FTC Amplifier Rule

[TLS Guy]

Consumer audio is a choice- we can life without it. The electronics industry classifies AV and other entertainment as 'lifestyle' but audio systems that need to continue operating during a fire, like a PA that announces where exits and safe places are during a storm, fire, attack, etc are called 'life safety'. In those systems, the specs call for the amplifiers to continue operating up to and including the point of destruction. Lifestyle vs life safety are real categories in the electronics industry- among others, alarm and video surveillance systems, medical monitors, various detectors and anything else that will keep people safe are in the latter group.

There is no requirement that an AV system operate at its maximum for a long time, other than maybe what a user demands. The FTC or any other government agency don't require it, but some manufacturers still use long term application in their specs because system designers want to know what to expect. Most people don't operate their system at maximum and anyone who does, needs to make sure the SPL isn't so high that it will damage their hearing if they want to hold a conversation in their later years. .

I see where you are coming from, however this gear is now a substantial hunk of change. The big issue as I see it, is this parameter more directly than you think speaks to reliability. If a unit is under stress, which with current specs, they will be. Then it points to short life. Too many receivers fail, and now with the increase in complexity costs have risen, but probably not as much as they should have. Reliability of receivers is not good enough, and few are happy with four ohm loads, which actually most loads are. So they are getting less and less fit for purpose. Failure of units north of 2K is a definite life style problem. This is also compounded by the fact that I understand you seldom get prompt, convenient and courteous service in the event of failure. Too often service is not even available under the excuse parts are not available, because the production run of critical ICs was not large enough.

This is another reason I'm so keen on active speakers, as the amps are driving one speaker frequency band, and there is none of this power sharing and sleight of hand. This is one of a number of reasons why failure in car audio systems is so rare, even though the operating environment is harsh. Car speaker systems I would point out, have been active for some time.

So I would encourage members to pony up the funds up front and go the pre/pro route, with external amps, and as time passes encourage more and more to purchase active speakers. Then you can build life time systems and save a lot of money in the long run. We have huge denial here on how bad a bargain a receiver actually is.

 

[Verdinut]

But why go for the pre/pro route when you can use a midline or flagship Denon receiver for instance. You will save a lot of money when you use it in its preamp mode with external amplication, and are able to obtain reliable performance. That is what I do with my AVR-X3700H.

 

[lovinthehd]

Why would amps in active speakers last so long particularly, tho? Lifetime seems a big assumption of quality. They'll go cheap there, too if not already. They're all of higher quality than current avrs? I've never had a car with an active speaker myself....but my newest vehicle is 2007.

 

[Verdinut]

Why would amps in active speakers last so long particularly, tho? Lifetime seems a big assumption of quality. They'll go cheap there, too if not already. They're all of higher quality than current avrs? I've never had a car with an active speaker myself....but my newest vehicle is 2007.

I think that TLS Guy uses the active speaker definition also for external amplification with passive speakers.

 

[lovinthehd]

I think that TLS Guy uses the active speaker definition also for external amplification with passive speakers.

Active speakers with external amps and active crossovers could well be a different reliability range...I do use a combo of head unit for front door speakers and separate amps for additional speakers and sub in my truck....but the speakers have passive crossovers....

 

[TLS Guy]

Why would amps in active speakers last so long particularly, tho? Lifetime seems a big assumption of quality. They'll go cheap there, too if not already. They're all of higher quality than current avrs? I've never had a car with an active speaker myself....but my newest vehicle is 2007.

For lots of reasons. The first is that the power amps can be sized precisely for their loads, bass, mid and HF. Their loads will be simpler, as they will not be fighting complex inductive and reactive loads. In addition, they will not have wasted power. I can't emphasize enough that at a minimum half your amp power is wasted in the passive crossover, and often more. As order and complexity of a crossover increase more amp power is wasted, and the load often gets more complex.
Ventilation is much easier, as there will only be two a three power amp modules in each speaker.

As you add power amps to a power supply the stresses and heat build up. That also applies to power amps as you increase the number of channels in one box.

There are now many highly reliable class D amp modules. If I was designing my system now, and not 2004/2005 I would design it totally active with amps and crossovers in the speakers. Now I have 18 amp channels from nine two channel amps in the power amp case in the chase, and an extractor fan venting outside the home. The speaker cabling is 650 feet, so that is not an ideal elegant solution. In a room as large as this, low impedance balanced cabling would be required from pre/pro speakers if the amps and crossovers were in the speakers. So a receiver would not fit the bill, even if you did not use the amps. Having unused amps, obstructing ventilation and running quiescent all the time is not an elegant option.

