Class D amp long term reliability

[dfuller]

I have replaced bad caps in a couple of TVs in the house, but our wall oven has me befuddled. It has been too many years since I was a techie, gotten old, soft, stupid, whatever. I know what board it is, but no visibly bad caps, the door switches are OK, and the relays are working, so some unmarked chip on the board is dead. I may try one more time, but my wife wants new kitchen appliances so I figure it's a losing battle either way (it's been 15~20 years since we got new appliances).

OTOH I have jury-rigged the furnace controller a couple of times since the last time they replaced it. Bad fuses, bad thermistor, and bypassed a cutoff switch that managed to fry itself.

This is why I've largely pivoted towards the "prosumer" level kitchen appliances, there's just less to go wrong in them. Do I sacrifice features? Maybe, but they're features I largely don't need. I don't need Sabbath mode or wi-fi connectivity in my oven.

 

[LTig]

The 00 is used extensively inside laptops. On my bench, like @Doodski said- they are indestructible (but expensive). These are perhaps 15 years old.

View attachment 166524View attachment 166525

Yep, I bought those as well.

 

[thewas]

Many of the phones are repairable, batteries can be changed out, etc. See ifixit.com or other sites that reverse engineer repair manuals for these things, sell the batteries & tools to do said repairs and more (for all kinds of things, washing machines, etc).

As I wrote above though many don't have problems with the hardware but become unusable due to OS updates.

 

[EJ3]

As I wrote above though many don't have problems with the hardware but become unusable due to OS updates.

True, although some problems are from: batteries (either the ones that are replaceable but have a form factor that needs to be found for that particular model of phone or the ones that supposedly cannot be replaced (except by the manufacturer, according to the manufacturer).
And on both ones that the batteries can be replaced easily (or ones that take some level of disassembly to replace the batteries), finding new batteries that will both fit and hold a charge can be an issue.

 

[thewas]

True, although some problems are from: batteries (either the ones that are replaceable but have a form factor that needs to be found for that particular model of phone or the ones that supposedly cannot be replaced (except by the manufacturer, according to the manufacturer).
And on both ones that the batteries can be replaced easily (or ones that take some level of disassembly to replace the batteries), finding new batteries that will both fit and hold a charge can be an issue.

Yes, but after 5-10 years even new batteries can't help as the hardware is too slow and/or incompatible for the current OS and app versions, so you are forced to replace it. Not updating is also usually no option due to the security holes and some apps shutting down the operation of their older versions.

 

[EJ3]

Yes, but after 5-10 years even new batteries can't help as the hardware is too slow and/or incompatible for the current OS and app versions, so you are forced to replace it. Not updating is also usually no option due to the security holes and some apps shutting down the operation of their older versions.

The afore mentioned software may help. but at some point...yes you may have to give up. But if you get 5 to 10 years more than you would have, then you have saved (& possibly invested & made) money to use elsewhere in your life than buying a new phone every phone generation or 2.

 

[paulraphael]

This is why I've largely pivoted towards the "prosumer" level kitchen appliances, there's just less to go wrong in them. Do I sacrifice features? Maybe, but they're features I largely don't need. I don't need Sabbath mode or wi-fi connectivity in my oven.

That's my thinking, too. Unfortunately almost all the appliances are more like consumer quality with pro styling. There a few exceptions (like pro-sumer espresso machines, that are made out of commodity industrial parts, and 3 not-very popular brands of ranges). I talked to a repair guy about refrigerators, and he said they're pretty much all terrible now ... almost scientifically designed to be trouble-free for the warranty period.

 

[paulraphael]

Phones don't strike me as the best analog for audio equipment. So many aspects of the technology are advancing at too rapid a pace for any phone to be a long-term investment.

But you can certainly keep a phone for longer than 2 years. Apple supports its phones for 5+ years, which I think leads the industry. They also make it easy to keep the OS up to date as long as it's supported, which isn't the case with many phones. I kept my 6S about 5 years during which I replaced the battery once. It cost about $60 and took a few hours. The Apple store gave me a loaner phone while they did the work. I'd prefer to be able to pop a new one in myself. But at least for someone living in the same city as one of their stores it's not that inconvenient.

I think 5 years is around the practical limit for all kinds of reasons. For one, even basic cellular tech changes. 3G networks are going offline in the US over the nest 12 months. If you have a 3G-only phone of any kind, it's going to become a relic very soon, for reasons unrelated to the manufacturers. Old phones will also get orphaned by OS updates, including browser updates, so newer web standards will mean more and more sites will be broken on the phone. 3rd party apps will stop supporting the old OS and the old hardware. It's not just planned obsolescence to stop supporting old hardware. It takes lots of work to create backwards compatibility, especially when many of your new features are specifically enabled by hardware advances.

