Since Montage is leveraged so highly from the DX7 including a high level of compatibility with the patches - it's instructive to go back to DX7 (or related products') tutorials. The other day, I found something that was a very complete rundown of the DX7II-FD = slightly "evolved" DX7 with a floppy drive. Although there's a big chunk involving the file/patch management which (thankfully) does not apply to the Montage - the most interesting part is a demo one-by-one and great explanation of what all the sound-shaping parameters do. I was able to refine my understanding of some of the parameters.

It's not a 100% clone, some sound shaping parameters do not apply such as the pitch wheel scaling, glissando (portamento w/scaling), and turning on/off operators since that was always redundant to level=0 for an operator, etc... But for what does match up (which is nearly everything else) - the video is great. You also have to "throw out" a bit of the tutorial which applies to using the buttons/interface - but this is a good perspective when translating DX7 patches from magazines since they organize the information in terms of the DX7 interface. It's even great to see what's missing vs. the original DX7II (note: pitch wheel scaling can be simulated by using pitch wheel as a source for a destination curve targeting pitch - and you actually have more control than the DX7 in this respect . However, glissando is one of those things that cannot be duplicated). Also great to see how constrained the old system was - like having to match up the right cartridge with your sound in order to get microtunings, for example, to match up with your patch - having to lift write-protect from both the keyboard interface and the physical cartridge, etc.

https://www.youtube.com/watch?v=1r8WfV8qpXM

For me, this came from a playlist with other resources:

https://www.youtube.com/playlist?list=PLkD0B3gKpFOIbWWI5XJUSw0xuO9vc9T28

There are tons of other great tutorials out there outside the playlist that cover similar material from different angles.

Hi everyone, I made an FMX patch that I quite like, except that there are some horrible digital noises in the background on the high notes. are there any FM experts here that know what causes highpitched annoying canny sounds and how to get rid of them?

Gabi wrote:

Hi everyone, I made an FMX patch that I quite like, except that there are some horrible digital noises in the background on the high notes. are there any FM experts here that know what causes highpitched annoying canny sounds and how to get rid of them?

"horrible" is in the ear of the beholder, but if there is unwanted results in the high notes, you'll want to determine which operator(s) are responsible for the harmonic results, and using the "scaling" features you should be able to reduce the energy in the high frequency range. The influence of Modulators on Carriers can produce a wide spectrum of results depending on the Coarse tuning, and while it can be wholly constructive in a certain frequency range, it may be over done in another. Scaling allows you to tailor the influence of an Operator across the keyboard... so you can reduce the influence of the culprits as you go up the scale.

Alternatively, you can take a very "analog" approach and assign a filter to the FM-X Part.

The general, non-helpful answer is: "because that's how you programmed it."

"Annoying" and "canny" are not actionable descriptions - although "dissonant" vs. "consonant" may help guide some very specific actions. Maybe "piercing when I play above middle C key" - if just a pitch problem. Middle C as just an example.

Really, the field is a bit too wide to be much help. From a debug standpoint, losing the "on/off" control for every operator makes the process a little more difficult since you need to set levels to 0 to disable operators now. I would start by setting the levels of all my carriers (operators which are on the bottom row in the algorithm's picture) to 0. This matches BM's suggestion (for the FM method). Go one-by-one until the unwanted frequencies go away - then add back the levels of the carriers which did not have any unwanted contribution to the sound. To do this, I would switch performances back/forth so I would lose my current edits and get back to the saved performance - then change the one carrier with the unwanted frequencies to level 0 to verify that is the only one.

Once the offending carrier(s) is (are) identified, you can circle back and work on that one "vertical" which includes any modulators that are "feeding" the carrier (operators above the carrier, connected to the carrier with a line or through other operators that lead to the carrier). You can set the level of the offending carrier to a non-zero value (back to its original) and switch off the modulators for that carrier by setting the closest operator (modulator that is connected directly to carrier) level to 0. This will provide a test to see if the modulator is causing the problem vs. the carrier.

To just affect the final nominal frequency - this will be done at the carrier level. I'm not sure from your description if the pitch itself or the timbre (sound "color") is the main issue here.

