Frequently Asked Questions
Powering the MIDI Solutions Products
MIDI Solutions products don't have power inputs – do they require batteries?
MIDI Solutions products are powered through the MIDI connection – no batteries or wall adapters are required to operate with most products! Please read the FAQs below for exceptions.
Can the MIDI Solutions products be powered from any MIDI connection?
MIDI Solutions products draw power from either a MIDI Out or MIDI Thru connected to their MIDI input (MIDI Solutions products with multiple inputs draw power from their first MIDI input, In1). MIDI Solutions products were originally designed to be compatible with the 5V MIDI electrical specification, however the MIDI specification has recently been updated allowing a lower voltage of 3.3V, so devices that follow the new specification will not power the original MIDI Solutions products (see this FAQ). We are currently working on MultiVoltage versions of the MIDI Solutions products that are compatible with both the original 5V and new 3.3V MIDI specifications. These MultiVoltage products resolve most compatibility issues, however we have received reports of a small number of products on the market that do not provide the ground connection to the center pin as indicated in the MIDI specification (this FAQ provides more details).
Why not add a power jack to all of the MIDI Solutions products that could be used only if needed?
Unfortunately connecting a power source to a MIDI-powered product will create a ground loop (see this FAQ). To eliminate ground loops all MIDI inputs would need to contain optical isolation circuitry. However, optically isolated MIDI inputs cannot draw power, and without any MIDI inputs that can draw power, a wall adapter would no longer be optional, but required for every MIDI Solutions product. Rather than require the use of a wall adapter for every MIDI Solutions product, we decided to offer the Power Adapter as a workaround for those cases in which power is not available.
Ignoring ground loop issues, is it possible to connect a power source in parallel with the MIDI source that is connected to a MIDI Solutions product?
In theory this could work with the addition of level translation circuitry. For example if the MIDI source is operating at 3.3V, and a 5V power source is connected in parallel, then the incoming 0 – 3.3V data signal would need to be translated to a 0 – 5V signal in order to be recognized by the MIDI Solutions product. It's possible this could even work without level translation circuitry if the positive data source voltage exceeds the positive input threshold voltage. But even if it appears to work it may not be reliable since there is the potential for the threshold voltage to shift out of range in response to temperature changes. The MIDI Solutions Power Adapter both resolves the level translation problem and eliminates ground loops.
Is it possible to use a MIDI Solutions product as a stand-alone device without any devices connected to its MIDI input?
MIDI Solutions products are powered from the device connected to their MIDI input, so even if they don't need to receive MIDI messages they must still be connected to a MIDI Out or Thru to receive power (most MIDI Solutions products offer an echo parameter which can be programmed to OFF to prevent MIDI messages from passing through the product). If no free MIDI Out or Thru ports are available to provide power to the MIDI Solutions product, a MIDI Solutions Power Adapter can be used to provide power. Or, if you don't mind dabbling in electronics a bit you can connect an external +5V DC power source to the MIDI input of the MIDI Solutions product as follows: Connect the ground of the power source to the center pin of the MIDI input jack (pin 2), and connect +5V of the power source to the two pins on either side of the center pin (pins 4 and 5). The outermost pins may be left disconnected. MIDI Solutions products will operate down to about 3.5V, so three 1.5V batteries supplying 4.5V could also be used instead of a 5V power supply. Or a 5V USB power source could be used as described in this article. Please be sure to double-check the voltage and connections; MIDI Solutions will not be responsible for products that have been damaged by incorrect interpretation of the above instructions. Note that this workaround applies only to applications for which nothing else is connected to the MIDI input of the MIDI Solutions product.
What are the benefits of the MIDI Solutions MultiVoltage products over the original MIDI Solutions products?
The original MIDI Solutions products are unable to draw power from devices that have been designed with the new 3.3V MIDI electrical specification. MIDI Solutions MultiVoltage products are compatible with both the original 5V and new 3.3V MIDI specifications.
While the number of original MIDI Solutions products that could be powered from a single MIDI Out or Thru was previously limited to four, it is now possible to power up to 10 MIDI Solutions MultiVoltage products from a single MIDI source. The exact number will depend on the specifications of the MIDI port that is supplying power, please continue reading for more details.
