[chlorofille]

Hi all,

Interesting numbers so far. Power ranging from 3 to 18,000 watts 
Maybe we can include ---> "how many watts is actually used for the average listening session".

[Wind Chaser]

Overall, high wattage doesn't guarantee sonic bliss.

Yes, but it also depends on the speaker.  Clean power is clean power, but some speakers cannot be driven with a flea amp.

[Wind Chaser]

"how many watts is actually used for the average listening session".

That's a more interesting question, which largely depends on the speakers and the preferred SPL.  I bet most people are not in the habit of listening in excess 90 db on a frequent basis.  Even 90 db is quite loud.  I listen somewhere between 72 - 80 db on average.  So in theory, a lot of people could get by with 10 watts - or less.

[joeling39]

I alternately between an 80W OTL & a 1KW digital amp (ICE). The OTL sounds so sweet & full of air & bloom. The digital sounds accurate & authoritative (bass is nice). I like to change the flavour once in a while. The truth is that my speakers probably only need 10W or less. Well, they (Mitsubishi Diatone full rangers) will blow up if fed more than 14W (stated in a more polite manner on the drivers).

I feel that it's the type of amplification device rather the wattage that makes a bigger difference.

Regards,
Joe Ling

[denjo]

50 watts into 8 ohms gives me more than enough SPL! It is not the quantity alone but the quality of the watts.

[Niteshade]

I agree- it's always quality before quantity. For the sake of discussion, I am assuming the amps being brought up all produce quality wattage.

How many watts is actually used in a typical listening session: I have measured this a few times. With 92db speakers, around 2-5 watts RMS. My VSA VR2's @ around 85db efficiency require 5-10 watts. Both rooms are about the same size. If music is played down low, it's no more than 1-2 watts for either speaker.

I have a receiver (JVC RX-999VBK) that has a very good watt meter installed. What caught my eye was the peak power produced during 5-10 watt listening sessions. It ramped up to nearly 30 watts at times! Peaks last a very short time- milliseconds. Listening at 10-20 watts would bring on peaks in the 80 watt range. The receiver is rated for 110 watts RMS per channel and has upgraded output transistors.

===============================

From Wikipedia:
"The term "Music Power" has been used in relation to both amplifiers and loudspeakers with some validity. When live music is recorded without amplitude compression or limiting, the resulting signal contains brief peaks of very much higher amplitude (20 dB or more) than the mean, and since power is proportional to the square of signal voltage their reproduction would require an amplifier capable of providing brief peaks of power around a hundred times greater than the average level. Thus the ideal 100-watt audio system would need to be capable of handling brief peaks of 10,000 watts in order to avoid clipping (see Programme levels). Most loudspeakers are in fact capable of withstanding peaks of several times their continuous rating (though not a hundred times), since thermal inertia prevents the voice coils from burning out on short bursts. It is therefore acceptable, and desirable, to drive a loudspeaker from a power amplifier with a higher continuous rating several times the steady power that the speaker can withstand, but only if care is taken not to overheat it; this is difficult, especially on modern recordings which tend to be heavily compressed and so can be played at high levels without the obvious distortion that would result from an uncompressed recording when the amplifier started clipping.

An amplifier can be designed with an audio output circuitry capable of generating a certain power level, but with a power supply unable to supply sufficient power for more than a very short time, and with heat sinking that will overheat dangerously if full output power is maintained for long. This makes good technical and commercial sense, as the amplifier can handle music with a relatively low mean power, but with brief peaks; a high 'music power' output can be advertised (and delivered), and money saved on the power supply and heat sink. Program sources that are significantly compressed are more likely to cause trouble, as the mean power can be much higher for the same peak power. Circuitry which protects the amplifier and power supply can prevent equipment damage in the case of sustained high power operation.

More sophisticated equipment usually used in a professional context has advanced circuitry which can handle high peak power levels without delivering more average power to the speakers than they and the amplifier can handle safely."

Entire article: http://en.wikipedia.org/wiki/Audio_power

[BobRex]

I agree- it's always quality before quantity. For the sake of discussion, I am assuming the amps being brought up all produce quality wattage.

How many watts is actually used in a typical listening session: I have measured this a few times. With 92db speakers, around 2-5 watts RMS. My VSA VR2's @ around 85db efficiency require 5-10 watts. Both rooms are about the same size. If music is played down low, it's no more than 1-2 watts for either speaker.

I have a receiver (JVC RX-999VBK) that has a very good watt meter installed. What caught my eye was the peak power produced during 5-10 watt listening sessions. It ramped up to nearly 30 watts at times! Peaks last a very short time- milliseconds. Listening at 10-20 watts would bring on peaks in the 80 watt range. The receiver is rated for 110 watts RMS per channel and has upgraded output transistors.

===============================

From Wikipedia:
"The term "Music Power" has been used in relation to both amplifiers and loudspeakers with some validity. When live music is recorded without amplitude compression or limiting, the resulting signal contains brief peaks of very much higher amplitude (20 dB or more) than the mean, and since power is proportional to the square of signal voltage their reproduction would require an amplifier capable of providing brief peaks of power around a hundred times greater than the average level. Thus the ideal 100-watt audio system would need to be capable of handling brief peaks of 10,000 watts in order to avoid clipping (see Programme levels).
Entire article: http://en.wikipedia.org/wiki/Audio_power

Leave it to Wikpedia and its contributors to create a truly terrible example.  Given a speaker with a sensitivity of 90dB, an "ideal 100-watt audio system" (whatever the hell that means) would produce a steady 110 dB at one meter per channel.  To assume that to be the mean level and add 20dB of signal above that is insane and dangerous to one's hearing.  (yeah, I know it's just an example and the math is easy, but c'mon!)