Already designs are in the works for active speakers to be connected to pre/pros with cat6 cabling, which is easy to run and cheap. It might be better in my view to use an optical system, which would eliminate ground loop possibilities. Things are going to change and they have to. Current practice is far from optimal and not at all elegant.

Your car may have an active speakers system and you don't know it. My wife's Merc 1998, was the first car of ours to have an active sound system that I know of. It was JBL.

My wife's 2009 Toyota Camry Hybrid has an active Pioneer system. That car was bought in 2008 and never any trouble with the sound system despite very harsh climatic condition in these parts.

My 2011 Chevy Equinox had a very good active system. That was the only part of that piece of excrement that never gave any trouble.

My current 2019 Toyota RAV 4 Hybrid has an active JBL system which is excellent. None of these systems have given any trouble whatsoever. They are far more reliable than the systems of old, which were not active. These car systems were pioneered by the Germans, especially Audi and VW who put enormous resources into in car entertainment. It is a truism that the best sound system most people own is in their cars!

Lastly, as this technology becomes the rule, then the Pre/Pro head units will become much cheaper, as there will be far less parts, smaller power supplies and digital outputs. They will also be quite small. We here members complain continually, that their wives don't like those big black boxes in their living spaces. In addition with class D technology speakers will be smaller and yet more powerful as those active crossovers and class D amps will able to provide the power for EQ. This revolution in practice will allow for an advancement in speaker technology as well, and that has already started.

As multi channel immersive systems proliferate, pre/pro "head units' and digital connection to active speakers is the only sensible, reliable and elegant way forward without more chaos and problems than we have now. We are now in the early phase of this revolution, but I expect it to pick up pace.

 

[lovinthehd]

For lots of reasons. The first is that the power amps can be sized precisely for their loads, bass, mid and HF. Their loads will be simpler, as they will not be fighting complex inductive and reactive loads. In addition, they will not have wasted power. I can't emphasize enough that at a minimum half your amp power is wasted in the passive crossover, and often more. As order and complexity of a crossover increase more amp power is wasted, and the load often gets more complex.
Ventilation is much easier, as there will only be two a three power amp modules in each speaker.

As you add power amps to a power supply the stresses and heat build up. That also applies to power amps as you increase the number of channels in one box.

There are now many highly reliable class D amp modules. If I was designing my system now, and not 2004/2005 I would design it totally active with amps and crossovers in the speakers. Now I have 18 amp channels from nine two channel amps in the power amp case in the chase, and an extractor fan venting outside the home. The speaker cabling is 650 feet, so that is not an ideal elegant solution. In a room as large as this, low impedance balanced cabling would be required from pre/pro speakers if the amps and crossovers were in the speakers. So a receiver would not fit the bill, even if you did not use the amps. Having unused amps, obstructing ventilation and running quiescent all the time is not an elegant option.

Already designs are in the works for active speakers to be connected to pre/pros with cat6 cabling, which is easy to run and cheap. It might be better in my view to use an optical system, which would eliminate ground loop possibilities. Things are going to change and they have to. Current practice is far from optimal and not at all elegant.

Your car may have an active speakers system and you don't know it. My wife's Merc 1998, was the first car of ours to have an active sound system that I know of. It was JBL.

My wife's 2009 Toyota Camry Hybrid has an active Pioneer system. That car was bought in 2008 and never any trouble with the sound system despite very harsh climatic condition in these parts.

My 2011 Chevy Equinox had a very good active system. That was the only part of that piece of excrement that never gave any trouble.

My current 2019 Toyota RAV 4 Hybrid has an active JBL system which is excellent. None of these systems have given any trouble whatsoever. They are far more reliable than the systems of old, which were not active. These car systems were pioneered by the Germans, especially Audi and VW who put enormous resources into in car entertainment. It is a truism that the best sound system most people own is in their cars!

Lastly, as this technology becomes the rule, then the Pre/Pro head units will become much cheaper, as there will be far less parts, smaller power supplies and digital outputs. They will also be quite small. We here members complain continually, that their wives don't like those big black boxes in their living spaces. In addition with class D technology speakers will be smaller and yet more powerful as those active crossovers and class D amps will able to provide the power for EQ. This revolution in practice will allow for an advancement in speaker technology as well, and that has already started.

As multi channel immersive systems proliferate, pre/pro "head units' and digital connection to active speakers is the only sensible, reliable and elegant way forward without more chaos and problems than we have now. We are now in the early phase of this revolution, but I expect it to pick up pace.

