[300 voice FM module]

Why would you want a high pass filter for controlling aliasing? Aliasing is usually at high frequencies so a low pass filter would be useful for that purpose.

 

I thought the same thing first time I read this. Most likely he meant LPF...

 

I know it might seem counterintuitive, but no, I meant a HPF. I could have said it better as "certain aliasing related artifacts" as the generic "aliasing" would have most assuming the well known 'digital noise' charateristic.

 

Aliasing is basically reflections of harmonics around the upper frequency limit of the playback clock rate. Often times these harmonics manifest as 'noise' but there are in fact aliasing related artifacts that can manifest as inharmonic subtones as the Nyquist frequency may be harmonically related to some notes but not others. Sometimes these won't be noticed in the static sound, but become especially notable when adding vibrato in certain harmonically rich timbres in the upper registers. They also show up more frequently when using non-sine modulators.

 

One would control "typical" aliasing by the Modulator Output Level Scaling to decrease the index for the higher pitched notes. An LPF as where they've already implemented in the signal chain would have no effect. Individual Operator LPF's would help when using non-sine Modulators, but since there's already the Level Scaling, they're pretty much redundant.

 

Finally, with the non linear phase & amplitude behavior of sidebands to FM Index, in certain key ranges of high Index (bright harmonic content) timbres there are quirks in the relative Carrier (fundamental) harmonic amplitude that an HPF in the 'post FM' signal chain would be quite useful to help compensate.

 

Manny

 

P.S. I almost forgot, something key to the creation of drum / percussion sounds in FM is the the concept of "tuned" or "intentional" aliasing where you use specific fixed frequency Operators in harmonic relationship to the Nyquist Frequency to get timbrally dynamic pink/white noise behaviors. For most of these types of sounds you don't want to want a noticable 'fundatmental' so again, an HPF is useful here as well.

[Yamaha's Vintage Synth Museum]

Such a rich list of synthesis and instruments. Would be so great for them to consider a Oasys/Kronos type instrument... and get some legit reissues out before Behringer or whoever does it.

 

IIRC Yamaha were first doing the multiple synthesis engine Oasys/Kronos thing -- the IMHO very underappreciated EX5. AWM Sample Playback, FDSP, VL physical modeling & virtual analog synthesis systems, versatile controls. Some unfortunate quirks, but really a hidden gem in their history.

 

One thing really cool about how they've set up SynthSpace is all the gear there is hooked up and ready to go. I've been fortunate to noodle around there a couple of times. Next time I get to go down there I'm going to make sure I bring some long MIDI cables as the CS80 has a MIDI retrofit and plan to layer it up with the EX5 and SY99 to redefine "huge"

 

Manny

 

[300 voice FM module]

Definitely some cool potential there.

 

I'm interested how they implement Feedback and Operator Phase.

 

Only 1 LFO and no looping Envelopes is a oversight, as well as no high pass filter which is extremely useful to tame aliasing, but hopefully the overall clock rate will make it less prone to that.

 

I sent them a about a dozen questions and suggestions

 

I want To see the Japanese guy who has been demoing synths online forever demo this.

Hes obviously had Jazz Theory as his voice leading demonstrates, but hes really fun to listen to and watch.

I bought an FS1r just because of him.

As a matter of fact whenever theres something new I try and catch him.

 

Seeing him get excited over the UI would be a treat.

 

I like this but with 300 voices I sure hope its multimbral as in 16 x 16+ cut off notes.

That and the fact its rackmounted is very tempting.

 

Ujiie is great, definitely does some of -- if not the best -- synth demos/overviews out there.

 

FS1r was quite an interesting project. A number of new, unique things done well and some basic & simple things totally underimplemented.

 

Manny