Modern micro amps - disposable?

[AlexanderB]

I saw a brand new QSC class d amp (couldn't say what model it was/if it was usa made or not) not even have 2 months of use before it blew (literally it popped and started smoking) and was beyond repair. I really don't care how my comment rings with your experience, the fact remains that amp blew up for no apparent reason. just because you have had a good experience doesn't discredit my bad experience Im not trashing QSC, as i stated earlier i own a RMX and i love it, bought it used for a steal and haven't had a single issue with it. I don't like or trust class d circuitry, when it fails its catastrophic and can't be repaired....so i agree with the OP, Class D (d is for disposable)

Maybe it has changed, but up til recently, the only class-D amplifier in the QSC portfolio is/was the PL380. All others were class-A/B or class-H.
And although I had one of my PLX2 amps fail (a 2502, which is class H + SMPS), it was a mechanical failure. One of the aluminum legs on a electrolyte capacitors in the SMPS had snapped off during shipping (to me). Fortunately, that was one of the easiest repairs I have done in any audio device, ever!

If I remeber correctly, there were some issues with the original generation PLX amps, where some key component would fail, with dramatic consequences.

That said, I share some of your concerns regarding "down-sizing", but more related to the aftermarket capabilities than to the actual concept itself.

 

[CrUiSeR]

For the most common products in the line, the labor charge is only $75 including all parts except tubes and power module, and in all of last year I only replaced 2 power modules. I don't see how this is uneconomical for a repair?
.

That is very reasonable.
The last time I took a tube
head to the tech, he not only
wanted the amp but a Benjamin up front(bench fee) also.
This was almost a decade ago.
On the plus side, he did buy me
(and his family) dinner on that hundred.

 

[Interceptor]

I need to say this again.

As tech marches forward, replacing things out of desire for improved performance is interestingly well aligned with the reliability / parts upheaval in practice in the semiconductor manufacturing chain. Right about when something gets hard to fix, the new stuff eclipses it anyways.

 

[JGR]

What's really interesting is our government doesn't follow its own rules I know this for performing top secret things on top secret government items. Anything that is manufactured for our government for ***** purposes is above all of the environmental hoopla hoops they have us jumping through. Processes that everyone thought was totally outlawed and banished from existence is still being performed at record pace for the government, while government has put the squeeze on folks trying to make a living for their families.

In certain instances maybe, but not as a whole - that's a huge and inaccurate generalization. And if you really work top secret, you don't post about it on the Internet.

 

[Red Planet]

In certain instances maybe, but not as a whole - that's a huge and inaccurate generalization. And if you really work top secret, you don't post about it on the Internet.

So your saying im making that up? Im not.

 

[primusfan1989]

You probably should. A sample of 30 is statistically much more valid then a sample of 1.

Seeing that we're not even sure if we're talking about the same model of amplifier,

So, out of a sample quantity of one a single amp failed, you don't know why, it's fully covered under warranty so it's disposable? Your conclusion does not match my decades of QSC experience either.

I will also say with certainty that every class D bass amp that I have designed (for GB) is still fully supported and repairable. Not 25%, or 50% but 100% repairable AND I have been doing this for TB members for YEARS here on the forum. Both at the component level in most cases but sometimes it's less expensive to repair at the board level (on a case by case basis). For the most common products in the line, the labor charge is only $75 including all parts except tubes and power module, and in all of last year I only replaced 2 power modules. I don't see how this is uneconomical for a repair?

Your OPINION is that they are not repairable and thus disposable. My FACTS are that they are both repairable AND not disposable, backed up by actually doing this very thing. Let's not confuse opinion with fact.



Absolutely. There can be catastrophic failures with ANY product, and if the product has little value (or has an obsolete feature set) then it may not be worth repairing but most manufacturers will support products that have value. Now there are some companies that just don't care about ANY product out of warranty, or their cost of repair is inflated to where it doesn't make any sense to repair, but that is a specific business model that sacrifices low cost for low customer service and support. To that, I just say that it may be a better value to pick the companies you do business with a little more carefully... or don't bitch about products not being repairable.

I'm not bitching about anything, I offered my two cents on class d power sections, the subject of this thread. You obviously have taken my comments personally ... chill out. My experience in the subject is purely second hand based on experiences of people I know who've had bad experiences, enough experiences to make me go "I think I'm gonna wait another five years before looking into this technology, see if it gets better." I have friends who've had good experiences with class d stuff, one friend has one of the amps you apparently designed and has nothing but good things to say about it, apparently it's been very reliable. But the majority I've seen and heard have been negative experiences. I'm not trying to trash any particular manufacturer, my hang up is with class d in general, im not impessed and I don't put much faith in it. I'm glad they're working in movie theatres, I'm glad they work in your lab and testing facilities, my opinion is they're not working in the trenches of the working musician. Opinions are like a**h***s, everyone has one and most of them stink.

 

[JGR]

So your saying im making that up? Im not.

Nope, just saying that these days it's the exception rather than the rule, and that you shouldn't be talking about your association with classified work on a public forum.

 

[Passinwind]

Maybe it has changed, but up til recently, the only class-D amplifier in the QSC portfolio is/was the PL380. All others were class-A/B or class-H.

There are a few newer Class D lines besides the PowerLight series these days, but IME the vast majority of their standalone amps seen in MI and club level installations are indeed A/B or H.

