarray while we carry on the good fight. One day, though.

-bruce

No worries boose. Glad to hear that you have your priorities in the right place! My prayers go out to you and your family.

No digital artifacts with my Voyager Old School. :wink:

Thanks for the kind thoughts, Jazzpunk. We’re just taking it one day at a time. Our friends and families have made all the difference.

18Watt - I’d be rather concerned if you did hear some zipper noise! :smiley:

-bruce

All the best wishes boose44, for a quick recovery to your wife, so traquillity and happines will come back to your house and family.
Excuse my bad English though…

I hope your wife recovers soon…my thoughts are with you.

Thanks for the kinds word, everyone.

Right now, my wife is 4 weeks post-op and she’s due to start radiation soon. Hair has started to come back after 3 months of chemo so things are looking a little better.

-bruce

Hey Boose…

Keeping positive thoughts for both of you…you do the same…

Best to you and yours boose.

http://danling.com/HotLinks/misc/RME%26Triton.wav

What you hear are a minor third (3 semitones) glissando (using glide/portamento) followed by a pitchbend of the same frequency. Then both the glide and bend are repeated an octave higher. The problem seems to be only with the RME (or a Voyager controlled with a different controller).

After many months of posts here, at the Novation site and at Korg Forums, what I have learned is that most midi keyboards cannot do smooth pitch bends. That’s because most gear does not send out the highest possible resolution of midi data. None of my keyboards do, including my Triton Extreme, which I bought mostly because I thought it would be able to do smooth pitch bends. To my surprise, even the venerated Triton can’t do quality bends. Apparently, most keyboardists don’t mind / notice. Hard to believe, but absolutely true. My Alesis QS8 and Novation X-Station also sound horrible with the Voyager.

My understanding is that the newer Korg M3 and Oasys have advanced circuits that are capable of sending high resolution midi pitch bend data. Nobody here has answered my question as to whether the Moog keyboards control the pitch with midi or voltage, but my guess is the Moog keyboards sound smooth (though there isn’t a single helpful sample at the Moog site). Unfortunately, like a large number of keyboardists, I can’t stand pitch wheels!

What’s perhaps even more astounding, is how I still would never want to do without my mini. Even without being able to solo with it, the bass is so good, it’s worth keeping just for that. Shows how good the instrument is, doesn’t it?

WHen I had my voyager a few years ago I VAGUELY remember hearing some of what is being mentioned here…however; at that time it was really difficult to figure out what was just the synth and what wasnt as I was still new to synthesis. “Is this supposed to do this?” was the question. lol

Eric

The pitchbend is acting full analog in the left hand section.
But because the pitchbend range is programmable and even might use different ranges for positive and negative amount, it is most likely (calling Moog Music to give details here), that the pitchbend is done by using the full 14 bit digital data. Just like it sends out the pitchbend in full 14 bit (max Midi spec resolution for it = 2x 7 bit data bytes = 16384 steps).
It is due to real cheap resistors and kind of being lazy by some manufactures to build pitchbend controllers with only single 7 bit resolution (128 steps).

There’s a problem more related to pitch bend that no one mentioned. Independently of number of bit resolving the analog sweep another factor play a role also more critic. Until some years ago, but I think it is still thru, no one sequencer or expander module whose able to receive in real time the quantity of messages sent from a controller sending the pitch bend message. For this reason every manufacturer used to sampling the pitch bend position in a intermittent mode. It is quite easy to verify. Roland as example in old controller sent the pitch bend every 20ms. This is very important to understand because in this way messages sent to other gears have no mode to be continuous. Also with the maximum of resolution in the A to D side we can’t avoid the jump from a precedent bend position sampling to a successive position sampling. Also if both sampling whose very accurate with 14 bits of resolution they represent two different moments and two different values with an inevitable gap. Is for this reason that the pitch bend message lost in the time the attention in accuracy from manufacturer. I think this is a problem strictly of Moog architecture. In other external gears you have not artifacts exclusively because the manufacturer take care of this aspect and introduce in hardware or in software a smoothing circuit able to render continuous the behavior of instruments. I hope the next O.S. incoming can solve this big problem.

Cheers,

Gianluca

I always wondered why the Voyager didn’t simply smooth the bend. The solution sounds simple - like applying a glide with a very fast response to the bend. If a glide can sound smooth, why not a bend?

I am disappointed that synth manufacturers don’t seem to think printing such specifications are important. When you’re spending thousands of dollars for the best instruments money can buy, you would think such important specs would be available for players to make informed decisions that so directly affect the quality of the sound.

How can you know that? I made a check on a Roland XP50 and there are big steps when you using MIDI pitch bend changes.
To avoid steps on wide pitch bend ranges (two octaves) you need a glide hardware circuit or a special CPU - it’s not so easy to implement the special algorithm in an 8bit micro controller.
RL

Hi Rudi,

You ready know my thought. I don’t’ discuss about the difficulty of such algorithm. Although I don’t think it is so difficult to implement also in an 8 bit microcontroller. But the problem is another. If you simply look at the number of post in the forum related to this aspect you agree a solution must be found and quickly. Want you make a test? Simply try to record a phrase with pitch wheel modulation movement in a P.C. based MIDI sequencer directly from Voyager. No external master keyboard. When you play at record time the Voyager respond very smooth because the pitch wheel information come directly by the inside system. When you play back your trace in the MIDI In of Voyager you can hear clearly the stepping of frequency shift. I never heard similar difference with other Synth. Also in little synth very less expensive. Sure Rudi here we have a problem and the problem must be solved in same manner.

P.S. Did you seen in a recent thread some other people lamented the problem of zero return of pitch wheel leaving out of tune the Voyager. Do you remember? I signaled the midi message do not return correctly to zero position? Some one suggest to him to recalibrate the hardware. How many time hi will be obligate to repeat this operation in future? A potentiometer have normally tolerance of 10% 20% and worst in linearity. You can’t be confident in a mechanic positioning of zero return. Here also you must think a software solution. Normally modulation wheel are translated in midi position via data table with dead zone to avoid unreliable end stroke and zero position. Did you take care of this aspect?



Cheers,

Gianluca

Thanks for taking the time to post that audio example.

I hope someday all this will lead to a fix.

To avoid steps on wide pitch bend ranges (two octaves) you need a glide hardware circuit or a special CPU - it’s not so easy to implement the special algorithm in an 8bit micro controller.

Dear Rudi

A simple difference-based algorithm could do the job fine - you even wont need any differential calculus. So what the f is so SPECIAL about this algorithm? (and why not just putting a condenser in the CV path - it would smooth the CV as well)