I think it's completely reasonable for a phone to be good for 2 to 4 years. If I buy a phone for $1000, and keep it 3 years, that amounts to a $27/month service. I get my phones with a no-interest loan from Apple. Carrier plans cost significantly more per month. For something that gets so much use every single day, thinking of a phone as a service makes sense to me.

I'm not even taking into account that an old phone still has trade-in value. My iPhone XR was 3 years old and got $200 for it on trade in. My previous 5 year-old 6S got $150 on trade-in. Both phones are probably being used by someone in a far-away land.

 

[dfuller]

That's my thinking, too. Unfortunately almost all the appliances are more like consumer quality with pro styling. There a few exceptions (like pro-sumer espresso machines, that are made out of commodity industrial parts, and 3 not-very popular brands of ranges). I talked to a repair guy about refrigerators, and he said they're pretty much all terrible now ... almost scientifically designed to be trouble-free for the warranty period.

Yeah, fridges are a mess. They're all bad.

As for the ranges and espresso machines... Yep! Even something as consumer as a Breville Dual Boiler is almost entirely standard parts internally other than the computer.

 

[pseudoid]

I had to buy a Philips 00 screw driver

I bought a set of made in Germany Wiha for bench work.

they are indestructible (but expensive). These are perhaps 15 years old.

I had a set of the Wiha version. I guess, based on what uze guyz are saying, the person that stole them from my lab-bench must still be using them.
Then, @restorer-john [errr...] whips out and brags about his teeny-weenie 00 tool.
I believe in the doctrine that "Those with excessive amounts of tools live a long and prosperous life!"

"Do Tools Make the Person or Does the Person Make the Tools?" << I try to indoctrinate the younger crowd by asking this rhetorical question for preaching the above doctrine.

 

[dr0ss]

I recently needed a particular thin-walled hex nut driver to repair a Model-M keyboard; for less than the price of a quality driver I bought instead one of those 120-bits-for-$10 Chinese sets. In the last couple of weeks I've used it for a variety of other jobs, including to repair a dishwasher and tear down three pieces of audio equipment (even though for all these jobs I have much better drivers available). At some point some of the bits will encounter a tough task and fail, but for a non-professional like me spending more than a sawbuck for a tool that I'll use once in a blue moon doesn't make sense.

Back on topic, I recently retired a 1980s Denon receiver which I wasn't able to repair; replacing the blown power transistors didn't do it, at that point it became not a good use of my time to try to diagnose the problem further. Someone who knew more what he was doing could probably have had it running in no time, someone with fewer skills than I have would have tossed it 15 years ago. I think the question of long-term reliability for any product is very much a function of the skill level of the owner (or the owner's friends).

 

[rdenney]

...I think the question of long-term reliability for any product is very much a function of the skill level of the owner (or the owner's friends).

Especially given the scarcity and price of qualified techs for average consumers.

Rick "who just diagnosed and repaired a bad channel in a B&K preamp he just bought" Denney

 

[dshreter]

I just can't make sense of this post. Repairable consumer electronics are not a "hobby".

We had a world where e-waste was a non-issue up until the early 2000s. Stuff sent to landfill was genuinely worn-out, not disposed of for the lack of available spare parts, nor a lack of desire to repair something. Manufacturers were (and still are) required by law to keep a reasonable range of spare parts.

Consumers were simply not inherently wasteful like they are now, 20 years later. A few decades of brainwashing, continual talk of "obsolescence" permeating every facet of technology has sadly normalized the notion of just disposing/buying a new one. Computers are of course the absolute worst for this. People are using machines to browse the internet and send email that are so grossly overpowered for the job and yet they think they "need" an i9 for the job because some stupid salesman told them so.

The current crop of consumers are in my opinion (having spent my life in all facets of sales, from HiFi to houses, fashion to furniture, manufacturing to retailing) the most uneducated, the most unqualified and the most easily persuaded they have ever been. And yet, retailers of all types have forgotten how to actually service and sell to their customers. It's hilarious to watch.

I fix everything in my house where I can. Be it air-conditioner control boards, washing machines, dishwashers, computers, laptops, etc. My neighbour was quoted $1300 to replace his pool water control system as he was told by a "technician" they are not repairable and it's cheaper to get a new one than replace the entire board. It took me perhaps 20 mins to repair and 15 of that was disassembly and re-assembly of the unit. The actual board level repair took 5 minutes and I'd never seen one before- no schematic, nothing. His dishwasher died only the other week and it was another 10 minute repair once diagnosed. Saved him another $1000. It was only 4 years old and he was told "the control board was $300 plus labour etc". Not only did I find a board for $15 online, I suspected it didn't need it (and it didn't). It was just a faulty flood switch.

