Thursday, 22 September 2022

Bose QuietComfort Buds (the case as a stand)

I just discovered that the case that the (Series 1) buds come in can act as a nice stand to hold them (while on a desk or dash??) and not be charging


I spotted this little bit in the bottom of the case and discovered that you can just put them in nose down ...


which makes them easy to grab and put in your ear


so this makes the case much more appealing to me than it was.


HTH

Monday, 19 September 2022

First generation Bose QuietComfort Buds (a review of sorts)

These things are not new, but its not quite 2 years since they were first introduced to the market (so they're not really old either). Yet Bose has just released the QuietComfort II buds (I'm going to call these the QCB's and QCB2's respectively) which some think are set to replace the model which I'm reviewing. That may be, but for now you can get this model cheaper. I got mine a lot cheaper by buying 'refurbished' ones for under AU$200 (and no they aren't fakes). This is them in the case which is also the charging unit.

QCB

No doubt you've seen many reviews already (if you are even remotely searching these things), so you'll know most of the basics on them. I'll skip that, and I'll also say from the start that this is not a typical review. Why? Well because I largely think reviewers are some combination of
  • wankers
  • idiots
  • technically inept
  • inexperienced kids
  • liars
  • shills
I've written on this topic before where I argue that (in the main) reviewers are the problem. So if you wanted someone to stroke your genitals while you decide if you should buy these you've come to the wrong site.

What experience do I have?

Up front I don't like modern buds. The reasons are pretty simple, you have to squish them into your ear. When in your ear they change how you hear everything else. Because of the direct acoustic coupling to your ear canal they amplify any sounds you make with your voice or even if you just scratch your chin, In short they have all the disadvantages of Hearing Safety ear plugs but without anything like the level of protection that they provide in a noisy environment.

Worse they dull your situational awareness, as hearing is important to detecting threats like; cars, busses and other obstacles in a crowded environment (where kiddies often wear them and walk under a bus while engrossed in their little bubble). So be careful when using these things.

I do own buds and have used; heaphones, over ear clips, in ear buds and whatnot for most of my life. I had a Sony Walkman when they came out, and its fair to say I've used these things extensively in many environments. This is my previous bench mark in-ear bud style headphones:


They are Koss brand and, as you can tell from the marks and buffing that on little case, they've been around. I bought them in 1985 or so (when I was delivery driving for my dads business) to use with my walkman. I have used them in the office daily for years as well as when listening to music or language lessons. These things have been through much with me: Japan, India, Finland, Europe. 

The key thing here is not only are they comfortable, sound good and are compact and easy to carry, they still fucking work (although the trend away from 3.5mm sockets is killing this).

I did find however that another type I bought in the 2000's (in Japan) were these:



These little Sony's became my goto for a long time (yes, they still work too) as they were more comfortable to wear in the office, allowed the ear to breath better and (importantly and I'll come back to this) passed through everything (like conversation) as if they weren't there. This allowed me to listen to music privately while still remaining part of a team.

So basically I'm saying I've been in this space for decades. With respect to Active Noise Cancellation (ANC) I have had Bose headphones for over 10 years now starting with the QuietComfort QC-2 over ear headphones which were game changers for long haul flights and noisy open plan offices. I still use the QC-2's for field recording of ambient sounds and bird calls. 

I currently use QC35 II headphones pretty much daily; for office, for car phone calls, for general music listening (that isn't speakers). However knowing how "sweaty" things get in summer and starting a job where I will make a lot of support calls I wanted to have some alternative. Hence the QC buds.

So getting back to the Bose Quiet Comfort buds...

Having said all of the above and given that they are buds of the worst type (squished in / sealing the ear typethese things are simply amazing, they have exceeded my pre-purchase expectations in every way (except that annoying physical acoustic coupling which you get with ear plugs, where my deep breaths are heard, scratching my head is heard and anything touching them (like a hoodie) is amplified right into my ear hole). I think there is a solution to that, but as the marketing tail is currently wagging the engineering dog I don't expect (looking at the Bose web site) the solution will ever emerge.