MIDI Solutions MultiVoltage products also offer some new diagnostic tools. If the operating voltage of a MIDI Solutions MultiVoltage product drops below the threshold at which it is able to provide the standard MIDI drive current of 5 mA, its LED will produce a steady on/off warning flash. After rising above this threshold the LED will continue to produce a steady on/dim flash for 10 seconds. Since the voltage always rises above this threshold on power up, a steady on/dim flash will always be visible for 10 seconds on power up (during this time the unit is operating normally and providing the standard drive current). By observing this diagnostic it can be determined if the number of MIDI Solutions products that are chained together will operate reliably; if an increase in activity such as sending Pitch Bend or Continuous Control Change data for a few seconds causes the voltage to dip below this threshold the LED will produce a steady on/dim flash for 10 seconds, indicating there are too many products chained together to provide the standard drive current under these conditions. Most MIDI inputs will still receive data reliably at reduced drive currents, however for critical applications in this case it is recommended that the number of MIDI Solutions products in the chain be reduced, or a MIDI Solutions Power Adapter be inserted at the beginning of the chain.
If the operating voltage of a MIDI Solutions MultiVoltage product is below 4V its LED will produce a dim flash every four seconds, this signal is for diagnostic purposes and does not affect its operation. This diagnostic can be used to determine if the device that is providing power to the MIDI Solutions product is using the original 5V MIDI specification or the new 3.3V MIDI specification. It is recommended that just a single MIDI cable be connected from the device to the MIDI Solutions product when observing this diagnostic since connecting additional products will draw down the operating voltage relative to the device that is providing power.
Since some products make use of unused pins 1 and 3 to pass phantom power, connections to these pins are now provided between selected jacks (see the operating instructions for specific product details). These pins are not connected to the MIDI Solutions products' internal circuitry. It is recommended that the current passing though these pins be limited to 1 amp.
Programming the MIDI Solutions Products
How do I set up the products for the function I need if they don't have any buttons or switches on them?
MIDI Solutions products are programmed by sending them MIDI System Exclusive messages from a computer with a MIDI interface. The computer and MIDI interface is only required to program the products, once the MIDI Solutions products have been programmed they retain their settings and can be inserted wherever required in your MIDI setup. The Roland UM-ONE, Roland UM-ONE mk2, and Yamaha UX16 are low cost USB MIDI interfaces that can be used for this purpose. Avoid the MIDI interfaces on this list which have been reported not to provide power to the MIDI Solutions products. Also be cautious of bargain MIDI interfaces which may be unable to send complete MIDI System Exclusive messages. If you are unsure if your MIDI interface is sending the complete programming messages then connect a MIDI cable from your MIDI interface's MIDI output directly back to its MIDI input, and view the MIDI data in SendSX for Windows, or MIDI Monitor for the Mac.
The MIDI Solutions Programming Tools software makes the programming process easy. The software creates the System Exclusive programming commands automatically as settings are selected from drop-down menus. The software is available free for download, even if you haven't yet purchased a MIDI Solutions product. It's quick to install and easy to navigate, and spending a few minutes with it is an excellent way to familiarize yourself with the MIDI Solutions products. The Programming Tools software is available for Windows and Macintosh.
We don't offer a version of the Programming Tools software for Linux, but this program allows programming commands to be entered manually and transmitted to the MIDI Solutions products. A disclaimer however that this program was suggested by one of our customers and we have not tested it here.
Is it necessary to program the MIDI Solutions products each time they are powered up?
MIDI Solutions products retain their settings even after they are powered down, so programming only needs to be done only once to initialize them, or to change the settings.
Functionality of the MIDI Solutions Products
Is it possible to chain multiple MIDI Solutions products together for more functionality?
MIDI Solutions products can be chained together in a modular fashion to provide exactly the functionality that is needed. Up to four MIDI Solutions products (except for the MIDI Solutions T8) can be powered from a single MIDI Out or Thru, and even more of the new MultiVoltage products (see this FAQ for more information). In applications where even more products need to be chained together the MIDI Solutions Power Adapter can power up to 20 MIDI Solutions products.
Do MIDI Solutions products introduce any noticeable delay?
MIDI Solutions Processors use fast processing algorithms to ensure that received data is processed and transmitted byte by byte whenever possible. This means that transmission of outgoing data bytes is started even before all bytes of an incoming MIDI message have been received, resulting in very small latencies. The MIDI Solutions Thru boxes and Power Adapter process MIDI data bit by bit, resulting in even smaller latencies.
