Yamaha PSS-A50 top and bottom [Click images to enlarge]
The A50 has two main boards: the digital and analog electronics board (DM) and the front panel board (PN). After removing nine screws — don’t forget the screw hidden in the battery compartment — the A50 splays into two halves: the bottom half containing the battery compartment, DM board and keybed, and the upper half containing the speaker and PN board. The battery connects to a JST XH connector on the DM board. Ribbon cables connect the keybed and the panel board to the DM board.
Yamaha PSS-A50 front panel board (PN)
The PN board has traces for the front panel buttons. The buttons are arranged into a 3 by 8 switch matrix: 3 drive lines and 8 sense lines. The power Standby/ON switch has two dedicated lines. The eight sense lines are shared with the three digit LED display. A further 3 lines are devoted to the display (for a total of eight lines). In addition to the front panel switch matrix, the PN board conducts audio signals to the speaker through two wide PCB traces.
I dare to say that the A50, PSS-E30 Remie and PSS-F30 have the same panel board. Only the front panel graphics and software differentiate the models in that regard.
Yamaha PSS-A50 main electronics board (DM)
The DM electronics board is tiny and is packed with surface mount (SMT) components. Impressive! The main digital components are:
Yamaha YMW830-V: Processor and tone generator (IC101)
Winbond 25Q16JVS1M: 16Mbit Serial flash memory (IC102)
74VHC273: 8-bit latch for display data (IC301)
NXP LPC11U13F/201: USB interface (IC401)
The YMW830-V is also known as “SWLL” and is a Yamaha proprietary system on a chip (SOC). The A50 has separate amplifiers for the speaker (IC701) and headphone output (IC601):
TI TPA6132A2RTER: Headphone amplifier (IC601)
Rohm BD27400GUL: Mono class-D power amplifier (IC701)
NJR NJM2740M: Dual operational amplifier (IC501)
The dual operational amplifier is part of the post-DAC low pass filter. Finally, the power-related components are:
TI TLV74333PDBVR: 3.3V regulator (IC001)
TI TPS63060DSCR: Switching regulator (IC004)
TI TPS25200DRVR: 5V eFuse/power switch (IC006)
The A50 must choose and switch between +5V USB power and battery power. That’s the role of the eFuse/power switch component.
Yamaha PSS-A50 USB interface (NXP ARM MCU)
The NXP LPC11U13F is a bit of a surprise to me. It is an ARM Cortex-M0 32-bit microprocessor (MCU) with 24KB of flash memory. The SWLL sends and receives MIDI through its UART RX/TX ports. The ARM LPC converts simple MIDI from the SWLL to MIDI over USB. Using an ARM MCU to do the job seems like over-kill. It goes to show how far we have come as an industry when an MCU can be dedicated to such a mundane task!
Yamaha PSS-A50 CPU (Yamaha YMW830-V SWLL)
The SWLL (YMW830-V) has many of the specs that we’ve come to know about Yamaha’s entry-level CPUs. The external crystal resonates at 16.9344MHz. The SWLL internal clock is 33.8688MHz and generates a 67.7376MHz master clock. If these numbers look odd to you, simply note that they are even multiples of 44,100Hz, the basic sample rate:
67.7376MHz = 44,100Hz * 1,536
When an external DAC is used, the master clock provides the bit serial audio clock. 1,536 can be subdivided in all sorts of interesting ways depending upon sample word length.
The SWLL integrates host CPU, memory, tone generation, serial MIDI communication, keyboard and front panel scan ports, and display ports. The digital to analog converter (DAC) is also integrated into the SWLL. The SWLL is truly Yamaha’s low-cost system on a chip solution.
The SWLL loads its software and samples from a 16Mbit serial flash ROM. 2MBytes for software and samples is not much, so one wonders if the SWLL has a preprogrammed flash memory of its own?