My usage case...

I do an amount of driving, and my car is an old 4WD (lets leave my motorcycle out of this) and want to be able to make and take hands free calls when in my car. I've found that the ANC changes on incoming calls to act in some way towards making my environment less noisy for the listener, that's important to me. I first knew of this when I took a call (with my QC35 II's) in my 4WD on my way home from work on the highway and my friend say "oh, are you in the office, can you talk right now or should I get you on the way home".  I was impressed and said to him "no, I was in the car on the way home" and we discussed how good the audio of my voice in my environment was for him. Top points awarded. It was then that I noticed that when a call comes in I can hear more of my cabin noise in my own ears as well as some of my voice. This pass through was good and I reckon it contributes to me not unconsciously yelling (because I can't judge my own volume due to the cancellation). 

This experience forms the basis of my expectation with the buds, and as I said at the start they have exceeded my expectation (no easy feat).

Whats good?

That I can drive down a corrugated dirt road in my rattily 4WD and have a conversation is fantastic, that I can do it without over ear headphones is even better. In Winter I don't mind the over ear nature of the QC35 II's but they do making putting on and taking off sunglasses a bit more cumbersome and many sunglasses break the head seal of the cans and allow some background to bleed in. These buds of course get around that problem.

So by not sitting on my head I can get good air ciculation, put on / take off sunglasses and or optical glasses as needed.


When wearing them unlike the "bullet" shaped plugs these are a bit different, they are sort of a cone (or lamp shade shape) and a support to hold it more securely ...


without that "suction cup" effect when putting them in or taking them out and which fits in the ear nicely:


Putting them in is sort of an insert and twist backwards that slides in and tightens up.

In Summer it means that my ears won't get as sweaty but I'll still get the advantages of ANC. I happen to prefer a standing desk and when on the phone to a client like to be able to move a bit, pace, whatever. Wireless is good, and I'd hoped that these Buds would mean that my ears wouldn't be wearing ear-muffs for lengthy times. As a Developer at my desk beavering away on code in a noisy (but air conditioned office) the QC 35 II's did get a bit sweaty even in the AC in summer, in the car it was much more pronounced ... like a sauna for my ears when I faced a 2 hour drive.

The Aware mode is great for almost all situations. It also passes through so well I can hear conversations well enough (great for when my workmates are actually talking to me and saves me taking out the buds if I don't want to) with just a quick double tap.

There are three settings to cycle through (on the version of the firmware I have, I understood that earlier ones had only two) and customisation in the App (on my phone or tablet) allows me to have more. I've set my three up to be:

  1. Aware - almost no ANC
  2. Commute - about 4 out of 10 setting on ANC
  3. Quiet - full ANC
I could add more but really I'm quite ok with those three to cycle through.

To compare these for the intended purpose I've taken my 4WD for a drive along a rough dirt road while talking to a friend on the phone. I used the QCB and the QC35II's and he found that (from his perspective) both did a very good job of noise cancellation. This is in an environment where it is so noisy in the cabin you'd be yelling at each other to hear.

Next I have mowed the lawn while listening to quiet music playing through the QCB's ... I could still hear the music (without turning it up) and found the result was similar to putting in a pair of noise reducing safety ear plugs.



I call that set of results: Pass, with flying colours.

What's not to like

Simple: they are buds, and thus when wearing them; 

  • chewing,
  • coughing, 
  • swallowing and 
  • scratching my head 
now conducts through to my ears in a way I don't like (just like when you wear ear plugs). Not many reviewers mention that and act as if its not a feature.

As well touching them (to adjust volume, hang up, skip a track or change mode) is also acoustically annoying too.  In this way I much prefer the QC35II's to these.

If you forget to put them into the case to recharge (having taken them out for some reason) then by morning they'll be nearly flat (so the hibernation isn't as good as it could be). Lacking any sort of switch (as the QC35II's have) I of course need to put them into the case for charging when I'm not using them. So if I'm not using them for a few days (this happens) then they'll be at full charge most of the time. Anyone with knowledge of how Li-ION works knows that's a recipe for reduced battery life. Actually if I take them off and just put them down they won't even work after 24 hours. So you need to be returning them to the case.

