"Headroom" - what does it sound like to you?

[sfogg]

"I'll bet someone's 60 watt amp sounds "louder" than my 325-watt amp. Mine will sound more powerful. Read the article."

I've read the article.

Why don't you read other articles... such as....

http://www.smr-home-theatre.org/Power/Power-How-Much.html

And take the numbers for the 99dB speakers and divide them in half for a speaker that is 102dB efficient. Cut that number in half again for a 105dB efficient speaker.

Or for a driver that is 109dB efficient divide the required wattage by 10.

If you aren't clipping the amp you aren't loosing dynamics from it.

As far as distortion goes I have measured the distortion in my system from end to end at various frequencies and power levels.

Have you?

It has been my experience that the room has far more of an influence on when something sounds 'too loud' then an amp that isn't clipping does.

Shawn

[Jeff Matthews]

And folks, if you'd bother to read and learn, you'd see that the theory does not only apply at ridiculously high outputs. A 150 watt boom through your woofer is not exactly ear-splitting.

If you cranked your 60-watter, you'd lose out on those peaks. If you cranked your 40-watter, you'd also lose out on similarly-higher peaks. You lose dynamics without remotely realizing that with more power, it would not necessarily sound "louder," it would sound more dynamic and powerful.

That's okay, though, guys. Just keep on thinking you get all the "loud" you want out of 40-watts. I'm sure you do.

When you finally get a taste of "power" versus "loud," you'll understand. But as long as you equate "power" with "loud," you'll be "satisfied" that you just don't need any "louder."

[Deang]

What Shawn's been saying.

Jeff, from the beginning of the article:

"...we concluded that using a pair of M80ti speakers at a distance of 12 feet in an average room, and attempting to reproduce the 109-dB peak sound pressure levels of a grand piano playing crescendos, would require an amplifier capable of at least 200 watts per channel output to handle the musical peaks."

It's a good article on the subject. However, the loudspeaker in the example is the Axiom M80ti, which has an in-room sensitivity of 95dB. With this in mind, and applying the same method of calculating to Heritage -- you need 20 watts (twice as sensitive = 10 x less power). This of course presumes you want or need peaks of 110dB at the listening position. Hey, that's damn loud.

[Jeff Matthews]

"I'll bet someone's 60 watt amp sounds "louder" than my 325-watt amp. Mine will sound more powerful. Read the article." I've read the article. Why don't you read other articles... such as.... http://www.smr-home-theatre.org/Power/Power-How-Much.html And take the numbers for the 99dB speakers and divide them in half for a speaker that is 102dB efficient. Cut that number in half again for a 105dB efficient speaker. Or for a driver that is 109dB efficient divide the required wattage by 10. If you aren't clipping the amp you aren't loosing dynamics from it. As far as distortion goes I have measured the distortion in my system from end to end at various frequencies and power levels. Have you? It has been my experience that the room has far more of an influence on when something sounds 'too loud' then an amp that isn't clipping does. Shawn

Shawn, here's a quote from your article:

"What do I need a bigger amplifier for? Mine already plays loud enough to hurt my ears!" Of course, he pointed out that a big enough amplifier will play loudly without hurting your ears."

That's my point, too! I'll add, since your article is rather brief, that a big enough amplifier will play at even higher volumes and "hurt" your ears less than a lower-powered amp.

[maxg]

Just as a matter of interest how sensitive are the speakers the writer in your link is using?

"If your speakers are 3 dB less sensitive than the M80ti's, or you are another three feet back, then twice as much power (400 watts) again would be needed to hit that goal of 109 dB SPL. It doesn't tax our arithmetic skills to realize that aiming for rock concert peak sound levels of 115 dB (if the neighbors could stand it), is beyond our capabilities. Most of our amplifiers and receivers do not have enough dynamic headroom to deliver this kind of power output without sounding strained. (To finish the example, using M80ti's to reach 115 dB at 12 feet would require 6 dB more output, or four times the power that the 109-dB level required, so 800 watts per channel would be needed.) "

Shall we guess 93 dB? So to do the same with a Khorn - with 11 dB sensitivity advantage takes how much power? I guess about 60-70 wpc - and that is for the peaks (note the highlighted section).

Therefore a 50 watt amp with a miserly 3 dB headroom can comfortably do the job without clipping - or am I missing something?

[sfogg]

"If you cranked your 40-watter, you'd also lose out on similarly-higher peaks. "

The whole point is cranking a 40 watter results in an SPL level (120dB) far above what most would listen at.

Soooo IOW, the amp won't be cranked.

Therefor it won't be straining.

Therefor it won't be distorting.

Therefor it won't be an issue.

