MIDI Hardware - MIDI.org Forum

USB Midi Host adapter

John Munro — Wed, 04 Mar 2026 18:16:05 +0000

I wish to setup 2 keyboards in a master/slave configuration. Neither keyboard has midi connectors. If I connect a USB Midi host adapter to each of the usb ports on the keyboards and then run a midi cable from midi out on the master to midi in on the slave will I be able to then send midi from the master to the slave.
Tks
John

Testing Web MIDI Latency on Android 6.0+ – Observations from VND88 MIDI Lab (2026 Build)

88 VND — Sat, 28 Feb 2026 02:12:30 +0000

I’ve been running a series of mobile Web MIDI latency tests using an internal experimental build referred to as the removed link " target="_blank" rel="noopener">VND88 MIDI Lab (2026 build). The goal is to benchmark event processing stability and controller response behavior across mid-range Android and iOS devices.

This is not a commercial release, but rather a controlled environment used to simulate multi-channel MIDI routing and real-time interaction.

Test Environment

Android

Android 6.0 – 13
2GB–6GB RAM devices
USB-MIDI via OTG
Chrome (latest stable)

iOS

iOS 12+
CoreMIDI compatible devices
Safari (latest)

Web

Web MIDI API enabled
PWA mode with offline cache

Observed Performance Metrics

Under standard conditions:

Event processing latency: 8–14ms (USB-MIDI direct input)
UI rendering: Stable 60FPS on mid-range devices
Multi-channel routing: No noticeable jitter under 4-channel simulation
Session encryption: AES-256 handshake (for preset sync validation testing)

Latency variance appears to increase when background processes are active, especially on Android 6–8 devices.

Installation Context (Test Build)

Android test build (~75MB APK):

Signed package (SHA-256 checksum verified)
Requires network + storage permissions
USB device authorization required at runtime

iOS deployment:

Distributed via TestFlight
CoreMIDI authorization on first launch

Web fallback:

Progressive Web App mode
Add-to-home-screen supported
Offline event logging enabled

Interesting Findings

Web MIDI performance on Android 6–8 shows greater timing drift compared to Android 10+.
Chrome seems to manage buffer scheduling more consistently than some Chromium-based alternatives.
USB permission reinitialization sometimes reduces latency spikes after extended idle time.

Open Questions for the Community

Has anyone benchmarked Web MIDI API latency across older Android devices?
Are there recommended buffer strategies to reduce 10–15ms fluctuation?
Any known limitations of OTG MIDI handling on low-RAM devices?
Best practices for stabilizing event timing in PWA environments?

I’m particularly interested in real-world field testing beyond lab measurements.

Appreciate any insight or shared benchmark data.

Testers for a powerful App that controls Windows with MIDI devices

Jamie Crowther — Fri, 30 Jan 2026 23:08:16 +0000

I’m looking for a small number of Windows users to participate in a private test of MIDI Command Studio — a desktop utility that turns MIDI controllers into configurable control surfaces for Windows applications.

The app maps MIDI notes, CCs, and faders to keyboard shortcuts, macros, and app/system volume, with per-device presets and LED feedback.

I’m inviting 5–10 experienced users with MIDI hardware to help validate the install, device handling, and core workflow before a wider release. Testers will receive a free license for the full version.

It's already quite a powerful tool for people who want to control windows with their MIDI devices.

If you’re interested, please reply or DM with:
– Windows version
– MIDI controller(s)
– Typical use case (e.g. editing, streaming, productivity etc)

New Behringer K2 MKII Needs Keystep with Hz/V an S-Trig

Bruce — Mon, 22 Sep 2025 23:16:46 +0000

Hi. It has been a while since I have posted anything here. I may not have posted anything at all. I have a question with my new Behringer K2 MKII and the Keystep 32. When I use the Arturia MIDI Control Centre and change the standard from V/Oct to Hz/V and R-Trig to S-Trig, and run a MIDI cable to the K2, it all works as expected. When I use V/Oct and R-Trig on the Keystep, it does not work as expected. However, when I look at the MIDI signals there seems to be no change in the data. I am not using the CV out and Gate out for anything. I am curious as to how this works.

I know there are things you can do to make the K2 respond to V/Oct and R-Trig but I would also like to be able to convert the information on my own using something like miRack and VCV Rack - editing MIDI signals as needed.

Roland SCXX vs Yamaha MU15 BEST?

mark — Tue, 03 Jun 2025 17:54:13 +0000

Im using a MU15 and a 2x2 midi sport for my 1 man band. Im looking to bau a backup sound generator in case of MU15 death.

Does a Roland SCxx sound better than the MU15? I love the sound of my wifes Roland E66 piano!