As far as vehicles, I had a 98 MB with Bose, it had a "sub" but do not believe it was particularly active beyond that but never dug into it. Think my '05 MB might be now that I think about it due tweeter placemet. Definitely not the truck, and the truck has the best system compared to the Bose stuff.

While I can appreciate that it can be done with quality onboard amps, I'm just not convinced the modules will be particularly long lived let alone serviceable/replaceable down the line at some point. Just the nature of consumer electronics. AVRs could be better, too, sure....

 

[TLS Guy]

As far as vehicles, I had a 98 MB with Bose, it had a "sub" but do not believe it was particularly active beyond that but never dug into it. Think my '05 MB might be now that I think about it due tweeter placemet. Definitely not the truck, and the truck has the best system compared to the Bose stuff.

While I can appreciate that it can be done with quality onboard amps, I'm just not convinced the modules will be particularly long lived let alone serviceable/replaceable down the line at some point. Just the nature of consumer electronics. AVRs could be better, too, sure....

We will see. There are already very reliable class D amp modules from Hypex and Purifi. It is true that making good ones is a design challenge, but those manufactures, especially Hypex solved these problems some time ago now. These amps, are highly efficient and make little heat. I would put my money and those amps installed on the back of speakers having a far, far longer life than a bunch of class A/B amps crammed into a receiver, blasting their heat all over delicate processing circuitry. People have been used to the receiver concept in one way or another since the seventies, but it was always a bad idea, and became a very bad idea as channels proliferated, and processing chips got put in the same box. It is a concept now beyond redemption.

The reliability of car audio systems shows that these small class D amps can be very reliable, even in very harsh environments. What we have in home audio now is just not acceptable with reliability far too low given the investment in the units.

 

[highfigh]

I see where you are coming from, however this gear is now a substantial hunk of change. The big issue as I see it, is this parameter more directly than you think speaks to reliability. If a unit is under stress, which with current specs, they will be. Then it points to short life. Too many receivers fail, and now with the increase in complexity costs have risen, but probably not as much as they should have. Reliability of receivers is not good enough, and few are happy with four ohm loads, which actually most loads are. So they are getting less and less fit for purpose. Failure of units north of 2K is a definite life style problem. This is also compounded by the fact that I understand you seldom get prompt, convenient and courteous service in the event of failure. Too often service is not even available under the excuse parts are not available, because the production run of critical ICs was not large enough.

This is another reason I'm so keen on active speakers, as the amps are driving one speaker frequency band, and there is none of this power sharing and sleight of hand. This is one of a number of reasons why failure in car audio systems is so rare, even though the operating environment is harsh. Car speaker systems I would point out, have been active for some time.

So I would encourage members to pony up the funds up front and go the pre/pro route, with external amps, and as time passes encourage more and more to purchase active speakers. Then you can build life time systems and save a lot of money in the long run. We have huge denial here on how bad a bargain a receiver actually is.

When I use 'lifestyle', it has nothing to do with the quality of life after making the choice to buy it- it's an actual category in the electronics industry, life safety is another and it has nothing to do with sound quality but the specs used for it are what a former AH member was harping about around ten years ago before he left- he had become very argumentative about what an amplifier needs to do, be and what it needs to survive. I think his first name was Frank.

As I have posted, I think more equipment needs to be modular, but that makes manufacturers sad because they wouldn't push as many boxes out the door or, the majority of the boxes would be much smaller and that equals 'less money'.

I have written that I want amplifiers to develop the power they state with ALL channels driven, which basically means "must have a very robust power supply" and really, not much more. That's where most amplifiers fail to perform- the power supply can't keep up with the demand. I have seen amplifiers that failed and it's not pretty. Well, I guess it is if someone likes literal fireworks, but inside a cabinet, that's not a good thing.

I have thought that active crossovers should have been used more for a long time but it's foreign territory for so many people that the manufacturers would have had a hard time selling it and since sales reps are usually clueless about the technology in the equipment they push, those of us in the industry are left to use pro equipment in many cases or, if possible and practical, experiment with new things as they come along.

If more manufacturers and consumer audio consumers had the chance to hear some of the speakers with internal DSP and amplification, I think they would change their minds but most don't have access or don't know where to go in order to see/hear them.

 

[highfigh]

We will see. There are already very reliable class D amp modules from Hypex and Purifi. It is true that making good ones is a design challenge, but those manufactures, especially Hypex solved these problems some time ago now. These amps, are highly efficient and make little heat. I would put my money and those amps installed on the back of speakers having a far, far longer life than a bunch of class A/B amps crammed into a receiver, blasting their heat all over delicate processing circuitry. People have been used to the receiver concept in one way or another since the seventies, but it was always a bad idea, and became a very bad idea as channels proliferated, and processing chips got put in the same box. It is a concept now beyond redemption.