With the exception of the ARM LPC chip, the A50, PSS-E30 Remie and PSS-F30 electronics are identical. The software and samples determine the product personality. Such a high degree of commonality allows Yamaha to manufacture PSS keyboards (in India) and sell them at a dirt cheap price. Hats off — the amount of technology at this price — less than $100USD — is simply astounding.
Today’s topic — power — may seem rather mundane. To a modder, though, power gives our circuits life.
I’m going to make a few comments of general interest before diving into details that are relevant to the Yamaha PSS series keyboards, including the PSS-A50 and PSS-E30 Remie.
Most of us don’t think too much about keyboard power. Sure, we know where the AC adapter connects or how to insert batteries. The internal details are hidden from us.
However, did you really read the fine print in the Owner’s Manual? The front panel power button may be labelled “Standby/ON” instead of “OFF/ON”, and the difference is important. The PSS-A50 Owner’s Manual states, “Even when the Standby/On switch is in standby status (display is off), electricity is still flowing to the instrument at the minimum level.”
Yes, that Standby/ON switch is really a “soft” power switch. It does not physically disrupt the flow of electrical current from the AC adapter (battery or USB port). In the PSS series (and other keyboards, too), the Standby/ON switch sends a signal to the keyboard’s processor telling the software to change the current power state. For the technically inclined, the Standby/ON switch pulls one of the processor pins to ground and software detects the ACTIVE LOW signal.
The rest of the story gets complicated fast depending upon power saving techniques supported by the hardware. Let’s assume that we’re changing from ON to Standby. The processor generates a separate signal which switches off the power amplifier — a major drain on battery or external power. Software turns off the display, another power hog. Finally, software places the processor in a low-power state and waits for the Standby/ON switch to be pressed again. Going from Standby to ON, software turns everything back on.
From the user’s perspective, the transition from Standby to ON is fast. No waiting and let’s get playing! The constant low current flow does affect battery life, however. Ever wonder why the batteries drained sooner than expected even though you haven’t turned your keyboard on for a few weeks? The low current flow eventually drains the batteries.
Power management has implications for people intending to mod an instrument. I’m planning to add an audio delay or filter circuit to the A50. The add-on circuit will need to draw power. Ideally, I would like to switch the add-on circuit on and off with the front panel switch. But, where should I take power from the existing design? Is there a PCB pad or trace that is big enough for soldering? Is voltage regulated at that point? Getting power is not a no-brainer!
If you don’t have the instrument’s service manual and schematic, this analysis gets really hairy and uncertain. For the E30/A50, I’ve been working from the PSR-F50 manual available from Elektrotanya. The PSS series keyboards are a revamped PSR-F50 design.
I’m considering a Synthrotek Dev Delay for add-on. The Dev Delay has a 5V regulator and runs on battery power. My thought is to connect the Dev Delay directly to the A50’s batteries through its own power on/off switch. That way I don’t add to the standby drain on the batteries. It just means turning the delay on and off separately.
PSS-E30 Remie main board (battery connector at right)
Even better, the A50 main board (DM) has a removable battery connector. If I rustle up a compatible cable and connectors, I can tap into existing battery power without soldering. I was already planning to use a short 3.5mm patch cable to jump the headphone OUT to the Dev Delay IN. Again, no soldering to SMT traces, etc. I like “reversible” mods!
I had enough headaches and scars from soldering mod chips to game console boards back in the day. 🙂
I hope this discussion provided some useful advice — no matter what you mod.
As I mentioned in my PSS-A50 review, the Yamaha PSS-A50 arpeggios date back to the first Motif keyboard (2001). Yamaha — like most manufacturers — recycle content and these arpeggios (arps) have (re-)appeared in several synthesizer and arranger products. The arps even made an appearance in the now unavailable Yamaha Synth Arp and Drum Pad application for Apple iPad.
If you were fortunate enough to buy the Synth Arp and Drum Pad app ($8 USD), don’t throw that joint out the window! As of this writing, the old app still runs on iOS.
The A50 resembles a hardware embodiment of the old arp app. The A50, however, has one trick up its sleeve that the app didn’t have — Motion Effects.
