Difference between 50,60,70....100 watts-->Bragging rights?

[tdamocles]

Kinda new to this stuff and have been reading...

Is it true that to double 'sound intensity' one must increase volume by 10db? Wouldn't that mean that to be twice as loud as say 100 watts you would need close to 1000 watts? Would that also mean that the difference between 75w and 100w is approximately 1.5db and would almost be undetectable? I could be wrong...correct me if I am.....

Is it all just marketing hype?

 

[T-Bone]

Kinda new to this stuff and have been reading...

Is it true that to double 'loudness' one must increase volume by 10db? Wouldn't that mean that to be twice as loud as say 100 watts you would need close to 1000 watts? Would that also mean that the difference between 75w and 100w is approximately 1.5db and would almost be undetectable? I could be wrong...correct me if I am.....

Is it all just marketing hype?

Yes, to double loudness loudness, one mut increase the power by 10X. Ears are able to discern a difference of 1 dB increments... so 1.5 dB is certainly detectable.

As for marketing hype, sort of!! 100W will yield about 1.5 dB difference compared to 75W... so focusing too much on that makes one fall for the hype. Not all watts are created equal... some watts are better than others

A good watt is one that was measured with low distortion... a bad watt might be so distorted that the signal is clipped (could danage the speakers).

One thing to remember when buying a receiver/amp: you want one that produces clean power, with the least amount of distortion. There are many other traits... keep reading this forum to find out more.

Oh, most folks don't upgrade their receiver/amp just to get a few dB more... they almost always upgrade because their current electronics has trouble driving their speakers, or they just want a more refined electronics system.

-T

 

[Tomorrow]

A good watt is one that was measured with low distortion... a bad watt might be so distorted that the signal is clipped (could danage the speakers).

Don'tcha just hate those watts when they start acting up and turn bad?! You suppose Georg Ohm used to say such things? LOL.

 

[Buckeyefan 1]

T-Bone: Oh, most folks don't upgrade their receiver/amp just to get a few dB more... they almost always upgrade because their current electronics has trouble driving their speakers, or they just want a more refined electronics system.

That is so true. If people would pay more attention to the speakers they purchase, they wouldn't have to drop big $$ on big watts. Klipsch speakers can run off an Ipod, while Maggies need plugged directly into an outlet.

When looking at watts, make sure you are comparing apples to apples. The better units are rated at full bandwidth which is 20-20,000 Hz, 8 ohms, and a reasonable distortion limit - say .05 thd. The weights of these units are also usually similar - unless you are looking at a digital class D or H type unit.

IMHO, you will realize a difference between a 75wpc, a 100wpc, and a 130wpc receiver - as long as it's a quality unit and the rest of the specs are the same. Don't be fooled by off brands. You usually get what you pay for. I'm still a proponent of weight. 33+ lbs usually means a quality mid level unit for a class a/b receiver. The benchmark is slowly moving towards 39lbs with the new Yamaha 2600 and Denon 3806 (brand new review in Sound and Vision Mag this month).

 

[tdamocles]

Yes, to double loudness loudness, one mut increase the power by 10X. Ears are able to discern a difference of 1 dB increments... so 1.5 dB is certainly detectable.

-T

Pulled from a web site - "A decibel is a single unit of sound, the first point on the decibel scale. But what makes up a unit?, a single decibel? One decibel is a relative measurement among people, it is the very limit of human hearing, the threshold point where sound can be detected by the ear and recognized by the brain. The noise produced by a single oak leaf falling to the ground is a single decibel."

Gotta have good ears to hear that....I agree with ya'll....

 

[xboxweasel]

It seems that a lot of multi channel amps are rated at 200W per channel. I have seen very few that exceed that. A 5 or 7 channel amp maxes out a 15A 115VAC dedicated outlet. And after 200w/channel the price goes up exponentially. I guess for a HT that's enough power considering the high efficiency of a lot of speakers now a days.

 

[mtrycrafts]

A good watt is one that was measured with low distortion... a bad watt might be so distorted that the signal is clipped (could danage the speakers).

