So What Are Them WATTS These Days????

[RayCJ]

Originally Posted by SpruceTop

Maybe the electrical engineers will chime in on this tongue-in-cheek scenario? I'm assuming with the right design, engineering and high-capacity capacitors, amps capable of super-high, peak-wattage ratings are possible. If so, how long will it be before amp companies start upping the ante in the watt wars for our dollars by offering audio amps advertised with 5,000- or 10,000-watt ratings aimed at giggers? Is it possible to do this while keeping the weight and cost reasonable for amps with these high peak-wattage ratings? I'm thinking amps of this power would likely trip a breaker in a typical 120-volt, 15- to 20-amp line if driven even moderately, wouldn't they? Although impractical and unnecessary for most of us, amps with these high wattage ratings could be used as a marketing tool to lure buyers to a company's products; if one company comes up with a product with these ratings, others will follow! Any thoughts on the possibility of something like this happening?

From my post above which I think were posted within moments of each-other:

" Those peak Watt ratings are for very brief periods of time. You can put your finger on frying pan for a split second without getting a blister... -Just don't hold it there for more than a split second. At really, really high power ratings... think about if you have a glowing red hot piece of metal. If you put your fingertip on it for a split second, you will instantly regret it (i.e. blown speaker). "


Anyhow, 10,000 Watt systems already exist. They're used in shopping malls etc... I think Crown and McIntosh make stuff along those lines.


Ray

[SpruceTop]

Originally Posted by RayCJ

From my post above which I think were posted within moments of each-other:

" Those peak Watt ratings are for very brief periods of time. You can put your finger on frying pan for a split second without getting a blister... -Just don't hold it there for more than a split second. At really, really high power ratings... think about if you have a glowing red hot piece of metal. If you put your fingertip on it for a split second, you will instantly regret it (i.e. blown speaker). "


Anyhow, 10,000 Watt systems already exist. They're used in shopping malls etc... I think Crown and McIntosh make stuff along those lines.


Ray

Thanks Ray,

I understand but could these high-powered amps be adapted and marketed to avid consumers like us, many of whom would be sucked into the wattage ratings and plunk their money down? The wattage war already is being fought in the 800- to 2000-watt range (peak or burst watts), so I'm wondering if it could ever escalate to higher ratings?

[SpruceTop]

Speaking of high-wattage, overkill amps, does anyone remember the Bose amp in the road case that was rated at 250-watts RMS per channel into 8-ohms at .5% THD distortion? Back in 1978, I bought one of these from Whirlwind Audio, here in Rochester. I used it as the amp for my first high-end component PA system. Needless to say, I didn't use it for long because its weight was 65 lbs! I returned it for a Crown DC-300A, which was another great amp of the era, rated at 155-watts RMS per channel into 8-ohms. It's funny how the amps in those days were rated in RMS, which, I believe, was a more realistic measure of their long-term power rating. Likely, a 250-watt RMS per channel power amp back then could be rated using today's peak-wattage ratings at maybe 1000-watts per channel. Any thoughts on this? Can the power of today's Class D amps be compared directly to the older and heavier power amps of 35-40 years ago or does yesterday's amp design preclude a direct comparison of any measure of wattage, be it RMS, Continuous, or Peak?

[RayCJ]

Originally Posted by SpruceTop

Thanks Ray,

I understand but could these high-powered amps be adapted and marketed to avid consumers like us, many of whom would be sucked into the wattage ratings and plunk their money down? The wattage war already is being fought in the 800- to 2000-watt range (peak or burst watts), so I'm wondering if it could ever escalate to higher ratings?

I don't have an answer for you there... I spent plenty of time working with marketing and sales teams but, not related to consumer stuff like this.

Other than typical product safety standards, I don't think any government agency regulates the specifications of consumer amplifier/audio equipment. I could be wrong and if any gov agency is involved, it would be the FCC -but I doubt they care about this. Anyhow, if my assumption about a lack of binding regulation is correct, sure, they can make-up any bogus nonsense they want. -Just guessing...


Ray

[SpruceTop]

Originally Posted by RayCJ

I don't have an answer for you there... I spent plenty of time working with marketing and sales teams but, not related to consumer stuff like this.

Other than typical product safety standards, I don't think any government agency regulates the specifications of consumer amplifier/audio equipment. I could be wrong and if any gov agency is involved, it would be the FCC -but I doubt they care about this. Anyhow, if my assumption about a lack of binding regulation is correct, sure, they can make-up any bogus nonsense they want. -Just guessing...