The reliability of car audio systems shows that these small class D amps can be very reliable, even in very harsh environments. What we have in home audio now is just not acceptable with reliability far too low given the investment in the units.

The consumer audio failure rate for equipment when I started selling audio was about 1%- if they hit that number now, I would be surprised. I recently sold an integrated amp that was made in 1989 and it still sounds great- your amplifiers are much older and because they were built with durability and reliability as main criteria, you're still using them. If they have a problem, they're serviceable and that's where I have a huge problem with most of the stuff that's troweled out by the various companies that say they make great stuff- try to buy replacement parts in ten years and for that matter, try to find someone to service it, since the manufacturers stopped training service techs long ago. The rest have retired, died, lost interest and/or moved on to work somewhere else. You can make repairs, some others here and elsewhere can do this but the vast majority of consumers don't know which end of a screwdriver to pound on- ask them to look into an electronic problem? Not a chance.

They need to separate the controls from the power amp. Should have done that decades ago.

But, COVID and the shortage of electronic components notwithstanding, it's easy to go to a store and walk out with a new AVR, so that's great. Just great. Then, they can do the same in a few years when the previous one pukes.

 

[highfigh]

Active speakers with external amps and active crossovers could well be a different reliability range...I do use a combo of head unit for front door speakers and separate amps for additional speakers and sub in my truck....but the speakers have passive crossovers....

Active crossovers in head units was used in the late-'70s, by Sanyo. They had a few bi-amped head units that crossed over at 2KHz and we used to separate the tweeter or mid/tweeter in coax/triaxial speakers frequently. The problem- many people didn't understand how to use the controls, even though we spent a good amount of time showing and explaining it to them. Also, they didn't sound great.

Now, many car/marine audio manufacturers are putting a DSP in the amp, rather than just a group of switches/pots for the crossovers and levels with some offering an external DSP. This makes life for those who are setting up the system much easier, as long as they understand it- using the Audio Control 3050 or 3050a RTA was a challenge because each band had a stack of round, red LEDS and it was anything but truly 'graphic'. It worked, though. Now, Audio Control has things like this-

JL has this-

 

[lovinthehd]

We will see. There are already very reliable class D amp modules from Hypex and Purifi. It is true that making good ones is a design challenge, but those manufactures, especially Hypex solved these problems some time ago now. These amps, are highly efficient and make little heat. I would put my money and those amps installed on the back of speakers having a far, far longer life than a bunch of class A/B amps crammed into a receiver, blasting their heat all over delicate processing circuitry. People have been used to the receiver concept in one way or another since the seventies, but it was always a bad idea, and became a very bad idea as channels proliferated, and processing chips got put in the same box. It is a concept now beyond redemption.

The reliability of car audio systems shows that these small class D amps can be very reliable, even in very harsh environments. What we have in home audio now is just not acceptable with reliability far too low given the investment in the units.

I don't doubt Hypex and Purifi can do well enough, but will everyone use such quality amps? Do they make versions suited to automobile environments?

 

[Replicant 7]

Any updated news on rule's yet? FTC lately. Now that would be News!! Fines cease and desist don't see that happening anytime soon.

 

[highfigh]

I don't doubt Hypex and Purifi can do well enough, but will everyone use such quality amps? Do they make versions suited to automobile environments?

I think they'll need to be high quality if the manufacturers want to develop a following and someone will need to step up and be the first to do it at a price consumers don't see as 'excessive'. Amplified monitors have been used in studios for a long time and it definitely is time for them to come home.

Class D car amplifiers have been around since the '90s, although the ones I saw depended on stable impedance in order to perform properly. The one from Sony or Alpine (don't remember which), specifically, needed the impedance to remain as close to 4 Ohms as possible because the low frequency response would be badly affected. I may have some technical sheets from that time and if I find what I'll be looking for, I'll post them.

 

[highfigh]

If the FTC were to start using the Power Cube testing method, we would see some very robust amplifiers- I remember the Power Cube tests being used by some manufacturers in the '90s to show the capabilities of their products, but not by others because theirs performed badly. When they couldn't handle the reactive loads, they really had a hard time producing rated power. The link shows a couple of graphs and the second shows an amp that limits current when it runs into trouble, but some would also have problems with capacitive loads or inductive loads, or both- only at 0° Current phase shift.