The PSS-A50 Motion Effects add a little animation to performances, arps and playback. There are three kinds of Motion Effects:
Group A: Filter
Group B: Pitch
Group C: Modulation
The filter effects do things like filter sweeps. The pitch group includes pitch bends. The modulation group adds modulation and a little bit of everything else like slicing.
The A50 is an inexpensive little guy with simple synthesis hardware. All of the Motion Effects are implemented through MIDI, keeping hardware cost low. The Motion Effects themselves are based on the MIDI control arpeggios in the original Motif! This bit of recycling keeps development cost ultra-low.
Using a Motion Effect is easy. Select an effect, start playing, and press/hold the MOTION EFFECT button when you want to trigger the effect. The A50 then generates the MIDI needed to make the effect happen. Effects are selected by repeatedly pressing the MOTION EFFECT button while holding SHIFT. (Tip: Hold MOTION EFFECT in order to skip to the next effect group.)
Motion Effect MIDI messages are recorded and transmitted along with note ON/OFF and all the rest of the usual stuff. Thus, the A50 is a bit of an interesting controller as you could use it to add/record pitch bends, etc. to a DAW-based MIDI song or live performance.
Inquiring minds want to know, “How did they do that?” I recorded the MIDI messages produced by each of the Motion Effect types. I simply played a note on the keyboard and hit/held the MOTION EFFECT button. If you would like to hear the results for yourself, here is a ZIP file containing SMFs. Open the SMFs in a DAW and explore.
The filter group sends MIDI CC#74 (continuous control) messages. A09 and A10 toss in modulation (CC#1) for a little extra spice:
Since it’s often hard to describe sonic effects in words, here are miniature plots of the MIDI controller data for the filter (Group A) effects. [Click images to enlarge.]
Yamaha PSS-A50 Motion Effects (filter)
The pitch group sends MIDI pitch bend messages:
Group B PITCH B01 Pitch Whole-Note Up PB (wheel) B02 Pitch Half-Note Up PB (wheel) B03 Pitch Whole-Note Down PB (wheel) B04 Pitch Half-Note Down PB (wheel) B05 Choking Up PB (wheel) B06 Choking Down PB (wheel) B07 Pitch Down 1 PB (wheel) B08 Pitch Down 2 PB (wheel) B09 Pitch Up 1 PB (wheel) B10 Pitch Up 2 PB (wheel) B11 Pitch Up + Modulation PB (wheel), CC#1 B12 Pitch Up 3 PB (wheel)
The first several pitch effects implement guitar-like bends. If you have trouble bending notes with a joystick or wheel, you might want to try the A50. You get a perfect bend every time — maybe too perfect. The plots below illustrate the PSS-A50 pitch (group B) effects.
Yamaha PSS-A50 Motion Effects (pitch bend)
The modulation group has some real variety to it. The simple modulation messages change pitch at a fixed rate; you cannot change the “LFO rate.”
Group C MODULATION C01 Modulation On 1 CC#1 C02 Modulation On 2 CC#1 C03 Pitch Up + Modulation On 1 PB, CC#1 C04 Pitch Up + Modulation On 2 PB, CC#1 C05 Expression Slice 1 CC#11 C06 Expression Slice 2 CC#11 C07 Expression Slice + Filter 1 CC#11, CC#74 C08 Expression Slice + Filter 2 CC#11, CC#74 C09 Pitch Up + Expression Slice 1 PB, CC#11, CC#74 C10 Pitch Up + Expression Slice 2 PB, CC#11, CC#74 C11 Pitch Up + Expression Slice 3 PB, CC#11 C12 Pitch Up + Expression Slice 4 PB, CC#11, CC#74
Slicing implements stutter-like effects using MIDI CC#11 expression messages (alternating volume ON and OFF). The plots below illustrate the modulation (group C) effects.
