PostNL relabels approximately all parcels addressed to me (I almost always have to change either the delivery date or location to one convenient to me), completely free of charge.
Free of charge to you and free of charge to the sender. Which is exactly my point, for PostNL it is a sunk cost and if that will happen for significant amount of their consignments it would be an issue.
The term at which burden of proof shifts from the retailer to the consumer has been raised to 1 year in the EU (maybe not in the UK due to Brexit). As this is a matter of civil law, the standard of proof is also "more likely than not" proof, not "beyond reasonable doubt". You don't necessarily need an expert opinion, it _can_ be sufficient to collect a bunch of reports of similar failures.
This is not true. You have the right to a "deugdelijk product" (good product) for the entire expected lifespan of the product, and if it breaks in that, they do have to fix it (or provide a comparable replacement).
If, however, for whatever reason you don't want that, you can't demand all your money back, but only 50%. That's only if you agree to the money though, the seller can't unilaterally choose to give you 50% back instead of repairing it.
Note that this table comes from "Techniek Nederland", which is a business association of (among others) technical retailers. They've an interest in lowering the expected lifespan of appliances, as that means their members have less warranty to provide. They actually note (probably for legal reasons) along with their table that it contains average usage, not expected lifespan (i.e. how long people use things before they replace it, as opposed to how long you could use it before it breaks).
Courts will, and have in the past, throw this table out, if you make a reasonable argument why you could expect a longer lifespan.
It was linked from the ACM or consumentenbond, or some such consumer website. I don't have the tab open, but it wasn't just a random link from Google.
But yeah, it's just a guideline like I said. Some people here are throwing out numbers such as a "15 years" or "decades" with no qualifiers, and I'm not sure if that's reasonable for a €230 oven (cheapest in a quick check).
Aside on retailers: I haven't worked in a store in 15 years, but back then a lot of manufacturers just said "lol fuck you" when you tried to claim warranty above their stated warranty period. It was typically up to the retailers to bear the costs. One (of several) reason we left the consumer business: it's hard to compete as a small independent store for many different reasons, and this just made it that much harder. You can't spread out the costs, and you have almost no leverage against Asus or HP.
In short, at least back then the manufacturers could just keep shipping wank without really suffering too much damage to their bottom line, and the retailers with essentially no power to change anything were getting screwed. I don't know if that's changed, but probably not.
> It was linked from the ACM or consumentenbond, or some such consumer website. I don't have the tab open, but it wasn't just a random link from Google.
Yes, it gets often quoted, but things don't become true by being often repeated. It probably wasn't the Consumentenbond, as they actively call out the list from Techniek Nederland (previously Uneto-VNI) as being too short on their website.
2 years is the EU-wide minimum, individual countries can raise that bar. The Netherlands for example has the same reasonable expectation rule as discussed in the article. You absolutely will win a similar court case here (I know people who've done it).
How much of that cost is related to the physical handling of the panels themselves, and not the electrical installation, though? Weight reduction isn't going to help there.
It’s propagates through the supply chain, loading, logistics, wear on vehicle transport etc.
We should practically get to the point where someone can buy a roll of material at Home Depot and unravel it on their roof, nail it, and plug it in themselves.
The currents and voltages involved are going to make that a non-starter. Do you really want random people messing with those? The solar inverters are also sized that big for a reason.
At least in countries with strong regulations around working with electricity this is simply not going to be feasible.
I've been in the PV business for some time now and seen a person get killed by it. It's not pretty. Still remembering that smell of burnt flesh... Now, to be fair, that was at a 12MW-installation, not on a roof. But still...
> The currents and voltages involved are going to make that a non-starter. Do you really want random people messing with those?
As part of our daily lives, a great many of us climb into a steel box powered by explosions and packing a 20 gallon container of flammable liquids (and increasingly several hundred pounds of also flammable batteries containing more electricity than an average family uses in a week) and then pilot that box at 80Mph down a strip of concrete packed with other large high-speed objects containing flammable liquids. Occasionally, we run low on flammable liquids in our high-speed metal box and get to refill the flammable liquid container ourselves at a flammable liquids depot, which contains upwards of 40,000 gallons of the flammable liquid delivered by other larger high-speed metal boxes which also share the same strip of concrete with us.