I would say start with that - because then I would start to "branch off" with different things to try with their own dependencies.

And like BM mentioned - if the lower range of the keyboard has pleasing higher pitched overtones - while the higher notes have displeasing higher pitched overtones - then you can scale the carrier's output such that the volume of the offending carrier(s) is decreased as you play higher notes.

It may be easier to use a filter / EQ to get rid of the unwanted frequencies - but this circumvents some understanding of FM in doing so. I would recommend using subtractive synthesis (filtering) in conjunction FM (which is additive) only as a means to take a sound you're perfectly happy with on its own right and plugging it into an effect for added tone shaping. Jumping straight to filters may be a quick fix - but it would be better to have the FM-X performance stand on its own without requiring filters - which leaves filters available for shaping rather than fixing. However, if you have a gig tonight you need that sound - filters would be a viable option for the short-term.

Jason wrote:
From a debug standpoint, losing the "on/off" control for every operator makes the process a little more difficult since you need to set levels to 0 to disable operators now.

You are aware that for debugging purposes you have the 8 knobs in the Element / Operator Mute row (the last one) to mute and unmute operators, right?

thank you all. it sounds better now. it was one carrier. weird. how can a single carrier make dissonant noises without even being modulated?
another thing: is there a way to go back to the unedited sound?

Stefan wrote:

You are aware that for debugging purposes you have the 8 knobs in the Element / Operator Mute row (the last one) to mute and unmute operators, right?

I may have noodled around and found that - again, I don't have the board setup so going by memory. Thanks for pointing out the ability to mute operators which is equivalent to op on/off when debugging.

One lack of a common interface for FM-X is (and again, going by memory) a missing "all" screen which would allow for toggling on/off operators like the elements have (sw on/off).

It would be helpful to have an "all" type summary screen - maybe w/carriers in a different color and possibly with the sort order with modulators preceding the associated carrier. On/off would be helpful here for also a touchscreen interface as well as level an freq. Maybe other items if there is room and they make sense. What we have isn't bad - but the "all" screen for FM-X would make the board's interface seem more integrated.

@Gabi - I'd have to be at the board to get a better answer since FM-X is not 2nd nature to me. Using the reference manual (starting at page 131) I can see a few possibilities. Maybe your PEG envelope brings the carrier to "outside" frequencies. Maybe your pitch/key setting is not 100%. Maybe your Pitch/Vel is not +0. Maybe Random Pitch is not 0. Maybe detune is non-zero. Maybe coarse pitch is non-zero. There's plenty of ways. Also, Montage has more than just a sine wave - so you can start with dissonant carriers by the combo of spectral+skirt+resonance.

As far as returning to the previously saved (previous to edits) - my previous suggestion was to just change to a different performance and come back to the FM-X performance you were editing. This is one way. The DX7 allowed to recall the previous saved setting.

Montage has similar functionality. If you press the performance name, you can choose "recall" to bring back a saved copy of your edit buffer. You can press the [EDIT] button until it flashes which will temporarily bring back the pre-edit parameters. Personally, I find switching to a different performance easier if all I'm trying to do is back out the changes I've made. The [EDIT] flashing ("compare" function) is best to see what has changed in terms of settings as you can watch what numbers "move" in each screen and go back and forth (press the [EDIT] button again to bring back your edits).

From the owner's manual:

Recall latest edits: If you are editing a Performance and select a different Performance without
storing your edited one, all the edits you’ve made will be erased. If this happens,
you can use Recall to restore the Performance with your latest edits intact.

[EDIT] button: ... Also, pressing this button while editing Performance parameters
lets you switch between the just-edited sound and its
original, unedited condition, allowing you to hear how your
edits affect the sound (Compare function). The button lights
when the edit display is shown and the button flashes while
Compare is active.

... and:

Compare function: The Compare function lets you switch between the justedited
sound and its original, unedited condition, allowing
you to hear how your edits affect the sound.
Press the [EDIT] button while the Edit display is shown, so
that the [EDIT] button flashes. In this status, the sound
settings prior to editing will temporarily be reinstated for
comparison purposes. Press the [EDIT] button again to
return to the original status.