Ray

The ratings wouldn't really be bogus or false advertising if the amps could deliver the wattage claimed even if it were peak or burst wattage if it were stated as so. As referenced in my post up the board a bit, it seemed to me back in the 1970s and 1980s that pro-audio power amps advertised their wattage-ratings in RMS watts into a specified ohm-load, at a certain level of distortion, with both channels driven, and maybe this also included over the range of 20 Hz - 20,000 Hz. Of course, owing to all the iron and other components in them, these amps were heavy compared to today's Class D amps. I'm wondering if weight wasn't a factor of consideration, would an older amp design, like the venerable Crown DC-300A, be more preferable over a wide-range of conditions compared to a newer Class D design amp?

[SpruceTop]

Does anyone know why, since the advent of Class D amps, active PA speakers that contain them have been advertised with high wattage-ratings? Is there something in the Class D design that warrants or compels the listing of high-wattage ratings?

[RayCJ]

Originally Posted by SpruceTop

Speaking of high-wattage, overkill amps, does anyone remember the Bose amp in the road case that was rated at 250-watts RMS per channel into 8-ohms at .5% THD distortion? Back in 1978, I bought one of these from Whirlwind Audio, here in Rochester. I used it as the amp for my first high-end component PA system. Needless to say, I didn't use it for long because its weight was 65 lbs! I returned it for a Crown DC-300A, which was another great amp of the era, rated at 155-watts RMS per channel into 8-ohms. It's funny how the amps in those days were rated in RMS, which, I believe, was a more realistic measure of their long-term power rating. Likely, a 250-watt RMS per channel power amp back then could be rated using today's peak-wattage ratings at maybe 1000-watts per channel. Any thoughts on this? Can the power of today's Class D amps be compared directly to the older and heavier power amps of 35-40 years ago or does yesterday's amp design preclude a direct comparison of any measure of wattage, be it RMS, Continuous, or Peak?

It's been a little while since I last did any serious work in this area but....

RMS (Root Mean Squared) is a good way of looking at things but only if the input signal is constrained to be symmetric and periodic. Vocal or musical audio is anything but symmetric and periodic so, you can't effectively do RMS calculations.

In my opinion, yes, those older days when power was defined with a limit of THD at a particular effective impendance, were superior methods of truly defining the capabilities of an amp. Even at that, those numbers could not tell you if the system sounded good or bad. It could however tell you if the equipment was suitable for your bedroom or a wedding hall.

Is there any way to convert the old rating methods to the new ones? Hmmmm... My guess is that the BS-factor is about 5:1 so, a modern 250W amp is actually 50 Old Watts. Seriously though... I don't know how they're calculating the number these days so, I can't answer that...


Ray

[RayCJ]

Originally Posted by SpruceTop

I'm wondering if weight wasn't a factor of consideration, would an older amp design, like the venerable Crown DC-300A, be more preferable over a wide-range of conditions compared to a newer Class D design amp?

Back in the day, weight was an indication of how big the power transformer was. A big transformer was bridge rectified and the resulting DC would feed a couple really big capacitors. Those capacitors drove the output side of the transistors (or vacuum tubes). Big, heavy transformer meant you could convert a lot of power to drive a big load. Now, the power transformers are solid state switching type. Just a few ounces instead of many, many pounds.

Class D vs the old stuff... Beats me which is better. Beyond a certain level, my ears can't tell any difference. Newer equipment is laden with Digital Signal Processing with very advanced filtering. If you're a computer techie, you'll like that better. If you like to rub your hands over the warmth of a McIntosh tube amp, you'll like that better. I doubt though if your ears will hear any difference ...


Ray

[myersbw]

Originally Posted by RayCJ

Those peak Watt ratings are for very brief periods of time. You can put your finger on frying pan for a split second without getting a blister... -Just don't hold it there for more than a split second. (i.e. blown speaker).

Ray

Ray actually hit upon a valid scenario and shame on you engineers for not picking up on it. LOL! TIME... something the energy companies have been doing for some time now.

Instead of measuring and giving us the elusive definition of "watts" now, we would get a more fair comparison of consumption (and output) if we went to watt-hours like the power companies use to assess and charge us.