There are only two circumstances in which MIDI data can be delayed longer. The first is when MIDI messages arrive at both inputs of a merger at exactly the same moment, one of the messages must be buffered to allow the other to pass through (this of course is a limitation of MIDI, not of the merger). The second is if an outgoing result depends on the value of the following byte. For example, if a MIDI Solutions product is programmed to filter all messages above a specific value then the third byte of the message (which specifies the value) must be received before the MIDI Solutions product can determine whether or not the message should be transmitted, adding 0.64 ms to the delay. These additional delays of milliseconds or fractions of milliseconds result in latencies that are still extremely small, much smaller than is possible to hear. The default settings for the programmable MIDI Solutions products are to pass all MIDI data unchanged allowing MIDI messages to be sent byte by byte, with a typical delay of 0.5 ms. By comparison it is estimated that the shortest time difference distinguishable by humans is approximately 10 ms, so even with up to 20 MIDI Solutions products chained in series the delay should not be noticeable. To put it in perspective the typical delay is equivalent to the time it takes sound to travel approximately six inches through air, so more delay is introduced by leaning forward or backward while playing than by inserting a MIDI Solutions product inline in the MIDI data stream.
Will inserting MIDI Solutions products in my setup cause ground loops?
According to the MIDI specification, every MIDI connection must be optically isolated in order to avoid ground loops. Without optical isolation, a MIDI cable can create a ground loop by making an additional connection between devices that are already grounded together via a wall outlet. In order to obtain power from a MIDI Out or Thru, MIDI Solutions products do not contain an optoisolator at their MIDI inputs, however neither are they connected to a wall outlet for power, so no ground loop is created thus far. Subsequently the MIDI output of the MIDI Solutions product is connected to a MIDI input that does contain an optoisolator, so a ground loop is never created between any two devices by inserting a MIDI Solutions product inline. A MIDI Solutions product is essentially just an extension of the circuitry of the sending MIDI device it is connected to. MIDI Solutions products with more than a single MIDI input, i.e. MIDI Solutions Mergers, do have optoisolators at the additional inputs, again preventing the possibility of ground loops.
Since the MIDI Solutions products act as an extension of the circuitry of the sending device, when sending longer distances it is best to use a short cable from the sending device to the MIDI input of the MIDI Solutions product, and a long cable from the MIDI Solutions product to the receiving device containing an optocoupled input (rather than a long cable from the sending device to the MIDI input of the MIDI Solutions product, and a short cable from the MIDI Solutions product to the receiving device). When making connections to the MIDI Solutions mergers, the shortest cable should go to the first input, and the longer cables to the other optocoupled inputs.
Do any of the MIDI Solutions products filter active sensing messages?
We have found that the problems introduced by active sensing outweigh its benefits, therefore all MIDI Solutions products (except Thru boxes and the Power Adapter) filter active sensing messages.
Do the MIDI Solutions products use running status when sending MIDI messages?
Yes, running status allows the number of bytes to be reduced by up to 50% when large amounts of MIDI data are transmitted, so it is used whenever possible. This is especially important when merging MIDI data as it can reduce latency when buffering of incoming data is necessary. The status byte is included with the outgoing message after brief periods of inactivity to ensure the receiving device is updated regularly with the current status. The MIDI specification states that a receiving device must always recognize running status.
Although very rare, we have received reports of a few devices that do not recognize running status, and requests from customers for a product that forces the status byte to be sent with each MIDI message. We do not make a product that does this, however using the MIDI Solutions Event Processor it is possible to insert an extra MIDI event after specific incoming MIDI events in order to force the status byte to be sent with each message. For example, a channel pressure event of value zero could be inserted after each Note-on and each Note-off event changing the status to channel pressure, causing the status byte to be resent with each note.
The following products have been reported NOT to recognize running status:
Axxess Electronics GRX4
Electronic Theatre Controls Express 24/48, Expression 2X
RJM Music Mini Effects Gizmo
Roger Linn Designs AdrenaLinn
I have an older MIDI Solutions product, is there a way to find out if it includes a particular function?
Since we are constantly adding new features to the MIDI Solutions products, older units may not include all of the functions described on our website. To find out if the product you own has a particular function implemented send an email to firstname.lastname@example.org and we'll help you determine this.
I have a unique MIDI processing requirement that is not offered by any of your existing products. Do you do any custom work?
Yes, we can make firmware modifications to our existing products (no hardware modifications). For more information see the Custom Products page.