So: I'd expect some product safety iteration here before we get to the "roll out your own solar panels", but no, I don't consider that a non-starter.
But you can see fuel. You can't see currents and it's not trivially visible which things you can touch at all, which things you can touch at the same time, which protection to wear, how to deal with the potentially fatal flashing arcs, ...
PV installations on roofs typically have around 10-20kW peak output.
Let's go with 10kW. That's around 25 panels, each outputting 30V with something like 13A. Small installations are typically single-stringed, so you end up with a voltage of 25*30V=750V with 13A DC. That's pretty likely to kill you within milliseconds if you mess up.
There's a reason that stuff tends to be handled by professionals. It's a ridiculous (and pointless) risk if you aren't well educated about it and have some experience.
You could probably make a system sockets that communicate with each other before exchanging any serious power. You could digitally sign cables, and add shielding to make them detect cuts..
I'm not saying it's a future we should want :)
But isn't that kind of how super chargers work?
Of course, until all our grid hook ups are smart, we'll probably need electricians at some point.
Enphase systems work as you describe. Each panel has its own AC inverter, and they from a mesh network and run sanity checks for shorts, etc. before exporting power.
There are lots of boxes in our house that do 16 amps at 120V. Some do 240V, and some do higher than that, and some of those are next to sinks or in high-humidity environments. The voltages and currents for solar panels (especially if you use 240V microinverters) don't seem like a non-starter to me.
That's AC. The panels are DC. That makes a big difference.
That said, the point of "do it yourself" is that you'd nake it less dangerous for ordinarily folk. So the risk of shocks would come down.
What would concern me more is long-term fire risk. If not installed correctly, with the right spec parts etc, proper grounding etc, there's a significant risk of fire. Not immediately perhaps, but a couple years down the road.
Again DIY kits would need to be designed with this in mind.
> That's AC. The panels are DC. That makes a big difference
What's the qualitative difference between 16 amps at 120V and PH
v DC? Either is enough to kill a person if mishandled, and yet Home Depot sells breaker boxes over the counter.
750 volts will not kill you in single-digit milliseconds, but rather hundreds of milliseconds (or not at all), and it's probably worth it to run the extra wire to not be single-stringed
To be fair, it didn’t start that way and there are decades of design, legislation and safety regulations around all this, along with infrastructure for licensing/certifying capabilities, tracking and policing capabilities and mistakes over time, insurance, yada yada.
And you know how much mockery Oregon and New Jersey get, for believing gasoline is so heinously dangerous as to require trained dispenser operators? Meanwhile the rest of us just pump it into our own cars like adults.
It's funny to look at electricity from the same perspective.
It has nothing to do with safety. It's pure protectionism. The point is to keep small gas stations competitive by imposing labor costs on larger gas stations.
Friendly Neighborhood Handyman checking in here. Average Home Depot customer? Absolutely not unless there's some plan to quadruple suburban emergency services budgets. On the other hand I get pretty tired of sneaking around local restrictions on electrical work. Residential electrical work isn't exactly complex and I can't devote a couple years to working as someone else's laborer to get a cert. I'm perfectly capable of handling 100% of a residential solar install (including battery backup) and it's aggravating af to have to go find an electrician to bribe to get permits and inspections.
My work meets or exceeds code requirements, every project, every time. If I encounter anything where I don't already have relevant code committed to memory I stop what I'm doing and go look it up. How many tradesmen do you know that can say the same with a straight face? Anyway I'm fine with pulling permits and having my work inspected, I prefer it even when possible.
Around here you can buy a permit if you’re a homeowner. You then have to set up the inspections and actually do all the work properly, but there are no restrictions like that. The inspecting agency publishes documentation about what to read and common pitfalls even.
I can pull my own permits for carpentry and masonry work, structural stuff, but that's about it, and only for my personal residence. Homeowners here are barred from systems work of any kind, and it takes a contractor's license to pull permits when working on someone else's home.
I see how you'd think that but it isn't the case. Where I live only licensed electricians are allowed to do any work more involved than changing a light fixture. As an example I've got a 1600 square foot detached shop on property I recently purchased. There isn't six inches of wiring in the entire building that is up to code. My options are ignore it and risk a fire or electrocution, spend >$15,000 to get the building rewired, or spend $3,000 on materials and risk a life-altering fine and/or jailtime if I get caught fixing it myself.
