Alesis Vortex – First Review: What’s inside? (Tear Down)

I received an Alesis Vortex today:

Of course, I will do a user review.  I also did a functional review. But first, a tear-down!

(As usual, a click on the picture will enlarge it) I will try to be precise when describing the placement of parts: the Vortex is seen in this picture as a spectator would see it, but the user (musician) will see it in reverse, and upside down! So I will refer to the photos as you see them when pointing left and right (and up and down).

First impressions

The Vortex weighs about 2.5 Kilos (5.5 pounds). Shiny white plastic all around (that will probably hold a nice paint job pretty well). Construction is tight and nothing is rattling. The size is just right. The keyboard is 3 octaves. There are numerous buttons, knobs and switches that I’ll cover in this tear-down. They feel kind of mushy, but it’s the build underneath that will determine their  lifespan.

Opening the Vortex

Very starightforward. 15 small screws (all the same) hold the front and back together. Once removed, you just have to slide the front under the keyboard and flip it on it’s back (pretty obvious when you try it). No hidden screws. Standard cross pattern. Be careful not to break any of the cables! You will have to unplug three of them.

As you can see, there is not too much in there. The designers could have made the whole thing a lot smaller, but I feel that the size is just right and making it smaller would have made usage less comfortable. One BIG advantage is that this design leaves a LOT of room for expansion/hacking! It will be very easy to add switches, sensors, LEDs and whatnots in there. Lots of projects for the future. I already a plans for the first hack: I will add a remote Midi sender in there this week end!

So, from the top left, clockwise: The Left Hand board, that has all the switches that are activated by the players … left hand. A single cable goes down to the Main board, hosting the Arm Cortex micro-computer and logic parts. Just to the right, adjacent to the Main board is the Pad board. The small board at the extreme right is the Connection board. At the bottom is the actual Keyboard. Now in detail…

The Main Board

The Main board is quite simple. From the left: 3 digits (blue) and some logic chip (74HC374 Flip Flops). The 5 lozenges are soft switches (with a LED in the middle(blue)). Contact is made when the resistive material on the board is shorted by the resistive material under the soft rubber pads. The advantage is silence and resistance to wear (and dust).

You can clearly see the micro-controller: an Arm Cortex STM32F103 RBT6. This particular chip runs at 72 Mhz and contains all sorts of interface pins, like USB, Digital and Analog inputs and outputs and Serial Port (for Midi communication). An ideal chip for a flexible, sensor driven instrument.

To the right, a few more chips take care of the interface logic with the other boards.

One interesting bit is actually under the main board: The accelerometer:

It’s glued to a little block of styrofoam. Looking at the board itself, I think that the accelerometer was initially glued or soldered to the board. But it is now raised about 1 cm, and attached to the board with a short cable. I did not decipher the part number, but it looks like a generic accelerometer.

The Pad Board

The pads are on the right side of the Vortex (from the musician’s point of view).

The front of this board (where the pads are) is made of the same resistive material as the switches shown on the main board. They also have a blue LED in the centre. The reverse side of this board is interesting: There are two piezo sensors attached (glued) to the back. They are used to simulate a drum pad action for the switches on the front. It’s the first time that I see this design for a drum pad. Usually, a multi segmented resistive trace is all that’s used (like my Korg Nano Pad). The more traces that make contact, the higher the value sent to the processor. In the Vortex, although the traces are segmented, it’s the piezo sensors that determine the apparent velocity of the press. One advantage: if you hold a pad switch down and tap the Vortex (enough to make the piezo react), a control value will be sent after the original signal.

The Left Hand board

The board support the left hand sensors: A scaled touch sensor and a pitch bend wheel. There is also a sliding potentiometer and a bunch of switches. The pitch bend wheel has a nice feel. Some instruments have wimpy wheels and others have springs that are way too strong. This one is good and offers just the right amount of resistance. The sliding pot is cheap and the action is quite short.

The other side of the board is more interesting. Again, it is covered with resistive traces for the soft switches. The touch sensor is in the middle. It is quite sensitive and has a nice “slip”. By that I mean that the surface of the sensor (some kind of plastic) is not extremely smooth: just enough of a texture to let a (sticky) finger slide while providing a little feedback. There is a small potentiometer above the touch sensor. It is used to adjust the sensitivity of one of the sensors (or the zero-at-center of the pitch bend wheel).

