cherry audio gx-80 Team Test: Cherry Audio GX-80

[Dave Bryce]

28 minutes ago, KuruPrionz said:

Well, this review is above and beyond

 

Thanks…but we still haven’t gotten to the meat yet. 😏 😁

 

We’ll dig in pretty deeply to the functionality of each section of the synth shortly.  Perhaps there may be some more audio examples - such as the fabulous “Ring Mod Mood” demo brother Jerry laid on us a few posts back - and maybe even some video ones.  🤓

 

We also anticipate/hope that those of you who are reading this will ask us questions and hopefully play along at home, either with your own copy or with the demo version, which you can download from the GX-80’s product page on the Cherry Audio site.  

 

Might even be cool if some programs get written while we’re doing this review, which we’d be pleased and proud to make into an MPN bank and post in our free Downloads area. 😎

 

🥳

 

dB

[MRBarton]

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

[jazzpiano88]

Keith playing the GX1:

 

 

 

 

[Christian Matthew Cullen]

Congrats Dan and the brilliant Cherry Audio team of developers and sound designers that made the GX-80 such an incredibly sounding and expressive instrument! 
 

 I had the utmost pleasure sound designing for it, and I'm telling you - IT’S A BEAST!

 

But Does It Synthwave?! Here is my new track " DRONES IN THE MIDDLE EAST " that was made exclusively with factory presets I created for Cherry Audio (Sounds Famous Bank) , and are included with Cherry Audio's GX-80 Software Synthesizer:

 

 

 

[Dave Bryce]

49 minutes ago, Christian Matthew Cullen said:

Congrats Dan and the brilliant Cherry Audio team of developers and sound designers that made the GX-80 such an incredibly sounding and expressive instrument! 
 

 I had the utmost pleasure sound designing for it, and I'm telling you - IT’S A BEAST!

 

Good to see you here, brother!  Hope all is well with you and yours.  

 

Killer demo - thank you for posting!

 

dB

[Reverend Rhythm]

46 minutes ago, Christian Matthew Cullen said:

But Does It Synthwave?! Here is my new track " DRONES IN THE MIDDLE EAST " that was made exclusively with factory presets I created for Cherry Audio (Sounds Famous Bank) , and are included with Cherry Audio's GX-80 Software Synthesizer:

 

Yes!  It most definitely can Synthwave!  Beautiful demo.

[Reezekeys]

1 hour ago, MRBarton said:

Also, the GX-1 manual is funny on another level.  It's full of little cartoon illustrations and simplistic explanations

 

This one caught my eye - I've seen plenty of woofers and tweeters, but not a single "squawker"!

[mcgoo]

I wonder how well the ribbon on my Polybrute would work as a controller for the GX-80's ribbon. Perhaps Dr. Fortner can weigh in on that.

 

@Dave BryceI'd love to hear more about his the Raven is working as a controller. 

[KuruPrionz]

23 minutes ago, Reezekeys said:

 

This one caught my eye - I've seen plenty of woofers and tweeters, but not a single "squawker"!

I've seen "Squawkers". Now these days we have "weefers" and "twooters" - small speakers that can't quite do anything much. 

I sent a friend a recording I was working on, he played it for me on his cell phone and said "I like that I can hear the bass guitar."

Well, the high frequencies anyway... sort of...

[Dave Bryce]

4 minutes ago, mcgoo said:

I wonder how well the ribbon on my Polybrute would work as a controller for the GX-80's ribbon. Perhaps Dr. Fortner can weigh in on that.

 

@Dave BryceI'd love to hear more about his the Raven is working as a controller. 

 

What do you wanna know?  It’s basically a giant hi-res touch screen.  You flick an on-screen switch/paddle or push a button, it reacts the way you’d expect. Same with the ribbon…

 

dB

[mcgoo]

2 minutes ago, Dave Bryce said:

 

What do you wanna know?  It’s basically a giant hi-res touch screen.  You flick an on-screen switch or push a button, it reacts the way you’d expect. Same with the ribbon…

 

dB

Hmmm, well, that covers the basics! I guess my biggest question may be one only I can answer for myself, but I'd love to hear your take... With the touchscreen's ability to directly access the controls, is the feel when programming / tweaking as natural, or more natural than having controls assigned to a midi controller? 

