UPS surprised me and delivered Yamaha Reface DX one day early. Hurray!
As I’ve mentioned before, I owned and played a Yamaha DX21 back in the late 80s and early 90s. (The 4-op, FM DX21 was released in 1985.) The DX21 was the first synth that I took to church. I remember playing string, brass and organ patches.
After I unboxed the Reface DX, my head was spinning. Did Rock Moranis’s mad-scientist dad hit my old DX21 with a shrinking ray? The styling and feel is so DX21 that it was a definite case of déjà vu.
The Reface DX has the same solid feel and build as my well-worn Reface YC. I bought Reface YC in 2017 and I’ve played the snot out of it. I take care of my tools and the Reface YC has held up pretty well. I expect the same from Reface DX.
One difference tho’, the Reface YC keys have become clacky (for lack of a better term). Playing the new Reface DX reminds me of how smooth the YC felt at first. The DX velocity response is nice. The DX is still three octaves, so my major complaint about mini-keyboards remains valid. The Reface HQ mini-keys have a more substantial feel than the Yamaha PSS-A50.
After turning this bugger on and playing — Wow, this is a real instrument, a real synthesizer. The DX stores patches unlike its Reface brethren. I went through the presets and found roughly 20 keepers. I’m not into aggressive so patches like “Wobble Bass” got the ax. I made a chart and took note of target memory locations.
Sound-wise, it’s a very nice 4-op implementation. Eight note polyphony is enough to be dangerous. In comparison, Modal Skukpt SE is four voice polyphonic and I always get frustrated when the fifth note causes note theft. I’m putting the Reface DX through a Yamaha Stagepas100 and it sounds great. The built-in speakers are the same old “courtesy speakers” and aren’t meant for serious use.
The effects section is strong. Reface DX implements two post effects in series. The workflow is simple and direct: Hit the EFFECT button and use the data entry strips/switches to make your choices. There is a lot you can do through effects alone without getting into FM programming.
You all might say, “Late to the party, PJ.” However, I made a conscious decision in 2017 to buy one Reface and the YC filled most of my needs. With YC, it’s organ or nothing and that has always felt limiting. Reface DX is a true synth and covers a lot of sonic territory. Maybe I would have been happier with Reface DX from the start? It just doesn’t matter…
Yamaha Soundmondo
Being late has one advantage, Yamaha’s Soundmondo patch-sharing site is full to the brim with Reface DX programs. I decided to start with Manny Fernandez’s patches — go pro. I honestly don’t have time to wade through a lot of, well, crap.
Speaking of which, there are so many DX programs that Yamaha’s tagging scheme is not sufficient to efficiently filter out irrelevant dreck. People can tick off as many tags as they like — inappropriately so. Worse, Soundmondo game-ified contributions, encouraging people to use more tags than necessary in order to win more ears and likes. These factors make efficient search impossible. Yamaha should limit the number of tags per sound to three, max.
Beyond those negatives, Soundmondo works like a charm with Reface DX. I never used Soundmondo with the YC since pulling drawbars is so natural and immediate. With Soundmondo, I quickly found useable string and brass patches. The workflow is smooth and it’s easy to store a new voice on the DX as long as you know which memory locations to sacrifice. No problem.
My only remaining quibble with Soundmondo is, again, due to scale. Soundmondo uses the scrolling reveal approach to search results and does not return to the last selected result. That means you have to re-scroll through search results all the way from the beginning! Since people over-tagged their entries, that makes for a lot of dreck to scan through over and over again. Tedious.
Quick summary
So, Reface DX is now on sale for $250 USD (MAP). I stayed good to my word and waited for close-out pricing before buying a second Reface. If you can find a Reface DX for $250, buy it. You won’t regret the decision.
What’s next? I’m going to try loading converted DX21 patches from the Reface DX Legacy Project. Soundmondo is a little short on FM woodwinds and I’m going to give the old DX21 sounds another shot at glory.
While waiting and waiting for the Superbowl, I went on a treasure hunt through my archives. I found and scanned a few old Yamaha DX learning resources for people who want to learn FM programming.
Yamaha DX21 Play Book
The Yamaha DX21 Play Book is a more user friendly manual for the DX21. It’s closer to what we call a “user manual” than a stuffy reference manual.
The DX21 Play Book has a bright orange cover and takes the reader through the steps of using a DX21. It concludes with a very basic introduction to DX21 programming, including the FM voice data for Glockenspiel (seriously?) and brass.
The DX21 Play Book came with a cassette tape. Side A is audio covering basic operation and performance memory. Side B contains performance and voice data to load onto the DX21. Welcome to 1980’s technology — digital data encoded as audio. Modems, anyone?
FM preset charts
I hand-copied (!) patches for eight DX21 factory presets. Primitive, but I can still read the results today unlike my variable speed floppy disks for Mac SE. 🙂
Yamaha Aftertouch Magazine
Before YamahaSynth.com and forums, there was Yamaha Aftertouch Magazine. Aftertouch was edited by the talented Tom Darter of Keyboard Magazine fame. Yamaha dropped real money on Aftertouch. I loved that mini-magazine and read it religiously.
There is a great collection of Aftertouch magazines at Yates Family. In the January 1989 issue, you will find a brief bio and comments by a young guy named Phil Clendeninn. (Thanks, Phil!)