Troubleshooting the MIDI Solutions Products
Why does the MIDI indicator LED not light up even though the device that is connected to the MIDI Solutions product is powered on?
First of all, check the connections to confirm it is a MIDI Out or MIDI Thru that is connected to the MIDI input of the MIDI Solutions product (not a MIDI In to MIDI In, or MIDI Out or MIDI Out). If the LED still does not light, then check that the MIDI cable you are using has all three of the centermost pins connected at each end; on rare occasions we've seen MIDI cables that do not connect the center pin, and although these cables will work with devices that are not MIDI-powered they do not allow the MIDI Solutions products to draw power. It's best not to use these cables anyway as this ground connection is intended as a telescoping shield to protect the MIDI data from outside interference. If the problem still isn't resolved try connecting the MIDI Solutions product to a different MIDI device; the MIDI electrical specification has recently been updated allowing a lower voltage of 3.3V, however the MIDI Solutions products were designed to be compatible with the original 5V specification, so devices that follow the new specification will not power the MIDI Solutions products. We are currently working on MultiVoltage versions of the MIDI Solutions products that are compatible with both the original 5V MIDI specification and the new 3.3V MIDI specification. These MultiVoltage products resolve most compatibility issues however we have received reports of a small number of products on the market that do not provide the ground connection to the center pin as indicated in the MIDI specification (this FAQ provides more details).
If the device that you need to connect to the MIDI Solutions product does not provide power one workaround is to first connect to another MIDI device, and then MIDI Thru from that device into the MIDI Solutions product. If no other MIDI devices are available to make these connections the MIDI Solutions Power Adapter can also resolve the problem. The Power Adapter has a MIDI In, MIDI Thru, and a power connection for a wall adapter (included), and can provide power to the MIDI Solutions products by inserting it inline between the sending device and the MIDI Solutions product.
The following products have been reported NOT to provide power to the MIDI Solutions products (products in blue have also been reported NOT to provide power to the MIDI Solutions MultiVoltage products):
Aardvark DirectPro 24/96
Akai MAX49, MPC500, MPD24, MPD226, MPK series keyboards, MPX8, XR20
Alesis DM10, ControlPad, Micron, PercPad, Q and QX series keyboards, SamplePad, SR18, Trigger|iO, USB-MIDI Cable, VI25, VI49, Vortex
Artisan Micro-MIDI Controller Board
Arturia BeatStep, MiniBrute SE, MatrixBrute
Basyn MIDI Controller
Boss FC-50, GT-5, GT-8, GT-10, GT-100, GT-Pro, RC-50, RC-300
Cadac A,E,F,J-Type Consoles
Classic Organ Works MIDIjetPro
Clavia Nord C1, C2, C2D, Electro 3, 4D, 4HP, 5D, Lead 4, Modular G2, G2X, Piano 2, Stage, Stage 2, Stage EX
CME U2MIDI, U-Key, WIDI-X8
Cyclone Analogic TT-303
Dave Smith Instruments Mono Evolver Keyboard, Mopho x4, Poly Evolver, Prophet '06, '08, Rev2, Tempest, Tetra
Digidesign 003 Factory and Rack, Command|8
Digitech GNX4, GSP1101, VHM5
E-MU 0404 USB 2.0, Xboard 49 and 61, Xmidi 1x1, Xmidi 2x2
Echo Audiofire 2/8/12, Layla3G
Edirol UM-1 and UM-2 USB MIDI Interfaces, UA-25
Elektron Machinedrum MK1, Monomachine MK1
ENGL Special Edition E670
ESI MIDIMATE II
Faderfox DJ2, DX2, LD2, LX2
Focusrite Clarett, Saffire, Scarlett
Fractal Audio Systems Axe-Fx Ultra
General Music pk5
G-Lab GSC, GSC-2, GSC-3
Hammond SK1, SK2, XK-1, XK-1c
High End Systems MIDI/LTC Widget
iConnectivity iConnectMIDI1, iConnectMIDI2+, iConnectMIDI4+, mio
IK Multimedia iRig
Ion KEY 49
Korg KP3, SP-250, Triton Le, earlier models of the Triton Studio, X50
Kurzweil MIDIBoard, PC3LE, PC3X, SP4-7, SP4-8, SP5-8
Line6 MIDI Mobilizer
M-Audio Axiom Pro 61, Code 49, Fast Track C600, Keystation 61 and 61es, Midisport 1x1, 2x2, 4x4 USB MIDI Interfaces, Oxygen 25, ProKeys Sono 88, Radium
Master Gaita Master Gaita
Miditech Midiface 4x4
Moog Little Phatty, MP-201, Taurus 3 Bass Pedals
Musictech Music Maker
Native Instruments Komplete Audio 6, Maschine MK2, Traktor Audio 10
Nord (see Clavia Nord)
