May 262021
 

So, recently I misplaced the headset adaptor I use for my aging ZTE T83… which is getting on nearly 6 years old now. I had the parts on hand to make a new adaptor, so whipped up a new one, but found the 3.5mm plug would not stay in the socket.

Evidently, this socket has reached the number of insert/remove cycles, and will no longer function reliably. I do like music on the go, and while I’m no fan of Bluetooth, it is a feature my phone supports. I’ve also been hacking an older Logtech headset I have so that I can re-purpose it for use at work, but so far, it’s been about 15 months since I did any real work in the office. Thanks to China’s little gift, I’ve been working at home.

At work, I was using the Logitech H800 which did both USB and Bluetooth. Handy… but one downside it had is it didn’t do both, you selected the mode via a slider switch on the back of one of the ear cups. The other downside is that being an “open ear” design, it tended to leak sound, so my colleagues got treated to the sound track of my daily work.

My father now uses that headset since he needed one for video conferencing (again, thank-you China) and it was the best-condition headset I had on hand. I switched to using a now rather tatty-looking G930 before later getting a ATH-G1WL which is doing the task at home nicely. The ATH-G1WL is better all-round for a wireless USB headset, but it’s a one-trick pony: it just does USB audio. It does it well, better than anything else I’ve used, but that’s all it does. Great for home, where I may want better fidelity and for applications that don’t like asymmetric sample rates, but useless with my now Bluetooth-only phone.

I had a look around, and found the Zone Wireless headset… I wondered how it stacked up against the H800. Double the cost, is it worth it?

Firstly, my environment: I’m mostly running Linux, but I will probably use this headset with Android a lot… maybe OpenBSD. The primary use case will be mobile devices, so my existing Android phone, and a Samsung Active3 8″ tablet I have coming. The fact this unit like the H800 does both Bluetooth and USB is an attractive feature. Another interesting advertised feature is that it can be simultaneously connected to both, unlike the H800 which is exclusively one or the other.

First impressions

So, it turned up today. In the box was a USB-C cable (probably the first real use I have for such a cable), a USB-A to USB-C adaptor (for all you young whipper-snappers with USB-C ports exclusively), the headset itself, the USB dongle, and a bag to stow everything in.

Interestingly, each of these has a set-up guide. Ohh, and at the time of writing, yes, there are 6 links titled “Setup Guide (PDF)”… the bottom-right one is the one for the headset (guess how I discovered that?). Amongst those is a set-up guide for the bag. (Who’d have thought some fabric bag with a draw-string closure needed a set-up guide?) I guess they’re aiming this at the Pointy Haired Boss.

Many functions are controlled using an “app” installed on a mobile device. I haven’t tried this as I suspect Android 4.1 is too old. Maybe I can look at that when the tablet turns up, as it should be recent enough. It’d be nice to duplicate this functionality on Linux, but ehh… enough of it works without.

Also unlike the H800… there’s nowhere on the headset to stash the dongle when not in use. This is a bit of a nuisance, but they do provide the little bag to stow it in. The assumption is I guess that it’ll permanently occupy a USB port, since the same dongle also talks to their range of keyboards and mice.

USB audio functionality

I had the Raspberry Pi 3 running as a DAB+ receiver, Triple M Classic Rock had The Beatles Seargeant Pepper’s Lonely Hearts Club Band album on… so I plugged the dongle in to see how they compared with my desktop speakers (plugged in to the “headphone” jack). Now this isn’t the best test for sound quality for two reasons: (1) this DAB+ station is broadcasting 64kbps HE-AAC, and (2) the “headphone” jack on the Pi is hardly known as high fidelity, but it gave me a rough idea.

Audio quality was definitely reasonable. No better or worse than the H800. I haven’t tried the microphone yet, but it looks as if it’s on par with the H800 as well. Like every other Logitech headset I’ve owned to date, it too forces asymmetric sample rates, if you’re looking at using JACK, consider something else:

stuartl@vk4msl-pi3:~ $ cat /proc/asound/Wireless/stream0
Logitech Zone Wireless at usb-3f980000.usb-1.4, full speed : USB Audio

Playback:
  Status: Running
    Interface = 2
    Altset = 1
    Packet Size = 192
    Momentary freq = 48000 Hz (0x30.0000)
  Interface 2
    Altset 1
    Format: S16_LE
    Channels: 2
    Endpoint: 3 OUT (NONE)
    Rates: 48000
    Bits: 16

Capture:
  Status: Stop
  Interface 1
    Altset 1
    Format: S16_LE
    Channels: 1
    Endpoint: 3 IN (NONE)
    Rates: 16000
    Bits: 16

The control buttons seem to work, and there’s even a HID device appearing under Linux, but testing with xev reveals no reaction when I press the up/down/MFB buttons.