The KeyBoard

The keyboard is versatile. It has velocity measurement when a key is pressed, AND velocity measurement when the key is released. So a quick release will send a higher value out the Midi port. The picture below shows the end of the Aftertouch sensor. It is placed under the keys and is activated when the user presses hard enough on the key, at the end of its travel. If you press too hard (which is easy), the value is stuck at 127. The difference between just-enough-pressure-to-activate the Aftertouch and enough-to-staturate it is minimal. This will require some practice.

In the picture above, you can barely see the little rubber cap that protects the switch and velocity sensor under each key. Nice design: dust proof.

They keys are cheap lightweight plastic. I find them too light, but they have a feel very similar to my M-Audio Oxygen 49, and many other cheap keyboars. My old Casio keyboard feels like a real piano, but it weighs more than 25 kilos (55 pounds)!

The Connection Board

The last board is the where the Vortex connects to the outside world: Midi Out, USB (2.0), Power In (5 volts)(power supply not included) and a Sustain Pedal jack (6.3 mm-1/4 inch). Finally, there is a switch to select power source: Off, Battery or USB/5V jack Powered. Yes, the Vortex can be powered by 4 AA batteries. You will need that to connect through the Midi port by itself. The current draw on the batteries is 30 mA when idling and climbs to about 40 mA max. So a set of AA batteries will last, theoretically, about 80 hours. Rechargeable will be a good choice here, although they will last less than alkaline, so carry a spare.

I have connected it to an iPad (3) with the camera connection dongle, without batteries, and it works fine. But the Vortex draws more power than the iPad is supposed to allow. Maybe the circuit reports less than it actually consumes (dirty trick). My iPhone 5 refuses to recognize the device, batteries or not. I guess it would be just fine using the iRig Midi or equivalent with the Midi connector. I can’t test that.


Overall, I like the construction and design. The vortex is solid enough for my use: light gigging and studio work. The build quality could be better: a few connections were a bit loose and some tape (to hold wires in place) were not holding anything. Nothing major, but Quality Assurance should have taken care of that.

37 keys might seem a bit limited, but keep in mind that the Vortex is made to let you use your right hand on those keys. It requires quite a bit  of contortion to get the left hand on the keyboard! The left hand is control-oriented, and there are plenty of controls just under your fingers. For two-handed operation, I will definitely use the M-Audio Oxygen or the old Casio keyboards.

The vortex has enough flexibility with multiple switches of different formats (little round ones, big square ones, huge (pad) ones and a few in between) placed all over. Everything is programmable and presets can be stored in the device.

I love the empty space inside the Vortex! Plenty of room for new switches and sensors. I will add a Midi Wireless Remote before the next post.

An internal Wifi would have been awesome. That can be hacked in though. So can a rechargeable battery. And a more sensitive accelerometer. And a better display…


26 responses to “Alesis Vortex – First Review: What’s inside? (Tear Down)”

  1. Alex Avatar

    This was very useful to me. Great teardown. Can’t wait for the user review. I also can’t wait to see what you’ll do with hacks, especially the wireless midi. Cheers!

  2. Godly Avatar

    I’m thinking of revamping my Vortex.
    So your pictures come in very handy. Is it really hard to disassemble it? Or even more, to reassemble it? LOL

    1. Very easy! Just a few (well… 16!) standard screws and you can separate the two halves. Then removing the internal components is easy too.

  3. Hugh Blemings Avatar
    Hugh Blemings

    A great post, thanks for taking the time to write things up!

    I’m curious if based on what you’ve seen, if it would be possible to move the keys such that the keyoard started with an E instead – move highest key (presently a C) to the lowest position then swap the CDE block with FGAB if that makes sense ?


    1. That’s a strange modification! I think that it could be done. But each key is shaped differently in an octave. So except for the last one, which you noted is shaped uniquely, not being adjacent to a black key, each key would have to be unscrewed and moved to its new position. I will have to verify is the contact switches need to be move too. I will in a few days.
      Wouldn’t it be just simpler to just transpose the outgoing Midi commands to generate the proper shift? You can use the “Keyboard Zones” buttons to assign a transposition to the keys. See my programming guide.

  4. Alejandro Bena Avatar
    Alejandro Bena

    Thanks for the data!!! Can I reverse the orientation of pitch wheel changin the order of potentiometer’s pins?

    1. I would think that reversing the two external pins on the pot would reverse the pitch wheel action. Just cut and solder a pair of jumper wires. The pitch wheel is unfortunately not programmable.
      Why not use the Ribbon for pitch? It is programmable and it’s action can be reversed.
      Also, you could use a simple software like pizmidi from to do it on a computer. Or use a micro-controller to do it!