Novation Impulse keyboards, nio 2/4
One Control CrocEye
Orla Ringway RS600EU
Radikal Technologies Spectralis 2
Resident Audio T4
Rock Band 3 Wireless Keyboard Controller
Rocktron MIDI Raider
Roland A-37, AX-7 (older models), FR-3, FR-18, GR-20, HD-1, JV-90, PC Series keyboards, PK-5 (PK-5A does provide power), TD-4, TM-2, V-Piano, VG-99
RME Babyface, Fireface 800, HDSP 9632
Samson Carbon 49 and 61
Source Audio Soleman
Starr Labs AirPower
Steinberg Midex 8, UR242
Strymon BigSky, Mobius, Timeline
Studio Electronics Boomstar
Studiologic MP-113, MP-117, Numa Nano, Numa Nero, Numa Organ, TMK 88
Tascam 2488neo, DP-01, DP-02CF, US-122
TC Electronic Flashback X4, G-System
TC-Helicon VoiceLive Rack
Technics SX-F100, SX-FA1, SX-G100, SX-GA1, SX-GA3
Use Audio Plugiator
Voce MIDI Drawbar, V3
Yamaha 01X, AW2400, EZ-TP, GT1, GT2, i-MX1, KX8, KX61, MOX8, MOXF8, MX49, MX61, NP-30, NP-31, P Series keyboards, PSR275, PSR-S950, PSR-S970, Tyros5-76, WX7
Please send an email to email@example.com if you discover any other products that should be added to this list.
Is it possible to modify the above devices to enable them to provide power to MIDI Solutions products?
If a device won't provide power to an original (non-MultiVoltage) MIDI Solutions product because the device is using the new 3.3V MIDI specification then no simple modification can be made to resolve the problem, inserting a Power Adapter or switching to a MIDI Solutions MultiVoltage product is the only solution. The device's MIDI output voltage can be measured between the center pin (ground) and the pin next to it in the counterclockwise direction.
If a device won't provide power to a MIDI Solutions MultiVoltage product then this is likely due to the omission of the connection from pin 2 (the center pin) of the device's MIDI output to ground as indicated in the MIDI specification. Pin 2 of a MIDI cable is connected to its shield, so even if the device will not be powering a MIDI Solutions product it is important that pin 2 is connected to ground so that the other conductors in the cable that are transmitting MIDI data are shielded from outside interference. This problem can be repaired by making a ground connection from another ground point on the device to pin 2 of its MIDI output. In some cases a ground connection can be found on the shield of an external jack, so opening up the product to find an internal ground connection may not be necessary and this external ground can be tied directly to the MIDI Solutions product's ground. The ground connection of the MIDI Solutions products is available at pin 2 of any of its MIDI jacks (with the exception of merger inputs 2 and higher). When making this connection be absolutely sure that the point on the device you are connecting from is ground – MIDI Solutions will not be responsible for products that have been damaged by incorrect interpretation of the above instructions, attempting this modification is not recommended for those unfamiliar with electronics. It would also be wise to first do a continuity test between the device's ground connection and pin 2 of the device's MIDI output to confirm that this is in fact the problem and this connection is missing.
My MIDI Solutions product is operating intermittently, what could be wrong?
Of course we would never rule out the possibility that a MIDI Solutions product could be defective, but it is a very rare occurrence. One thing that we have found to be very common however is bad MIDI cables. Usually it is an individual connection within a MIDI cable that fails – if the connection to pin 2 of a MIDI cable fails the MIDI cable will still work with other MIDI devices, but the MIDI Solutions product will not be able to draw power. If a connection is just starting to weaken the MIDI Solutions product may power on occasionally, while bending the cable may cause it to connect and reconnect, resulting in the MIDI Solutions product turning on and off. Check to see if bending the cable (usually close to one of the ends) with the MIDI Solutions product connected causes the LED to turn on and off. Note that it takes a few seconds for the LED to turn off when power is removed from a MIDI Solutions product, so try holding the cable in different positions rather than bending it back and forth quickly.
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