Back in the day, Keyboard Magazine published in-depth reviews and how-to articles. That’s why many of us mourn the loss of Keyboard Magazine.
Here is a scan of “How to Program the DX7” by Bo Tomlyn as told to Jim Aikin. Bo Tomlyn was a consultant and clinician for Yamaha. If you read this article and the series by Manny Fernandez, you’ll be ready to go.
Yamaha FM Essential app
Finally, the Yamaha FM Essential app is a quick and free way to check out 4-op FM programming. You need to connect your iPad to a Mark 2 MX series synthesizer to unlock all of its presets (including the DX100).
I unlocked the app — once. Unfortunately, if you archive the app to iCloud, it loses the unlock data. So, the FM Essential app is now locked again.
Hey, Yamaha! Maybe it’s time to fully unlock the FM Essential app for everybody? I can’t find an MX at a local store to do another unlock. Maybe unlock the app when its connected to any Yamaha synth?
If you’ve browsed Yamaha Reface at on-line retailers, you’ll know that Reface DX and Reface CS are currently on sale. The DX and CS are the two Katzenhammer kids which share the same internal design, using a Yamaha-proprietary SSP-2 processor as the central compute engine.
The Reface DX price is startling: $250 USD (MAP). Wow! That’s the price of a mid-range guitar pedal. Makes me wonder if the DX and CS are being closed out or if Mark 2 models are in the works. The venerable SSP-2 is supplanted by the SSP-3 and perhaps the inventory of SSP-2 is depleted.
The Reface CP and Reface YC MAP prices remain the same. I suspect that sales of these models remain solid as there always seems to be a need for good EP and organ sounds.
That DX price is a clearance price. When Reface was released, I vowed to buy at blow-out pricing. Yep, I put a Reface DX on order.
A few Reface DX programming links
First off, I’m amazed at the number of contributed DX patches at Yamaha’s Soundmondo sharing site. There are literally thousands of Reface DX patches. The Soundmondo tagging idea is good, but too many punters over-tagged their submissions. I’m looking for “orchestral” sounds and there are many tagged patches that are not remotely “orchestral”. A search system is only as good as the quality of its tagging.
If that’s not enough patches for you, try the Reface DX Legacy Project. Martin Tarenskeen maintains this vast library of Reface DX patches converted from old FM machines. I can’t vouch for the quality of the conversions (yet), but I’ll be heading there for old 4-op DX21 patches. I had a DX21 back in the day, and know the factory sound set quite well. I still have the original cassette tape with DX21 patches on it!
I also plan to do a little FM programming. This series of articles by Manny Fernandez is excellent:
Reface DX is old enough to be a grown up by now. So, there’s plenty of on-line support if you choose to jump into the Reface DX pool.
Yamaha SEQTRAK FM
I was curious to see how SEQTRAK FM stacks up against Reface DX. My conclusion — it’s the same FM engine:
4-op, 12 algorithms, polyphony 8
Same algorithms and parameters
SEQTRAK includes many Reface DX patches
Looking beyond FM, SEQTRAK does AWM2, sampling and sequencing, and offers more effects. I’m more of a player than a button-pusher, so Reface DX is better for my personal needs.
Reflecting on the SEQTRAK FM and AWM2, I would expect to find a Yamaha proprietary SWX09 at its heart. The SWX09 core executes the Renesas SH architecture, same as SSP. Plus, SWX09 has an integrated AWM2 tone generation engine.
Spot product shortages have sparked speculation about discontinued products, new products, etc. Given the human propensity to look for and find patterns, it’s no wonder that conspiracy theories take hold!
The on-line inventory picture is mixed. Some retailers show Yamaha Montage/MODX, for example, in stock, some show them out of stock pending September availability and, in one case, discontinued.
Random “discontinued” tags seem to come and go. A month ago, the Yamaha Canada site marked the MX as discontinued. Now the marker is gone. Better indicators are blow-out pricing to move stock or a Yamaha spiff incentive to move old stock. So far, I haven’t seen any clearance pricing or promotions.
Yamaha’s mid- to upper-end keyboard products have a vulnerable supply dependency on Asahi Kasei Microdevices (AKM) DACs and ADCs. The AKM factory fire was worse than originally thought and production is still not back on-line. Renesas has offered to manufacture AKM devices. The Yamaha UK site has the disclaimer, “Due to the difficulty in procuring semiconductors and procuring parts worldwide, some of our product area deliveries may be delayed. Thank you for your understanding.”
AKM aren’t very public about their recovery and certainly haven’t released a public roadmap. A recent press release for VELVET SOUND DACs and ADCs mentions sampling (no pun intended) in January 2022 with “mass production scheduled for the third quarter of 2022.” Given that Toyota is a top AKM customer, who wins, Toyota or Yamaha? 😉
The AKM shortage inspires other conspiracy theories, too. Theory #1: Yamaha are using non-AKM DACs and ADCs in Montage — the analog/jack (AJK) board was redesigned or manufactured with inferior non-AKM devices. Theory #2: MODX is suspended in order to give preference to and ship the wider-margin Montage. Someone went so far as to ask about replacement DACs in Montage and got the usual non-response from Yamaha. (What did they expect?)
Some of the Yamaha boards use Yamaha proprietary ICs, e.g., SWL, SWX, or SSP2 processors, creating a different supply dependency. When production inventory is exhausted, Yamaha need to re-spin end product to use a newer part. The July 2016 MX refresh is one interesting example. I believe that was the case with the MX refresh.