PSS-A50 Motion Effects (modulation)
Here’s a quick reference guide to the MIDI message types mentioned above:
PB Pitch Bend
CC#1 Modulation
CC#10 Pan (not supported by PSS-A50)
CC#11 Expression
CC#71 Harmonic Content (resonance)
CC#74 Brightness (cutoff)
If you would like more information about the Yamaha PSS-A50 MIDI implementation, check out the basics and advanced topics.
First, the bad news. The PSS-A50 does not have a way to save and restore recorded MIDI data. Thus, you can’t save a song and reload it later.
It is possible to SYNC a DAW (like Sonar) to the A50 and record MIDI data played back by the A50. I accomplished this task rather easily in Sonar. The A50 sends MIDI START, STOP and CLOCK. I simply configured Sonar to accept and sync to the A50. I armed the destination Sonar track, hit Sonar’s record button, and pressed the A50’s play button. Sonar recorded all incoming MIDI data to a single track. Sonar’s selective filtering made it easy to separate data in the track by channel.
Even if MIDI data is recorded to Sonar, there isn’t a way to play it back into the A50. The A50 does not recognize MIDI CLOCK, START or STOP.
Next, I tried MIDI bulk dump request messages. The A50 ignores them — no response. I also tried XG MIDI parameter request messages and they are ignored, too. I’m not too surprised because other entry-level arrangers ignore these kinds of messages, too. [The Yamaha SHS-500 Sonogenic is equally silent.]
In a moment of due diligence, I ran Musicsoft Downloader and it is unable to connect to the A50. Well, for $100, you can’t expect everything!
I experimented with reverb- and chorus-related messages. The A50 responds to MIDI CC#91 Reverb Level and CC#93 Chorus Level messages. However, you cannot change either the chorus or reverb type via standard XG parameter change messages. The chorus and reverb are pretty basic and I’m not really surprised.
In terms of quality, the chorus is just OK. The reverb sounds cheap when it is cranked up. As far as future mods are concerned, I’m inclined to beef up reverb and/or spatial enhancement. The Volca Mix’s enhancer made quite a difference in sound quality. Lacking stereo OUTs, the A50 sound doesn’t have much life by itself. (MIDI-wise, it doesn’t recognize CC#10 Pan.)
The PSS-A50 does respond to MIDI identity request:
F0H 7EH 0nH 06H 01H F7H
In case you’re wondering, identity request and reply are how external software can query and identify external MIDI devices. When the A50 is pinged with an identity request, it responds with:
F0 7E 7F 06 02 43 00 44 27 1F 00 00 00 7F F7 | | | | | | | | | Version | | Model | Family Yamaha
Hex 43 is Yamaha’s manufacturer/vendor code. Hex 44 identifies the device family: arrangers. Hex [27,1F] identifies the specific model within the device family.
I’m itching to examine the PSS-A50 motion effects. That’s the next stop.
To learn more about the Yamaha PSS-A50‘s MIDI implementation, I monitored its MIDI output stream using MIDI Ox and Sonar. Here are my notes. They are quite terse!
After inital start-up, the A50 sends MIDI timing clock and active sensing messages.
The default transmit data and channel settings are:
Assignment Ch# ---------------------- --- Live keyboard: 1 [If OFF, no data is transmitted] Live arpeggio sequence: 2 Recorded keyboard: 3 Recorded arpeggio seq: 4
Master volume is local. Pressing the Master Volume buttons does not send volume change messages (neither channel volume or MIDI master volume).
Changing Phrase Volume, however, sends channel volume on channel 3 and 4. Legends above keys show setting-related function: what setting, increment and decrement. This is very handy and avoids manual diving. Phrase Volume is changed using the assigned function keys.
Pressing a front panel voice button sends messages on both channel 1 and 2:
Bank MSB (CC#0) Bank LSB (CC#32) Program Change (PC) Channel Volume (CC#7) Reverb Depth (CC#91) Chorus Depth (CC#93)
Not all voices have chorus applied and Chorus Depth is not sent for voices without chorus.
