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third and last part of a fm-tutorial for my students.

(11 Votes)
1 (Updated 2 months ago)
July 19, 2022
Reaktor 6


important! watch computing power! on my iMac i7 (8 Core, 3.8 GHz, 32GB RAM, Late 2020) FM-C only runs at a sample rate of 3/4 (33075Hz). my macbook pro (apple silicon M1 Pro) processes the FM-C with 44100Hz - despite emulation via Rosetta2! for whatever reason.

8 voices

8 operators (4 waveforms / noise / wavefolder / saturator / envelope / modulated filter with HP, BP, LP, NO / glide effect / note-range / delay-start (ms or bpm) / modulation (frequency, self, all other operators). each modulator with an enveloped LFO

mixer with status display for all operators

effects (with bypass):
resonance eq. serial (all bands in series) or parallel (left and right columns separated). resonant bands (like serge-equalizer) or linear bands. modulation, feedback and comb filter.
additionally: ring modulator, chorus, delay (ms or bpm), reverb. all serial or parallel.


Kirill Guk
1 month ago
Rayzen 5 , all time freezy , completely unoptimized! It's impossible to work! But beautiful interface, you need to fix it and I will put 5 stars!
Philippe Loiseau
2 months ago
Congratulations, very nice sounding, but as some have noted here, CPU performance seems strange for a such not-hungry-these-days FM synthesis engine. Did you talk with some Reaktor heads in the forum for more eventual optimization options ? But again, bravo
2 months ago
Welp, I see the comments here but I am running this on an i7 and it comes out at around 50-55% CPU where the default is set. Obvi if I went to top sample rate it just might cook my lunch, but this sounds real nice. I think the point is that this is a competent build that is not simply standing on the shoulders of giants (hey I love to stack macros too!) I look forward to the, no doubt, slimmed-down updates. thanx
x x
2 months ago
not usable if you not put the voices down to 4 (but anyways around 85% cpu limit)....i have intel i7 and 16 RAM using Jack audio in Bitwig 4.0.7...but looks cool, great design
2 months ago
@Stf Dugs: i know :-). i wish, i have time enought. i am teaching piano/keyboard at two musicschools (about 50 students per week). the other time i spend für my print- and web-projects ( i discovered reaktor last year while he corona-lockdown - and now i am addicted :-D
2 months ago
It runs just fine on AMD Ryzen7 APU 5700G (8C/16T 4+GHz, TDP 65W). It takes only 4% of the whole CPU. Load is aprox. 50% on single core. Probably only folks with low singlecore CPU score are having problems... Sonicaly, I like it very much. Thanks.
2 months ago
Runs beautifully on my XPS, not at all on my old PC. Glad you shared though, if you roll back a few years in the UL here, you will note folks crying about ens that can run in 8 iteration combos today. This is just on the leading edge of future sound potentials. Surely a frustrating tantalization for many. A future core breakdown makes a nice project for some users. Thanks, sweet sound!
Stf Dugs
2 months ago
Seems interesting but uses way too much cpu,impossible to use an old computer for this. I see most of it is done in Primary,you would save tons of cpu doing this all in Core instead and optimising there. I know there's a learning curve if you are used to building in Primary but it's really worth it!
2 months ago
sorry, wrong links (because oft translation) here are the correct links:
2 months ago
please read my first section: it works fine with apple silicon processors. on intel cpu you must reduce the sample rate (top right corner at reaktor window for example to 3/4 or lower. on my i7 8 Core, 3.8 GHz iMac, it works with 3/4 sample rate. its a very complex instrument. the user interface will take some cpu power. in an early test version, each operator consumed 14% cpu power (x8 = too much :-) ), after i optimized piece by piece, the cpu power dropped to a small single-digit amount. the complex effects section also requires a lot of computing power. You can find the whole story in 5 parts (in German) here:
2 months ago
Cpu overload... could not try. What actually causes so much load??
Laurence Ketchin
2 months ago
Yeah. No kidding about those processor requirements. Looks neat though!
Danen Raas
2 months ago
Processor overload after few seconds.