MRBarton

Wait - I'm confused. 🤔 Dr. Sigman's GX80 manual has the following thing to say here about the oversampling feature (bold emphasis mine): I'm going to add a little to the above stock phrase: "the higher the setting, the better audio fidelity will be" in your mind because you pushed the button. True oversampling will occur, but I will bet anyone that they cannot tell the difference in a blind test. So what's really going on when a plugin is oversampled? It means that for every output sample, the plugin, the whole plugin, ran more than once (say 3x) generating in between samples. Then, a steep lowpass filter is applied and the signal is decimated (take every 3rd sample) to create the output signal back at the project sampling rate. This example would more than triple the CPU requirement. If there are questionable routines in the software that produce aliasing, there might be some benefit in the oversampling process. However, in the GX-80, the aliasing products are vanishingly small. The GX-80 also contains no non-linear processing that may produce aliasing. Now in Miniverse, the filter and the VCA distort and the software has built-in oversampling to take care of this (that means you don't have to the push the button there either). However, only those components are selectively oversampled. Making the whole plugin, envelopes, LFOs, keyboard and knob processing, etc. run at a multiple of the sample rate is a huge waste (unless your computer doubles as a room heater). The steep lowpass and decimation process is imperfect as well, so you might be causing more problems than you're attempting to fix. So if it ain't broke... Some in the know may assume that control signals like envelopes, LFOs, etc. run at a lower rate than audio signals to save computing power. This was a common practice in both hardware and software digital synths in the past. Who knows? Some may still do it. If that were the case, that would justify (maybe) the use of oversampling to produce smoother control signals. However, every signal in Cherry stuff runs at the audio sampling rate, even a 2Hz LFO. Therefore, you can't get any smoother shooting down another justification to oversample. In conclusion, I speak for no one's work other than my own, but I expect that most modern reputable developers are completely on top of this issue and pressing the shiny oversample button on their stuff is also a waste. I have not tested every plugin. --mb

I just want to reiterate. The oversampling buttons are not "quality" controls. The instrument will sound no better if you use them. You should always run the GX-80 (and virtually every other modern plugin) at the native sampling rate of your project. --mb

You are correct, sir. I know there is a specific reason why multiple MIDI channels is not supported. Unfortunately, that reason escapes me at the moment. Perhaps Dan Goldstein will explain it here.

Just want to say regarding the GX-80 CPU load, it's mostly all about how many notes you are playing no matter how many instances you have up. If you have different instances responding to different MIDI channels (physical keyboards), the fact that you only have two hands will limit the load for you. The GX-1 had two CS-80s worth of hardware, one for each keyboard. To play both from one keyboard (which is equivalent to the GX-80 in DUAL mode), you had to turn on a coupler switch. Using two GX-80s both in SINGLE mode controlled by two keyboards would be equivalent to a GX-1 and would use no more CPU than a single GX-80 in DUAL mode. --mb.

I can tell you that the GX filter uses microscopically more CPU than the CS filter, but I'm sure it's nothing you would actually notice. The new, improved version is without a doubt much lighter on CPU. Running it on my doddering, decade-old machine is proof. In addition to the multi-threading improvements implemented by the brilliant Dan Goldstein, I also trimmed CPU usage in core routines down to the bone. I'm an old school programmer to begin with and instinctively write routines with the intention of relieving the computer's burden as much as possible. It's just that the GX-80 is quite the beast with a lot going on. Here's a tip: If you are not using something, turn it off. If a rank is not sounding, mute it. If you are not using a VCO resonator, set its volume to zero. If you are not using an effect, turn it off. There is sensing everywhere in the software to skip execution of code that makes no difference to the sound. Reducing polyphony is obvious, but by far the biggest suggestion I can offer is don't use the oversampling modes!! They are not "quality" settings and will do nothing to improve the sound. Unfortunately, some customers expect those buttons to be there so they're there. Don't waste your precious machine cycles on them. --mb

Great question. You can model at three different levels. 1 ) Component level: This is where you calculate the currents through all the parts in the circuit. This process is very CPU intensive and converges on the final value for a given sample after many iterations. It is my opinion that anyone claiming to be doing this in their simulations is lying, but I could be wrong. 2) Circuit level: This is where the code imitates what the parts are doing. For example, if there is a linear integrator, the code increments a value. It does not simulate an op-amp with a capacitor in the feedback loop. 3) Terminal analog: This is where you write code that replicates the output (terminus) of a given circuit or system. The code couldn't care less how the circuit accomplished the task. The GX-80 uses a combination of the second and third methods. For example, the way the CS-80 handles velocity and pressure is very complicated and had to be circuit modeled in order to capture the behavior. The sub-oscillator uses method 3. Which method to use comes down to experience and knowing what's important and what isn't. CPU resources are precious and it makes no sense to component model a gate signal.