The keyboard sends note ON and note OFF messages on channel 1. The mini-keyboard is touch sensitive. it’s difficult to send the full 1-127 velocity range with the default touch response level (level 2).
Pressing the Sustain button has the following behavior:
Sends new release time when sustain button is pressed.
Release time messages are sent on both channel 1 and channel 2.
Turning sustain off resets the release time.
Pressing Portamento (SHIFT+SUSTAIN), has the following behavior:
Sends portamento time and portamento ON/OFF when SHIFT+PORTAMENTO buttons are pressed.
Portamento time and ON/OFF are sent on both channel 1 and 2.
Turning portamento off, sends new portamento status on channels 1 and 2.
Pressing ARP ON doesn’t send MIDI messages! Pressing ARP OFF sends messages on channel 2:
Bank MSB (CC#0) Bank LSB (CC#32) Program Change (PC) Portamento Release Time (channel 1 and 2)
It’s like the A50 software assumes that the arp voice is set-up and ready to go when the arpeggiator is turned ON. Then, the software resets certain parameters when the arpeggiator is turned OFF. The arpeggiator sends note ON/OFF on channel 2 (as determined by the MIDI channel assignments).
Pressing PLAY sends the following messages on channel 1 and 2:
Start (FA) All Sound OFF (CC#120)
Pressing STOP sends the following messages:
Stop (FC) GM Reset (System exclusive) Messages to reset voice settings for channel 3 and 4
You can expect to see the following System Exclusive messages after song playback:
I’ve seen these XG MULTI-PART messages on other entry-level arrangers supporting the XG Lite conventions.
For Motion Effect A01 Filter 1, Pressing the Motion Effect button sends
these messages on channel 1 and 2:
Pitch Bend Sensitivity (RPN 0,0) Harmonic Content (CC#71) Pitch Bend Expression (CC#11) Modulation (CC#1) Brightness (CC#74)
Harmonic Content (filter resonance is increased to 100). The Brightness (cutoff) messages sweept the filter. Brightness is slowly modulated, i.e., it repeatedly slowly decreases and then increases.
Releasing the Motion Effect button sends messages on channel 1 and 2:
Pitch bend Harmonic Content (CC#71) Brightness (CC#74) Modulation (CC#1) Expression (CC#11) Pitch Bend Sensitivity (RPN 0,0)
These messages reset the respective parameters to a default value.
For Motion Effect B01 Pitch Whole-Note Up, pressing the Motion Effect button sends these messages on channel 1 and 2:
Pitch Bend Sensitivity Pitch Bend (center) Expression Modulation Pitch Bend (multiple messages)
The Pitch Bend messages sweept the pitch up then down. Releasing the button resets Modulation, etc. to default values.
Pitch bend sensitivity is sent as an RPN (Registered Parameter Number) message:
RPN (CC 0x64, CC 0x65) 0,0 Pitch Bend Sensitivity
The Motion Effect feature is similar to something I built into my two-button Arduino-based MIDI controller. It’s a way to add articulation to live playing. I always wanted a way to play perfect pitch bends. 🙂
I was able to save my recorded MIDI data to Sonar. The A50 insists on sending MIDI clock, START and STOP, so I configured Sonar to receive and respond to external clock. The recorded MIDI data is sent on channels 3 and 4. Thanks to Sonar’s channel selection feature (via event filtering), I could separate the channel 3 and 4 data into two tracks. Another possible solution is to write the data as a MIDI Type 0 SMF and then read the SMF into Sonar. Sonar should separate the channel data into different tracks.
Even though Summer NAMM 2021 is a live event, the global pandemic still has the business world topsy-turvy. The vaccinated parts of the United States are shaking off cob-webs, but large parts of the world remain in the grasp of COVID-19. Japan — a major source for electronic musical instruments — is in near crisis just as the Summer Olympics are due to start.