I'd be satisfied if I could simply sit the licensure exam and maybe have to pay extra to do some kind of practical demonstration. Local requirements for residential licensure include documented multi-year experience as an electrician's helper before you can even apply to take the exam.
Ironically batteries is what makes it feasible - I can dump excess into battery instead of paying 3x more for install so I get hooked up to grid in a certified way.
Jay Leno talks about installing solar on his house (which he did himself) and commenting that he was getting shocked a lot, bc as soon as the PVs are in the sun, they're making electricity. He said it made handling the units tricky.
I installed an additional 12 505Wp panels by myself last weekend, the panels came with MC4 connectors installed which is pretty standard I think. Hard to get zapped by solar DC juice that way.
BTW: installing solar panels DIY is apparently super easy, as I found out. I have a flat roof and used micro inverters, to make it easier, but I was done in less than a day (excluding selecting the components and layout)
A small current is going to flow internally, but nothing else happens. It's quite normal to have solar panels running with zero load in regions with lots of PV - reason being, that the carriers need to keep their electricity nets stable and have to carefully balance electricity entering and leaving the net.
At least in Germany, every PV installation of certain size (> 30kW peak) is mandated to be able to be shutdown remotely by the carrier if you supply electricity for the net and aren't just using it for yourself. (You get paid the same during shutdowns, just like it were running. Otherwise it would be quite damaging and likely reduce adoption of PV)
Point being: no, it doesn't hurt the panels and is a regular ocurence.
The generated power will be dissipated through the panel as heat, AFAIK.
Which means that in winter, probably nothing, because it's cold, but on a hot summer day with peak sun, the heat might start damaging the cells. How much exactly you'd have to look at studies.
My guess is the output will permanently degrade by a few % per year if the panel is not connected. Might go down to 80% way quicker than normal (25-yr)
> The generated power will be dissipated through the panel as heat, AFAIK.
Solar panels are not constant-power devices. In an open circuit, they will generate their open circuit voltage at nearly zero current (except minor internal leakage), and thus nearly zero power. In a short circuit, they will generate nearly zero voltage, and thus also nearly zero power. To get maximum power out of a solar panel requires maximum power-point tracking (MPPT), where the load is adjusted such that the product of voltage and current (that is, power) is optimized for the current conditions; while significant power can be delivered to a fixed load, there's no real power being generated without a load.
The thermal power of the sun will heat the panel, to the extent that it is not reflected. But no electrical power (or any power) is being "generated" by the panel, the panel is just absorbing photons like anything else with low albedo.
That's just nitpicking. There is thermal power generated from the electromagnetic power from the sun and GP is right that a solar panel turned off will be hotter than one turned on.
And if that was the original poster's intent, I apologize for nitpicking. My impression was that the use of "generating power" in the given (open circuit) context suggested a fundamental misunderstanding of the behavior of solar cells in this situation on behalf of the poster, and thought I might clarify; and perhaps even if the original poster understood this already, someone else learned something.
Think of what happens to a normal roof tile in the sun: it absorbs solar energy as heat and also reflects some and radiates some away. A solar panel is the same (though a bit more reflective), but when a load is connected some of the solar energy is converted to current instead of being absorbed as heat. Therefore the panel is a little cooler when a load is applied.
There is no power. Power is IV, current times voltage. The voltage will be the rated voltage of the panel at that sunlight level, but the current is 0 (minus some very, very small (microamp) internal currents).
Alternately, power can be expressed as V^2/R. But in an open circuit R is infinite, so again, zero power.
There is ~1000W/M2 of electromagnetic power from the sun, and if it's not turned into electrical power it will be turned into thermal power, thus heating up the panel.
But as noted by sibling comment, that heated panel will then begin to transfer that heat back into its environment, as a function of its temperature difference with its environment.
So as long as manufacturers engineer their panels to be tolerant of the maximum heat at a site (i.e. full sun, maximum temperature), the panels won't be harmed in any meaningful way. They'll just heat up a bit faster than if they were providing current.
Is ther a difference between "electromagnetic power" and "thermal power" here? If a panel is not connected, there is no conversion and the surface is warmed - just like any other surface exposed to the sun gets warmed.