[Anderton]

6 minutes ago, mcgoo said:

@Dave BryceI'd love to hear more about his the Raven is working as a controller. 

 

Well, I'm not Dave Bryce, but I'm using a conventional multitouch Planar touch screen. It works as you'd expect, with one exception. In Focus mode, moving a slider can also move the focused view. So I hold the window in place while moving controls.

 

An instrument with this level of editability really benefits from multitouch. Even working on the full-size UI is surprisingly agile. And it also feels more like programming a hardware synthesizer. 

 

One of the comments I hear from people is that when using touch, their fingers cover over the control they're moving. However, once you touch a control, you can move your finger sideways and out of the way. The only requirement is that you not lift your finger off the screen between the time you touch the control, and the time you start adjusting the parameter.

[Nathanael_I]

Should be very very nice played from the Osmose. Likely an ideal companion to the Eagen matrix digital engine. 

[EscapeRocks]

I finished the GX-80 Ribbon control on my iPad MIDI Designer Pro. 
 

It took a little bit dial in the specific parameters to make it work the way I want it to work.
First, the connection: I create and ad hoc Wi-Fi network on the MBP, and connect my iPad to that. 

 

Here’s the main screen.
 

This is my Mainstage/GigPerformer setup. 
I use it mostly to launch (play) our walk on track backstage. 
 

Now to the ribbon specifics. 
It is set to max 256 steps

I set the default to 50% on this ribbon. I set it to snap back to this when I ‘release’ it.

While this is a bit like a spring loaded pitch wheel, it is much more expressive. 
Just rolling my finger while pressing the ribbon gives a bit of vibrato.  A bit like a Roli Seaboard. 
 

Tapping it works amazingly well. I can hold a note on my controller, and tap the iPad with 1 or more fingers.  I can mimic guitar-like hammer ons. 
 

Anyhow. Just wanted to share 

 

[Dave Bryce]

1 hour ago, EscapeRocks said:

I finished the GX-80 Ribbon control on my iPad MIDI Designer Pro. 
 

It took a little bit dial in the specific parameters to make it work the way I want it to work.
First, the connection: I create and ad hoc Wi-Fi network on the MBP, and connect my iPad to that. 

 

Here’s the main screen.
 

This is my Mainstage/GigPerformer setup. 
I use it mostly to launch (play) our walk on track backstage. 
 

Now to the ribbon specifics. 
It is set to max 256 steps

I set the default to 50% on this ribbon. I set it to snap back to this when I ‘release’ it.

While this is a bit like a spring loaded pitch wheel, it is much more expressive. 
Just rolling my finger while pressing the ribbon gives a bit of vibrato.  A bit like a Roli Seaboard. 
 

Tapping it works amazingly well. I can hold a note on my controller, and tap the iPad with 1 or more fingers.  I can mimic guitar-like hammer ons. 
 

Anyhow. Just wanted to share 

 

Nicely done, brother!!! 

 

 

dB

[MRBarton]

 

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

[Motif88]

On 11/25/2022 at 1:31 PM, Dr Mike Metlay said:

Just for fun, here's some information on the synth whose design elements make the GX-80 plug-in so unique: the Yamaha GX-1. A lot of people talk about the GX-1 in vague and worshiping terms, but very few people actually know what's going on inside it. So let me school y'all.

 

Full disclosure: a lot of this comes from the GX-1 chapter in my book SYNTH GEMS 1, which was vetted for accuracy by well-known musician and writer Gordon Reid, who owns one of them. (Yes, he owns a GX-1 and keeps it in good repair himself. Long story in there, but not for now.)

 

Having watched most of Dr. Mike’s videos on the Hydrasynth coupled with the release of the GX-80, I will let my wife know that Mike has heavily influenced my combined Christmas & Birthday present to myself in the form of the Hydrasynth Deluxe with a BFCM deal at $1499..Sweetwater payment options make it easier to justify.

[MRBarton]

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.

[Anderton]

Thread Progress Report

 

First of all, a huge thank-you to Cherry Audio and everyone participating (and lurking, too)!!