If that is how you define watts. Highly unusual though.
How does a clipped signal damage speakers?
What if that clipped signal is on a CD?

 

[T-Bone]

A good watt is one that was measured with low distortion... a bad watt might be so distorted that the signal is clipped (could danage the speakers).[/b]

If that is how you define watts. Highly unusual though.
How does a clipped signal damage speakers?
What if that clipped signal is on a CD?

My comment about "good" watts vs "bad" watts was tongue-in-cheek... I was trying to make a point that not all signals, when measured, are equal, and I made the comment watt-centric (hence the good/bad thing).

As to your questions, you know how a clipped signal damages... you have 4000+ posts . Can a CD contains a clipped signal? Sure. I think they call those Rap CDs.

-T

 

[PENG]

As to your questions, you know how a clipped signal damages... you have 4000+ posts . Can a CD contains a clipped signal? Sure. I think they call those Rap CDs.

-T

How true! I think he deserved such cute answer this time hehehehehehe.............

That said, it's not a bad idea to clarify this so people don't think 1W (good or bad but 1 true watt electrically) can damage speakers (I mean tweeters in mid-fi and up speakers).

 

[T-Bone]

How true! I think he deserved such cute answer this time hehehehehehe.............

That said, it's not a bad idea to clarify this so people don't think 1W (good or bad but 1 true watt electrically) can damage speakers (I mean tweeters in mid-fi and up speakers).

Good point... a 1 W signal, either severely clipped or not, will not damage the drivers in a mid-fi speaker.... dare I say, even an entry level speaker.

To the OP, hope my original answer was not confusing.

-T

 

[majorloser]

Don'tcha just hate those watts when they start acting up and turn bad?! You suppose Georg Ohm used to say such things? LOL.

Bad watts,
Bad Watts,
Watcha gonna do?
Watcha gonna do when they come for you?

"Audioholics is filmed live with the men and women of audio enforcement. All watts are innocent until proven guilty in a court of law."

 

[mtrycrafts]

My comment about "good" watts vs "bad" watts was tongue-in-cheek... I was trying to make a point that not all signals, when measured, are equal, and I made the comment watt-centric (hence the good/bad thing).

As to your questions, you know how a clipped signal damages... you have 4000+ posts . Can a CD contains a clipped signal? Sure. I think they call those Rap CDs.

-T

Yes, I think I know about what damages a speaker, or one driver more than the other. Does the poster you responded to know? As you posted, not all clipped signals will damage the speaker, hence a generalization is inappropriate here. And, it is not the clipping that damages but the power, hence the comment about the clipped signals on a CD not damaging speakers, just ones ears.

Having lots of posts is also not a good indicator of ones knowledge

 

[ht_addict]

And, it is not the clipping that damages but the power, hence the comment about the clipped signals on a CD not damaging speakers, just ones ears.

Having lots of posts is also not a good indicator of ones knowledge

Don't power/clipping go hand in hand If the amp tries to put out the appropriate power, yet runs out of voltage from the supply rails we will get a flat spot at the upper and lower peaks of the wave form. In a severe case of clipping, there is so much additional energy buildup (heat) into the voice coil(s), but the cone does not move (motivate) enough to cool the voice coil and former adequately. Hense, the voice coil over heats and either seizes in the gap or burns the voice coil windings. Burn baby burn.

 

[agarwalro]

The empetus behind getting a higher (and higher and higher... ) powered amplifier is not the ability to driver the speaker, but the ease, grace and for the want of a better word, clean-ness with with it can drive it.

Think of it as being able to pick up a 50 pound box. The stronger you are, the more easily you can pick it up and the longer you can hold it up. If you get stronger, at some point you will be able to pick it up with one hand. If you get stronger still, you will easily be able to pick it up with one hand... then what? Time to get a heavier box... Bigger speakers

 

[mtrycrafts]

Don't power/clipping go hand in hand

If the amp tries to put out the appropriate power, yet runs out of voltage from the supply rails we will get a flat spot at the upper and lower peaks of the wave form. In a severe case of clipping, there is so much additional energy buildup (heat) into the voice coil(s), but the cone does not move (motivate) enough to cool the voice coil and former adequately. Hense, the voice coil over heats and either seizes in the gap or burns the voice coil windings. Burn baby burn.