PV panels are just like charged capacitor or a chemical battery with no loads: just holding unused potential differences with no damage to the unit.
Or have interconnecting cables, plugs, and sockets that are designed to prevent you from touching the conductors. Yeah you could probably still shock yourself but you'd bascially have to be trying to do it.
if it were really a problem moving forward and diy becomes the norm(which i doubt is the case) it's pretty trivial to apply an opaque sticker or cardboard covering to the panel during manufacture.
They're limited to pretty small sizes by german law - they are so insignificant that they're much less dangerous to handle. I'm not up to date on their ROI, but IIR they usually were a rather bad investment and more of a novel toy than a serious and reliable source of electricity.
Essentially, any notable installation fundamentally deals with much higher currents and voltages and as such is much, much more dangerous. Once a certain size is reached, the carrier also has to be involved and professional installation is mandatory, both due to the law and requirements by insurance companies.
At least here in germany. I've been involved with building all kinds of PV installations in bavaria, from 4kwp up to 20MWp. The balkony generators aren't taken seriously by anybody in the industry right now, at least.
> At least here in germany. I've been involved with building all kinds of PV installations in bavaria, from 4kwp up to 20MWp. The balkony generators aren't taken seriously by anybody in the industry right now, at least.
If you're working at that size, I'd expect you to ignore balcony systems regardless of how cost-effective they were.
My point here is simply and only that it's possible to make a system safe enough that an untrained and unskilled member of the general public can just plug it in and use it, which is exactly what was being called for up-thread with this:
> We should practically get to the point where someone can buy a roll of material at Home Depot and unravel it on their roof, nail it, and plug it in themselves.
Germany basically has that (even if it's not in the form of a roll); there's nothing fundamental preventing the USA from having it too.
They're sold for apartments, and as DIY jobs. They're designed to fit on a balcony just about wide enough to stand on, and to be installed without needing an expert.
The point of the example is to show that you don't need an expert. It's not even trying to show a specific unit that suits all people, just that one thing, that you don't need an expert to install it.
The voltages are the same regardless, because that's how domestic electricity works. (If you forced me to guess, I'd expect grid-scale PV farms to go direct to a higher voltage than domestic users, but I'm not an electrical engineer).
The law in Germany may prevent you hooking up ten, but that's not relevant to the point or the market.
Can Americans even hook up things this size on their rental apartment balconies?
> Plus without proper meter (or CT "limiter")
Difficult term to search for, so I'm unsure what that is exactly. I get links about inverters, and I'm sure you noticed this comes with one so it's probably not that.
And this relates to the impact of module mass on (supposedly) preventing DIY installation (despite my example of a DIY installable system) how exactly?
Homeowners work with 240v and tens of amps all the time across the country. Hell I wired a hot tub breaker panel and a car charger. Safe enough interlocks and it's a non issue
I would rather be zapped with a 240v AC current vs 240v DC current.
AC power crosses the zero line twice per cycle while DC does not. AC has a lower ‘let-go’ threshold, but DC contracts your muscles and makes it harder to let go.
You are correct though, if you de-energize your panelboard and have a deadfront cover over the line side conductors and lugs, working inside a panelboard (or on electrical wiring) is safe.
DC interferes with your heart's rhythm much, much less though, due to being constant. AC's frequency easily causes ventricular fibrillations even at low currents and voltages. AC is considered potentially lethal starting at 50V. For DC it's 120V, because it's significantly easier on your heart.
It’s the amperage that kills you, not the voltage. 5000VAC at a 1.0 nano amps is not going to be something you can feel, not even as something like static electricity.
We're talking about proper sources here where the voltage doesn't disappear as soon as you start mildly conducting. So volts and amps will be proportional in this context.
I don’t buy that the volts and amps will always be proportional. In my experience, the volts are usually pretty fixed, depending on the circumstances. Like 120VAC in most homes in the U.S., but variable amps — 15, 20, 30, 50, 100, etc…. Or 240VAC in Europe and certain other places around the world.
And if you want to talk about power lines, then the neighborhood medium voltage lines are going to be roughly the same in most places within the same jurisdictions, and distinct from the true high voltage lines that are used for long distance transmissions.