Thus, I don’t really expect much from Summer NAMM 2021. In the run-up to the show, vendors are mainly announcing product updates and upgrades. Manufacturers are highlighting previously announced instruments like the Korg Wavestate or Yamaha DGX-670 digital piano.
Truly new, is the Boss EV-1-WL wireless MIDI expression pedal. The price ain’t bad, $149USD, and it offers the chance to eliminate yet another cable in your live rig. Although it seems targeted for guitarists — being promoted through the Boss brand — the EV-1-WL might be a boon for keyboard players, too.
Boss EV-1-WL Wireless expression pedal
The EV-1-WL operates on two AA batteries or PSA-series power adapter. It cooks up MIDI three ways: Bluetooth, USB and 3.5mm TRS. Nice to have both wired and wireless options. According to Boss, all three can be used at the same time and are independently configured.
In addition to the rocking expression pedal, the EV-1-WL has a built-in top switch and two external footswitch inputs (1/4 inch TRS). Boss will provide an app to assign MIDI messages [quoting the Boss web page]:
Expression pedal with EXP SW on—CC# 1-31/64-95, value 0-127
Expression pedal with EXP SW off—CC# 1-31/64-95, value 0-127
Toe switch (EXP SW)—CC# 1-31/64-95, value 0-127
External footswitch 1 (CTL1)— CC# 1-31/64-95, value 0-127
External footswitch 2 (CTL2)— CC# 1-31/64-95, value 0-127
MIDI channel—1-16
Expression pedal curve—Normal, Slow1, Slow2, or Fast
EXP SW/CTL1/CTL2 mode—latch or momentary
I’m a little nervous about the EV-1-WL’s ability to rendezvous (pair) with any old Bluetooth device or interface adaptor. Boss state compatibility with their WM-1 5-pin adaptor and WM-1D USB-A dongle. However, will it interoperate with Yamaha’s MD-BT01, UD-BT01 or in-built Bluetooth MIDI (e.g., SHS-500 Sonogenic)? A 5-pin DIN MIDI cable is brand-agnostic.
The USB and Bluetooth MIDI world is rife with incompatibilities and the inability to make connection. A 5-pin MIDI cable is symmetric. A USB connection has a HOST end and a DEVICE end. Bluetooth has acceptors and initiators which must dance with each other when pairing. A MIDI cable simply connects an IN to OUT (and vice versa). Done.
Anyway, the EV-1-WL has got my attention and I look forward to the user manual and app. Hoping for the best…
The Yamaha PSS series keyboards are inexpensive, entry-level instruments which are super lightweight, battery powered, portable and fun. The PSS line is like a small group of fantasy characters where each character has its own super-powers.
PSS-E30: A musical game keyboard for younger kids.
PSS-F30: “Honey, I shrunk the arranger” keyboard for people who want to play songs with an accompaniment.
PSS-A50: A phrase-based music machine which records and speaks MIDI over USB to your DAW or other computer- or table-based music applications.
Last year, I reviewed the Yamaha PSS-E30 Remie and passed it along to our grandson as a Christmas gift. Remie is suitable for young kids, but even Mom and Dad have fun with the musical games.
Yamaha PSS-A50 keyboard [Click to enlarge]
The PSS-A50 (henceforth “A50”) is aimed at people who want more flexibility than the fixed accompaniment styles in the PSS-F30. The A50 has 138 musical phrases — “arpeggios” in Yamaha-speak — that drive an in-built arpeggiator. Twenty-two arpeggios are drum patterns; the rest of the arpeggios are melodic, covering both instrument-specific riffs (strums, bass lines, chord comps) and general purpose phrases like up/down broken chords, etc.
Experienced Yamaha players have seen these arpeggios before. In fact, the A50 reminds me of the Yamaha Synth Arp & Drum Pad iOS application. Without getting into the details, you select a voice, select an arpeggio (“arp”), enable the arp, hit record, and go. If you check out Yamaha’s YouTube tutorials, you’ll see how easy it is to get started.