Bluetooth functionality

With the dongle plugged in, I reached for my phone, turned on its Bluetooth radio, pressed the power button on the headset for a couple of seconds, then told my phone to go look for the device. It detected the headset and paired straight away. Fairly painless, as you’d expect, even given the ancient Android device it was paired with. (Bluetooth 5 headset… meet Bluetooth 3 host!)

I then tried pulling up some music… the headset immediately switched streams, I was now hearing Albert Hammond – Free Electric Band. Hit pause, and I was back to DAB+ on the Raspberry Pi.

Yes, it was connected to both the USB dongle and the phone, which was fantastic. One thing it does NOT do though, at least out-of-the-box, is “mix” the two streams. Great for telephone calls I suppose, but forget listening to something in the background via your computer whilst you converse with somebody on the phone.

The audio quality was good though. Some cheaper Bluetooth headsets often sound “watery” to my hearing (probably the audio CODEC), which is why I avoided them prior to buying the H800, the H800 was the first that sounded “normal”, and this carries that on.

I’m not sure what the microphone sounds like in this mode. I suspect with my old phone, it’ll drop back to the HSP profile, which has an 8kHz sample rate, no wideband audio. I’ll know more when the tablet turns up as it should be able to better put the headset through its paces.

Noise cancellation

One nice feature of this headset is that unlike the H800, this is a closed-ear design which does a reasonable amount of passive noise suppression. So likely will leak sound less than the H800. Press the ANC button, and an announcement reports that noise cancellation is now ON… and there’s a subtle further muffling of outside noise.

It won’t pass AS/NZS:1270, but it will at least mean I’m not turning the volume up quite so loud, which is better for my hearing anyway. Doing this is at the cost of about an hour’s battery life apparently.

Left/right channel swapping

Another nice feature, this is the first headset I’ve owned where you can put the microphone on either side you like. Put the headset on either way around, flip the microphone to where your mouth is: as you pass roughly the 15° point on the boom, the channels switch so left/right channels are the correct way around for the way you’re wearing it.

This isn’t a difficult thing to achieve, but I have no idea why more companies don’t do it. There seems to be this defacto standard of microphone/controls on the left, which is annoying, as I prefer it and controls on the right. Some headsets (Logitech wired USB) were right-hand side only, but this puts the choice in the user’s hands. This should be encouraged.

Verdict

Well, it’s pricey, but it gets the job done and has a few nice features to boot. I’ll be doing some more testing when more equipment turns up, but it seems to play nice with what I have now.

The ability to switch between USB and Bluetooth sources is welcome, it’d be nice to have some software mixing possible, but that’s not the end of the world, it’s an improvement nonetheless.

Audio quality seems decent enough, with playback sample rates able to match DVD audio sample rates (at 16-bits linear PCM). Microphone sample rate should be sufficient for wideband voice (but not ultra-wideband or fullband).

It’s nice to be able to put the microphone on the side of my choosing rather than having that dictated to me.

The audio cancellation is a nice feature, and one I expect to make more use of in an open-plan environment.

The asymmetric record/playback sample rates might be a bit of a nuisance if you use software that expects these to be symmetric.

Somewhere to stash the dongle on the headset would’ve been nicer than having a carry bag.

It’d be nice if there was some sort of protocol spec for the functions offered in the “app” so that those who cannot or choose not to run it, can still access those functions.

Jun 212020
 

So, for a decade now, I’ve been looking at a way of un-tethering myself from VoIP and radio applications. Headsets are great, but it does mean you’re chained to whatever it’s plugged into by your head.

Two solutions exist for this: get a headset with a wireless interface, or get a portable device to plug the headset into.

The devices I’d like to use are a combination of analogue and computer-based devices. Some have Bluetooth… I did buy the BU-1 module for my Yaesu VX-8DR years, and still have it installed in the FTM-350AR, but found it was largely a gimmick as it didn’t work with the majority of Bluetooth headsets on the market, and was buggy with the ones it did work with.