I haven’t seen a new version of the heavy weight SWP70 tone generator. However, Yamaha have updated both the SWX and SSP lines:
The SWX08 is replaced by the SWX09.
The SSP3 — now appearing in Steinberg and Yamaha pro audio products — will likely replace the SSP2.
Are new product spins in the works? Something is coming (eventually) given the CK61™/CK88™ and AN-X™ trademarks. Once again, only Yamaha really knows. 🙂
Oh, did I fail to mention, I added an Arturia Keylab Essential 49 to my iPad rig. I wanted a super light-weight MIDI controller with knobs, sliders, and a minimum of 49 keys with good action. The Keylab Essential 49 fits the bill at 6.6 pounds (3kg), eight pads, nine encoders and nine faders (sliders). The street price is attractive, too: $229 USD. I had a good experience with the Arturia Keystep 32 and decided to give the Keylab Essential a go.
Why the Keylab Essential after Korg Microkey Air joy? I gave the Air’s mini-keys the old college try and then some. First off, most mini-key instruments are three octaves and too short for two-fisted playing. The Microkey Air 49 has four octaves, making it much easier to play most tunes without finger gymnastics. [If you’re a pianist, we’re not even having this conversation!] Although the Microkey Air has Bluetooth MIDI built-in and is battery-powered — genuine plusses — it doesn’t have knobs/sliders for VST control. And, well, it still has those mini-keys.
Arturia Keylab Essential 61
The Keylab Essential 49 is only three inches longer than the Microkey Air: 30.9″ versus 27.9″. Sure, the Keylab Essential is twice as deep, but them encoders and 30mm faders have to go somewhere! I will admit, the Keylab Essential is not a “lap board” like the Air; it needs a proper stand and power source.
The Keylab Essential key action is decent enough. Like the Keystep, it feels a bit soft. If you want a fast, crisp action, this isn’t the droid you’re looking for. Even though the Keylab Essentials are Arturia’s budget line, the encoders and faders feel sturdy with a reasonable amount of resistance.
I’m happy with the Keylab Essential and, yes, I’ll be keeping the Microkey Air, too. Here’s my short Keylab Essential wish list:
Battery power
Bluetooth MIDI
Expression input, not simply sustain (on/off)
Then again, the price would be higher and/or the build quality would be lower. No free lunch.
Analog Lab
I’m mainly interested in iPad (IK BX-3) and hardware (YC and Skulpt SE) control, not PC-based VSTs. However, Analog Lab is a fun leisure destination. Analog Lab and its integration with Keylab Essential are simply brilliant. Prepare to waste long hours jamming away with the best sounds of yester-year with lots of knob twisting and fader slamming.
Controlling Yamaha Reface YC
Yamaha Reface YC is one of my keeper keyboards. It’s been a handy companion at rehearsals and even a few church services. You’ve already heard my gripe about three octave mini-keyboards and Reface YC occupies that doghouse. No need to repeat.
Fortunately, Keylab Essential is almost made for Reface YC. [Dreamers, Yamaha has a full-size YC; forget a Reface re-issue.] Keylab Essential has a 5-pin MIDI OUT which links to the Reface YC dongle MIDI IN. Thank heavens for 5-pin MIDI.
Arturia provide their MIDI Control Center (MCC) app for configuration. The Keylab Essential has eight configuration slots: Analog Lab, DAW and six user slots. MCC communicates with Keylab Essential over USB. Fortunately, the 5-pin MIDI OUT operates concurrently with a USB connection back — no either/or.
Obviously, the faders map to the YC drawbars. Fortunately, the Keylab Essential faders have a drawbar mode, flipping low and high values. The Reface YC drawbars are controlled by MIDI continuous controller (CC) messages CC#102 to CC#110. It’s all right there in the Reface Data List PDF available on the Yamaha Web site.
Amazing how many people will ask a forum for such info. Please RTFM.
The rest of the front panel controls — waveform, rotary speed, vibrato/chorus, percussion, and effects — are under MIDI CC control, too. Keylab Essential has three switches (Part 1, Part 2, Live) which are mapped in the following way:
Vibrato/chorus select (CC#79)
Percussion on/off (CC#77)
Percussion harmonic (CC#112)
The switches are configured as toggles, so that the switch LEDs indicate individual switch state.
Rotary speed is interesting because Reface YC has four states: OFF, STOP, SLOW and FAST. By default, Reface YC modulation (CC#0) switches between SLOW and FAST. As an alternative to the wheel, I assigned OFF, STOP, SLOW and FAST to pads 5 through 8. It’s a shame that Keylab Essential doesn’t support radio buttons. If it did, one could make each pad in the group a toggle showing the current rotary speed state.
As I mentioned, Keylab Essential does not have an expression pedal input. Thus, I route a Yamaha FC-7 expression pedal to Reface YC directly. The Keylab Essential sustain input is still useful, however. I attach a sustain pedal and assign the sustain input to rotary speed (CC#19: SLOW and FAST). Momentary switch mode allows quick changes and speed bumps.
It’s worth noting here that rotary speed has four settings:
CC#19 Value ---------- ----- 0 - OFF 0 1 - STOP 42 2 - SLOW 85 3 - FAST 127
Switching between SLOW and FAST means changing CC#19 between 85 and 127.