      1. Robert Avatar

        Just out! Alesis has published a patch editor on their web site. It incluse a new firmware for the Vortex. One of the new functions is the ability to reverse the pitch Wheel direction! This will definitely solve your problem.

        There will be a full review by the end of the week.


  5. Hey,
    Nice! Saved me from having to take apart just to plan things out.
    I was wondering if you think it would be easy to swap all the leds and screen for red, and also what components would I need and where I could find them. Thanks!

    1. Changing all the LEDs would be quite an undertaking… there are many different sizes and some would be very difficult to un-solder and replace. Find another project… it’ll be more fun!

  6. Alex Avatar

    Got my Vortex all patched to work with the OpenMusicLabs MIDIvamp1 synthesizer. Next step, going to hardwire the MIDIvamp1 into the Vortex to turn it into a synthesizer keytar! Wish me luck!

  7. Madolyn Avatar

    I believe I blew the circuit on my board by accidentally plugging it into too high of a voltage cable. Any suggestions on how to fix this? Is there a removable fuse that can be replaced, or can the entire connection board be replaced?

    1. There is no replaceable fuse in the Vortex. You might be able to identify the blown part and replace it, but this requires knowledge in electronics. I think that the solution will be to contact Alesis and replace the board. Hopefully, only the power supply board is burnt (most likely the voltage regulator)!


    I am about to get a Vortex Wireless, and was going to tear it down immediately after purchase, but this already confirms the good a priori impression about the components and the upgrading potential.
    One thing that I’d add almost immediately is a 50-cm ribbon controller running along the whole keyboard (like what the Korg RK-100S has). Since the volume control slider is clearly a simple potentiometer (and is assignable), I can hook up the ribbon as either an alternative to the slider (with a physical switch for changing between the two), or maybe hook them up in parallel (or whichever is the right way to do this), so that the original slider affects the range/resolution of the long ribbon. Of course there would be no latching, and probably no way to play notes just by touching the ribbon (like on the RK-100S), but I think in combination with the adjacent keyboard and the sustain button it will be quite usable for divebombs, long-range slides and such – more usable than, say, the accelerometer.
    And of course more controls near the left hand would be nice – either touch sensors and an Arduino like in your modification, or some more potentiometers. Like for the long ribbon controller, the poor man’s hack would be to relocate or duplicate the original 3 knobs on the left side of the keyboard (just right of the “neck”). If the original knobs are plain potentiometers, it just could work, with no need for additional MIDI encoding devices.

    If anyone is still reading this, are there suggestions for a sound module small enough to fit in the casing? polyphony would be a plus, but a monophonic synth-bass sound would already be OK. Though I admit it’s a bit crazy to make the Vortex into a synth.

    1. Hello Serguei,

      It’s a good idea to add that ribbon. It could replace the volume controller, or the small “ribbon” itself. The volume control is an easy fix, but you will have to try and find a ribbon controller that has a similar resistance. Easy enough to measure.

      The original knobs are very standard potentiometers. Easy fix too.

      For a sound module, have you looked at the Raspberry Pi? A few people have developed synths for it and it could probably fit somewhere in the Vortex. Although I would probably just stick it ON the Vortex, with some lights… hummmmm… giving me ideas here! The RaspPi can power the Vortex with one of its USB port. The only thing is that the RaspPi needs quite a bit of power. Heavy battery here. This thing needs 1 amp!
      The Raspberry Pi also has a Bluetooth connection, so you could even use it to send the sound to a remote bluetooth receiver/speaker!

      1. SERGUEI MECHKOV Avatar

        Hi Robert, (it is Robert, right?)

        Although a full-time programmer, I think I’ll stay off the Arduino and Raspberry Pi bandwagon for a little while longer. At least for the Vortex, I think I’ll just settle for a MidiTech Pianobox Mini (a.k.a. MidiPlus Mini Engine), which has a decent set of GM sounds (decent except for the harpsichord, which is awful as usual, and a bunch of other so-so samples). What sold me on the Pianobox (Mini) is that its battery (2100 mAh) can power the Vortex (or any controller) over USB and that it will take not only pitch bend, modulation and volume, but a bunch of other CC messages that can shape the sound in real time (maybe not for all the patches, but for some it’s clearly the case as demonstrated here: ). Also, some of the patches actually sound multitimbral (will check when I get it), and the polyphony is OK too. Not sure how bad the built-in reverb is, but with a guitar FX pedal (or a KaossPad stuck to the Vortex along with the Pianobox), this does sound like a solution suitable for live use, not just headphone practice.