In contrast, with my QC35II's I (can) turn them off as I take them off and so they can sit for days or even weeks at somewhere around 50% and I know that will give the maximum life of the battery. I've had them since 2019 and the battery is doing well. I doubt that this will be the case for these.

Because the case is also a battery charger that's yet another battery I need to pay attention to (if I don't want to be buying a new set every year or so because the battery isn't working).

Unlike my little Koss headphones the case won't fit in a pocket, so that means I really do need to keep my backpack with me for that.

Generally the feeling is "if you have to think about money then you can't afford it", but given the advertising on their WWW site Bose are aiming at kids who have no concept of fiscal responsibility (or are drug dealers).

The app ... aside from using it to make any configuration and customisation its just dead space on your phone. Mine silently failed on my (admittedly 4 year old) phone, but worked fine on another device (Android Tablet)

So the above negatives may seem inconsequential to you and if they do then that's good as there are even less downsides.

Where will this model go?

Well, as Yoda said "Hard to see, the future is" so with that said I'd say that the QCB will likely slip into being discontinued and the QCB2 will take over. I mean its possible that they'll keep the original QCB on cheaper than the QCB2 but I doubt it.

If you are bargain oriented keep an eye on the Bose outlet store for refurbished QCB's as these will likely be about half the price.

Personally I like the size of the QCB and (not having tried them) suspect that the QCB2's will be a bit fiddly to use.

What would I like to see?

Well given that these things are already so minature I'd love to see an ear clip type of over ear type similar to my Sony. We've already seen (quite some time ago) Bose QuietComfort 3 over ear headphones which had pretty good ANC. From the Bose site:


(link)


While it may not be possible to get over ear style being as totally isolating as squish plugs into your ear type buds, actually having such perfect ANC isolation may not be ideal. Perhaps the reality is  that when being out and about its is actually dangerous to be so isolated from sounds.



... as that idiot found out (which is better than got killed and didn't). Perhaps we shouldn't be aiming for 100% ANC?

So on point below is a quick and dirty of what my ideal over ear ANC system would look like without wires


Myself I'd gladly sacrifice a little perfection in isolation if the trade off is more comfort and not needing things squished into my ears (thus conducting the physical sounds of my body into my ears).

In Summary

I recommend the Bose QCB (generation 1) but reserve judgement on the QCB2's until I get them to compare.

HTH

PS: I've discovered how to make the case a holding stand (see this link).


Saturday, 3 September 2022

(battery charging, and) Cells in a Battery

When I built my shed I knew I'd need power down there and so it immediately occurred to me that this was an excellent opportunity to conduct a practical (and beneficial) experiment in "Off Grid" solar. 

I knew that while I understood a lot of the theory, its often the case that some surprises occur in the actual operation. This blog post is about an expectation that was fulfilled: cell imbalance in flooded lead acid batteries.

This issue is important to anyone choosing lead acid chemistry in an off grid application because it leads to premature death of your (often expensive) investment in batteries. The reason for 24V is that I want to use the energy in the battery to power things which are made for AC, thus I need an inverter. The above mentioned blog post has a few more details.

the invisible (to most people) issue

People never think past words, like "battery".  A battery is not just an indivisible block, but basically a connected series of cells each depending on the other (check the word battery in a dictionary).

Charging a cell is straightforward, but charging batteries is more complex than people usually consider. This is because while each cell needs to be charged equally we apply a voltage across the entire battery and "magic happens"; where the battery magically stores the energy. 

If only it was this simple there wouldn't be any problems.