Making the rest of the story short, the remaining Reface YC parameters are assigned to the encoders. Waveform, vibrato/chorus depth and percussion length have five discrete settings each, i.e., they do not sweep continuously across 1 to 127. Expect to hear discrete changes (steps). The step values are: 0, 32, 64, 95, 127.
Vibrato/chorus does not have a Reface on/off switch. Vibrato or chorus are OFF when the vibrato/chorus depth is zero.
Here is a table which summarizes the control mappings:
-------------------------------- ---------------------------------------- Reface YC Arturia Essential 49 -------------------------------- ---------------------------------------- Rotary speed 19 0-127 Mod wheel, Pad 5-8 OFF, STOP, SLOW, FAST Wave 80 0-127 Knob 1
There’s been an extended discussion in the YamahaSynth.com Montage Forum about the ability to add Virtual Analog (VA) synthesis to the current Montage and MODX platforms. It’s been a good discussion and it encouraged me to jot down a few musings about the hardware support for AWM2 and FM-X.
In case you don’t visit YamahaSynth.com, I reposted my musings here and added a diagram or two.
Before saying anything, I have to emphasize “Speculatively speaking.” With as much invested in AWM2/FM-X and their implementation in silicon, Yamaha have not published about the internal design. This whole discussion — including my own comments — would be on much sounder footing (no pun intended) if the micro-architecture were published. Yamaha are tight-lipped so “Hah!” to us all. 😀
BTW, we’re lucky that we can speculate at all since Korg, Nord, etc. have largely buttoned up their service manuals.
I’m skeptical
I’m skeptical about adding VA through an update given the current platform because of limitations in the current synthesis pipeline.
Yamaha regard their expertise in large scale integration as a strategically important asset. (Please see their annual financial reports.) The SWP70 is a major investment in the future. It’s a generational step and a design with a long expected life time. A long life is needed in order to recoup Yamaha’s investment. Thus, we haven’t seen all of its potential capabilities as yet.
At some point, the current hardware platforms (Montage and MODX) will limit the features which can be delivered solely through software. That will necessitate a new hardware model in each product line. Speculatively speaking, I’m not sure if the SWP70 is capable of CS-like VA synthesis. The Reface CS (and DX) employ a Yamaha SSP2 (SH-2 CPU core) for synthesis. The mere presence of an SSP2 in the Montage is not significant for VA because it clearly supports UR-like digital audio in the existing design.
Of course, business decisions will take precedence eventually. We all love the free updates and improvements in our instruments. (I certainly do!) Like cellphones, tablets and other high-end electronics which enjoy periodic updates, we will need to buy a new upgraded platform in order to fuel the future. Nobody rides for free forever.
My mental model
I suspect that we nerds (and I mean that as a compliment!) have different architectural models in mind as to the SWP70 internals. One model is the “standard DSP” model — a pipelined single instruction, single data (SISD) CPU. Naturally, there may be enhancements for vector processing instructions and so forth.
An example of such a generic model is the Yamaha SSP2, which consists of an SH-2 DSP core and several effect DSP processors. The SSP2 is the heart of Reface CS with an internal clock of 135.4752MHz (a multiple of 44,100Hz, BTW). Another example would be the DSP56362 in early Nord/Korg modeling keyboards. The Reface CS manages 8 voices of polyphony (using the word “voice” loosely) with the effects handled by the SSP2 effect DSP processors. (The effect DSP processors are mini, small core, reprogrammable processors.)
The architectural model which I think is used in the SWP70 is a SIMD architecture more akin to a GPU. The Montage/MODX DSP RAM and wave work RAM memory clock is 95.9616.MHz, also a multiple of 44,100Hz. The SWP70 pumps out a finished sample every 2,176 memory clock ticks. The internal clock is probably a small multiple (maybe two) of the memory clock. Everything needs to run in a modest power envelope without a heat sink, etc., so it’s not possible to run at GHz rates.
After writing this, I realized that the AWM2/FM-X synthesis core may not have an instruction stream at all. It might be a block of 1 to N dedicated pipelines where each pipeline is, roughly speaking, an AWM voice element.
I image a block of tone generation (TG) cores dedicated to AWM2/FM-X. Part of that “dedication” is a pipeline specifically tailored and tuned to AWM2/FM-X. (I believe this design IP (the basic core design) is re-used in other AWM2 products.) Yamaha are in the AWM2/FM-X business so it makes sense to design hardware specific to these tasks. It’s no simple feat to produce 128 channels of tone generation with low latency and no burps and hiccups.
I don’t know how much flexibility is built into the so-called “oscillator” part of a TG core pipeline. Could Yamaha write a new SIMD program for VA using the existing TG core design? I don’t know and hence, my doubt.
That said, since Yamaha haven’t published a darned thing and my job easier (Hah!), I could be totally wrong. Yamaha are smart engineers, especially at the hardware level.
The choices made for Reface may or may not be revealing. Reface YC/CP use the SWX08 for AWM2/SCM synthesis. The SWX08 — in my imagination — use a similar AWM2 TG core assist. Reface DX/CS use SSP2 and its SH-2 core. Was something missing in the SWX08 TG core which was available later in the advanced SWP70 cores? Did SWP70 become VA capable as well?
Example: Yamaha YMW820
The closest I’ve ever gotten to understanding Yamaha’s approach to AWM2 is by studying the datasheet and MIDI spec for the YMW820 (NSX-1). Admittedly, the YMW820 is a low-end device implementing a large subset of the XG voice architecture with only chorus, reverb and a single variation effect.