The time factor is extremely important. I liked the old moniker of "continuous watts". That, by definition, gave you what you could expect for an indefinite period of time...not for just 1 millisecond or 2.

Going to a watt-hour rating would level the playing field for a more valid comparison (except for the SPL and efficiency comparisons).

Now, with respect to "output watts" changing if you add an external speaker...absolutely! You're changing the impedance that a given output transformer (or specific circuit design) sees. There's an ideal match for 'maximum power transfer' vary that on either side and you are "less efficient" and the max power won't be available at the output. If you want it in more consumer or laymen terms....go peak at PA amp power output ratings at different impedances or loads. The transferred power will vary.

We dealt with variation when Class A met up with Class B & C and A/B...etc. Now, we have D and T, etc. , to thoroughly confuse the consumers. Can you get that momentary burst? Why sure! But, don't expect to run the Class T alongside the Class A/B with the same "watt rating" and hear the same result.

Maybe we should lobby amp-makers to adopt the watt-hour ratings...? :P

Cheers!
Brad

[Mandobart]

Shame on us Engineers for what? You want to try and rate amps on energy vs power? Things aren't confusing enough for you already? The reason is the energy is the integral of the power and it is a non-linear function. In fact there are infinite possibilities for any amplifier. A given amp or speaker could maybe handle 2000 W for a millisecond. That does not mean it can handle 1000 W for 2 millisec, or 500 W for 4 millisec. The actually energy is the same in each case (2 joules) but that tells you nothing about real performance. It can probably handle 1 watt for much longer than 2 sec (still 2 joules). So an energy vs power rating could be spec'ed in an infinite number of ways.

Add to that the stress of cyclic loading (the amp/speaker can possibly handle 2000 W for 1 msec - can you safely do that for 1 msec out of every second? Can it be repeatedly loaded like that for a year without failing?) and you have complete confusion on what your gear can do and still have a reasonable service life. All ratings based on energy would be useless. To use a mechanical analogy, pushing a car or motorcycle past the engine's red line isn't going to immediately blow the motor. How long/far can you go at red line? How long will the engine last if continuously run just under red line? Should we insist motor vehicle mfrs specify that? Would they even be able to?

As flawed as it is, the current method of specifying power (VA, continuous watts RMS, program power, etc.) gives us a good estimate of what an amp can do continuously, not in some arbitrary transient.

[jonfields45]

I started this thread as part joke and part wake up call.

I tried various battery powered amps over the years and ended up buying a AGM battery and a cheap pseudo sine inverter to use my regular PA. None of the battery amps came close to sounding like what their power ratings meant to me (I'm 58 and played mostly through Fender combo amps gigging with a rock band in the 70s).

Power ratings on most PA speakers are ludicrous (at least for the models starting around $400 MAP) and I would never choose one over the other for power.

Small acoustic combos that you might want to stretch to play a small bar or noisy restaurant gig are where you might think these numbers are useful, but it is definitely Caveat Emptor!

I was originally inspired by a thread looking for feedback on the Giulia vs AG200. I'm certain there is enough headroom in the Carvin power rating to handle that noisy restaurant or bar regardless of how they cooked up the power rating. The Guilia, with only 35 watts of woofer biamp power and a relatively small 5" speaker, it would be impossible to know what it can do without trying it out. Where as I gigged for years with a 35 watt Fender Vibrolux Reverb playing un-miced in high school gyms at volumes no acoustic artist would entertain.

[MikeB1]

Thanks so much everyone, this has been a fascinating discussion.

Thanks Jon for coming back to my question. I think your advice is prudent. When all is said and done, it seems like you just have to try these things and get some experience with them. I will probably follow up and give Django Books a call. Thanks for the tip.

Ray's advice pertaining to covering the basics resonated with me also, especially just getting something you can carry around.

Given the weight difference and my bad back, I am leaning towards the Schertler Guilia Y over the Carvin. It seems logical to start with the lighter amp and see if that has what I am looking for.

[myersbw]

I get the joke for sure! Sorry, didn't mean to strike some hidden nerve, Mando...didn't mean to offend (maybe a chill pill is needed?)

But, I can see a somewhat better standard for performance expectations. For example, we sure aren't going to run an amp for 1 mS, but there can be a reference just like we have for some "dB" ratings. (lol, I won't go there either!)

So, given the current state of manufacturing, I suppose we can all invest in watt-meters and expected speaker loads and head for the local GC!

Cheers!