        1. I didn’t know about the MidiTech products. Sounds great! They are very expensive (on this side of the Atlantic) though.
          As you can see in this blog, for me, the fun IS in the hacking part… so I’ll work on a DIY midi mini sound box. I have to prepare some class material on the Raspberry Pi (I’m a teacher) anyway.
          Let us know how the MidiTech Pianobox is doing in real like!


          1. SERGUEI MECHKOV Avatar

            I am getting the Pianobox tomorrow and the Vortex later on. I am totally planning to do some hacking – with the long ribbon controller, the duplicated or relocated knobs, and some slots for the Pianobox and maybe a Kaosspad (and why not an iPad/iPhone dock as well). But the Arduino or Pi is sort of the next step – I’ll come to that in a year or so, if further needs arise.

            So far I’ve completed only one MIDI project, that is a rather nice-looking 2-octave pedalpoard (for an organist friend), with the Behringer FCB1010 on top of it for program changing and volume control – and I almost attempted an Arduino hack of the FCB1010 (to customize what its buttons did), but then found a modded ROM (chip) that just plugged into the board and solved the problem. Same thing here – first I looked up the MidiVamp1 from one of the posts up there, found that it and other ready-to-play minisynths were no longer sold, then considered plugging in an analog Meeblip Anode or Triode (monophonic, but awesome) or a Shrhuti 1 or preenFM2 (great, but expensive), or an Alesis Nanosynth (almost too heavy and large for installation on or inside the Vortex). But, now that I found the Pianobox (first the big one, then the Mini, which I am getting for 60€ used), it’s as if the Vortex was already synth-capable, in a plug-and-play sort of way. The other thing is that the Pianobox can stay outside the Vortex (although I’ll try and make them dock together neatly), and can be used on the road (or, for the more decent sounds, on stage) with any other MIDI keyboard or drumming controller. That’s huge versatility, for practicing and other wireless needs. One could, for example, grab an old Korg RK-100 (there’s one in Paris for 250€) which has a wooden body without as much room for internal hacking as the Vortex, and make it into a decent synth-capable keytar nonetheless.

            That said, if I ever get to the point where I add controllers to the Vortex rather than relocate or duplicate existing ones, I will still have to get an Arduino or some dedicated encoder/merger that would patch into the MIDI signal sent out by the Vortex. But if I do that, I’d want to go all the way and support MIDI over USB (class compliant?), and that sounds like a completely different level.

            Sorry for the endless rambling, I hope I’m not tiring anyone.

          2. Don’t worry…. you’re not boring me!
            In the last paragraph, you talk about MIDI over USB. Have you looked at the teensy micro-controller from ? That’s what I used when I modified my Vortex to add touch sensors. It merges the Midi coming out of the Vortex and the Midi commands generated from the touch sensors. This project is described here:

            If I can find a cheap Pianobox I might buy it. I’m curious. But for most of my synth sounds, I use my MacBook and Ableton Live (and GarageBand…). It’s less portable but still usable live.

          3. SERGUEI MECHKOV Avatar

            I confirm that the Pianobox (or Mini Engine if you get it from MidiPlus rather than MidiTech) is not just a plain GM sound bank but a GM-based synth, even though it’s not documented anywhere (the leaflet that you get with it just has a list of 127 patch names, but nothing like a MIDI implementation chart).
            Apart from the volume, pitch bend, modulation (sounds like tremolo) and reverb, there’s stuff like attack, decay, release, chorus, resonance, cutoff, sustain, sostenuto, soft pedal, portamento (on/off switch and speed), vibrato (amplitude and speed), stereo pan, switch between polyphonic and lead sound, and some kind of soft “second attack” that you can engage (repeatedly if you want) while the sound is sustaining.

            Haven’t yet experimented with drums or multitimbral sounds (like GM Echoes or Calliope). Maybe those have extra parameters. But the drum sounds are there (on channel 10), also not documented 🙂

            Some of those are noisy or otherwise low-res, but definitely usable (I’m particularly happy about the support of filter resonance/cutoff and portamento/monophonic). And the rechargeable battery lasts quite a while (I’ve had it plugged in for hours now, although it’s not powering the controller that I’m using to probe it). Come to think of it, some of the noise I am hearing now may be due to low batteries.

  9. Mike Homan Avatar
    Mike Homan

    I have the newer wireless version and just use the wireless dongle in my iPhone and/or iPad and I am really happy with some of the apps. Korg M1, MusicStudio and igrand. Plus I can read my texts in between songs.