Years ago, I hit upon a solution using a wireless USB headset and a desktop PC connected to the radio. Then, the headset was one of the original Logitech wireless USB headsets, which I still have and still works… although it is in need of a re-build as the head-band is falling to pieces and the leatherette covering on the earpieces has long perished.

One bug bear I had with it though, is that the microphone would only do 16kHz sample rates. At the time when I did that set-up, I was running a dual-Pentium III workstation with a PCI sound-card which was fairly frequency-agile, so it could work to the limitations of the headset, however newer sound cards are generally locked to 48kHz, and maybe support 44.1kHz if you’re lucky.

I later bought a Logitech G930 headset, but found it had the same problem. It also was a bit “flat” sounding, given it is a “surround sound” headset, it compromises on the audio output. This, and the fact that JACK just would not talk to it any higher than 16kHz, meant that it was relegated to VoIP only. I’ve been using VoIP a lot thanks to China’s little gift, even doing phone patches using JACK, Twinkle and Zoom for people who don’t have Internet access.

I looked into options. One option I considered was the AstroGaming A50 Gen 4. These are a pricey option, but one nice feature is they do have an analogue interface, so in theory, it could wire direct to my old radios. That said, I couldn’t find any documentation on the sample rates supported, so I asked.

… crickets chirping …

After hearing nothing, I decided they really didn’t want my business, and there were things that made me uneasy about sinking $500 on that set. In the end I stumbled on these.

Reading the specs, the microphone frequency range was 30Hz to 20kHz… that meant for them to not be falsely advertising, they had to be sampling at at least 40kHz. 44.1 or 48kHz was fine by me. These are pricey too, but not as bad as the A50s, retailing at AU$340.

I took the plunge:

RC=0 stuartl@rikishi ~ $ cat /proc/asound/card1/stream0 
Unknown manufacturer ATH-G1WL at usb-0000:00:14.0-4, full speed : USB Audio

Playback:
  Status: Running
    Interface = 1
    Altset = 1
    Packet Size = 200
    Momentary freq = 48000 Hz (0x30.0000)
  Interface 1
    Altset 1
    Format: S16_LE
    Channels: 2
    Endpoint: 1 OUT (ADAPTIVE)
    Rates: 48000
    Bits: 16

Capture:
  Status: Running
    Interface = 2
    Altset = 1
    Packet Size = 100
    Momentary freq = 48000 Hz (0x30.0000)
  Interface 2
    Altset 1
    Format: S16_LE
    Channels: 1
    Endpoint: 2 IN (ASYNC)
    Rates: 48000
    Bits: 16

Okay, so these are locked to 48kHz… that works for me. Oddly enough, I used to get a lot of XRUNS in jackd with the Logitech sets… I don’t get any using this set, even with triple the sample rate. This set is very well behaved with jackd. Allegedly the headset is “broadcast”-grade.

Well, not sure about that, but it performs a lot better than the Logitech ones did. AudioTechnica have plenty of skin in the audio game, have done for decades (the cartridge on my father’s turntable… an old Rotel from the late 70s) was manufactured by them. So it’s possible, but it’s also possible it’s marketing BS.

The audio quality is decent though. I’ve only used it for VoIP applications so far, people have noticed the microphone is more “bassy”.

The big difference from my end, is notifications from Slack and my music listening. Previously, since I was locked to 16kHz on the headset, it was no good listening to music there since I got basically AM radio quality. So I used the on-board sound card for that with PulseAudio. Slack though (which my workplace uses), refuses to send notification sounds there, so I missed hearing notifications as I didn’t have the headset on.

Now, I have the music going through the headset with the notification sounds. I miss nothing. PulseAudio also had a habit of “glitching”, momentary drop-outs in audio. This is gone when using JACK.

My latency is just 64msec. I can’t quite ditch PulseAudio, as without it, tools like Zoom won’t see the JACK virtual source/sink… this seems to be a limitation of the QtMultimedia back-end being used: it doesn’t list virtual sound interfaces and doesn’t let people put in arbitrary ALSA device strings (QAudioDeviceInfo just provides a list).

At the moment though, I don’t need to route between VoIP applications (other than Twinkle, which talks to ALSA direct), so I can live with it staying there for now.