 

To make this thread as informative as possible, you'll note some changes and edits. For example, there was a question about how to control the ribbon controller. There were a lot of GREAT responses, but they were scattered around in various pages. So, I consolidated them all as answers in the post asking the question. This approach seems much more convenient.

 

Also, I started adding sub-heads, like "Ring Modulator Deep Dive" or whatever. These should make it easier to skim the thread to find topics of interest, or to re-visit specific posts. For example, if you get really involved in programming the Ring Modulator, you might want to review the material that's already been presented.

 

Finally, I've tried to keep posts and responses as close together as possible. If some of the short posts in between were not absolutely necessary (like David Bryce saying "great job, brother!"), I've hidden (not deleted!) them to make for a more compact reading experience. However, this kind of editing happens only after posts have been up for a while. I think those initial reactions are an important part of the discussion, but over time, hiding them makes the thread more manageable, easier to read, and puts the focus on the more recent posts.

 

I hope you find these changes helpful! Thanks again for your participation. Now, back to the review.

 

(And yes, I'll probably hide this post in a week or so...it's just timely right now, to explain why the thread might be looking a bit different.)

 

 

 

[Robert Saint John]

18 hours ago, MRBarton said:

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.

 

haHA! I could only treat myself to the original Hydrasynth this weekend before that sale disappeared. Most expensive controller I've ever purchased, but I hear it includes a nifty synthesizer as well. Who knew Cherry Audio folks would give ASM a sales bump, all for the sake of GX-80? 😁

 

1 hour ago, Anderton said:

First of all, a huge thank-you to Cherry Audio and everyone participating (and lurking, too)!!

 

Guilty, until now!

 

[jerrythek]

GX-80 Ranks Overview

 

OK, let’s start to dive into the panel and voice architecture of this awesome instrument.

 

Looking across the top of the panel are two rows of identical parameters (labeled I and II) that are the heart of the CS/GX-80’s voice architecture:

 

 

In CS-speak each of these are called a Rank, which is a carry-over from Yamaha’s organ-centric lineage. Each of them is a complete synthesizer “voice”, with what at first glance looks like a traditional VCO (oscillator) feeding into a VCF (filter), which is then routing to a VCA (amplifier) for final output. As you dig in deeper, though, you will find a number of unique attributes to each part of this topology. Complicating our quick tour (not that I’m complaining) is the fact that Cherry Audio has merged in a number of parameters that were part of the GX-1, and they thwart my desire to show the voice in as simple terms as possible. These additional parameters are all colored orange to indicate their GX-1 origins.

 

The Oscillator

 

Zooming in to the oscillator section itself, you encounter some of this issue right away. Normally you might think you could go from left to right to understand the controls, but that means you’d be starting with Pulse Width and Pulse Width Modulation parameters before you’ve even encountered the oscillator itself. So let me start by highlighting the oscillator section that comes from the CS-80 first, and then we’ll look at the GX-1 additions. Here are the CS-80 oscillator parameters highlighted in red:

 

 

Starting with the middle highlighted parameters you have a choice of a square/pulse wave and/or a sawtooth. Yes, you can use both at the same time. The section to the left of it is the pulse width control (at 50% it is a square wave), then the amount of modulation you wish to apply, and finally the LFO speed to create the pulse width modulation. Moving to the far right you have a noise generator, which produces white noise.

 

Now, let’s focus on the GX-1 parameters that were added. These are highly unique things that we don’t usually find in an analog synthesizer’s oscillator arsenal.

 

 

To the left of the pulse wave rocker switch we have another pulse wave control, with a volume slider so it can be mixed in. It is labeled HPF because this oscillator is run through a dedicated high-pass filter, whose cutoff is controlled by the slider to its left. What a unique concept, capable of producing some really signature timbres. I’ve got to experiment with modulating/automating that cutoff within my DAW – makes me want a Mod Matrix to be able to route an envelope or LFO to that parameter! But I am getting ahead of myself…

 

To the right of the sawtooth rocker switch is another sawtooth, this one is routed through a band-pass filter. Again, très cool idea. To the right of that is a triangle waveform, pitched an octave higher than the other choices. Have you been keeping count? That’s five waveforms available at the same time, plus noise, per oscillator, meaning it all only takes up one note/voice of polyphony. Keen-eyed observers no doubt notice that there is no tuning control found here, other than the triangle wave being pitched up an octave. In another of the CS/GX/GX-80’s nods to its organ lineage, that tuning is found down in the center of the panel (to the left of the Tone Selector/preset switches), labeled in organ footage terminology.