You make some good points, I guess I'd suggest it's not all one way. I don't conflate audio electronics with something like a washing machine that could be designed for better serviceability without a high compromise. And I agree it's righteous to repair things that can be repaired instead of replacing them.

For audio components though, shoving an entire system into a single box at lower cost in my opinion just makes sense. These products can have long life spans and overall consume less than what I guess you would call more traditional and less integrated components. Having an extra rack with a class AB amp, pre-amp, digital front end, whatever else isn't in some way virtuous when you could have an integrated amp with DSP that lasts 20 years (if you want it to). Traditional electronics can be disposed and upgraded just as easily as any others, so I don't think that solves consumerism.

 

[rdenney]

You make some good points, I guess I'd suggest it's not all one way. I don't conflate audio electronics with something like a washing machine that could be designed for better serviceability without a high compromise. And I agree it's righteous to repair things that can be repaired instead of replacing them.

For audio components though, shoving an entire system into a single box at lower cost in my opinion just makes sense. These products can have long life spans and overall consume less than what I guess you would call more traditional and less integrated components. Having an extra rack with a class AB amp, pre-amp, digital front end, whatever else isn't in some way virtuous when you could have an integrated amp with DSP that lasts 20 years (if you want it to). Traditional electronics can be disposed and upgraded just as easily as any others, so I don't think that solves consumerism.

Not me. Leave the software out of the hardware devices that would otherwise last until they fail. There is no need for an amplifier (or preamp, for that matter) to need replacing until it blows up. I try to segregate software-drive devices as much as possible so I don't have to replace expensive hardware. For example, there is nothing about a sound-system amplifier (and these are not cheap) that needs to be tied to a software lifecycle.

Rick "even preferring a separately replaceable module for DSP" Denney

 

[restorer-john]

Rick "even preferring a separately replaceable module for DSP" Denney

That's how it was when DSP was first released to HiFi aficionados. Yamaha brought the DSP-1 to market in 1985 and it was a self contained DSP processor (for sound field recreation, effects etc), with 2/4 input, 6 out. You needed a separate MVS-1 (master volume- 6 channel) and six power amplifier channels. It cost about AU$1599 here, so expensive, considering you'd want a pile of power amps too.

Their early efforts meant I owned several DSP processors over a few year period, and I still have all the amplifiers as you could use their dedicated 2/4 channel ones or any power amps you might have.

When DD came along, Sony, Yamaha etc all sold separate DD processors so people could upgrade their system. Big AVRs with on-board processing at cheap prices started to take over in about 1991-93.

 

[dr0ss]

Leave the software out of the hardware devices that would otherwise last until they fail.

Also the LED and LCD screens. Give me a good knob or dial any day.

 

[Raindog123]

Give me a good knob or dial any day

How about remotely-controlled servo knob or dial?

 

[dr0ss]

How about remotely-controlled servo knob or dial?

Our main system uses a NAD 1700 Tuner/Preamp with remote-controlled motorized volume. Over 30 years old, and I don't see why it can't run for another 30 years. The knob has been sticking a bit lately, but I expect 10 minutes of clean and lube will fix that right up.

 

[001]

"Do Tools Make the Person or Does the Person Make the Tools?"

And, depending on the wisdom of the tool-wielder, the 3rd option = "Or is the Person the Tool?"

 

[Doodski]

That's how it was when DSP was first released to HiFi aficionados. Yamaha brought the DSP-1 to market in 1985 and it was a self contained DSP processor (for sound field recreation, effects etc), with 2/4 input, 6 out. You needed a separate MVS-1 (master volume- 6 channel) and six power amplifier channels. It cost about AU$1599 here, so expensive, considering you'd want a pile of power amps too.

Their early efforts meant I owned several DSP processors over a few year period, and I still have all the amplifiers as you could use their dedicated 2/4 channel ones or any power amps you might have.

When DD came along, Sony, Yamaha etc all sold separate DD processors so people could upgrade their system. Big AVRs with on-board processing at cheap prices started to take over in about 1991-93.

I sold those Yamahas that you mention. Great sellers. There was also the Sony TA-E1000ESD too. We had that baby in stock and people did not know what to think of it because it was basic surround sound and was so fancy. Anyway we set it up and voila they started selling. It had that amazing DSP EQ that nobody else had. It took a very serious buyer to purchase one of them back in the day. It was gorgeous.