YMW820 (NSX-1) block diagram
The YMW820 has a control CPU (dual issue, 32-bit RISC), mixer hardware, DSP for effects, and a “wavetable synthesis core” (Yamaha’s exact terminology). Both the synthesis core and DSP are controlled by the CPU.
The wavetable synthesis core supports 64 channels (polyphony). The YMW820 has a 2MByte wavetable ROM which presumably contains the General MIDI waveforms. It also has a 3 MByte wave RAM which can be loaded with eVocaloid waveforms or Real Acoustic Sound (Articulation Element Modeling).
The 64 channel synthesis core is drawn as a distinct hardware subsystem from the effects DSP. Each channel is what we consider an element: pitch generator, oscillator, digitally controlled filter (DCF), envelope generator (EG), LFO. I suspect that other AWM2-based products have similar wavetable synthesis cores, including the SWP70. [Click image below to enlarge.]
YMW820 (NSX-1) synthesis core and effect DSPs
Of course, the SWP70 synthesis core is the ultimate in the entire AWM2 family. It also has many effect DSPs for system and insertion effects.
Bottom line, Yamaha exploit massive parallelism for AWM2 synthesis where each channel is a wavetable synthesis element. A true DSP processor like the SSP2 is better suited for VA synthesis which is why the SSP2 is deployed in the Reface CS, not an AWM2-oriented SWX processor. (The SWX has an embedded wavetable synthesis core, too.) I believe that Yamaha will need to add another SSP2 (or some such) to the Montage in order to implement VA. There’s a reason why it’s called a “Standard Wave Processor” — it is hardware specifically designed for AMW2, FM-X, AEM, and SCM synthesis. It isn’t a general purpose programmable DSP. Maybe VA can be warped to the existing pipeline(s), maybe not.
BTW, the new VCM MINI FILTER and MINI BOOSTER are DSP effects. The effect DSPs are programmable — the AWM2 channel filters likely are not.
Big DSP vs. little effect DSPs
I tend to think of the internals as a tone generation front end followed by a flock of small DSP units in the mixer/effects back-end. This seems to be the canonical Yamaha pipeline. In Montage/MODX, some of the small DSPs are routed as insert effects and some as system/master effects. (The effect routing in Genos, BTW, is different and probably different in the high-end digital pianos.) I suspect that the data flow is predominantly (solely?) front to back.
I don’t really know if the small effect DSPs are general purpose or not.They are probably small simple cores because an SWP has at least 15 and real estate is limited. (Lower capacity parts like the SWXs and SWLs have far fewer small DSP cores.) A small core may not have much throughput and the front-to-back dataflow might prevent feeding data from the DSP cores back to the filters, etc. in the front-end.
There is also the issue of getting note and controller data to the effect DSPs in the back end. Note and controller data are delivered on the E-bus directly from the key, knob, slider, etc. scanning processor(s) to the tone generation core. Does all E-bus data get back to the small DSP cores? Certain some data gets through as knobs, sliders, etc. can tweak effect parameters in real-time.
Overall, even as a consumer, I would be happier with a dedicated SSP2 for VA. The VA SSP2 would inject its digital output stream into the existing mixer/DSP infrastructure. [The SSP2 vocal harmony processing does something like this in Tyros5.] The VA SSP2 gets its own DSP RAM and NOR flash for program, and the processing is totally out of the way of FM-X and AWM2. It would be possible to implement different VA algorithms without making compromises. Yamaha could periodically offer new engines as updates/upgrades.
If you’re an ARM aficionado, you might be thinking “big.LITTLE”. It’s a similar concept. Engineers need to make best use of limited real estate. Yamaha need lots of little DSPs for insertion effects. The SSP2 itself is organized as a big SH-2 DSP core and several little effect DSPs (plus a digital mixer). The mix of channel strip and guitar effects is limited.
Down memory lane
The discussion took me down memory lane to the venerable AN-200 and PLG150-AN. Both products use Yamaha’s AN (Analog Physical Modeling) daughter card. I love the old AN-200 and keep one handy. It is a pretty decent approximation of a five voice Prophet 5.
The daughter card contains two Yamaha LSI components:
YSS-236-F: An enormous 160 pin QFP for analog synthesis
YSS-233-F: A merely huge 128 pin QFP for mixing and effects
The 236 is also known as the “VOP3” and the 233 is known as the “MDSP”. The MDSP is deployed in the PLG150-DX daughter card, again in the mixing and effects role. The An1x, by the way, has two of each, implementing ten voice polyphony.
Some sites ascribe synthesis to the Hitachi H8/3002 on the daughter card. This is wrong. The H8/3002 is the microcontroller that issues commands and maintains digital communication with the mothership. The VOP3 does synthesis.
The VOP3 moonlights as the vocal harmony processor in early arranger keyboards like the PSR-9000. The VOP3 is the predecessor to the SSP and SSP2. The SSP and SSP2 subsume the mixing and effect DSP roles of the MDSP. Such is the march of large scale integration (LSI) fabrication technology.
Given this history, I’m not surprised that Yamaha chose the SSP2 for Reface CS.