You are not conductive enough to get anywhere near 10% of the circuit's capacity. Therefore, the supply might as well be an infinite amp supply. You, in any particular situation, act as a particular ohm resistor. The amps that flow through you from mains voltage or big solar arrays will be directly proportional to the volts.
If a 120V 15A supply puts 50mA through you, then a 120V 100A supply will also put 50mA through you.
A supply that's "5000VAC at a 1.0 nano amps" really means that it starts at 5000 volts but super rapidly drops to zero volts as it conducts. A household supply is going to have negligible voltage drop by the time it turns deadly.
Edit: The other way to put it is that 99.9% of supplies don't give you a certain number of volts and amps. They give you a certain number of volts and they have an amp limit. If you're not approaching the amp limit then the only thing that matters is the volts.
I get what you're saying, amps are pulled, not pushed. But you should consider ohms law. Hand to foot, with a dry hand, typically is 400ohms. You can pull a lot of amps through 400 ohms if the voltage is high enough
The focus here is the 30-750 volt range with tens of amps, with a secondary mention of neighborhood power lines. For injury purposes, we can treat all of these as having unlimited amps available. By the time there's enough kilowatts going through your body to notice the curve shifting, we're well past the point of wondering whether or not you die.
My point is that the number of amps you can get from the circuit is irrelevant, it's "more than enough" and that's all you need to know beyond the voltage and the exact way the human is being exposed.
And houses are burning and people are being electrocuted regularly - being not only a hazard for themselves but also their entire neighbourhood. I certainly wouldn't want to live next to somebody who thinks they can handle their electricity installation by themselves.
for an offgrid installation it's feasable to possible to have an idiot proof system. It rise the cost, but I don't see why it would be impossible. I actually saw one at a store (not for roof but anyway).
> There's enough energy in a Tesla battery to for the Tesla to reach escape velocity.
No, it's not even remotely close. A Model S weighs around 2000kg and has a battery of 100 kWh. That's √((100 kWh)/(1/2*2000kg)) = 600m/s of delta-v. Escape velocity for Earth is 11.2km/s, almost a factor 20 more.
This nerd sniped me a LOT, I’m wondering if it’s possible for a chemical battery to reach orbital velocity (not escape).
An idealized Tesla would just be its battery (500kg) perfectly dumping energy to mechanical forward speed. Cutting 3/4 of the weight gets you closer to the delta-v you need, but youre still off by a factor of 5. Though orbital velocity, and leaving from the equator and gaining that speed, means you only need to get up to ~7.2 km/s. Still only a third of the way there.
Maybe you could split your battery into chunks, and expel them once they’re expended?
I feel like the author conflates tolerance in component value choice and fabrication tolerance. The E-series were chosen so that if you have perfect resistors (no fabrication tolerance) of only their values available, you can replace any resistor value you need with one from the series, and you'll never be more off than a fixed error (e.g. 20% for the E6 series).
This only works with perfect resistors, though. If your actual resistors have a fabrication tolerance, you might be more off. For example, if you need a 41 Ohm resistor, you can use a perfect 47 Ohm resistor from the E6-series, and you'll be within 20% error. However, if that 47 Ohm resistor has a 10% fabrication tolerance, in reality it might be 51 Ohm, and that's more than 20% off from the 41 Ohm you needed.
To take the example from the author's last paragraph, if you need a 70 Ohm resistor, the idea is not that you could be lucky and find an exact 70 Ohm in your E24 resistor set, but that you change the design to use a 68 Ohm instead, and don't introduce more than 5% off by doing so (regardless of the resistor value you needed).
I didn't understand the Renard Numbers tangent until realizing it's the same principle of exploiting "usage tolerance": He replaced the 400 different cable lengths with 17 "standard" cables that can be stretched to any of the desired actual lengths.
The choice of numbers ensures that the "stretch", i.e. error never exceeds a certain factor.
Thin-film resistor design engineer here! It's dependent on value and geometry -- if you order a 0.5 ohm resistor the meters on our trimming lasers only go down to 20 mΩ and you're getting a 5% part at best.
And that's why the really precise resistors are so damn expensive. E.g. VPG makes a 10k 1/5W 0.001% tolerance ±0.2ppm/°C, but they're $116 each with a minimum order quantity of 25 on DigiKey (so $2900 minimum purchase). They've got a really expensive meter for their trimming setup!