 

 

 

The Filter(s)

 

 

The GX-80 offers dual 12dB per octave filters, one is a resonant low-pass design, the other a resonant high-pass. Note that the low-pass filter does not self-resonate. Once you start using both of them you are in effect controlling a band-pass filter, and this is certainly a signature part of the synth’s sound. At first glance the filter labels might confuse you, since they all have text marking above them for High, and below for Low. This is just for the slider value/position. Pay closer attention to the bottom text, which more clearly indicates what is what.

 

To the left of the filter sliders is a rocker switch to select between the traditional CS-80 filter and the slightly different GX-1 filter. Dr. Metlay will have more to say on this shortly.

 

The next five sliders are all for the ADR envelope control over the filter. This design is one of the more confusing aspects of the synth’s design, and again, the good doctor will be here shortly to walk you through it. These are followed by a switch to invert the envelope shape for the filter, another capability drawn from the GX-1.

 

I’m including the last two parameters in the filter section, although by design they are labeled as part of the amplifier section. The first is VCF level, which is a mixer stage controlling the complete oscillator topology post filter. A pretty non-standard design, right?

 

The last is a post-filter sine wave, which means that if you’ve been keeping score from before, that’s actually six waveforms available at the same time! This addition actually makes a lot of sense, considering that with all the high-pass and band-pass filtering going on, it could be nice to bring back in some clean fundamental tone to thicken/warm back up your sound. And now the filter level control makes a bit more sense, as you can balance the two elements to your taste.

 

The Amplifier

 

As is to be expected, the next stage of the topology is an amplifier.

 

 

 

A traditional ADSR envelope is available to shape your levels, along with a total level for the voice output. This is followed by a pan control, something that was not available on either the CS-80 or GX-1, but is a logical and welcome addition.

 

Touch Response

 

It is astounding to realize that back in 1976 Yamaha produced a synth (hell, any type of keyboard!) that was touch, or velocity sensitive. Even more mind-boggling is that it also included aftertouch, and polyphonic aftertouch to boot. The Moog Polymoog, released a year earlier was velocity sensitive, but it was a simpler divide-down design, not the fully articulated polyphonic design of the CS-80. The Rhodes Chroma (originally developed by ARP, but never put into production by them) was released in 1982, with velocity sensitivity, and Sequential Circuits released a velocity and channel aftertouch synth, the Prophet T8 in 1983. The same year Yamaha released the DX7.  So these features being available in 1976 is groundbreaking indeed.

 

Sorry, I got carried away – back on topic. The last stage of the Rank architecture is control for the velocity (called Initial) and aftertouch.

 

 

Velocity can be routed to the filter (called Brilliance) and to the amplifier (called Level). The same is true for the poly aftertouch. There are some other places that velocity and aftertouch can be routed, which we’ll get to in due time.

 

A Perfect Pair (of Pairs)

 

The CS-80 has the same dual Rank design as what you are seeing on the screen. Each Rank is capable of 8-note polyphony, so when layered together you don’t lose any polyphony: you then have 16 oscillators layered to still deliver the 8-note polyphony.

 

Both Ranks can be programmed much the same, detuned and saved as a Preset. Detuned… where? Look to the right of the Master Pitch knob in the row below, that’s where!

 

 

 

Or they can be used to produce different timbral elements that are combined into a final sound. Note that Yamaha seemed to use the term Channel and Rank interchangeably, but only used the term CH (channel) on the front panel screening.

 

The GX-80 goes further than this, drawing from the GX-1, with its dual manuals each with two Ranks per manual, to create a four Rank/Channel design which can create more sophisticated, detailed and massive layers, or be used for a split keyboard design.

