I’m a stong advocate for safeguarding your listening to from noise-induced listening to loss (NIHL). This is an even bigger downside as we speak than ever earlier than, particularly since so many individuals hearken to music from their transportable units on headphones, typically cranking the quantity to unsafe ranges.
Electronics specialist Dave Russell turned involved when his younger daughter began affected by NIHL as a result of she was listening to music on headphones at excessive ranges for lengthy durations of time. He based Puro Sound Labs to develop high-quality headphones for teenagers that assist defend their listening to.
Two years in the past, TechHive reviewed Puro Sound’s previous models, the BT2200 for teenagers and BT5200 for adults. Now, Puro Sound has launched a brand new mannequin, the PuroQuiet, which provides energetic noise cancellation (ANC). Can it assist stem the tide of NIHL in children? I used to be keen to search out out.
PuroQuiet function set
The PuroQuiet is an on-ear headphone—that’s, the earcups sit on the ears slightly than round them, although I suppose they could match round a small youngster’s ears. The earpads and headband are wrapped in what the Puro Sound web site calls “protein leather,” and so they weigh slightly below six ounces, which could be very light-weight.
The PuroQuiet has a fancy construction, as seen on this exploded view.
Sound is reproduced by 40mm dynamic drivers with neodymium magnets aided by a Qualcomm CSR 8635 DSP (digital sign processing) chipset. Frequency response is specified from 20Hz to 20kHz (no tolerance given).
The main audio enter is Bluetooth 4.0 from any appropriate supply machine. Supported profiles embrace A2DP, AVRCP, HFP, and HSP (aptX will not be supported, regardless of the Qualcomm chip). A 3.5mm two-channel analog-audio jack can be obtainable on the underside of the fitting earcup. If the battery dies, you possibly can join a supply machine to the headphone with the included cable (or any 3.5mm audio cable) and proceed having fun with your tunes.
The PuroQuiet approaches listening to safety in 3 ways. First, the corporate claims 82 % passive noise isolation at 1kHz just by carrying the headphone. This appears fairly excessive to me, particularly for on-ear headphones. Most of the corporate’s supplies point out 82 % noise isolation with out specifying the frequency, which appears a bit deceptive.
In response to my queries about this, the corporate knowledgeable me that the isolation issue will increase with frequency. It’s comparatively flat from about 300Hz to roughly 2kHz, and it will increase dramatically above that. There will not be a lot isolation beneath 300Hz, as seen within the graph beneath.
According to Puro Sound Labs testing, ANC (purple line) reduces ambient noise ranges by 18-22dB beneath 500Hz. Passive isolation (inexperienced line) will increase with frequency, from about 10dB at 200Hz to greater than 50dB at 10kHz. This graph is barely an estimation based mostly on in depth measurements.
Also, like the corporate’s BT2200 and BT5200, the sound strain stage is alleged to be restricted to 85dB, which is mostly accepted as the utmost secure stage for long-term publicity (eight hours, in accordance with the Hearing Health Foundation). Puro Sound doesn’t specify if this restrict is expressed in A-weighted decibels (dBA), flat (dBZ), or another weighting, and I didn’t get a solution to this query by the point I wanted to show within the evaluate. I believe it’s dBZ, although the OSHA and commercial-cinema requirements specify an common stage of 85dBA for eight hours—which signifies that the momentary stage can exceed 85dBA supplied the typical over eight hours doesn’t go above that stage. Whatever the weighting, 85dB remains to be too excessive for my part, however that’s simply me—and my 30 years of expertise researching this matter.
Finally, the PuroQuiet integrates energetic noise cancellation, which inverts the section of sound picked up by a single microphone within the headphone and mixes it with the unaltered sound, thereby lowering the perceived stage because of section cancellation. The thought is that this: If the ambient noise stage is lowered, customers can drop the quantity and nonetheless have an pleasurable listening expertise whereas subjecting their listening to to decrease ranges general.
The PuroQuiet ANC is alleged to supply 22dB of noise discount beneath about 500Hz, the place most steady-state ambient noise exists. The effectiveness of ANC begins rolling off above 500Hz, and it’s fully ineffective above 700Hz or so, as seen within the following graph.
PuroQuiet battery life
Of course, such know-how requires a battery. The PuroQuiet’s 290 mAh battery expenses in about three hours and gives energy for 16 hours with ANC engaged or 22 hours with out ANC.