I don't expect this to happen.

ap.com/technical-library/measuring-power-amplifiers-with-reactive-loads/

 

[PENG]

I don't expect this to happen.

ap.com/technical-library/measuring-power-amplifiers-with-reactive-loads/

I think you are right about this. It won't happen and there is no reason for FTC to do it, because aside from not being a significant enough safety concern, they most likely know that most consumers won't benefit from it. People like you, if you want a robust amp you know what to get already.

For most home HT people, they usually can get by with a 15-20 lbs soaked and wet Sony AVR (my brother has a 2 channel light weight Sony for years, still kicking as far as I know) and won't know even if the poor thing is clipping 90% of the time when watching action/horror movies. Reactive load with 45 to 60 degrees current lagging or leading should only present a challenge to such amps if the frequencies for those occurrence coincides with impedance dips below 4 or even 6 ohms and frequent enough, otherwise it won't be a big deal.

Regardless, many such AVRs and amps will not do well in those power cube tests mainly due to their lack of adequate heat sinks. It is more of a thermal issue so its the test duration that matters most. If the cube tests were performed for a short duration such as 10 seconds, may be even 30 seconds then I expect a lot more will past the test. Stability could be an issue too especially when current leads voltage (negative phase angles) but for modern amps with proper negative feedback it won't likely be an issue either.

Thanks for the link by the way, I may forward it to Amir over at ASR and try to convince him to do that test in his next opportunity. I doubt he would do it for every amp, but I would like to see him do it on an AVR lol..

 

[highfigh]

I think you are right about this. It won't happen and there is no reason for FTC to do it, because aside from not being a significant enough safety concern, they most likely know that most consumers won't benefit from it. People like you, if you want a robust amp you know what to get already.

For most home HT people, they usually can get by with a 15-20 lbs soaked and wet Sony AVR (my brother has a 2 channel light weight Sony for years, still kicking as far as I know) and won't know even if the poor thing is clipping 90% of the time when watching action/horror movies. Reactive load with 45 to 60 degrees current lagging or leading should only present a challenge to such amps if the frequencies for those occurrence coincides with impedance dips below 4 or even 6 ohms and frequent enough, otherwise it won't be a big deal.

Regardless, many such AVRs and amps will not do well in those power cube tests mainly due to their lack of adequate heat sinks. It is more of a thermal issue so its the test duration that matters most. If the cube tests were performed for a short duration such as 10 seconds, may be even 30 seconds then I expect a lot more will past the test. Stability could be an issue too especially when current leads voltage (negative phase angles) but for modern amps with proper negative feedback it won't likely be an issue either.

Thanks for the link by the way, I may forward it to Amir over at ASR and try to convince him to do that test in his next opportunity. I doubt he would do it for every amp, but I would like to see him do it on an AVR lol..

The FTC has a responsibility to make sure products and services are as advertised and industry standards are a good start, but the manufacturers need to adhere to them in order for them to do any good. They don't seem to be doing much, but hey- it's the government, right?

WRT phase angle, we see the problems this causes in speaker analysis constantly- why is it not a big deal? Anything that reproduces bass would be affected, not just subwoofer amplifiers.

Not just heat sinks, it's also in the power supply design and components chosen for the design. Without these two considerations, an amp has no chance of surviving, let alone performing well.

Rockford Fosgate provided Power Cube data to us when we were at their car audio training- I'll post some of the comparisons after I retrieve them.

FWIW, at one point, Sony car audio power ratings were called 'Sony Watts', '100W JBF' and sometimes, 100W WLS'- JBF stood for 'Just Before Fire' and WLS stood for 'When Lightning Strikes'.

OTOH, I have owned several Sony amplifiers and still have a stereo receiver, all from about 1974-1978 and all exceeded the power ratings in magazine testing and at the stereo store where I worked. We had a BPi distortion analyzer and techs who knew how to perform these measurements. They outperformed the spec sheets by a wide margin in wide bandwidth testing, too- now, they're tested at 1KHz. Great.......

 

[PENG]

WRT phase angle, we see the problems this causes in speaker analysis constantly- why is it not a big deal? Anything that reproduces bass would be affected, not just subwoofer amplifiers.

You might have missed my point, as I did qualify my statement, I said "Reactive load with 45 to 60 degrees current lagging or leading should only present a challenge to such amps if the frequencies for those occurrence coincides with impedance dips below 4 or even 6 ohms and frequent enough, otherwise it won't be a big deal. " I never said it isn't a big deal because in some cases it could be a big deal, especially if it has large leading phase angles that may cause stability issue.

 

[CreoleDC]

Some of you guy's just soon apply for a job with the FTC. Seem like a whole bunch of you fellows know lots about audio.
Could help speed up thing with them FTC guy's been dragging their feet for how long now months years decades.