Above is a picture of my 24V battery system for my solar shed, the battery system was commissioned  (fancy word for the relatively simple process, sorry) in early March but as you see the battery dates are 4th of Feb (which is why dear American readers the rest of the world writes 4/2/22 and your Month Day Year format is frankly 0.o

As you can see I have two 12V batteries connected in series to make a 24V battery, and each 12V battery has a small volt meter on it. I did this as I wanted make voltage checking a simple matter (rather than kneel down on the floor with my volt meter). I wanted to check because I wanted this to be an experiement in exploring why batteries fail early. 

I believe batteries fail  early because of unaddressed issue in imbalances. Of course I'd like to improve on this situation, but that's pretty much impossible with the way modern batteries are made and (a big hint to off gridders to select batteries appropriately) how batteries are connected for charging.

Probably the first thing you can see there is that the voltages are different between each 12V lead acid battery. 

  • B1 is 13.3V
  • B2 is 13.6V
This wasn't always like this, as back in Feb they were both new and both within 0.01V of each other. Somehow that balance has changed. Leading me to my point about balance:

The Balancing Act

So we get to the thing I'd like to talk about here cell balance, and the word cell will need to be clarified here because I'd say more than 90% of readers have really never given this any thought. When the battery is made each cell is made pretty accurately to be identical, but unless this is a battery made for NASA some small variances in all the parts can mean that each cell has a slightly different reaction to charge and discharge. Over time these small variations can add up.

The nature of these differences usually is in the resistance each cell has (in the chain of cells in series) and perhaps in its actual capacity for charge and discharge. If left unchecked and unaccounted for inevitably at least one cell starts to get more stress.

The Cell

As you (should) know a 12V battery (as above) is actually a collection of 6 cells (or electro-chemical cells) each which contains some sulfuric acid and some lead plates. This cross section diagram (borrowed and altered from here)


Its tempting to just see this as a black box (well and its often in a black plastic box) but the reality is that each cell may well need individual attention.

In that above cutaway you can see that the battery is a series of  6 cells linked together inside connecting postive to negative to make a 12V battery. By joining two batteries you can make a bigger battery and double the voltage available. An off grider with much nouse would probably find themselves joining 4 12V batteries into a 48V battery, thus reducing the amount of amps that need to be carried to feed their inverter (which makes 240V AC which powers things that plug into the wall).

But returning to my more simple model (having 2 batteries or 12 cells) lets go back to that 0.3V voltage difference.

Once upon a time we had tools to measure the chemistry of each cell, this dates back to a time when (for various reasons) nobody had volt meters. The most common tool was a hydrometer and you can see how its used at this Wikipedia link. You'll notice that in that picture that each "cell" is by itself and has a hatch to allow you to suck up some of the chemistry (sulphuric acid) and measure how much is there.


You may even recall having seen batteries with 6 little caps along the top to allow you to make this measurement. Indeed more expensive and larger batteries usually still have them (see below)




But because less and less people have a clue what to do with these the makers target these to the applications where people should have a clue (and sadly this results in less and less people having a clue).

Lets get back to that 0.3V and work through this a bit more.

Because those little LED meters are cheapies ($2 each) I know they aren't perfect and I know there is about 0.1V difference on one of them (and perhaps something under 0.5V on the other meaning I can't actually see it easily). This means that when I use my Fluke digital volt meter (pretty accurate and provides 2 decimal places) I can see that the voltages are more like 13.18 and 13.38V so that's a bit better.but back on the 8th of the 3rd they were already drifting apart and were 12.91 and 12.89V (which the astute will observe is the other way around).

I noticed that differences were creeping in and so I wanted to observe these more carefully thus I bought those small LED's and fitted them.

  • 14/04/22 I noted 0.1V difference when the batteries were on trickle charge
  • 14/05/22 I noted 0.5V difference when the batteries were on trickle charge

I recently cycled them both down and individually (<<note that point) groomed them back up with a smart charger. Yes, this means I physically dis-connected them (so no more power coming from them if you're off grid) and charged and allowed to settle post removal from the charger. 

Both sat nicely at 13.36V when on the smart charger on "trickle". This is one measurement, but another is what's 'rested' voltage and this was 13.18 and 13.38 ... so this difference now seems to be permanent. 