I like surprises
Watch, Yamaha will come up with something completely different. 😀 Maybe an SWP71. There were different spins of the SWP50 family, so why not? 🙂 From the marketing point of view, demand for VA is sufficiently high that they may require everyone to buy a new platform anyway. Perceived value means “mo’ money.”
I finally had enough time ‘shedding with the Yamaha Reface YC to have the confidence to take the YC to rehearsal with me. [Click images to enlarge.]
I need to write a long review, but here’s a few quick thoughts.
The Reface YC makes a good, lightweight rehearsal rig. Usually, I need strings, horns and a few woodwinds in addition to organ to cover our repertoire of liturgical music. However, I dialed in 608400000 for most of the non-organ church tunes and covered things reasonably well. Slow rotary or clean were enough. For the gospel tunes, I threw in a little 1′ and 2′ to brighten the sound. Nothin’ major.
One advantage of the mini-keys is the ability to kick the SPEED switch while holding a bass note. It took some ‘shedding to get used to the narrow width of the mini-keys. Even though I had enough range for most tunes, three octaves ain’t enough. I really wish the YC had four octaves. Think Harry Connick Jr. rocking a Reface CP on Fallon: “There’s not a lot of room. But, I’m havin’ fun.”
The YC drew favorable comments from both the MD and our pianist. (Thanks John, Margie and Steve — bless you.) The small, light rig got a few envious looks as folks carried out their guitars. (Envy is a deadly sin.)
That’s a JBL Charge 2 portable speaker in the bag. I shut off the YC’s internal speakers and play it through the Charge 2. Its passive radiators do a pretty decent job of bass reproduction. I’ve been kicking simple bass lines with my left hand and the JBL Charge 2 is just enough for our (mostly) acoustic rehearsals. Surprisingly, no break-up with full organ chords either.
The whole deal is battery powered. If I had enough shed time before our annual outdoor service, I might have played the Reface YC instead of schlepping the MOX6.
The Yamaha Reface series keyboards have a small DIN-6 connector that carries both MIDI IN and MIDI OUT signals. The keyboards ship with an adapter that converts DIN-6 to two standard 5-pin DIN connectors. Plug in the adapter cable, connect with standard MIDI cables, and you’re good to go.
A few people on the Yamaha Synth site inquired about the Reface MIDI pin-out. Their questions piqued my curiosity leading to a dive into Yamaha service manuals. The results are posted below along with some essential background information about MIDI signaling.
Use this information at your own risk. That goes for anything on my site!
Although I’ve assembled many boards and kits, I make horrible cables. I much prefer to use commercial MIDI adapters and cables. Life is too short to debug and repair shoddy, unreliable cables. Plug and play solutions are the most flexible; you never know when you’ll need a different configuration of female sockets and male plugs. Adapters like the Yamaha Reface adapter are the most flexible, reliable solution although they are product specific.
The Yamaha part number for the Reface MIDI adapter cable (MD6P-DIN) is ZP893500. If you are a USA customer, you can order the cable on-line from Yamaha 24×7. Last I checked, the cable is also available from the on-line retailer Full Compass. I’ve ordered from both Full Compass and Yamaha 24×7 in the past and they both get a thumbs up.
MIDI background information
If you’re going to do anything with MIDI hardware or software, I strongly recommend becoming a member of the MIDI Association. Please take a look at the MIDI circuit reference design:
This is the original electrical specification diagram. It’s good enough to understand MIDI operation. The original circuit has been superceded by version 1.1 which includes important additions for 3.3 Volt operation and reduced radio frequency interference (RFI). Register to become a member and download the new reference circuit.
As the MIDI specification notes, “The MIDI circuit is a 5mA current loop; logical 0 is current ON.” The MIDI sender and the MIDI receiver are optically isolated. The sender (MIDI OUT) controls an LED embedded within the receiver’s opto-isolator (MIDI IN).
The DIN connector on the MIDI OUT side has the following pins:
Pin 1: No connection (NC)
Pin 2: Ground
Pin 3: No connection (NC)
Pin 4: Connected to +5V (3.3V) through a current limiting resistor
Pin 5: Serial data output (UART TX)
The DIN connector on the MIDI IN side has the following pins:
Pin 1: No connection (NC)
Pin 2: No connection (NC)
Pin 3: No connection (NC)
Pin 4: LED anode (+)
Pin 5: LED cathode (-)
Pin 2 may optionally be connected to ground through a capacitor. Please see the current MIDI specification for more info. (Become a member!)
The goal is to turn the opto-isolator LED ON and OFF. The LED polarity (direction of current flow) is important. The MIDI sender turns the electrical current ON and OFF, that is, it turns the LED ON and OFF. This action sends a serial stream of bits from the sender to the receiver.
While writing, it occurred to me — the MIDI Association never formally named these signals. Thus, you get my names like “the thingy connected to the anode of the LED.”
Example: PSR-S910
The following diagram is the MIDI IN and MIDI OUT circuit within the Yamaha PSR-S910 arranger workstation. [Click on the image to enlarge.] I went back to this older product because it uses a transistor pair on the MIDI OUT side, just like the Reface series. That should make it easier to match up the MIDI signals with the Reface DIN-6 pins. Recent products employ a logic gate instead of a transistor pair to switch current through the MIDI loop.
Please note that the S950 MIDI signals are exactly what we expect knowing the MIDI reference design. The “extra stuff” suppresses RFI among other things.
