Review: Zelher P20 Bluetooth Headset

Some time ago I made it clear that I actually prefer a headset with a boom mounted microphone. The Etymotic ETY.COM is an example of such a device, as is the now defunct Plantronics .Audio 615m. It’s also true that the current trend in Bluetooth wireless headsets leans towards designs that are much less conspicuous.

Some months back I became aware of Zelher, a small company that offer a pair of what appeared to be very interesting Bluetooth headsets. I emailed the company inquiring about the products, specifically whether they supported HDVoice. Their response indicated that the company was going to offer a stereo headset for music use later in the year, but said nothing about support for wideband voice in the existing products.

I looked on Amazon to see that the Zelher P20 listed at $99, but was typically offered for around $60. At that price I wasn’t about to buy one just to satisfy my curiosity. A few weeks later I found the P20 offered by a daily deals web site for just $40. That was a bit more tempting.

The discounted price alone was not enough to convince me to part with money. I scoured the companies web site eventually looking through the PDF version of the product manuals. For this I was able to learn that the P20 used a CSR chipset. Looking up that bit of silicon (CSR BC6 V2.1) online it seemed to have support for wideband voice, although I had no way of knowing if Zelher’s implementation in the P20 leveraged this fact.

Intrigued by the design of the P20 headset I took the leap and ordered one. It’s been hanging around my home and office for the past two months. It’s a curious beast, the very fact that it’s a bit unusual implies that there may be some value in sharing my experiences with its use.

The P20 is anything but petite. It’s a single earpiece design with a good long microphone boom. The mic boom rotates around the attach point at the earpiece, making the headset adjustable to be worn on the left or right side.

The mic boom is also flexible, allowing the mic position to be truly customized to the users preference. Just on principle alone I really like this design.

The earpiece is made of a shiny black plastic the reminds me a lot of bakelite. In fact, the P20 reminds me a lot of the headset that I once used on a ham radio as a kid. It has a neat kind of retro-neo look and feel.

The earpiece has a soft leatherette cover making it very comfortable to wear. The headband is quite stout, proving enough pressure to hold the headset firm. In fact, it makes the earpiece seal quite well against my ear.  Unlike a certain other headset that I’ve tried recently, the P20 never feels like it going to fall off my head.

The earpiece is hinged such that it folds into the headband. Even so, the P20 is not the kind of headset that would survive in my computer bag. It’s just too large, and would likely be broken if abused by TSA in my luggage.

The controls are minimal and about what you’d expect. There’s a single silver button to turn the headset off/on and put it into pairing mode. Also a pair of buttons to toggle the volume level.

A micro-USB port in the edge of the earpiece provide a means of charging the P20. It came with a standard AC adapter with a USB port and a USB to micro-USB cable. They also provided a car adapter for automotive use.

I first tried using the P20 with my Samsung Galaxy Nexus cell phone. The headset was easily paired to the phone. Once paired I found that it only supported the headset profile. That meant that I could use it for phone calls but not to listen to media played on the phone.

Further, I could not use the headset to make a recording using the SoundCloud application for Android. This was a bit bothersome. I was trying to experiment with dictating a blog post as described by Walt Mosberg of WSJ. The P20 was simply no help in this regard.

As a cell phone headset it sounded decent. Not outstanding, but decent. I found that the earpiece sealed well enough that a dual earpiece model would leave me wanting side-tone, as was the case with the Plantronics .Audio 480 in the past. This can be an advantage to a user who is working in a very noisy environment.

I made a test recording using the P20 paired to a laptop running the Adobe Audition editor. This represents the optimal quality that could be achieved with the P20. The recording was set for 16 bits at 44.1 KHz sample rate, the equivalent of CD quality.

Despite recording the stream in a high-quality manner the P20 was only able to deliver audio consistent with a PSTN call. The following image is a screen shot showing frequency vs energy plot from this initial test recording. It very clearly shows that the energy is rolled off well below 3.4 KHz.

When I saw that the audio quality was not anywhere near full-band I down-sampled the recording to 16 KHz in order to make the energy plot easier to see. The while line across the image is at 4 KHz.

One of the primary claims made about the Zelher P20 is superior noise reduction. My own experience shows that just using acoustic pickup near the mouth helps this significantly. Acoustic or DSP-based noise suppression can take it a step further. Unfortunately, I’ve yet to devise a practical and meaningful demonstration that might prove such claims.

Zelher claims that the P20 has a very long-lived battery, providing 400 hours of standby time and a whopping 21 hours of talk time. Such claims are well beyond my use case. I charged it only occasionally, perhaps once every week or two. To be fair I only used it occasionally, but I have yet to encounter a low battery warning.

When the P20 was delivered I was immediately taken by its size. In fact, I was reminded of a scene from the movie Madagascar 2: Escape To Africa.

In this scene Gloria (a hippo voiced by Queen Latifa) was meeting the dominant male hippo (Moto Moto, voiced by Will I Am.) He doesn’t know her, but he’s smitten by her sheer size. Hey, it’s a hippo thing.

He says, “Oh baby. You’re huge.” Such was my initial impression of the P20. It’s big, but that’s not necessarily a bad thing.

 

Since others might have that impression as well I thought I’d offer a few pictures to give some perspective to it’s size. The image above shows the P20 flanked by the Sennheiser DW Pro2 and AKG K-240 Studio Headphones. It’s clearly not THAT big when compared to business class office headsets. It’s most definitely large compared to a more common Bluetooth headset, like the minute Plantronics Discovery 975.

The Zelher P20 is definitely an unusual Bluetooth headset. It breaks with the current retail fashion by its sheer size and the long, flexible microphone boom. It’s noise reduction capabilities make it a good choice for someone who would use it primarily while driving or in a noisy office environment. In both situations the extended battery life and noise reduction would be well appreciated despite the dorky appearance of the user.

It’s definitely not the kind of headset that most people would wear while walking out and about. However, given how often I see folks walking around wearing large circumaural headphones, ala Beats Audio, I may be overstating that somewhat.

I would find Zelher’s P20 a lot more interesting if it supported HDVoice. It’s size somewhat narrows it’s application to the auto- or office-bound. In the office I try to take advantage of HDVoice as much as possible. Despite recent improvements in mobile soft phones, I’ve yet to make much use of HDVoice while mobile. That said, at $40 I consider the P20 a decent choice for a certain kind of user…especially if you value battery life over audio quality.

Disclosure: I have no connection to Zelher or it’s parent company. I bought the P20 with my hard earned cash.