The difference between a 40w amplifier and a 400w amplifier is all of 10dB. If one isn't listening at 120dB they sure as hell aren't going to be listening at 130dB either.

Shawn

[Allan Songer]

When you finally get a taste of "power" versus "loud," you'll understand. But as long as you equate "power" with "loud," you'll be "satisfied" that you just don't need any "louder."

The worst sounding "hi fi" I ever heard consisted of a 400 watt Phase Linear amp with matching preamp driving a pair of Altec A7 "Voice of the Theater" speakers. SURE it played LOUD, but it was one of the most unmusical sounding abominations I have ever been subjected to.

[Jeff Matthews]

What Shawn's been saying.

Jeff, from the beginning of the article:

"...we concluded that using a pair of M80ti speakers at a distance of 12 feet in an average room, and attempting to reproduce the 109-dB peak sound pressure levels of a grand piano playing crescendos, would require an amplifier capable of at least 200 watts per channel output to handle the musical peaks."

It's a good article on the subject. However, the loudspeaker in the example is the Axiom M80ti, which has an in-room sensitivity of 95dB. With this in mind, and applying the same method of calculating to Heritage -- you need 20 watts (twice as sensitive = 10 x less power). This of course presumes you want or need peaks of 110dB at the listening position. Hey, that's damn loud.

DeanG, I don't think in terms of dB when I listen to music and never have. I wouldn't know if I'm at 80, 100, 110, 120, nor have I ever bothered to care. My listening habits are to play at what volume I'm in the mood for. And when I'm in the mood to turn it up loud, I've definitely, most positively, absolutely, hands down, seen a difference between night and day between my long-gone 90-watt Marantz and my 325 watt Crown.

The difference is smoother listening with greater dynamics. Whatever dB that is does not matter to me.

[sfogg]

"here's a quote from your article:"

Here are some others that aren't just in the introduction to the article...

"Second, for someone who never listens above moderate levels, 20 watts per channel will be enough for even the most inefficient speakers."

"The 116 dB given as the maximum peak level represents what you'll encounter at an actual concert. But in most rock the peak and average levels are very close, so that the corresponding average level would be around 110 dB. Most people can't play their systems at those levels because neither their neighbors nor their loudspeakers will stand it. If you must have such levels despite the inevitable hearing damage they will cause, you should achieve them not by buying a bigger amplifier but with special loudspeakers, which is our next subtopic."

" a speaker that puts out 99 dB at 1 meter with one watt of input will play as loud with a 3-watt amplifier as an 81-dB/w/m speaker with a 200-watt amp. If you must hear classical music at realistic levels, it's pretty obvious that a more efficient speaker can spell the difference between success and failure. "

" (like Klipschorns) which are more efficient by an additional 5 dB, and all such speakers can produce very high sound levels with a modest amplifier."

Again... have you ever measured the end to end distortion in your system at various playback levels at various frequencies?

Shawn

[Deang]

Jeff, I think you're off-base too a bit. You posted the link to the article and somehow missed the point of it. "Headroom" expands dynamic range because dynamic peaks aren't clipped. If I use a 20 watt amplifier, I can do 110dB peaks at the listening position -- clean and undistorted. My dynamic range will be the difference between my noise floor and the peaks. However, this assumes a recording that isn't compressed into nothingness.

[maxg]

What Shawn's been saying.

Jeff, from the beginning of the article:

"...we concluded that using a pair of M80ti speakers at a distance of 12 feet in an average room, and attempting to reproduce the 109-dB peak sound pressure levels of a grand piano playing crescendos, would require an amplifier capable of at least 200 watts per channel output to handle the musical peaks."

It's a good article on the subject. However, the loudspeaker in the example is the Axiom M80ti, which has an in-room sensitivity of 95dB. With this in mind, and applying the same method of calculating to Heritage -- you need 20 watts (twice as sensitive = 10 x less power). This of course presumes you want or need peaks of 110dB at the listening position. Hey, that's damn loud.

Tee hee.

When I first saw your post - made at the same time as mine, I thought - oh sh1t - I got the maths wrong somewhere - then I saw you were reaching for 110 dB at the listening position and I was going for 115. That means our numbers pan out - which is nice to know. I did get a bit higher - but only because I assumed a 93 dB efficiency rather than 95.

[Deang]

"I've definitely, most positively, absolutely, hands down, seen a difference between night and day between my long-gone 90-watt Marantz and my 325 watt Crown."

Uh oh -- you've taken this into a different direction now. You are presuming all 90 watt amplifiers sound and behave the same. Bad Jeffery, bad bad bad.