I'm not as familiar with foil resistors, but if you apply the same rules as thin film I would expect that you could trim this with a normal meter (the ± is 0.1 ohms) and the major cost driver is laser trim time and the space cost of some extra geometry on the resistor to support the tight tolerance (i.e. more fine trim features than standard).
I believe Vishay's ±0.2ppm/°C TCR is a materials science process specific to one of the companies they own, so that is also a reason they can charge quite high prices.
If you don't need that kind of TCR (i.e. your part is not going to space) the price should go down considerably for a thin film NiCr resistor (5 ppm - 25 ppm). There is actually a lot more direct sales and custom design volume than I would have expected when I started in this industry, so what you see on Digi-Key is not the entire market.
As both a sound and electrical engineer I think most high end audio electronics is bullshit.
If you know what you're doing a 50 cent opamp will give you results that are beyond what a human could identify in a double-randomized blind test. Same goes for comparing two rusty pieces of wire against highly pure copper speaker cables.
For some reason audiophiles will use darn massive gold (or silver) RCA connectors instead of something like a balanced connection that would actually make sense.
For audio applications 1% resistors are fine. You can use still affordable 0.1% in places where you truly care. Below that it is getting ridiculous, as the influence of harder to match things will take over. Things like speakers or the room they are placed in. How about the speed of sound changing with air temperature and humidity? You better have a room that has uniform and stabilized air temperature and humidity.
A big part of the audiophile game is about psychological impact and the joy of personalized optimization. I spent a lot of money on audio equipment and a lot of time on researching it myself. It is an interesting thing. But in the end it is also physics that are interpreted by your brain and I can't help but feel bad for people who need to (incoming hyperbole) turn every part of their setup into gold in order to be able to enjoy listening to their equipment as music passes through it.
> For some reason audiophiles will use darn massive gold (or silver) RCA connectors instead of something like a balanced connection that would actually make sense.
Is there a reason why they don't just use digital audio everywhere and convert to analog as late as possible? Inside the speakers for example? I mean, digital audio is pretty much perfect. Why are analog audio signals still a thing? People actually pay thousands of dollars for magical analog audio cables and it boggles my mind.
Good question, this is what most modern studio engineers would do, especially given that more and more speakers (like the Neumann KH120 II) feature internal FIR filters so you can calibrate them using measurement microphones.
Many modern Studios run some form of digital audio network as well (Dante, Ravenna, etc) so you can go digital as early and close to the source as possible and do all the routing using network switches and some sort of managment software (e.g. Dante Domain Manager). So if you do that it makes sense to go digital all the way to the speakers and convert directly to analog there after running through a DSP that allows you to correct for the speakers position in the room.
Cables can matter. But more for mechanical reliability, good shielding and perfect handling after years of use than any other magical properties. If you want to run balanced audio signals at miniscule loss for a few thousand meters it turns out that you can just use CAT6 for that. These cable are made for far more challenging (speak: higher frequency) signals and they have a track record of working.
My speakers convert digital to analog. They have ethernet jacks in the back. Maybe you bought the wrong speakers?
Stepping back for a moment… you see digital interconnects in high-end pro audio gear, using systems like Dante. These systems are NOT simple. When you have multiple digital audio systems connected together, you have to worry about whether they are all running from the same clock, or whether you can convert from one clock to another. Systems like AES solved this by having “word clock” running on separate coax cables with BNC connectors.
If you look at consumer digital audio stuff, like Bluetooth speakers, you find all sorts of weird problems. It turns out that for cheap consumer gear, you get better quality audio from simple analog connections anyway.
If you want speakers with digital inputs, you also need to power those speakers. That uses up more power outlets.
Right and isn't it the case that good quality D/A-converters still cost much money. So if you want every speaker to have them, and you want many speakers to get an immersive sound then "digital loudspeakers" can become expensive?
There are a lot of different parts involved—D/A converters, crossover networks, and amplifiers. Back in the day, good D/A converters were expensive, but they have gotten really cheap. If you have amplifiers that are cheap enough, you can put them after the crossover network and save money on the crossover network. If you have D/A converters that are cheap enough, you can eliminate the crossover network entirely and do it in DSP.