As with most wi-fi headphones, the PuroQuiet additionally features as a telephone headset; a second microphone is constructed into the unit to serve that operate. A single multifunction button helps you to reply, reject, and grasp up calls on the paired telephone. You may even switch calls from the headphone to the telephone and again once more. Naturally, the music pauses throughout a name.
PuroQuiet’s person controls
Most of the controls are discovered on the again of the left earcup, and they’re easy sufficient for a kid to function. They embrace the aforementioned multifunction button, an influence on/off slider, and separate quantity up and down buttons. Aside from its telephone duties, the multifunction button initiates Bluetooth pairing in addition to beginning and pausing playback. There isn’t any skip ahead/backward management. The again of the fitting earcup has a slider that turns ANC on and off.
Most of the controls are discovered on the again of the left earcup, together with the multifunction/Bluetooth button, energy on/off, and quantity up and down. The ANC on/off slider is on the again of the fitting earcup.
A micro-USB port on the underside of the left earcup helps you to cost the battery by connecting the port to a USB energy supply (5V, 2A), and the PuroQuiet comes with an applicable cable. An LED subsequent to the micro-USB port signifies the charging and Bluetooth standing. The 3.5mm enter is on the underside of the fitting earcup together with one other LED that signifies ANC standing.
Puro Sound touts the sturdy building of the PuroQuiet, which makes use of AL6063 aluminum for its outer casing and headband extenders. It appears fairly sturdy to me, however on my pattern, the micro-USB port was not effectively aligned with its gap within the outer casing, making it a bit troublesome to insert the connector for charging. That might be an issue for small, impatient fingers.
Performance analysis
Pairing the PuroQuiet to my iPad went with no hitch. When I first put the headphone on, it felt very tight on my head. Granted, it’s supposed for teenagers, although the web site says “The suggested age range of using PuroQuiet is from 2 to 92 years old.” Also, my head is kind of massive within the bodily sense—I put on a 7 3/4 hat dimension. As a end result, I discovered this headphone to be pretty uncomfortable for lengthy listening classes, however that shouldn’t be an issue for these with smaller heads.
Although Puro Sound Labs says individuals of any age can use these headphones, individuals with massive heads would possibly discover them uncomfortable (they shouldn’t be an issue for teenagers, after all).
I began my listening with “Green Instrument” from the album Seed by world-trance artist Afro Celts. The instrumentation is usually synthesizers with electrical bass, percussion, and Irish flute. Without ANC, the sound was fairly thick and closed in; partaking ANC, the sound opened up significantly, with a a lot clearer midrange, ethereal highs, and fewer boomy bass. Also, the general stage appeared to extend a bit on the identical quantity setting.
From a special a part of the world, I listened to Itzhak Perlman and the Klezmatics play “Golem Tants” from Live within the Fiddler’s House. This energetic Klezmer music—the folks music of Eastern European Jews—consists of violin, clarinet, trumpet, bass clarinet, piano, and electrical bass. My expertise with and with out ANC had been a lot the identical as earlier than: congested sound that lacked midrange with out ANC; a lot cleaner and well-balanced sound with ANC.
Turning to pop/rock, I listened to Fleetwood Mac’s “Little Lies” from their Greatest Hits album. Without ANC, the lead and background vocals had been obscure, and the sound felt clogged, as if I used to be listening via a tube. With ANC engaged, the sound opened up dramatically and appeared a bit louder.
In the classical style, I sampled the Bizet opera Les Pecheurs de Perles; particularly, Amis, Interrompez vos Danses from Act 1 as carried out by the Paris Opera Orchestra and Chorus below the route of Georges Pretre. Once once more, the distinction between ANC on and off was apparent. Without it, the sound was very closed in and the soloists had been obscured. Turning ANC on, the sound opened up considerably and the solos had been a lot clearer.
As I used to be listening to music from my mobile phone, I requested my spouse to name. The music paused and I pushed the multifunction button to reply the decision, which labored precisely as anticipated. My spouse reported that my voice had a tinny, metallic character, however my speech was solely intelligible. Her voice sounded a bit skinny within the headphone, however we might keep it up a dialog with no downside.
The earcups fold flat to slot in the included hard-shell case.
Testing, Testing, 1, 2, 3
I used to be interested by testing Puro Sound’s declare that the PuroQuiet limits the output stage to not more than 85dB SPL. Also, I needed to objectively study the impact of ANC. So, I pulled out my calibrated measurement microphone (an iTestMic), which is designed to work with the AudioTools iOS app from Studio Six Digital.