I have also picked up a Hydrasynth Deluxe. They should really thank us for boosting their sales. Anyway, I know folks have gotten it working with keyboard and pressure, but are having problems getting the ribbon to send messages or respond correctly with the GX-80. If anyone has gotten all that squared away, it would be great if you could fill us all in regarding settings, etc. Thanks. --mb

Wow, me too. I wonder where that poster went. If you want one, just get the Voltage Modular version on sale now for a mere $25 (shameless plug -- I wrote those modules too). Sounds the same, works better, can have as much of any of it as you want = no brainer. https://store.cherryaudio.com/bundles/vm2500-collection#description Besides, it's really fun to mix and match it with the Moog 900 stuff. https://store.cherryaudio.com/bundles/vm900-collection. But the smartest move is to get it all right now (with the Oberheim stuff) in the Year Three Collection for only $65. The value for money is insane. I wish I was younger. Sorry for the commercial and going off topic, but we always get requests asking for the Moog and ARP stuff to be made into plugins. I don't think people realize that Voltage Modular is a plugin and making those synth systems into plugins would just put limitations on them. Attached is the poster I had (have). Same as yours? --mb

Oh everybody's got a story like that if you're old enough. Heck, about 30 years ago I traded an ARP2500 (that's 2500) for a DX-7. In my defense, it had a lot of blanks and the matrix switches were in poor shape, but still.. On a happier note, attached here is a hints & kinks (old ham radio term) document that went out to the sound designers before the GX-80 was released to give them a boost when starting to program all our wonderful presets. It doesn't cover everything, so for that you should look at the documentation here: https://docs.cherryaudio.com/cherry-audio/instruments/gx-80/getting-started, but it does cover what is unconventional and weird about the instrument and those things I thought required clarification. AND HAVE YOU GUYS SEEN THIS? https://www.musicradar.com/news/best-new-plugins-2022 It's barely been out a few weeks and we came in 2nd for best plugin of 2022!! I like to think we came in 1st among instrument plugins because the thing that came in 1st is an effects processor. Thanks to everyone who voted. --mb GX-80-Programming.docx

Hi Steve, You might have gotten a tear in your eye playing the Pirates preset, but I also got a tear in my eye reading your wonderful comments. It's feedback like yours that makes this monumental effort we all went through worthwhile. As is my bent, a tiny correction here. The modulation is not accomplished with the RING MODULATOR. It is the SUB OSCILLATOR working the voice filters with TOUCH RESPONSE -- SUB OSC AFTER increasing the SPEED and VCF depth. The Pirates intro that uses this sound is easy enough to figure out and the rest of the intro is just a repeated (and slightly arpeggiated) C F Bb C chord (top note is middle-C). I used to play Pirates all the way through pretty well, but I've forgotten practically all of it and my chops have kinda fallen away too. Too much typing and not enough playing. I can still manage a pretty mean Tarkus though. I've attached all the presets I used to make my demo recording which is among the others at the bottom of https://cherryaudio.com/products/gx-80 Once again, thanks for your great feedback and rock on! --mb MRB.zip

If you're talking about the opening modulation effect, this isn't precisely reproducible on a CS-80, as explained earlier in this thread. If the GX-80 has sufficient extra mojo to do this, I would love to hear it! I've been in touch with a team member who promised to soon have the patch. Seriously looking forward to that! Challenge accepted. Here ya go. I could have worked on it a little longer to get it perfect, but it's close enough, and it is indeed doable on a CS-80. Preset and demo attached. --mb PiratesIntro.mp3 Pirates Intro.gx80preset

Good ear, Mr. Anderton. It is indeed a Crybaby modeled after a vintage unit I have had for many years. We discussed which wah-wah pedal to model and we all instantly agreed. We wanted it to be a pedal that was around when the CS-80 was around to match vintage with vintage. The wah filter in the CS-80 is some kind of 2-pole constant-Q (I think) type which bears no resemblance to a wah-wah pedal's behavior at all and also sounds terrible. It's debatable which sounds worse, the chorus or the wah. Apparently, having built-in effects (no matter how bad) in a synth was a huge novelty at the time, so it's kind of like a dog walking on its hind legs. It doesn't do it well, but you're surprised it does it at all. Our mission statement was sort of like: Absolute authenticity except in the cases where the original sucks (and customers would be sad). Fortunately, this area was the only "except".

Dan left out one important point. We put in the superior effects because the hardware CS-80 chorus/tremelo effect sounds like a**. Probably the reason Dan never switches it on.

No doubt. The CS-80 is anything but dead tuned. Every voice card is different. Every voice card is different every hour of every day. In fact, every time to bring up an instance of the GX-80, you get a different one.

Huh, I guessed right. Who'd a thunk it?