 

More on that to come shortly.

 

[AnotherScott]

4 hours ago, Robert Saint John said:

haHA! I could only treat myself to the original Hydrasynth this weekend before that sale disappeared. Most expensive controller I've ever purchased, but I hear it includes a nifty synthesizer as well. Who knew Cherry Audio folks would give ASM a sales bump, all for the sake of GX-80? 😁

 

I basically just bought the Hydrasynth Explorer for the same reason... i.e. largely as a small, lightweight MIDI controller with poly AT. And not even an extravagance if it spares me from wanting the Osmose. ;-) Interesting video here...

 

 

 

[Floyd Tatum]

I think this is going to be my Christmas present (to myself) this year.....

 

 

[matted stump]

The manual wasn't entirely clear - can you get HPF pulse without regular pulse and HPF saw without regular saw?

[Dr Mike Metlay]

On 11/25/2022 at 3:23 PM, cherryDan said:

That's a great writeup, Mike. I just want to add that Yamaha doesn't use the word "synthesizer" anywhere in their documentation of the GX-1. In fat, they refer to the analog synthesis technology as "natural sound," a new kind of feature for an organ.

 

Interestingly, the GX-1 isn't particularly great at making traditional organ sounds. You have at most four sine waves per key (if you link the top and bottom keyboards together), so making authentic big 9-drawbar Hammond organ sounds is out of the question.

 

Your Synth Gems 1 book was a great source of information for us at Cherry Audio, as we first explored what made the GX-1 unique. I have to admit that I had all sorts of misconceptions about what a GX-1 was at the start of this project, and I get the feeling that many other people do, too. People expect it to be the most incredible synthesizer they're ever seen. In fact, it's a rather limited preset-based organ, with important performance controls at your fingertips, but absolutely no synthesizer parameter controls. Plus, there are only 10 preset sounds per keyboard.

 

But it unquestionably led to the creation of the CS-80, and that's an incredibly impressive instrument.

 

Dan

Actually, Dan, it was fully programmable at the voice-parameter level, as I explain in my next post. You just needed to have an optional pair of hardware devices that many people didn't bother buying, because the presets sounded so good and the manual-level and global-level controls could do so much with them. Read on...!

[Dr Mike Metlay]

Historical Perspective: Part 2

 

Last time, I described the world that the GX-1 was born into. Now let's talk about the instrument itself. 

 

Once again, full disclosure: much of this information was taken from my book SYNTH GEMS 1 and the associated research that went into it. I owe a great debt of thanks to keyboard guru (and proud GX-1 owner) Gordon Reid for keeping my work accurate and honest, and I'll try to condense it here without making any mistakes...

 

So what precisely was the Yamaha GX-1? Yes, it was an analog synthesizer, but it was designed to play like an organ, and that means it had features that were unlike what you'd find on any other synthesizer at the time, or (with a few notable exceptions) before or since. Many of its capabilities were utterly alien to both organists and synthesists, and taken all together in a package, they set a bar that no other synthesizer has ever reached.

 

That is not hyperbole. The GX-1 is a machine of pure myth and legend. Here's why.

 

One Tone

 

The essential sound element of the GX-1 is the Tone, a single synthesizer voice. It consists of a single VCO through two VCFs in series - highpass then lowpass - then a VCA. What's so exciting about a signal path that's the same as a Juno-60's? Read on...

 

The VCO on the GX-1 is capable of providing a simultaneous mix of up to seven different waveforms. Yes, seven. The first four are a sawtooth wave available both unfiltered and through a dedicated bandpass filter, and a pulse wave with PWM available both unfiltered and through a highpass filter. There are also a triangle wave, a noise source, and a sine wave. Oh, and each of those waveforms can have an adjustable mix of octaves and harmonics within it, just like altering organ tones with drawbars. All of these but the sine are mixable and adjustable in the VCO section; the sine bypasses the filter and is mixed in at the VCA input.

 

[Pop quiz: why would you not put the sine wave through the VCF? Answer below.]

 

That waveform mix, which few if any analog synths can match today, is then fed through the two VCFs. Unlike the CS-80 filters, which are known to be resonant 12 dB/octave designs, no one knows precisely what the GX-1's filter characteristics are, although their behavior can be (and is) modeled.