I used the SPL Graph module inside AudioTools on my iPhone 6. The module measures SPL over time and gives numerous metrics, together with Leq (common RMS stage over the complete size of the measurement), Lmax (most 1-second RMS stage throughout the measurement), L50 (RMS stage exceeded 50% of the time throughout the measurement), L10 (RMS stage exceeded 10 % of the time throughout the measurement), and L01 (RMS stage exceeded 1 % of the time throughout the measurement).
For the check materials, I chosen “White Room” by Cream, performed from the identical iPad I had used for many of my listening. I cranked the quantity to most and performed the tune twice—as soon as with ANC off and once more with ANC on—whereas pointing the microphone instantly into the middle of the fitting earcup. The mic has a windscreen, so I let it relaxation on the inside floor of the earcup.
With ANC off, Leq was 65.5dBA (A-weighted) and 66.9dBZ (flat). Lmax was 76.7dBZ, and L01 was 71.6dBZ. In different phrases, the utmost 1-second stage was solely 76.7dBZ, and the extent exceeded 71.6dBZ solely 1 % of the time. That is all effectively beneath the 85dBZ restrict.
Turning ANC on, Leq was 70.5dBA and 72.0dBZ, Lmax was 96.8dBZ, and L01 was 77.7dBZ. Obviously, the extent was increased with ANC engaged, and Lmax exceeded 85dBZ by greater than 10 dB! That was just for one second, nevertheless, and the extent remained effectively beneath 85dBZ greater than 99 % of the time.
In addition to measuring SPL metrics, the SPL Graph module additionally gives an RTA (real-time analyzer) with 1/3-octave bands. As you possibly can see within the following display pictures from the app, there’s a distinct drop within the low midrange with ANC off, whereas the spectrum is rather more balanced with ANC on, confirming my subjective impressions. Of course, these graphics are solely a snapshot of 1 second; the spectrum diversified over time. But the RTA revealed these common spectral shapes all through the measurement.
With ANC off, the low midrange is considerably poor, confirming my sense that the sound was missing in that area.
With ANC on, the general spectral stability was significantly better, leading to a cleaner, clearer sound. Also, the extent was increased general than with ANC off at a given quantity setting.
For my ultimate check, I drove round my neighborhood whereas carrying the PuroQuiet—holding a pointy eye out for cops! I turned ANC on and off as I listened to music and with no music. The noise-cancelling operate labored very effectively, vastly lowering the extent of engine noise. As earlier than, the sound high quality was significantly better with ANC on.
I additionally checked ANC in a quiet room with no music. It exhibited a slight hiss, however that isn’t an issue in a loud atmosphere.
PuroQuiet headphones are a stable worth
I applaud Puro Sound Labs for its dedication to defending youngsters’s listening to. The PuroQuiet headphone is a worthy testomony to that dedication, offering three-way safety: passive isolation, quantity limiting, and energetic noise cancellation.
In my checks, the extent by no means acquired near 85dBZ with the quantity maxed out and ANC turned off, but it surely did momentarily exceed that stage with ANC on. Still, the extent remained effectively beneath 85dBZ greater than 99 % of the time, so I don’t assume that momentary peak is an enormous deal. Overall, the extent remained effectively throughout the secure zone throughout my listening.
The ANC works very effectively at lowering the extent of low-frequency ambient noise, and it additionally considerably improves the sound high quality—the truth is, I like to recommend listening with ANC on on a regular basis, even in quiet environments. Of course, that additionally reduces the battery life, but it surely’s nonetheless fairly spectacular at 16 hours. Also, the general stage with ANC on is considerably increased than when it’s off, so you possibly can again off the quantity management to guard your listening to much more.
Although the Puro Sound Labs web site says the PuroQuiet is supposed for ages 2 to 92, I discovered the headphone too small for consolation on my (admittedly massive) head. But this must be no downside in any respect for youngsters.
The checklist value of $199.99 is fairly excessive, however the construct high quality is stable, which is vital for careless children. Even higher, the PuroQuiet is promoting for $149.99 on the Puro Sound website for a restricted time. (They received’t inform me when that value will return as much as full checklist.) Either means, it’s a comparatively small value to pay for the peace of thoughts understanding that you simply’re defending your children’ listening to.