[Jeff Matthews]

Dean, no, I didn't want to imply all 90-watters are the same, but I had a very good Marantz integrated amp/pre-amp. It was an 1180DC. You could probably Google the specs and tell me how to decipher them and how crappy it was, but seriously, it was a very good amp.

In the end, guys, I guess I just listen at higher outputs than you, and I need the amp that lets me do it.

We may be talking about entirely the same thing, with the only difference being what outputs we want. However, I feel gratified to some degree in that this "theory" started out being debunked, but it now appears people are finally buying it as the science it is.

A big question would be where, typically, on your volume knob will you begin to start losing the dynamics? I've seen that it often appears around just over half-way up to around 2/3's where amps begin to suffer.

[sfogg]

"In the end, guys, I guess I just listen at higher outputs than you, and I need the amp that lets me do it."

Without you having any idea at how loud you listen that may be a reach. Go buy a $40 SPL meter sometime....

"A big question would be where, typically, on your volume knob will you begin to start losing the dynamics? "

That is totally meaningless. The volume control on most equipment has absolutely no reference point at all to the power being put out or to the SPL level in the room.

Unless you have equipment that allows you to calibrate your volume control, mine does, the above is meaningless.

Shawn

[mobile homeless]

Dr. Who, I just spent some time with Nightwish.... my first reaction was, is this the new millennium's Spinal Tap?

My second reaction after I got over the music was how different we view recording attributes. I think these selections represent examples of some of the horrors of recording but do realize we're talking MP3 versions. If you could load a WAV file, of two of the songs off this last album, I'll give it a go. As is, songs like "Dark Chest of Wonders" leave me shaking my head on several fronts. We are talking totally different perceptions of quality. This is one of the most sterile, pumped up, artificial, mediocre recordings I have heard in awhile.

After listening to one of the 192kbs MP3 from each of the albums, I came away realizing that no qualifiers are being used here.

When making assessments on gear attributes, you MUST realize the variables and limitations and list these qualifiers when making judgments. This has been the bain of this forum's existance. I now have a much better idea of where you're coming from. Dean used to do this with Mudvein.....heh.

kh

[Jeff Matthews]

Jeff, I think you're off-base too a bit. You posted the link to the article and somehow missed the point of it. "Headroom" expands dynamic range because dynamic peaks aren't clipped. If I use a 20 watt amplifier, I can do 110dB peaks at the listening position -- clean and undistorted. My dynamic range will be the difference between my noise floor and the peaks. However, this assumes a recording that isn't compressed into nothingness.

Dean, I will add that if you're running a 20-watt amp at its full 20, you're clipping. Gotta leave some very substantial room. So, that's where all you guys' figures are off. Your figures all assume playing a rated amp at its full open rating. That's a no-no.

[sfogg]

Dean,

" If I use a 20 watt amplifier, I can do 110dB peaks at the listening position -- clean and undistorted. My dynamic range will be the difference between my noise floor and the peaks."

Bravo! So few people realize the signifigance of the above......

Shawn

[Jeff Matthews]

Shawn, I beat you. Read my prior post.

[sfogg]

" I will add that if you're running a 20-watt amp at its full 20, you're clipping. Gotta leave some very substantial room. So, that's where all you guys' figures are off. Your figures all assume playing a rated amp at its full open rating. That's a no-no. "

Re-read what Dean wrote... he said *peaks* at 110dB. IOW he already is leaving plenty of room.

For a recording with 10dB of dyanmic range between average and peak (and many current CDs don't even have that) that would mean the average level is 100dB.

That would be considered very loud to most people. The average listening level is more likely around 70-90dB.

If we split the difference and say 80dB average playback the recoridng would need a 30dB difference between the average level and the peak level before the 20w amp would run out of steam.

You would be hard pressed to find may with that sort of difference between average and peak levels. The most likely place to find that would be in movies as they still understand the importance of dynamic range.

Shawn

[maxg]

"If we split the difference and say 80dB average playback the recoridng would need a 30dB difference between the average level and the peak level before the 20w amp would run out of steam. "

And the above does not mean a dynamic range of 30 dB. If the quiet parts of the recording were, for argument's sake 50 dB it would have a dynamic range of 60 dB.

Bloody rare!! On any medium.

And we are assuming no headroom built into said 20 watt amp. If, as quoted in the link from Jeff, the amp has 3 dB headroom you STILL do not have a problem.

There is one more thing, however, that might explain Jeff's penchant for big bruiser amps and that is if he has a very large listening room and sits well back. You can drop as much as 6 dB/meter in a typical room so if you are 5 meters away from the speakers you would need additional power over the 20 watts Dean mentioned.