3 Wireless MIDI Adapters offer 3ms & 0.38 ms latency

I would assume that a fair number of Zynthians are used in performance situations where the front man may have to be wireless. (A Zynthian user survey would be interesting)
Jordan Rudness big move
Jordam Rudess doing his big rock move : “The Kneel”

The greater power of a desktop or laptop system may be used in common studio situations. (It would be great to be able to run Zynthian with native Arm LV2 plugins on the new M1 Arm based Mac Laptop/Desktop systems. Sadly Linus Torvalds says Apple would have to open the interface of their new GPUs to enable Linux to be ported over)

It turns out a major speedbump in some benchmarks is the Apple defined Bluetooth connection interval, most commonly: interval Min ≥15 ms, but “11.25 ms may be accepted by the (iOS) device” (in macOS it is 7.5ms minimum.)

When used in pairs, these adapters plugged into standard MIDI or USB connectors can bypass these BLE “connection interval” restrictions to achieve low latency.

Two wireless adapters claiming 3ms latency:

They both achieve this performance in a proprietary mode run under BLE 5.0, while eliminating the need for pairing. (A couple of observers suggest with added jitter, the real throughput may have 4–6ms latency)

WIDI Master
CME WIDI Master

Xviveaudio MD1 sm

Roland WM-1
Roland WM-1

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Both of these devices plug into standard MIDI In/Out pairs, stealing power from the MIDI Output connection.
A single one alone makes standard Bluetooth MIDI connections.
Used in pairs to yield the low latency of their proprietary system.

CME WIDI UHOST
CME WIDI Uhost “3 in one” adapter/hub (hopefully the redundant indicator light labels are mockups)
(They want prospects to sign up to their “interested” list, ala kickstarter style to gauge interest level before they will start production.)

CME has 3 other models in planned:

  • WIDI UHOST USB to Bluetooth MIDI $59
  • WIDI PED3 Convert 3 control pedals to Bluetooth MIDI $59
  • WIDI HUB4 Up to 4 Bluetooth MIDI connections simultaneously with ultra low latency $ 199?
    (The WIDI BUD shown on the CME sales page “is no longer manufactured. It will be replaced by the uHost”)


Roland WM-1 USB adapter Only for Windows computers.

(The closed proprietary low latency protocols in these 2 systems are going to slow universal adoption, hopefully hackers will informally document the interface)

A one-way Transmitter-Receiver pair I recently ran across (The midiBeam v2, by pandaMidi, Hungary) claims 0.38 ms latency, and 250 Meter range. (Looks good for a stadium stage runway) They must not be including the initial 1ms MIDI command emission time.

MIDIbeam competor comparison chart


MidiJet Site
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I recently learned that some devices that play together fine with standard MIDI cables, fail when linked with USB cables, in the absense of a USB Host (computer) The WIDI UHOST looks like a device that could be made to also act as a USB host.


The Wave (modulation ring) ‘partnered’ with CME to create a wireless interface that doesn’t require a computer. (I can’t say if it operates in 3ms latency mode, some rings have a dedicated interface box that might be converting raw IMU data to MIDI).
[Juno 60 demo vid. (Their feature review video , disappointing lack of actual sound examples)

References:

Short Roland Press Release September 25, 2020
“The WM-1 will be available for $69.99 and the WM-1D (Windows USB to wireless) will be available for $79.99 in October 2020”

A CME Press Release

Sweetwater WM-1 sales page:
"Extremely low-latency performance: 7.5ms to 15ms in standard mode; 3ms in fast mode "

The Truth About Bluetooth MIDI Wireless MIDI? What about latency? Jan. 2020 (WIDI Master focused)
He suggested Apple choose to not make MIDI a high priority service.

Apple Accessory-Design-Guidelines
See: Page 144 36.6 Connection Parameters
interval Min ≥15 ms
as a HID over GATT keyboard: (If Bluetooth Low Energy HID is one of the connected services of an accessory, connection interval down to 11.25 ms may be accepted by the device.)

2016 article “Maximizing BLE Throughput on iOS and Android” (Part 3 posted April 2019)
Takes an in-depth look at the underlying Latency issues of Bluetooth technology

Music Player Forum discussion of WIDI Master issues
Part 1? . . . . Part 2? Oct 2020

There are issues, including the case of multiple pairs of adapters running in high speed mode, for now, you have to turn them on a pair at a time to control what devices are linked.

Nordic Semi Forum Discussion: Can the connection interval be lower than 30ms on iOS?

My previous rambling post about wireless MIDI

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Hi @MaxMaxis !

Thanks a lot for this fantastic report. I found it really enriching!

Cheers