At this point, I suggest watching Keen On Keys excellent video. It covers all the basics, a brief teardown, and more. I won’t go into such details here. (This chap did a terrific job!) I learned quite a lot from this video including basic “how to use it” information.
Oh, how I long for such reviews in Electronic Music (once Keyboard mag), once again. Ken Hughes, where are you? After reading one of those old product reviews, you actually knew a little about playing the instrument. Now, pfffft!
The sounds
Let’s get down to brass tacks. Like Remie, you won’t get Yamahas top sounds. Shucks, it’s only $100 USD (street price).
Truth be told, even though I regarded the A50 as a candidate for mod projects, I wasn’t too wild about the sounds that I heard in on-line demos. I was hesitant to buy one. Once I got the A50 under my fingers, however, I warmed up.
Basically, the A50 and Remie samples and synth engine are at the same level. The A50 adds touch sensitivity and that, I suspect, makes the difference. Sure, the piano (for example) is uni-dimensional and you can hear it play the same sample louder or softer depending upon strike velocity. The overall effect is more musical, however. Weird how that works?!
The A50 audio OUT is mono. Reverb seems to be the only system effect. Even Yamaha’s cheapest chip implementations have chorus, so it may take a little MIDI magic to unlock that door. The whole sound can be sweetened by out-board effects like maybe a guitar pedal (e.g., TC Electronic Hall of Fame reverb) or a spatializer. I slung an A50 beat through the Korg Volca Mix stereo width and compression effects and got a rather nice result. The Volca Mix Hi/Lo Cut let me isolate the tops and kick, too. I strongly recommend adding external effects.
The A50 motion effects let you juice up your performances. I’m still exploring the motion effects and I’m glad to have them. The motion effects add a way to vary the sound during performance, avoiding a uni-dimensional sound. You get filter fun, pitch bends, slicing and all sorts of sonic mayhem. A few effect types would be good for Hawaiian pedal steel. 🙂 It would be nice to leave the auto wah ON in order to play two-handed funk — a small quibble.
The A50 size, features and price invite comparison against the Yamaha SHS-300 and SHS-500 Sonogenic. Unless you really want the keytar format, I don’t see the value in the SHS-300 versus the A50. I will bet dollars to donuts that the SHS-300 is based on the same chip and samples as the A50. Personally, phrase recording is more fun and creative than a pretend, low-budget, cheap build keytar. Speaker quality is probably a wash between the two and the A50 puts out 1.5W versus 0.7W.
The A50 against the SHS-500 is another story. The SHS-500 voices are definitely better quality. Although the SHS-500 LINE OUT is mono, you can look to its PHONE OUT for stereo. The SHS-500 has PSR E-series DSP effects, three forms of MIDI (USB, 5-pin, and Bluetooth), a General MIDI sound set (available via MIDI only), and jam mode integration with Chord Tracker. The SHS-500 beats the A50 on sound. On the other hand, I prefer the A50’s speaker versus the SHS-500. Of course, the SHS-500 is mainly for playing and doesn’t have an arpeggiator or recorder.
Build quality
One big factor is build quality. The SHS-500 is a solid instrument. The SHS-300 and A50 are cheap. Even though Yamaha specs call out “37 HQ (High Quality) mini keys” for all three keyboards, only the SHS-500 is up to the same quality as the Yamaha Reface series. Yamaha marketing may claim otherwise, but you can feel the difference. The Reface and SHS-500 will stand up to abuse — the SHS-300 and A50, not so much.
As to A50 build quality, the electronic boards and cabling look up to snuff. EMI shielding is absent. Audio quality on battery power or external USB power adapter is good and is reasonably quiet. Powered by my HP desktop, the A50 is susceptible to digital schmutz and produces loud noise through its audio out. One could put blame on the desktop, but nearly all computer switching power supplies are dreadfully noisy. USB powered instruments need better filtering on USB power rails.