Example: Reface CS
The diagram below depicts the Reface CS MIDI interface circuit (with a few edits for brevity and format). The Reface circuit is similar to the S910 circuit.
Here are the MIDI signals at the Reface DIN-6 pins:
Pin 1: MIDI IN, Ground via decoupling capacitor
Pin 2: MIDI OUT, Ground
Pin 3: MIDI IN, LED cathode (-)
Pin 4: MIDI OUT, TX serial data
Pin 5: MIDI IN, LED anode (+)
Pin 6: MIDI OUT, pull-up to 3.3V
Please note the DIN-6 pin numbering, position and connector orientation!
Now, let’s match up the Reface DIN-6 pins to regular MIDI DIN-5 pins. The MIDI IN match ups are:
MIDI IN MIDI IN
Reface DIN-6 MIDI DIN-5 Function
------------ ------------ -------------
Pin 1 No connection
Pin 1 Pin 2 Ground via decoupling capacitor
Pin 3 No connection
Pin 5 Pin 4 LED anode (+)
Pin 3 Pin 5 LED cathode (-)
I put the MIDI DIN-5 pin numbers in ascending order. The MIDI OUT match ups are:
MIDI OUT MIDI OUT
Reface DIN-6 MIDI DIN-5 Function
------------ ------------ -------------
Pin 1 No connection
Pin 2 Pin 2 Ground
Pin 3 No connection
Pin 6 Pin 4 Pull-up to 3.3V
Pin 4 Pin 5 TX serial data
At this point, I suggest grabbing your Reface MIDI adapter cable and tracing the DIN-6 to DIN-5 connections with a continuity checker. This is the best way to come to grips with the real-world connections and signal/pin positions.
A rainy New England day and the leaves and pine needles are piling up. Can’t do much of anything outdoors today, so off to GC. (Not that I really want to do yard work.)
No real agenda. I’ve been thinking about Yamaha Montage vs. Tyros 5++ vs. Nord Stage 2 ex vs. Electro 5d. That’s all “long term” as I’m having a lot of fun and staying busy with the S950 and MOX.
I really could use a “lap piano” for rehearsals. (A distant relative of “floor melodica?”) My body ached so much last Wednesday before rehearsal that even an eight pound Korg Triton Taktile was too much to schlep. So, I sang with the group, hoping to internalize the melodies of the new music for the week. This isn’t such a bad idea in any case, since it’s good form to sing along in one’s head while playing — improvisationally or not. A good reminder that, yes, hymns actually have words.
So, the issue of mini-keys rises from the grave like Joan Crawford. About one month ago, I sought and found a Yamaha Reface to try again. As it seems for most interesting music tech, one needs to drive a zillion miles or take two or more trains to find and play Reface, Montage, Korg Arp Odyssey and so forth. And thus it was to play a Reface DX. I had a fair chance to plink away and the DX provided a wide range of solid sounds. But, still, no love for the Reface mini-keys. I simply cannot imagine playing a Reface at rehearsals and even remotely enjoying the experience.
Today’s journey was inspired by a favorable review of the new Korg MicroKorg S in Sound On Sound magazine. What a pretty picture it is; Korg’s industrial design may ape Arturia, but they took the best! The review mentioned the larger mini-keys (what an oxymoron!) of the Microkorg XL+ and I decided to find a comparably equipped Korg.
Happily, today’s trial was the Minilogue, which proved to be a fun time indeed. It’s got a pretty sweet sound for an inexpensive polyphonic analog synth. With the right programming, I could even warp the Minilogue into a “lap piano” good enough for rehearsals. A built-in speaker a la the new Microkorg S would be nice. However, I could easily run it into the JBL Charge 2 that serves as the battery-powered amplifier for the Triton Taktile 49 (my usual rehearsal ax). It’s a shame that the Minilogue isn’t battery powered, too, as it would make a terrific portable instrument.
The Minilogue’s oscilloscope is a real treat and is totally entertaining. It’s also a reminder that I need to add a mini-/micro-oscilloscope to the dining room lab one of these days. The oscilloscope display is a small OLED screen much like the screen in the Triton Taktile.
The Minilogue’s keys are far more playable than the Reface. The keys are longer than typical mini-keys and the black keys (sharps and flats) are narrow. This combination makes for a surprisingly effective keyboard design. I wouldn’t want to play a gig with these, but they are suitable for plinking out melodies and such at rehearsal. (See this article at Synthtopia for a good analysis of the Minilogue’s key size.) Several other Korgs have the same key design: the Korg Arp Odyssey and the “Natural Touch” microKEY, to name two.
I’ll say this for Korg. They may miss the mark sometimes, but these folks are actively innovating at a fast pace!
After messing with the Minilogue, I revisited the Nord Stage 2 ex. This is a fine instrument and is in the same premium range as the Yamaha Montage. Having also revisited the Montage in recent weeks, the Nord’s string and woodwind voices just don’t come up to the same level as Montage. The Montage voices live and breath. Although the Nord is quite good, these voices sound like “sample playback.” Kudos to Yamaha.
I will have more to say about Montage in a forthcoming post. In short, is it time to spring for Montage or wait for the successor to the Tyros 5 (“Tyros++”)?
With so much to do and learn, it’s been a long while since I’ve taken a peek below the hood of an electronic musical instrument.
Yamaha caught the world by surprise with its Reface series of portable keyboards. So far, there are four models in the series: Reface YC (organ), Reface CP (electric piano), Reface CS (analog modeling synthesizer), and Reface DX (4-op FM synthesizer).