At that point you are comparing the cost of one more channel of D/A against the cost of an electronic crossover. It’s super easy to just buy a D/A with more channels. If you get to completely eliminate an analog crossover network, maybe that’s a win in terms of BOM cost.
It can be. But standard Bluetooth connections for audio can be terrible. Streaming from the internet, that is digital, and there can be delays and gaps in the sound.
By "perfect" I just meant that digital audio perfectly reproduces the recorded analog signals. https://youtu.be/cIQ9IXSUzuM
I didn't mean to indirectly praise Bluetooth in my post. Bluetooth anything pretty much sucks. Bluetooth audio in particular is pretty bad and full of usability issues. It doesn't seem to have the bandwidth required since the audio gets transcoded to some lossy format.
I once set up an mpd music server on my local network and audio quality was perfect. However I encountered significant latency issues. Play and pause had a latency of one second which made it unusable. That was true even for uncompressed audio streams over the network.
I got bored before I was able to resolve the problem. Maybe the problem was my network. I should try it again now that I have a much higher performance router running OpenWRT which is capable of traffic shaping.
Not much reason to use aggressive compression when wires have many orders of magnitude more bandwidth than bluetooth. And inconsistent latency is also not an issue when you control the whole network & don't need to share it with anyone else.
> For some reason audiophiles will use darn massive gold (or silver) RCA connectors instead of something like a balanced connection that would actually make sense.
It's hard to find XLR (or even TRS) balanced connectors on most non-professional (=TV studios, expensive conference room setups, DJs/clubs/similar venues) equipment.
Yeah, but I wonder why? Sure, a Extron DMP with 128 bit DSp processing and 8 channels of balanced in and 12 channels of balanced out would qualify as professional conference equipment. But at a cost of approx 2.8 grand it is cheaper per channel than most audiophile equipment you can find.
The truth is that we sound engineers who use that stuff for work often do not have the luxury of caring for things that don't matter to the process or the outcome.
Professional AV equipment is expensive because it needs to be reliable on top of sounding as if it wasn't there, one of those units described above was running without fault for 15 years 24/7 in a room that was 30°C each summer (and it still works). Meanwhile my brother bought a silver RCA connector that broke off after a year of use — tip stuck in the amp, guess who had to fix it..
Even a 80 Euro Berhinger USB audio interface has balanced outs nowadays.
I think this is more of a cultural divide than anything, with tradition being a big part of it. In the olden days balanced I/O had to be done using specialized transformers. Unless you got really expensive well wound ones these could degrade your signal significantly — that might've contributed to a bad rep in audiophile circles. But today you can balance or unbalance electronically with indistinguishable fidelity and... ironically a lot of the analog "warmth" people love in old recordings came from the transformer on the inputs of old mixing desks.
There is really no reason to use unbalanced today other than being really pressed for money or running so short cables that it won't matter - and even then you could do better than RCA connectors.
> Even a 80 Euro Berhinger USB audio interface has balanced outs nowadays.
Yeah but who outside of people already interested in DJing buys that kind of stuff. It just looks ugly, unlike your classic home theater setup.
Out of "looks decent (=passes the Spouse Acceptance Factor test)", "reasonably affordable" and "has decent quality", choose two... unless you got a partner accepting you literally putting up a 2m truss with lasers, movingheads and a strobe in your living room that could compete with a mid-range disco, and a 1.200W fogger on the ground. I'm lucky enough to have such a partner, but I'd say about 99% of people don't.
There's something to it that the equipment should look beautiful in your living room, Bang and Olofssen -style. Music is beautiful, equipment playing it should be too. Or at least it enhances the experience.
Yeah it is a cheap mobile usb interface. Beauty is not the name of the game there — which is why I used it to argue against balanced being a feature of expensive equipment.
Balanced outputs have nothing to do with the aesthetics of the object. And I choose option 4 — build it yourself — then it can be done cheap and look however decent, massive, invisible, ridiculous or whatever the aesthetical ven diagram between your second half and you looks like. And it can have balanced I/O if needed ; )
What about shunt resistors? I can pretty easily get a 1% 5mΩ resistor, but they don't look to me like they are constructed in the same way as a generic resistor.
AFAIK, it used to be that parts binning was used to sort parts by tolerance. So the 5% bin wouldn't include <1% parts because those were already selected into the 1% bin in the factory and so on. Is it still like this?
