## Comparing two Bose headphones, both of which use active technology.

In this posting I’m going to do something I rarely do, which is, something like a product review. I have purchased the following two headphones within the past few months:

The first set of headphones has an analog 3.5mm stereo input cable, which has a dual-purpose Mike / Headphone Jack, and comes either compatible with Samsung, or with Apple phones, while the second uses Bluetooth to connect to either brand of phone. I should add that the phone I use with either set of headphones is a Samsung Galaxy S9, which supports Bluetooth 5.

The first set of headphones requires a single, AAA alkaline battery to work properly. And this not only fuels its active noise cancelling, but also an equalizer chip that has become standard with many similar middle-price-range headphones. The second has a built-in rechargeable Lithium-Ion Battery, which is rumoured to be good for 10-15 hours of play-time, which I have not yet tested. Like the first, the second has an equalizer chip, but no active noise cancellation.

I think that right off the bat I should point out, that I don’t approve of this use of an equalizer chip, effectively, to compensate for the sound oddities of the internal voice-coils. I think that more properly, the voice-coils should be designed to deliver the best frequency response possible, by themselves. But the reality in the year 2019 is, that many headphones come with an internal equalizer chip instead.

What I’ve found is that the first set of headphones, while having excellent noise cancellation, has two main drawbacks:

• The jack into which the analog cable fits, is poorly designed, and can cause bad connections,
• The single, AAA battery can only deliver a voltage of 1.5V, and if the actual voltage is any lower, either because a Ni-MH battery was used in place of an alkaline cell, or, because the battery is just plain low, the low-voltage equalizer chip will no longer work fully, resulting in sound that reveals the deficiencies in the voice-coil.

The second set of headphones overcomes both these limitations, and I fully expect that its equalizer chips will have uniform behaviour, that my ears will be able to adjust to in the long term, even when I use them for hours or days. Also, I’d tend to say that the way the equalizer arrangement worked in the first set of headphones, was not complete in fulfilling its job, even when the battery was fully charged. Therefore, If I only had the money to buy one of the headphones, I’d choose the second set, which I just received today.

But, having said that, I should also add that I have two 12,000BTU air conditioners running in the Summer months, which really require the noise-cancellation of the first set of headphones, that the second set does not provide.

Also, I have an observation of why the EQ chip in the second set of headphones may work better than the similarly purposed chip in the first set…

(Updated 9/28/2019, 19h05 … )

## Is it valid that audio equipment from the 1970s sound better than modern equipment?

That depends on which piece of audio equipment from the 1970s, is being compared with which piece of equipment from today.

If the equipment consists of a top-quality turntable from the late 1970s, compared to the most basic MP3-player from today, and if we assume for the moment that the type of sound file which is being played on the Portable Audio Player, is in fact an MP3 File recorded at a bit-rate of 128kbps, then the answer would be Yes. Top-quality turntables from the late 1970s were able to outperform that.

OTOH, If the audio equipment from today is a Digital Audio Player, that boasts 24-bit sound, that only happens to be able to play MP3 Files, but that is in fact playing a FLAC File, then it becomes very difficult for even the better audio equipment from the 1970s to match that.

Top-Quality Audio Equipment from the late 1970s, would have cost over $1000 for one component, without taking into account, how many dollars that would have been equivalent to today. The type of Digital Audio Player I described cost me C$ 140.- plus shipping, plus handling, in 2018.

Also, there is a major distinction, between any sort of equipment which is only meant to reproduce an Electronic signal, and equipment which is Electromechanical in nature, including speakers, headphones, phonographs… ‘The old Electromechanical technology’ was very good, except for the basic limitation, that they could not design good bass-reflex speakers, which require computers to design well. With no bass-reflex speakers, the older generations tended to listen to stereo on bigger, expensive speakers. But their sound was good, with even bass.

## Overheated Circuitry

One of the things which I do frequently, is ‘walk around’, or, ‘use public transit’, with my disposable earphones plugged in to my Samsung Galaxy S9 Smart-Phone, and listening to music. These earphones are clearly not the ones, which had the AKG seal of approval, and which shipped with the phone. But this week-end marks the second heat-wave this Summer, when outside daytime temperatures exceeded 31⁰C, with direct sunlight and not a cloud in the sky. And under those conditions, the battery of my phone starts to hit a temperature of 42⁰. One of the facts which I know is, that Lithium-Ion batteries like the one in my phone do not tolerate temperatures exceeding 41⁰C.

A peculiar behaviour which has set in for the second time, during this second heat-wave of the season, is that the music I was listening to would either back-space to the beginning of the song, or skip ahead one song, or just stop. So, a catastrophic sort of explanation I could think of would be, that the entire phone, with its battery, is finally just having a meltdown. But, a second possibility exists, that merely the chip in the earphone-cord could be malfunctioning. After all, the little pod in the earphone-cord has one button and a mike, and it’s actually cheaper to mass-produce the chip that makes it work, than it would be to mass-produce other sorts of discrete components. One cheap chip could just be malfunctioning in the extreme heat, and not the entire, complex circuitry of the phone. (:1)

The earphones cost me about \$15, while the phone is much more expensive than that.

But even if it was true, that only the little remote-control in the earphone-cord was malfunctioning, this can lead to impractical situations, because just random patterns, of unreal button-press-combinations, could also send the software of my phone into a confused state, and even so, if the circuitry in the smart-phone never malfunctioned. This behaviour could get misinterpreted by the security apps of the phone, let’s say, as though somebody had ripped the earphone-cord off my head, and thrown all my possessions around.

All that was really happening was that my music was no longer playing, as I was walking home normally, in the heat, with my overheated electronics. And when I got home, my actual phone never displayed any signs of having malfunctioned.

(Updated 8/17/2019, 17h50 … )

## A New Set Of Headphones

As early as This posting, I had experimented with Bluetooth Headphones, that were specifically designed to handle High-Fidelity sound, for continuous music playback. But the fact is, that in the past 2 years, 3 such headphones failed me. The most-recent, ‘Infinim HBS-910′ set also failed on me, mechanically, only earlier this month, which effectively means that in total, if I continued doing things this way, I’d continue to burn through my money too fast.

So the course which I’ve chosen to go instead, is to use wired headphones, but to buy slightly-higher-quality, wired headphones, that are compatible with an Android device.

There once existed the observation, that the buttons on certain headphones would only work with iOS devices, and the buttons on other headphones would only work on Android-based devices. Interestingly enough, If the packaging doesn’t specify, then today, most headphones will work on either devices. My new Headrush HRB 3012 set has buttons which my Samsung Galaxy S6 recognizes.

(Edit 07/14/2018 : )