While this may seem like a small small things may grow.

Is this a problem?

For me, in this situation, no not yet, because (importantly) when the batteries are under load (like when I'm running a vacuum cleaner which draws a lot of power) everything holds up ok and within expectation.

Why is this important?

well we know that the voltage of the battery is 13.18 or 13.38 depending on which we're looking at, what we don't know is what each cell is doing because on these batteries we can't measure that. If we imagine that we could only see the pair of batteries (which importantly is what the inverter or charger sees) we would see 26.56V - its only because we can measure each component we know something is amiss.

But where and by how much?

Lets say only one cell is down and that B1 has one cell that is 0.2V different. 6 of the cells are ideal at 2.23 and one cell is 2.03V ... that means that this cell will now become the weak link in the chain and will suffer more stress and eventually result in the early death of that battery because it is the weaker link.

Important note: a battery is a chain of cells ...

Worse, if I replace B1 then the new battery will be stronger than the then worn B2 (that didn't fail) so that will cause that link to fail sooner too. Meaning I'm minimising the returns on my power from what I spent on the battery.

As it happens (and partly because this is a learning exersize) I paid $90 each for these batteries (they were bought new), but they are, as you can see, small. But then so too is the load and so is the charging. Further I'd say that they are the perfect relationship between needs and cost.

However, f you were in an off-grid house and you were in this situation each battery could well be around $500 and you may have 4 or 8 of them (at least). For instance here is a freinds off grid house 48V system with each "battery" component being a 6V battery (of three 2V cells).


however you can see that each has an inspection cap so you can measure the state of charge and fix up any chemistry. Each of those boxes is nearly a $1000 now, so you can see that caring for and understanding this is crucial for your investment (unless you've got more money than sense).

So ... is there a better way to charge?

Yes, each cell needs to be monitored. However lead acid chemistry is more tolerant of over charging in terms of how it fails, Lithium ION on the other hand is not, and has a nature of catching on fire if over charged and dying (irreversibly) if discharged too deeply. Since Li-ION is expensive and fires inconvenient people have developed a management system for the battery (called a Battery Management System or BMS). This not only monitors the charge but monitors every cell being charged. This is the one out of my scooter still attached to the cells. It manages 13 cells.


As you can imagine with 13 cells in series (compared to just 6 in a regular car battery) the chances of anything getting out of balance is not just high, its practically inevitable (unless you are buying cells that are suitable for NASA). This  BMS not only governs the charge of each cell during charging it it also ensures that if any cell falls below the minimum safe voltage it shuts down the access to power from the pack.

Normally with just 6 cells there is less chance of an imbalance, which is why most small scale solar systems use 12V ... but it of course has inherent limitations in terms of the voltage and therefor the amount of Amps that are required to power much. As you should remember my system actually has 12 cells (6 in each "car" battery) because its 24V and this has no doubt created the situation where somewhere (and we know that its in B1) at least 1 cell is down. This is then going to place more stress on B2 in terms of over voltage charging because the charger only knows the entire voltage of the battery.

Is there something like this for Lead Acid batteries?

Myself I think there is, but its a bit of a fudge (and beyond the scope of this article) so the answer is basically no, and perhaps the "why we don't see things like this in Lead Acid is:

  • Lead Acid is an old technology most commonly used in 12V configurations
  • its perceived as less needed because there is no safety hazzard, and (probably) 
  • because lead acid batteries are very recyclable and rebuildable unlike Li-ION.

Further most companies don't warrant car batteries to be used in Solar Power Systems, so if you kill your battery early then its all on you.

Right now what I see is that its on me to basically prevent this by keeping an eye on the system (and turning off the panel and disconnecting the battery from the Solar Charge Controller) when I'm not in the shed and just let it sit there essentially in storage. Fortunately that's something that Lead Acid is pretty good at.

I'll put it into another blog post for what my solution is on another day (see here for that). Mean time its been a fun ride with my system. I hope you've found this interesting and helpful so far.

Until Next time