A more rational statement would be that given a speaker sensitivity of 90dB and an average listening level of 90dB (which is very loud), a 100 watt amplifier can easily generate the 20dB necessary to cover any peaks in the program material.

BTW - 10,000 watts (sheesh) would require 282.84 volts into an 8 ohm load.  Try that with a 110v service!

[Niteshade]

They were trying to demonstrate peak power demands via mathematics. They are talking about an amplifier with ideal transient response capabilities. Most any output device can handle several times its power rating for very short periods of time. Naturally, power supply limitations inhibit transient response power.

The difference between average and transient response power output can be enormous.

This brings us up to recording with compression to make playback compatible on a wider range of audio systems.

[Thebiker]

Of course factors such as room size and listening habits are going to dictate how much power you need.  Near-field listening just doesn't make major power demands even with large dynamic swings.  Move into a large room, say 20 x 30 and unless you have efficient speakers, the power demands have just jumped.

However, even my HT setup in a 15 x 20 great room is handled by 120 watts x 5 / channel and can get louder cleanly than my ears want to handle.  How much power is enough?  Enough power to make your speakers sing and you smile is the correct answer.  For my 2 channel systems, it was outlined earlier in this thread. Light speed or "ridiculous speed" , whatever you & your wallet can handle......

Walt

[BobRex]

Geting back to the gist of your initial question, Roy Gregory started investigating the ability of an amp to project "authority" per a given output.  He used 3 conrad johnson amps of increasing capability and found that even at the same listening level (well within the performance envelope of the smallest amp (75 watts IIRC)) the more powerful amp projected with more authority, provided greater soundstage presentation, and just had more "there".  I always wondered if there was a frequency component to this "authority".  Would a 500w bass amp tied to a flea amp project the same?  How much power is needed above middle C to match the projection of a larger amp?

PS:  Yeah, I know room size, levels, sensitivities, absorption all come into play.  For discussion, consider all other factors to the equal.

[TONEPUB]

I agree with RG.  All things being equal, I'd rather have more power than less.  And I listen to a wide range of music, so it's essential.

As the Biker pointed out, (quite correctly) it's a lot about what your wallet will dictate.

[turkey]

Hey folks- Don't forget the first question: Have you found any correlation between wattage and sonic performance?

My amp has 220W/ch into 8ohms.

I have found that very low-powered and very high-powered amps seem to have issues. Still, I'd take a very high-powered amp over a flea-powered amp every time.

My speakers are fairly efficient (95 dB / 2.83 volt / 1 m), so my amp loafs. Last Fall I tried a 70 W/ch amp and it was quite adequate.

[werd]

Geting back to the gist of your initial question, Roy Gregory started investigating the ability of an amp to project "authority" per a given output.  He used 3 conrad johnson amps of increasing capability and found that even at the same listening level (well within the performance envelope of the smallest amp (75 watts IIRC)) the more powerful amp projected with more authority, provided greater soundstage presentation, and just had more "there".  I always wondered if there was a frequency component to this "authority".  Would a 500w bass amp tied to a flea amp project the same?  How much power is needed above middle C to match the projection of a larger amp?

PS:  Yeah, I know room size, levels, sensitivities, absorption all come into play.  For discussion, consider all other factors to the equal.

Yes to RG's assertion. Also its worth noting that in SS the higher you move in up a line it they typically offer more power. With these higher models you may get choke filtering, bigger transformers, and better output devices in transistors.

I am not sure if the bigger amps are only bandaid and covering up the real problem. The real problem being
AC delivery to your gear. I found that my Torus isolation transformer gave all my amps just way more jam. Including my 140 watt BC amp. Good AC in my experience can take the place of larger transformers in amps. But not the input filtering that seems to come with higher range amps or better output devices..... IME

[Wind Chaser]

At some point every speaker reaches its maximum output where it cannot generate any more sound pressure.  What's the point in pushing it with more power beyond that point? 

 

[werd]

At some point every speaker reaches its maximum output where it cannot generate any more sound pressure.  What's the point in pushing it with more power beyond that point? 

 

Hi WC

I don't think the OP's point was about SPL rather soundstage benefits of big power amps.... I don't go anywhere near the threshold of my speakers when i do my late nite listening.....

[bunky]

I run 93db loudspeakers with a 40 wpc class A single ended 6L6 tube power amplifier.it sounds fantastic....WCW III

[Niteshade]

This is the exact area I wanted to go in. Wattage can be an aid to reproducing the structure of a recording. AKA: The authority mentioned here. I often think of available power as a framework on which to build a sound stage on.

Geting back to the gist of your initial question, Roy Gregory started investigating the ability of an amp to project "authority" per a given output.  He used 3 conrad johnson amps of increasing capability and found that even at the same listening level (well within the performance envelope of the smallest amp (75 watts IIRC)) the more powerful amp projected with more authority, provided greater soundstage presentation, and just had more "there".  I always wondered if there was a frequency component to this "authority".  Would a 500w bass amp tied to a flea amp project the same?  How much power is needed above middle C to match the projection of a larger amp?

PS:  Yeah, I know room size, levels, sensitivities, absorption all come into play.  For discussion, consider all other factors to the equal.