Home Audio Specs

[jwax]

Mr Al has mentioned this in speaker specs, but how does the home audio market get away with absurd specifications?
I just bought a Samsung Home Theater Sound System. 650 total watts out of 5 speaker modules. Loud?
Nope. You'd think 650 watts would irritate the neighbors down the road!
6 feet from the speakers and no ear protection required!
Not complaining as much as wonderment as to what specs mean anymore.
Besides, it came with speaker wire! 24 AWG. Scheesh.

[Robert Reed]

John
Its like anything else for sale:
Marketing bullsh*t and a very ignorant and apathetic generation of consumers.
A winning combination for sellers, but unfortunately not for our generation!!

Example - Is it quality? Who cares!
Is it cool? Yea, lets buy it!

[Externet]

< applause >
Well said.
Same goes for the crap sound on digital telephones. Intelligibility does not matter, but ringtones and flashy lights and color screen and able to play solitaire on your phone is what counts.

[jimmy101]

"650 total watts out of 5 speaker modules"
How was the power actually spec'd? It should be quoted as either RMS (reasonably accurate measure of output) and not "peak" or IHF (both are basically meaningless). And, it should spec that all channels are driven simultaneously and quote a THD (total harmonic distortion).

Decades ago amp manufacturers were doing similar things with their specs. Crappy little amps were being spec'd at 100's of watts. The feds cracked down and required that the details of how the spec's were measured had to be included. I believe those requirements were dropped ten years or so ago because of complaints of "nanny state". "The gov't has no right to tell manufacturers how they claim their specs ... the market can take care of itself ..." and similar BS.

[jwax]

The system is spec'd at 650 total, 150 watts of that is the subwoofer. 500 watts for the other 5 modules:

100 watts x 5 into 4 ohms (20-20,000 Hz) at 0.9% THD

In other words, those "watts" could be anything the manufacturer wants it to be.

[Externet]

John : Peek at the power consumption sticker in the back; about 70% of that is the true maximum output power.

Miguel

[MrAl]

Hi,


I second the applause out to Robert Reed for stating the truth about manufacturers !!!

That rot is spreading throughout all industries now, so one day people will be afraid to
buy anything without a complete demo. Note some stores wont allow an in store demo
anymore because they know already that the stuff isnt up to par, but they are betting
that if you take it home to try it out instead of in store that you wont feel like driving
back to return it.

A good way to compare amps is to find an old one made a long time ago and compare it's
loudness to that of a new one. You do have to make sure you have the correct speaker
impedance of course or that would screw up the comparison.

[MicroRem]

My office is located in a business park with a shop that specializes in car audio. I was talking to the manager who is very knowlegable and very honest with is customers. He introduced me to a new term about these power output ratings when he said many systems are rated "1200 Watts WLS" I asked him what WLS is.... he replied...When Lightning Strikes.

best to all

Tom

[jwax]

I asked him what WLS is.... he replied...When Lightning Strikes.

hehe
I was thinking perhaps the audio industry has secretly created a little-known parameter called the "dogwatt"-
7 "dogwatts" = one peak-to-peak watt.

[Dean Huster]

Was it "peak music power" or something like that they called it in 1965 to make a modest 35 watts rms balloon into hundreds of watts until the FTC got hold of them forcing the rms, THD and number of channels issues? Maybe the FTC rules are like copyright and have expiration dates. Either that, or these Class D home theater amps are super-duper efficient.

[Bob Scott]

Was it "peak music power" or something like that they called it in 1965 to make a modest 35 watts rms balloon into hundreds of watts until the FTC got hold of them forcing the rms, THD and number of channels issues?

I remember Watts IHF, Watts EIA, Peak Watts, Watts PP.
Here is a 1966 document from the Institute of High Fidelity (IHF) and printed in HIFI Stereo Review:

http://www.bassboy.com.au/getreel/class ... rticle.htm

In 1967, with money I earned over the summer, I bought a stereo amp by mail-order from Lafayette (LRE. Those catalogs with exclamation marks after every sentence!). The model LA-85T was advertised as 85 Watts IHF total power. Years after it blew for the last time and scrapped, a survivor crossed my bench around 1979. I decided to find the real power figure for it. I measured 18 Watts RMS/channel before clipping, one channel driven at a time. That is about the same power as a modern car radio with bridged outputs.

The new power ratings for automotive audio power in particular make those rediculous '60s power ratings look conservative in comparison.

[MrAl]

Hi again,


The newer ratings are sometimes called "dW" or "Plus100". That's either power output referenced to 100 watts or they take the actual rating and add 100 watts to it
Thus, a 10 watt true rated amp comes out to 110 watts

[Robert Reed]

The amplifier power ratings are a perfect match for the speaker ratings nowadays. Heres an example: An amp rated at 200 watts (the new BS rating) is coupled to a tweeter rated at 200 watts (again the new BS rating). They are in perfect harmony and work well together.
Now the reality: The tweeter would blow itself up with even 30 watts applied to it.The amp in reality only puts out 15 watts. Now the 200 watt speaker can easily handle the 200 watt amp at full bore- a perfect match.
Bottom line: The owner has bragging rights about his 200 watt system. The grossly overrated equipment works without blowing up!
Is this a case of two wrongs make a right?

[jwax]

Robert- That explains it perfectly! And if the trend continues, someday we'll all have gigawatt sound systems, and without hearing loss!

[gerty]

My students brag "I have a 1,000 watt amp" and the next one says " Oh yeah , well mine's 1,200 watts" When I tell them to apply Ohms Law and do the math, jaws drop. They then ask how can they be advertised with such high ratings, I like the WLS answer.
For most of them it's all about bragging rights.