The amp clips when you exceed its rated power output, or try to ask for more than it can. So, a rated 100 watt amp will start clipping somewhere around that number. The power output will be increasing to twice its RMS value. If the low driver cannot handle that power continuously, yes, it will be damaged. But, if that driver can handle that power, it will not matter to that driver if it is from clipped power or not. So, in the end, it is the power that destroys the speaker just as if you placed a 400 watt amp in there and delivered clean power beyond the speaker's rated value.

 

[mtrycrafts]

The empetus behind getting a higher (and higher and higher... ) powered amplifier is not the ability to driver the speaker, but the ease, grace and for the want of a better word, clean-ness with with it can drive it.

That amp doesn't care if it puts out 1 watts or its RMS rated power and it will be as clean as that rated output spec is before it starts clipping.

 

[Buckeyefan 1]

That amp doesn't care if it puts out 1 watts or its RMS rated power and it will be as clean as that rated output spec is before it starts clipping.

Well.....

Sometimes there are VU meters that post the output wattage (lets assume they are accurate), and those can be misleading. 10 watts through a K-Mart amp may be at a much higher distortion level than 10 watts through a Yamaha amp - given the same speakers. You may be at exactly the same dB's, but the sound could be totally different because of distortion (no clipping). Yes, the amp has no idea, but we can track the output in wattage.

 

[Buckeyefan 1]

Don't power/clipping go hand in hand If the amp tries to put out the appropriate power, yet runs out of voltage from the supply rails we will get a flat spot at the upper and lower peaks of the wave form. In a severe case of clipping, there is so much additional energy buildup (heat) into the voice coil(s), but the cone does not move (motivate) enough to cool the voice coil and former adequately. Hense, the voice coil over heats and either seizes in the gap or burns the voice coil windings. Burn baby burn.

As long as you are talking about woofers, you are pretty much correct. In properly built speakers, the crossovers filter out the damaging energy to the mids and tweets. All the speaker sees is really fast pulsed dc.

 

[Nick250]

Well.....

Sometimes there are VU meters that post the output wattage (lets assume they are accurate), and those can be misleading. 10 watts through a K-Mart amp may be at a much higher distortion level than 10 watts through a Yamaha amp - given the same speakers. You may be at exactly the same dB's, but the sound could be totally different because of distortion (no clipping). Yes, the amp has no idea, but we can track the output in wattage.

I wonder if we may need to rethink entry level receivers. The Pioneer VSX 516 for $199 got a decent review here on AH. A real life competent AV receiver for $199 list price!

http://www.audioholics.com/productreviews/avhardware/pioneer-VSX-516p1.php

A few months back I purchased a Denon 1705 brand new in the box from Tweeter for $228 on closeout since my Onkyo had just died. It filled in as my main AV receiver powering the system in my sig below for about a month until I got the 3806. It played loud and clean and is heck of a good receiver (now doing able stereo duty in the den powering Paradigm Mini Monitors). I think we need to reconsider our bias against lower end electronics. In many cases it's probably not justified. Not main stream thinking, I know, but I think it has merit.

Regards, Nick

[Edit] Snippy part of post removed.

 

[Stringreen]

How clipped amps burn speakers

If you picture a wave, you can imagine an anchored rowboat rising and falling with the passing of the wave. As a storm is brewing the rising and falling of the boat creats a larger up and down rocking of the boat. This is what happens when the electrical waveforms drives a speaker. When an amplifier clips, the power supply of the amp can't drive the wave properly. It can provide a leading edge, but can't go to the top of the wave. The wave is then flattend. the speaker cone is driven outward, and stays out waiting for the amp to provide the falling edge of the wave. All the energy of keeping the cone "out" turns to heat and burns the voice coil. Sometimes the amp can clip to such extremes that it can actually go completely out of control and ocillate - burn it all.