It's funny you mention this effect from the intro to ELP's Pirates. I too had an ELP cover band in the late 70s. Will Alexander, Keith's keyboard man and general caretaker for many years used to show up at every rehearsal. Years later, through him, I became friends with Keith and he used to come over to the house, we'd go out to dinner, drink too much, play duets and all sorts of stuff like that. I was also backstage every time he was in town, and when he wasn't touring, he only lived about 6 miles away. That whole time was a fantasy dream come true for me. I think he liked me because I really "got" his music and wasn't just a regular fan. They say never meet your idols because you will be horribly disappointed. That definitely didn't happen with Keith. He was great company, generous, and very funny. We always had a good time and I miss him terribly. Anyway, when he quit touring with the GX-1, he still wanted to play Pirates, but had no way of doing that fast filter LFO effect. None of his touring synths would do it, so I built him a rack effect that would duplicate the function. It was labeled "The Warfulator" and had a pedal for LFO speed and a bypass footswitch. I still have the schematic if anyone wants to build another. I have no idea where the original wound up, though it's possible that EMEAPP has it with the rest of Keith's stuff. --mb

I finally understand the thought process behind the envelope, thanks much! You're very welcome. Mind you, this is just my speculative thought process behind their thought process. Who knows what they were really thinkin'?

I would have to courteously disagree here. Yamaha deslgned that filter for a reason... if the controls contain the same information and accomplish the identical task, then why did Yamaha create it when the VCA has a perfectly good ADSR? The "slightly different way" has real significance for sound design, which is why I plan to talk about it when I cover the filters. I'm going to jump the gun before you write more to agree and courteously disagree with you at the same time. Yes, Yamaha did design that filter envelope that particular way for a very good reason, but I will stand by my claim that the 5 controls convey the same information as a "normal" ADSR+amount system. Both designs control the AD&R timing identically, so we can ignore those. The IL (initial level) and AL (attack level) control the envelope height which is usually done with the single amount control. Therefore, both systems do convey the same information and accomplish the same task. The genius part of the Yamaha design is that the sustain level never moves and is always at zero (therefore no need for a sustain control). This is the envelope phase I refer to as the singing tone, the portion of the envelope where sustained notes spend the most time. With a conventional ADSR+amount system, when you raise or lower the amount, you alter your singing tone because the sustain level moves with the overall height of the envelope. You then need to restore it by moving the cutoff control in the opposite direction. With the Yamaha envelope, this does not occur. You set your singing tone with the cutoff control and then you are free to bring in and adjust your envelope however you like without the singing tone ever being altered. It's really very clever, and once you wrap your head around the way it works, using it becomes second nature. Yamaha could have just as easily put conventional ADSR+amount controls on there and the sounds would be the same, but they thought they had a better idea. I think they did. --mb

Nicely done Dave. Just my usual couple of clarifications here. First, to not use the envelope in the ring modulator, it's the DEPTH control you want to zero out, not the ATTACK and DECAY. Second, the four KEYBOARD CONTROL paddles are bipolar in nature (oh dear!). Pulling the LEVEL paddle down will result in a ~6db boost at the farthest key from center, but pushing it up results in ~40db of attenuation. This is usually the preferred direction to go. Ever have a patch that sounded great in the middle of the keyboard, but took your head off when you played up high? This is what these paddles are for. Likewise, you can control the tone contour across the keyboard with the two BRILL sliders. Here's a fantastic thing you can do with these paddles that came to me in a flash when I was writing these controls up. If you set the paddles in opposite ways on the two layers, you can smoothly crossfade from one sound to another as you play up the keyboard! No hard split point needed and it works really well. It's really liberating to play anything you want and not have to worry about where that darn split point is. IMPORTANT TO KNOW: Here's how to use the level keyboard dynamics controls correctly. These are the controls at the far right of each rank. There is a misconception that the LEVEL control just to the right of the VCA envelope is the volume control for that rank. Although it can act as such, that is not its purpose. To adjust the level for the rank, use the two mixing controls, VCF LEVEL and SINE LEVEL to the left of the VCA. (This was an endless source of confusion for me as well. Why are there so many level controls???) There are actually two VCAs in series at the output of each rank. One controls keyboard volume dynamics and the other is for the envelope. The keyboard dynamics VCA is fed with 3 control voltages which are summed. They are the LEVEL control which is just variable DC, INIT LEVEL which is velocity, and AFTER LEVEL which is pressure. At least one of these needs to be turned up to hear anything. If you only use the LEVEL control, it would seem that this slider controls volume because it does by opening the VCA. However, if you turn up INIT LEVEL instead, leaving LEVEL at zero, you will get full range velocity dynamics. If you only turn up AFTER LEVEL, then pressure will take the volume from nothing to full. The LEVEL control sets a fixed minimum volume when using the other two. To get more dynamic effect, turn LEVEL down while turning the others up. Even with LEVEL turned up full, there is a little headroom left for velocity and pressure to take things up a bit further. The two BRILLIANCE control sliders also have a fixed control -- the cutoff sliders themselves. I kept the 4th VCA control voltage a secret up to now for the sake of clarity. It comes from the SUB OSCILLATOR VCA paddle. I hope that explanation was clear. Any questions will be cheerfully answered. --mb