Mostly, no. Nobody except for expensive precision resistor companies are actually measuring resistors more than statistically.
The resistors are manufactured so that they are "guaranteed by manufacturing" such that the outliers are 1%, 5%, 10%, etc. And they do statistical checks on batches, but not really looking for the 10% outlier (which is stupendously rare and very difficult to catch) but looking for slight drifts off nominal (which are much easier to spot) which would result in more outliers than expected.
As such, if you measure resistors, you tend to find that you get really close to nominal--much closer than you would expect for 10%, say. Resistors are so cheap that binning simply doesn't make economic sense.
Is this how LEDs are binned as well, or are they powering each node on the wafer before packaging? They're orders of magnitude more expensive than resistors, so I figure they might...
There are all kinds of crazy parameter variations in optoelectronics. I understand that resistors are really close to nominal because the manufacturer's ability to tune the process controls are so much better than the standard 5% and 10% bins, but it seems that LED manufacturing is way more difficult and they can't always tune the process to get exactly what they want.
I saw a video from the WS2812 factory and from what I remember all of the LEDs were tested individually on the die before assembly. I don’t know if that’s typical but those are pretty cheap for what they are.
They should still bin, so that each individual resistor gets the highest price possible by the virtue of its classification, even if the binning is costly.
Not if the additional cost is more than the additional revenue.
Let's assume that without binning you get 20% over cost of manufacturing. If it costs 5% more to bin-check all resistors, and you wind up selling 1% of them for an additional 100% mark-up:
No bin Bin
Cost to mfg: $ 1.00 $ 1.00
Cost to bin: .05
------ ------
Total cost $ 1.00 $ 1.05
Base price $ 1.20 $ 1.188 (99% sold at base)
Premium price 0.00 $ 0.022 (1% sold at un-binned cost x 2.2)
------ ------
Total revenue $ 1.20 $ 1.21
====== ======
Profit $ 0.20 $ 0.16
It depends on the component and the company/process. Laser trim time for thin film is a significant cost-driver, so if possible you want to aim for a specific value and reject or bin-sort the rest out. My company only makes 1% tolerance resistors by laser trimming.
you can't always bin a ±5% resistor as a ±1% resistor if its value tests within ±1%, because, as i understand it, a ±1% resistor often needs to be ±1% over its temperature range, working voltage range, and lifetime, so it has to be made differently than a ±5% resistor
if your temperature range is -40° to 85° and your resistance is +0.9% off nominal when measured at 22°, your temperature coefficient of resistance would need to be under +16 ppm/° to ensure that it was still below 1% even at 85°. a more typical tcr for ±5% thick-film resistors is +250ppm/° (see, e.g., https://www.vishay.com/docs/51058/d2to35.pdf) and so there is no hope of binning such a resistor as a 1% one
aging is another source of component value error that can prevent binning (the component value drifts over time, usually proportional to the square root of its age), and some kinds of resistors also have a significant voltage coefficient of resistance (mostly semiconductor types like carbon-film and the antediluvian carbon composition)
these phenomena sometimes lead designers to use expensive tight-tolerance resistors (±0.01% nowadays, 50¢–250¢ each) even in circuits that can easily be calibrated to handle component value error, just to keep the calibration from going off due to temperature or aging and to improve linearity
disclaimer: i'm not an electrical engineer, i just play one in ngspice
It blows my mind that this wasn’t more widely publicized over the years. At least this is the first time I’ve seen it, and I learned vim a long time ago. Partly because if it was a choice between weird keys, may as well learn vim.
It blows my mind how many people need directed at the included documentation or config files.
Sheep to slaughter. Before anyone judges me for judging, instructions-included is pretty consistent across disciplines.
I'm not a mechanic but I can figure out routine maintenance/customization.
I'm surprised you, and surely others, arrived at switching editors instead of changing the editor itself. Not in the source or with compilation. The configuration.
I know you say partly, I just doubt there is any perfect editor. All roads lead to configuration.
That was only one of the reasons. The keybindings were the seed of the idea, but as soon I started thinking about what I would like to change, I realized that I also wanted multiple edit buffers and a directory browser. Essentially it's my all-in-one coding environment.