  10. MocciJ Avatar

    It’s been several years now since I’ve bought the Vortex, wired version. The pitch wheel minimum was not zero but 5-6: I fixed that by better aligning the potentiometer above the touch strip. The pitch wheel is directly bolted into such potentiometer, the latter had its pins slightly bent, so I added some padding between it and the ribbon to keep it aligned.
    The only reason I might upgrade the Vortex to the newer ones is the wireless. However, the Vortex wireless version seems identical to the wired one, except for the color and the additional usb dongle. Has someone disassembled it? Is there a new wireless chip that we can install? There are reports of people flashing the wired firmware version on their Vortex wireless by mistake, and the only thing they lost was in fact the wireless communication. I’d be glad to just buy the USB dongle and solder a component instead of buying a new Vortex.

  11. Hey Robert,

    Maybe you can help me with your opinion if you’re still reading this here..

    I put Vortex together with Novation Launch Control, so, that it’s very simple and I’ve got all what I need as I’m more of a musician and less of a geek (all respect to geeks, but I’m not there unfortunately) So, I did the silly thing of putting the 2 instruments together while covering some screws and generally loosing the ability to open Vortex fully. I know.. I know.. a silly idea. But I had my Novation LaunchKey66 for 4 years, had been throwing it on the floor and loosing buttons and generally mistreating it, but never had to open it up to repair anything as it’s brilliantly well made and solid.
    Now with the Vortex something else happened. I’ve been treating is very nicely but the USB input cable started becoming more and more glitchy till it stopped working completely! So, at first the Vortex simply made my Ableton and Logic go crazy with the USB input loosing and getting back the signal. Now the keytar can be turned on by the ON button (to use with batteries), so I know that it is working as such and that it shows values changing when the buttons/keys are played, but the USB cable is not sending any signal to the computer. When plugging in to the computer the Vortex doesn’t even light up, basically the socket must be dead completely. Now I tried turning it ON to work with the batteries and plugged in through the MIDI socket. My computer kind of was showing some sort of a new input but wasn’t playing my MIDI notes in Logic or Ableton. I’m not sure if this socket is working properly, I have never used it!
    The usual USB plug was working perfectly till it became glitchy and died..
    Now the question is: what do you think the issue could be? Do you think the USB socket inside has come off the board for plugs? Would a simple soldering sort it out? Do you think I should get a new socket? I mean.. I’ll have to somehow cut it open very carefully to not destroy it completely!
    Another thing. If I want to be serious about using this instrument, I should have 2 of them, right?

    Any suggestions are super welcome!
    You can have a look at how I made these two instruments into one:

    Thank you for any bit of your time at all!! Big hugs,


    1. Hey Indra,

      You’re quite the hacker! I’m impressed by the transformation of your vortex! Thanks for sharing the video.

      I think it’s the USB socket that desoldered itself from the little board where the power switch, the midi plug and the USB plug are. You can’t buy that piece separately, I think. But if you find someone with a broken Vortex, you could recuperate one. I had some trouble with mine and it was just a loose soldering joint. It could be that for you too. Do you know how to use a soldering Iron?

      Also, you mentioned that you tried using the MIDI socket. Since you’re using a Mac (logic is Mac only), you will need to configure both Ableton and Logic to use internal midi ports. What is your MIDI cable plugged into? (Yes, I know, the Vortex… but the other end?) Try GarageBand. It will be easier to test the MIDI connection than using the other two programs, although, since you were using MIDI through USB, you should be able to configure the programs already.

      Keep me posted. If you lived around here, I could fix it for you. But yo could send me the little board and I could fix it, if nothing else works.

      1. Hi Robert!

        I managed to fix it! Gosh.. It really was a mission to cut into it (as mine was a bit “glued” together 😉
        As soon as we opened the keytar end we realised that the USB IN socket looks a bit larger or somehow weird! The socket looked extended. So, we pushed back the extended wall of the socket to where it originally had to be and the keytar started working! I’ve learned my lesson now and will know that the USB socket is quite different to a jack lead input and really doesn’t need much strength to plug it in! Which is what I think had caused this problem. (+crap parts or design)
        Now I’m about to create another one of these to make sure I have 2 instruments!
        Thank you so much for the photos of the insides! I could not have managed to cut open safely my crazy creation without your pics!
        I am in London UK! If you are anywhere in Europe, then it would be lovely to invite you to a gig! In any case: thanks for all your help! Hugs, Indra

  12. Very well-written tear down.

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