In use
I want to use the A50 as a looper: put down a rhythm line and a bass, then jam. It takes a little bit of practice to make glitch-free loops. I wish the A50 applied “measure quantize” to recordings, that is, trim recordings to a clean measure timing boundary. Right now, you have to turn off recording by feel and hope you get it right.
While horsing around with MIDI (another subject for another day), I noticed that the A50 has four parts, each on its own MIDI channel:
Keyboard voice: Live, real time performance (Default: channel 1)
Arpeggio sequence: Live, real time arpeggiation (Default: channel 2)
Recorded keyboard: Recorded keyboard performance (Default: channel 3)
Recorded arpeggio sequence: Recorded arpeggio (Default: channel 4)
Hmmm, this makes me wonder if I can layer up to four parts? So far, I can layer 3 distinct musical parts. The fourth part is still elusive.
The main problem is no overdub. It is possible to record two parts at once: arpeggio plus keyboard performance. Thus, you can lay down a drum pattern (arpeggio) and a bass line (by hand). Then, loop the playback and play over the top. Seems like I should be able to add a live arpeggio to the stack.
Play the bass line over the drum pattern. Start playing in time with the drum pattern.
Press REC to stop recording.
Turn the arpeggiator OFF.
Select a piano voice (e.g., voice 2).
Press SHIFT+PLAY to start a looping playback.
Jam over the playback.
Press STOP to stop playback.
Recording doesn’t start until you begin to play the bass line. That locks the bass to the drum pattern. You need to stop recording just before the next loop iteration begins.
If you need some jazzy chords, try: GM7/E, Fm7/B, FM7/D, Em7/A (also notated as Em9, Bm11, Dm9, Am11).
Doggone it, seems like I should be able to layer live arpeggiator into that mix! I’ll keep trying.
Update: Practice makes perfect. Yes, you can get four lines going. I recorded drum and electric piano following the procedure above. With the recorded parts playing, I started a looping bass arpeggio. Finally, I solo’d over the three running parts. Neat, and as complex as you might want for a little practice jam.
Questions
As I begin to explore the A50 MIDI implementation, there are a number of unanswered questions. First and foremost, can I save and restore recorded MIDI data? Does the A50 respond to SysEx messages for reverb and chorus type? Can I drive the A50 with the old Synth Arp and Drum Pad application and make use of its range of arpeggios? Can I load my own simple backing tracks into the A50’s recorder memory?
The final word
After my initial reluctance, I’m glad that I bought the PSS-A50. Apparently, some folks aren’t so happy as A50s turn up as Open Box items quite frequently. Even though $100 is not much, you can save a few extra bucks if you’re willing to buy an open box item. Given the build quality, you might not want to chance it, tho’.
The A50 does not have a full General MIDI sound set. The sound set is close enough for rock and roll, however. Here is an MP3 of the A50 in action (Traffic’s Feelin’ Alright). Wish I could play that piano solo at the end …
Interested in more PSS-A50 content? Check out these posts:
I’m happy to announce version 2 of my DJX-II styles for Yamaha Genos, Tyros and PSR arrangers.
These DJ styles are converted from the original Yamaha DJX-II patterns. If you would like to know more about the conversion process, please see: Mining the Yamaha DJX-II.
These are DJ styles, so they only respond to changes in the root note. The chord progressions are cooked into the patterns (just like intros and endings in regular PSR styles). I tried to find the best mapping from DJX-II patterns to style sections. Therefore, some of the DJXII styles have auto-fill, some do not. Longer “fill” patterns are assigned to the intro and ending sections which can play more than one measure.
Feel free to edit, rearrange and customize the styles in order to make them your own. I recommend Jørgen Sørensen’s excellent tools. Jørgen’s site also has documentation and tutorials about styles and style creation to help you along. Please check it out and support his work!
Version 2 includes all of the files in the first collection. Version 2 adds Drum ‘n’ Bass, Disco, House and Trip Hop styles. The ZIP file includes a README.TXT file which should help you get started with the styles. I have also included PDF notation files for people who read music and want to know about the chord progressions, bass lines, and so forth.