 

They are calibrated in "harmonic numbers" relative to the fundamental, with a wide range of resonance from gentle to fairly sharp (but not self-oscillating). Even so, all the service manual says about them is that they have a ten-octave range, from 25 Hz up to well beyond 20 kHz - pretty astounding, and one reason why the GX-1 sounds as open and clear as it does. These filters are not identical to the CS-80's; they are in a class by themselves. That's why the GX-80 models both, switch-selectable per rank.

 

From there, the output from the VCF is added to the sine wave from the VCO and run through the VCA. While the VCA has a conventional ADSR envelope, the VCF's invertible envelope is a bit more complex, with Initial Level, Attack Level, Attack Time, 1st Decay Time, and 2nd Decay Time. (We'll discuss this unusual and truly groundbreaking envelope, which is also featured in the CS-80, later on.)

 

Programming

 

If you count up all the waveform switches and amounts, plus the parameters for the envelope stages, you get a set of 26 parameters to control the sound of a Tone. But how do you set them? As Dan just pointed out, there are no controls for any of these parameters on the front panel!

 

Easy as pie! You hook up the GX-1 to an external programmer called the Tone Board, which has all the relevant knobs, sliders, and switches, each one numbered from 1 to 26 with a graphical layout of signal routing and envelope shapes. You then set the parameters until you get a sound you like. Of course, those settings are lost when you disconnect the Tone Board; wouldn't it be great if you could somehow save them?

 

Trivially simple! You now hook up the Tone Board to the Tone Module Setting Box, and plug in a Tone Cartridge. You then gently turn each of the Cartridge's 26 trimpots, one at a time, until the Setting Box indicates that its value matches the one on the Tone Board. You do this 26 times, unplug the Tone Cartridge, slot it into the GX-1, and you've saved all your Tone settings - in a completely analog storage system, with nary a digital microprocessor in sight! Sure it takes forever, but you can do it... and this is in 1975.

 

Many Tones

 

Okay, so this is a bit more than your usual 1-VCO/2-VCF/VCA voice. If a monophonic synth with just one of these Tones had been released in 1975, it would have been a real attention-getter, even if the parameters couldn't be saved in any way. The thing is, the GX-1 had way more than one Tone...

 

Count along with me, kids: A monophonic Solo Synthesizer with its own Tone! Upper and Lower manuals, each one with 8-voice polyphony, and each voice with two layered Tones! Pedals playing a monophonic voice that is made up of three layered Tones, two of them sharing the same program settings! 1 + 8 (x2) + 8 (x2) + 3 = 36 Tones playing up to 18 voices at once... and it was released in a year where nobody had ever heard a synthesizer play chords before. Think about that for a second!

 

And by the way, all of those Tones can be different, because the GX-1 holds a whopping 70 Tone Cartridges, which can be assigned to various manuals with a set of buttons right above the Upper Manual, which when all the routing options are taken into account, offer a whopping 175 possible combinations of Tones. Still holding on there, kids?

 

Playability and Power

 

The pairs of Tones within the manuals can be detuned from one another, with a different amount of detuning for the Upper, Lower, and Pedals. These tuning controls are hidden in a slide-out drawer under the Lower manual. In addition, each manual has its own Brilliance and Resonance controls for per-manual bandpass filters on top of everything else!

 

Want more? The Upper manual can modulate VCO pitch and VCF cutoff and/or resonance by wiggling the keys from side to side; the Solo manual has velocity, pressure, and side to side control, and the ribbon controller above it is calibrated so it has the same range as the manual, so you can slide pitches from key to key.

 

Spring reverb with override for an external stereo effects loop? Check.

Side-to-side knee controller bar to change the variable sustain for each manual, polyphonic portamento for the Upper manual, and more? Check.

Foot pedal and five-function toe switch? Check.

Crappy preset-based internal rhythm machine? Check.

Audio outputs? Ch... wait. Where are they?!