Before I get to the DX and CS, here’s a few thoughts about the YC and CP. According to Yamaha specifications, the Reface YC tone generation engine is “AWM (Organ Flutes)”. This suggests to me that the YC uses a standard AWM tone generation integrated circuit (IC) like the SWP70. Hammond-like “Organ Flutes” have been part of the mid- and upper-tier arranger workstations like Tyros for a very long time. Thus, I suspect that the YC implementation is an updated implementation of the arranger technology.
The Reface CP tone generation engine is specified as “SCM + AWM2”. SCM or “Spectral Component Modeling” is the modeling technique first employed in the flagship CP-1 stage piano. SCM and AWM2 are also used in the CP-4 and CP-40 models. The CP-1 uses three tried-and-true SWP51L tone generation ICs: master, slave and effects. The master and slave generate the base piano tones and the two ICs share the same WAVE ROM. Total WAVE ROM size is 1024Mbits or 128MBytes (organized as 16-bit words) which is a ridiculously small amount of memory for a top quality piano. Such is the power of SCM!
The CP-1’s samples are stored in two Lapis Semiconductor MR26V51252R devices (32M by 16-bit words each). The processor is a Yamaha SWX02 (SH-2A CPU core operating at 135.4752MHz). There’s not much to the CP-1 user interface, so a relatively light-weight, low-cost processor is enough for the job. The SWP51Ls handle all of the heavy computation.
Thus, the Reface YC and Reface CP are relatively uninteresting from a technologist’s point of view. The YC and CP use proven technology from other Yamaha products. That leaves the Reface CS and Reface DX.
Although the CS and DX implement two different tone generation techniques — analog physical modeling vs. frequency modulation (FM) — they are fraternal twins at the hardware level. They share much of the same base hardware design with a few variations to handle their unique user interface requirements.
The CS and DX both use a Fujitsu MB9AF141LAPMC1 processor to handle key and panel scanning. Here’s a quick summary of its characteristics:
CPU Cortex-M3
CPU Frequency 40MHz
On-chip flash memory Main area 64KBytes
On-chip flash memory Work area 32KBytes
On-chip SRAM SRAM0 8KBytes
On-chip SRAM SRAM1 8KBytes
Peripheral interfaces:
DMAC 8 channel
Serial I/F 8 channel
Base timer 8 channel
Dual timer 1
Realtime clock 1
Watch counter 1
12-bit A/D 12 channel
This processor is a good choice for embedded control applications where low power and low cost are important. To my knowledge, this is the first product line using an ARM embedded microcontroller.
The Reface CS and Reface DX both use the proprietary Yamaha SSP2 (uPD800500F1-011-KN9-A) for tone generation. The SSP2 is Yamaha’s designated hitter for DSP tasks and is incorporated into many products. The SSP2 has an SH-2A CPU core operating at an internal clock speed of 135.4752MHz. The SSP2 has its own ADC, GPIO, UART, USB and serial audio interfaces. The SSP2 UART handles 5-pin MIDI communications. The SSP2 USB interface handles external USB communications.
The SSP2 has two memory interfaces:
DSP RAM: Connecting to 8MBytes of DSP SDRAM.
CPU bus: Connecting to 8MBytes of program ROM and 16MBytes of SDRAM.
Memory sizes and devices are the same in both products.
The AUX IN and audio out hardware design is also the same across the two products:
PCM1803ADBR ADC: AUX IN analog-to-digital converstion
AK4396: Digital-to-analog conversion for OUTPUT L/R and PHONES OUT
YDA176 D-Amp: DAC and amplification for internal speakers
This shouldn’t be any surprise. All of the Reface series products ahare the same external jack, power and key switch boards.
Digital audio is transfered serially between the SSP2, the ADC, the DAC and the digital amplifier. The SSP2 generates the master clock (MCLK) and bit clock (BCLK) to synchronize data transfers. MCLK and BCLK are derived from the SSP2 clock, in case you’re wondering about those odd-looking CPU clock frequencies. MCLK is 256*fs and BCLK is 64*fs, where fs is the sampling frequency, 44.1KHz. MCLK operates the AK4396’s digital interpolation filter and delta signal modulator. Data format is I2S and is probably 24-bit as it is in workstation products.
Aside from the other front panel controls, the Reface DX has two major additions: Capacitive sensors for the front panel touch strips and the LCD panel display. The printed circuit board positions for the LCD interface are not populated (i.e., no mount) in the Reface CS as it has no LCD display.
There you have it — two more examples of solid and conservative Yamaha hardware design.
Now, you may find the SSP2 to be incredibly boring. It is, however, a good choice for a low-cost, compact product. The Reface CS and DX need a metal shield over the SSP2, perhaps to control RF emissions, perhaps to radiate heat, or maybe both purposes together. Low power is a vital concern throughout the Reface series due to battery power concerns.
I’m a little hesitant to draw any inferences about future products. The Yamaha Montage supports 128 note, 8 operator FM polyphony. The Reface DX provides a relatively meager 8 note, 4 operator FM polyphony. Thus, there must be considerable hardware resources at work in the Montage. Well-worth the price, one hopes! And speaking of hopes, many people would like an analog modeling extension to the Montage. That would depend, of course, on the availability of spare computational horsepower.