MIDI Powered-Unpowered Devices

Jaroslaw — Mon, 05 May 2025 21:35:33 +0000

I was disappointed with MIDI devices recently. I tried to connect my laptop and MIDI Solutions Quadra Thru V2 via Emu XMIDI 1x1 USB/MIDI adapter and the my other 4 synths. Quadra Thru is a brilliant idea on which this device is built. It needs only 5v which MIDI system is based on.But Emu adapter doesn’t provide such voltage. It doesn’t provide any voltage or just 0.0002v. I haven’t been aware that passive and active MIDI devices exist. MIDI is MIDI and connected devices should work. But they don’t… How could the renowned company, Emu, build such a poor device? I have got two of them. Fortunately, I own M-Audio adapter which provides 5v.

Roland SD-35 MIDI Player Replacement?

Mike C — Tue, 18 Mar 2025 22:22:42 +0000

Does anyone know of a satisfactory replacement for the Roland SD-35 MIDI player (pictured below)? I'm on my 4th unit. As they are out of production, I'm looking for a replacement. Any suggestions for a hardware general MIDI player that is easy to use on the gig? (not looking for a laptop solution) Thank you.

removed link " />

Digital Flex Accordion

Андрей Боровой — Wed, 05 Feb 2025 23:22:17 +0000

Где можно заказать , приобрести Digital Flex Accordion ?

More than one CC-message per USB-poll?

Oor Tone — Wed, 05 Feb 2025 14:40:52 +0000

If I understand correctly the polling rate on USB-midi communication is usually 1 kHz.

If a USB-midi device is sending CC-data over USB, let's say a knob is turned swiftly, quicker then the polling rate, then will all CC:s in the same poll be considered arriving at the same time in the USB-host (usually a computer), or are they timestamped so their relative positions are kept, or are all but the last CC per poll conisdered relevant?

Multiple CC messages at the same instant seems pointless in almost all situations as opposed to simultaneous Note-Ons which makes sense. But how is this handled by the protocols?

The question can be reversed. If a DAW has higher timing resolution than the poll rate (Logic as an example has twice the resolution @120 bpm) how is this timing handled when sent out to a USB midi-device?

Midi goblin arpeggiator and patch librarian videos

andrew crawford — Mon, 27 Jan 2025 19:15:32 +0000

Hi there, Im the creator of MIDI Goblin. It's an open source, esp32 powered 5 pin midi device that does a whole bunch of things. I posted about it here a while back but I've since made a few improvements. I also made a couple new youtube videos that go into detail on how to use it as a hardware patch librarian and how to use it as an arpeggiator for synths with no internal arpeggiator (as well as midi controllers)

heres the video detailing using it as a patch librarian

removed link " target="_blank" rel="noopener">Patch Librarian tutorial - youtube

and heres the video that shows how to use it as an arpeggiator

removed link " target="_blank" rel="noopener">Arpeggiator tutorial - youtube

It does a whole lot of other things too, here are the current little "apps" it can run

hardware patch librarian for user defined devices (midi controllers and synths and even synths with only midi input like volca keys)
patch morpher
arpeggiator for received notes (works with synths and midi controllers)
scale generator (very basic right now)
chord generator (very basic right now)
midi cc lfo
32 step sequencer
cc remapper (primative but it works)
midi controller (for cc parameters, nrpn is in the works)
monitor for received midi messages (works with nrpn, cc and note messages)

It also has a few other features as well.

all the apps can run at the same time
arpeggiator can be synced to the sequencer (scale generator is planned to as well)
it can use its internal clock or midi clock messages to control the speed of the sequencer or arpeggiator
it can send program change messages
3 user defined buttons that can toggle apps on/off, load patches, load sequences or send panic messages
all the user defined button actions can also be triggered by up to 99 received midi cc messages
the output midi channel for each "app" can be set individually
settings for all apps, triggers, midi channels, user buttons are unique to each synth users add
files are saved to a removable micro sd card
theres a wizard for adding devices like synths and midi controllers
it comes with multiple synths pre-installed

Also its open source. You can get the firmware removed link " target="_blank" rel="noopener">here and the schematics are available removed link " target="_blank" rel="noopener">here, theres also some available IO on the pcb that could allow tinkerers to add their own mods if they want. Though it's definitely a lot easier to just pre-order one through removed link " target="_blank" rel="noopener">backerkit.com with the info available on removed link " target="_blank" rel="noopener">midigoblin.com you could make your own goblin for sure.
MIDI Goblin is a one-man project right now, but I ran a kickstarter for it last year and am currently shipping orders, I'm am pretty happy with how things are going (though I definitely ended up loosing money on the kickstarter campaign (d'oh!))