 

The GX-1 has only one audio output: a multipin cable that's designed to connect to the TX-II speaker cabinet, a monstrous 300-pound octagonal speaker tower with nine drivers (15" woofer, four 8" 'squawkers', and four 2" tweeters) firing in a wide arc and powered by dual 120W tube amplifiers. The cable can support up to three of these towers, and assign the manuals in various ways to spread out their sound. 720 Watts of power through 27 drivers including three 15" woofers - the sound is indescribable, capable of filling a cathedral without breaking a sweat. (Which is what it was designed to do. Organ, remember?)

 

Put it all together and you're talking about a synth with three keyboards and 36 voice circuits, each one equivalent to a monophonic analog synthesizer, plus all the manual-level and global circuitry, plus 70 cartridges full of analog components, altogether weighing well over 300 kilograms. Add in the custom stand, pedalboard, and three 141-kg speaker towers, and you have a package with the easily portable total weight of roughly 0.8 metric tons, which can't be tilted when you move it or it will be damaged or destroyed. And even if you could find one, it would set you back probably a quarter of a million dollars in today's market.

 

What about building a modern version of the GX-1 using modern tech? Heh. People have been trying to build a new version of the much simpler CS-80 in hardware for years, and a few people have come close but no cigar... and the circuitry involved in re-creating the GX-1 is many times more complex. Even a major synth maker with access to the necessary tools and resources would never take on such a monumental task - how many would they sell? Would they ever recoup the costs? Aych Ee Ell Ell NO they wouldn't.

 

And why would they bother? No matter how much they spent, everyone would say it didn't sound like the original, and they knew that because they heard the original in a YouTube video of somebody poking at one in a museum and recording it with a cell phone. (Siddown, Poindexter. Yes, I'm talking about you. Suck it up.)

 

And that, dear readers, is why it is so amazingly, brain-meltingly cool that several of the GX-1's unique features have been integrated into the GX-80 software, starting with the relatively familiar CS-80 voice architecture and taking it to unheard-of new places. (Sorry, but Cherry Audio hasn't figured out how to let you control the plug-in with your knee. Yet.)

 

Now it's time for you to scroll back to Jerry's excellent overview of the ranks, to see (among many other things) how the GX-80's layout differs from the CS-80's and how the added GX-1 features enter the equation. Go on, off you go now! Scoot!

 

[Pop quiz answer: because it's pointless. A sine wave has a single frequency; all a filter will do is turn it up or down as the cutoff frequency goes past the sine frequency. So why not just bypass the filter and give it its own volume slider? Hurr durr!  ]
 

[Dr Mike Metlay]

1 hour ago, mate stubb said:

The manual wasn't entirely clear - can you get HPF pulse without regular pulse and HPF saw without regular saw?

HPF pulse and BPF (not HPF) saw are available on their own. Just switch off the pulse and saw waves with the two black switches.

 

Here's an example of front panel settings that give you a combo of filtered waves with no raw waves:

[MRBarton]

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

[matted stump]

Gordon Reid has been mentioned a couple of times. I thought I'd provide a link to his excellent adventure tale of obtaining his GX-1 and having it shipped half way across the world.

 

https://www.soundonsound.com/reviews/yamaha-gx1-synthesizer-part-1

 

And a brief quote about the first time he turned it on:

 

"I can still remember my overriding emotion as I turned the thing on: sheer, abject terror. And, for a few seconds, my worst fears were realised. Then the valve amps warmed up, the start‑up mute circuit disengaged, and I pressed a key.

I suspect that everyone within a hundred‑mile radius of Cambridge heard that first note. With the speakers' internal amps unwittingly set to maximum and the main output volume full up on the GX1 itself, I imagine that its foghorn blast raised the dead right across the East of England."

[jerrythek]

Timwat posted this over in the Keyboard Corner... it's the wonderful Tom Szakaly, known for his ELP tribute band Noddy's Puncture. Tom was close friends with Keith, who shared a lot of scores, performance tips and such with him, and even sat in on one of his pub gigs. And Tom lent his Hammond L-100 to Keith on a number of occasions. I met Tom backstage at the Manticore Hall duo show by Keith and Greg back at the Westbury Fair on Long Island NY. He knows his way around Keith's music, for sure. Wish he had the front panel down...