A couple tiny additions/corrections to the Doctor's excellent review of the GX-1. First, there is nothing mysterious or especially unique about the filter envelope. It is an ADSR envelope like any other. It is just parameterized differently. On most synths it takes 5 controls; A, D, S, R, and envelope amount to control the filter. On the GX/CS instruments it also takes 5 controls; IL, AL, A, D, and R. These controls contain the same information and accomplish the identical task, but in a slightly different way. You can create AD, AR, and ADSR envelopes just like with a standard envgen. A quick stroll through the GX-80 manual will fill you in on all you need to know. On the GX-1, the sine wave was included back in the oscillator section. When the CS-80 was made, it was decided to move it post-filter where we have decided to keep it because we think that move was a good idea. And yes, you can filter a sine wave -- attenuating is filtering. There is no global bandpass filter associated with the BRILLIANCE and RESONANCE performance controls. They act as biases for the filters contained in all the voices and affect both ranks. The BRILL control can add or subtract from the filter cutoffs and the RESON control only adds to the resonances. Therefore the default positions for these sliders are BRILL in the middle, RESON all the way up (minimum). Remember, moving the BRILL control affects both the HP and LP filters, but not equally. In general, the HP moves less than the LP. For example, the envelope moves the HP half as much as the LP. This has two benefits. First, it opens up the passband between the filters allowing for a fuller tone, and second, by not having the HP creep up as high, you don't lose as much low end. --mb

What a coinkidink. I just treated myself to a Hydrasynth Deluxe for Black Friday as well. Great minds and all that. Can't wait till it gets here and I can play the GX-80 like it was meant to be played.

So, too young to remember squawkers, eh? We call them midrange speakers now. What about this? See that cone inside the cone? That's called a, wait for it.......a whizzer. They used to be very popular and appeared on large woofers as well. --mb

What I find very funny is that Yamaha touted the "programmability" of the GX-1 as an incredible innovation. After all, who can program an organ sound? Unheard of. To say that the process was long and tedious would be an understatement, and you had to go through it twice to make a single preset. I'm sure you guys will cover that process in detail, but I just wanted to point out that what we regard as unthinkably inconvenient and laborious was being advertised as an absolute boon. Also, the GX-1 manual is funny on another level. It's full of little cartoon illustrations and simplistic explanations, like the instructions for a new toy for a toddler -- a $60,000 toy. Attached here for your amusement. --mb Yamaha GX-1 Owners Manual.pdf

Ring Modulator Deep Dive Stand by for long winded answer about the ring modulator. There is nothing special about the ringmod circuit in the CS-80. It uses a 1496 balanced modulator chip like a zillion other synths. The 1496 is meant for use in radio circuitry and is repurposed for audio use. What makes this ringmod musical is the fixed patch Yamaha has placed it in. As you know, a ring mod takes two input signals and produces a single output signal containing the sums and differences of all the spectral components. In most other synths, these two signals come from two VCOs, both in the audio range. This results in the usual inharmonic, clangorous sounds. In the CS-80, one of those signals is your synth sound and the other comes from a dedicated sine oscillator that has a very wide range, going from sub audible (slow LFO), up into the mid audio. The pitch of this oscillator can be tuned manually and modulated with a dedicated AD envelope generator which can provide a very wide sweep. This sweep triggers on every new key. The opening sting on the old Dr. Who theme is exactly that. Another cool feature is the MOD paddle which is essentially a crossfade from dry through fully ringmodded sound. There are cool effects to be had on the way. If you listen carefully when the mod oscillator is sub audible, you will hear the character of the modulation change in interesting rhythmic ways as you move the paddle. Yamaha was certainly not the first to use a ring modulator in this way. Louis and Bebe Barron made extensive use Louis's hand-built vacuum tube ring modulator on the masterpiece soundtrack to Forbidden Planet. It is absolutely everywhere throughout the score. My brother Fred and I had the privilege of having a private lunch with Louis and Bebe back in the early seventies (yes, we're old) where I relentlessly hammered Louis with questions (he didn't remember much). We have always been Forbidden Planet fanatics, as witnessed by my brother's website, the-robotman.com, where you are invited to spend exorbitant sums of money. Louis's ring modulator with slow modulation is on particular display in this clip at 1:36. I bet it would be no problem to reproduce that sound on the GX-80. Some ringmod and a slow drag down the ribbon should do the trick. I'm more than happy to answer any other questions. I'll get down into the weeds as deep as you like (or can stand). --mb