 

[agedhorse]

I'm not talking about them working in the lab, class D amps I have designed have many thousands of successful hours in the touring world as well. Throwing unverifiable second hand experiences in with verified first hand experiences is like comparing dogs with pigs.

YOU might have had a bad experience, but that doesn't represent the market as a whole. In fact, you just might have been an unlucky guy that day.

From the experienced side of things, I can say (now that I can look back 10 years) that the reliability of my class D stuff is at least as good as the reliability of my class AB/G/H stuff and MORE reliable than my tube power amps. This is over a sample size of way greater than 10,000 amps.

 

[JGR]

Yup, last year ICE actually added a year on to their module warranty because their failure rates have been so low.

 

[Jim C]

Back to the environmental topic and spray painting.
I had read that the air leaving the Fender paint shop is cleaner than the air going in.
The big number for a spray booth will just be amortized based on the number of units painted, the planned number of years for this asset, and the price to the consumer.
This is the cost of doing business in a developed country.

Years ago she I was in manufacturing, we could get nearly any type of plating done in Alexandria VA for a great price including MIL spec hard chroming.
At this point, even clear zinc plating has gotten expensive and the EPA has forced of chrome plating through the roof.
This is actually a good thing due to the environmental impact of disposing of a very hazardous chemical by-product.
This is also why even little manufacturers chrome plate overseas as often times the spent chemicals are just thrown in the gravel parking lot to be absorbed by the land, creeks, and rivers.
Think about this the next time you use something like a ballpoint pen that just had to have a chrome part to look shiny.

 

[agedhorse]

I worked many, many years ago in the hard chrome plating industry, hard chrome is used an a lot of industrial machinery (things like injection molding extruder screws) to minimize wear, and while the regulations are complex and costly to maintain, it's still done here. It is a lot cheaper to do elsewhere though (for parts that can be shipped).

 

[Red Planet]

So many processes like salt bath nitride, the use of beryllium, and many many many others (would have to go look them up and no way I'm hopping in that system for this) are the every day norm for manufacturing for the government but are outlawed for private use. The government is exempt from its own rules despite what they tell you.

I would never disclose anything that would compromise anything and I sure dont need anyone implying that I would.

 

[dukeorock]

So many processes like salt bath nitride, the use of beryllium, and many many many others (would have to go look them up and no way I'm hopping in that system for this) are the every day norm for manufacturing for the government but are outlawed for private use. The government is exempt from its own rules despite what they tell you.

I would never disclose anything that would compromise anything and I sure dont need anyone implying that I would.

Then wouldn't the best course of action be to drop the subject and get back to the topic of this thread?

 

[Red Planet]

Then wouldn't the best course of action be to drop the subject and get back to the topic of this thread?

I'm game if you are?

 

[Red Planet]

So in keeping with thread and adding to the discussion materials. I'm fairly certain most of these new micros are compliant with RoHS2 and REACH compliant. I believe lead free solder as it ages has a tendency to grow whiskers. I don't think I have seen any research that has fully countered this anomaly though I wouldn't claim to be up on that sort of thing. Anyone care to chime in on this? I would think many other amps besides micros are using lead free solder these days as well. I purchased enough solder a while back to last me a lifetime in case it starts going away.

 

[agedhorse]

So in keeping with thread and adding to the discussion materials. I'm fairly certain most of these new micros are compliant with RoHS2 and REACH compliant. I believe lead free solder as it ages has a tendency to grow whiskers. I don't think I have seen any research that has fully countered this anomaly though I wouldn't claim to be up on that sort of thing. Anyone care to chime in on this? I would think many other amps besides micros are using lead free solder these days as well. I purchased enough solder a while back to last me a lifetime in case it starts going away.

Sure the industry has adopted lead free solders, I was designing products back in 2005 that were RoHS compliant (several years before required) and have had zero problems in those early products over all these years. Sure it requires a little more work, attention to detail, layout techniques, solder chemistry analysis, but done right there is absolutely no problems doing it JUST AS WELL as before. Whiskering is only a problem with very fine pitch layouts (WAY finer than we see in the amp industry), and when the processing is not clean with correct chemistry. Like everything else in this world, done right it's no problem, but done wrong can certainly be problematic. Choosing a supplier that does things right is really a no-brainer, and not all that difficult either. Kind of like... duh!

 

[JGR]

So many processes like salt bath nitride, the use of beryllium, and many many many others (would have to go look them up and no way I'm hopping in that system for this) are the every day norm for manufacturing for the government but are outlawed for private use. The government is exempt from its own rules despite what they tell you.

I would never disclose anything that would compromise anything and I sure dont need anyone implying that I would.

Nobody said that you would. The most basic premise of having a clearance is that you don't disclose it to people who don't have a need to know - you certainly don't post it in public forum for the sake of trying to sound impressive. The defense industry has been going to great lengths for some time to eliminate Beryllium from its products - it still exists in very specialized applications, but again you are painting a picture that is grossly inaccurate.

 

[Red Planet]

JGR if you cannot make your argument then by all means resort to name calling and stating my thoughts for me (which I'm fairly certain you've not a clue). Heck why don't you do my posting for me too.

 

[chiplexic]

What comes to mind while reading these posts is how NAFTA was sold on us by telling us...Oh don't worry about manufacturing job loses to overseas, we're going to become more of a service based industry here in U.S....I guess not so much.