Watts what exactly is the sound quality difference?

[Smokey]

3) To answer your question in plain English, watts has NOTHING to do with sound quality. Zip. Zero. Zilch. Nada.

Sorry, but that statement is not "politically" correct. If you don't have enough power to reproduced music peaks faithfully, then nothing else matter because distortion (mainly clipping) will be introduced into the system...which we can't get rid of.

Having ample power in a system is like having a good foundation for a house. You will need a solid foundation to build on, or the house will come crumbling down at the first sign of weather disaster a.k.a. music clipping

[N. Abstentia]

Policitally correct or not, it's the correct answer.

What does 20 watts sound like?

Can't answer, can you? That's why I say "watts has nothing to do with sound quality".

[Smokey]

Well, lets look at it this way....

Setup a 20 watt and an 100 watt system and then compare the sound quality of both. Initially at low volume level, both systems will sound the same. But as you get slightly louder, as [listening] time wavers on, you note a slight listening fatigue while listening to lower power system. And the fatigue is cause by [low power] amplifier clipping music passages that are reaching up to couple of hundred watts momentary.

Another example that will demonstrate clipping better would be with a car stereo system. If you turn up a volume on a low powered car stere (as I am sure all of us have done), one will note that as volume is increase, there will be more gargle distorted sound coming out of speakers. The gargle sound is caused by clipping due the fact the amplifier don't have enough juice to reproduced high power music peaks.

Here is a picture of wave form from two amplifiers:


Although both amplifiers might have the same power ratings, but the right figure doesn't look anything like the left figure. So an amplifier that produce the right figure is labeled as high THD% (total harmonic distortion) amplifier (fatigue listening), while the amplifier that produces the left wave form is labeled as low THD amplifier albeit both amplifiers having the same power ratings.

So it is always recommended to buy highest power amplifier with the lowest THD% figure

[Geoffcin]

Thanks for the link which I went to. A few questions for you. I play my system in an average size living room in an apartment complex, therefore it is imperative that I do not have a "booming" bass that causes vibrations and annoys neighbors- personally I do not like the bass to be prominent and/or overbearing, just prefer it being subtle so I can hear bass guitar notes blending in with the rest of the sound. They say in the link that this is "room shaking bass". Won't this then by innapropriate for listening in an apartment especially for someone like me who does not want to be overpowered by bass? Also, in regards to speakers, if my receiver plays 220 watts or so, and other speakers are say 100 watts each speaker, won't those speakers be innappropriate for a 220 watt reciever?

The answer is YES, you will have control over how much bass your sub puts out. For HT, the ability to "shake the room" is nessasary for the low frequancy effects to be rendered correctly. You do not have to set you sub to that lever for audio.

Your reciever will not be to much power for these speakers at all.

[N. Abstentia]

Well, lets look at it this way....

Setup a 20 watt and an 100 watt system and then compare the sound quality of both. Initially at low volume level, both systems will sound the same. But as you get slightly louder, as [listening] time wavers on, you note a slight listening fatigue while listening to lower power system. And the fatigue is cause by [low power] amplifier clipping music passages that are reaching up to couple of hundred watts momentary.

Hmm..I don't know if I can agree with that. I'll guarantee you that I can take a 20 watt amp made by Linn or Levinson or Arcam or something like that, put it up against a Sears system that says '100 watts' on the front and my 20 watt system will leave it in the dust.

Now I know you're assuming all things are equal with your post, but the original poster is not. He just asked (something like) "will a 400 watt system sound better than a 100 watt system?" You just can't answer that question.

[mtrycraft]

Hmm..I don't know if I can agree with that. I'll guarantee you that I can take a 20 watt amp made by Linn or Levinson or Arcam or something like that, put it up against a Sears system that says '100 watts' on the front and my 20 watt system will leave it in the dust..

Maybe yes, maybe no. You are speculation of course or you would not have claimed this.

[Rodzilla]

oh i think he's "likely" right...things have gotten abysmal with regards to published specs...how many HT amps say 100 wattsx5 on them?have a looksee on the back panel..if the power consumption ain't 500 watts or more it really just ain't doin it,no way,no how,not in all channels at once at least,you can't put out more than you take in...[how many people just looked and went "ahhhcrap!"???]theres a lot of 5x100 watt HT receivers out there with about 150-200 watt power consumption ratings...these ratings are true,they have to be to get UL and CSA approval

i have a sherwood reciever that claims 35/ch...power consumption is rated at bang on 70watts...it's likely putting out about 10-15 real watts continous,considering that the amp makes heat and does other stuff besides amplify...that's all coming out of the 70 going in,it actually can't put out 35w/ch into any load ..i also have an NAD 304 int. it also claims 35/ch but it's power consumption is well over 200 watts...you wanna tell me they sound the same?not hardly!both are rated for 4 ohm loads but even at low volumes where neither should be working the NAD will absolutely clean the floor with the sherwood in sound quality and dynamics....it does put out 35/ch and has 5.5db of short term headroom besides..it's not so much the quality of those watts but the fact that you actually do have them on tap,not just on paper...and computer speaker's amp ratings???they come from some alternate universe..apparently

smokey..thd ain't what you're talking about there,thd is "total harmonic distortion"...it's noise that the amp is adding to the output at some multiple of the original signal[harmonics]it's vanishingly low in almost all modern amplifiers...clipping is just exceeding the amps power supply...when the output voltage swing goes higher than the voltage on the PS rails...it can't get any higher,you run out of juice and you get the waveform you're showing,you're asking the amp for more than it's got...and it'll try anyway...if you increase the voltage on the rails[+vc,-vc wider apart]you'll actually get it and a higher powered amp in the process...a modern amp should shut off putting out that sort of stuff...you're basically feeding the power supply voltage to your speakers and the protection relay "should" kick out if the circuit has been designed properly,DC voltage will cook your speakers in a hurry

[Smokey]

How many HT amps say 100 wattsx5 on them? Have a look and see on the back panel..if the power consumption ain't 500 watts or more it really just ain't doing it, no way, no how, not in all channels at once at least. You can't put out more than you take in.

You have to realize that power rating into speaker is different than the consumption power rating on its back panel. The channel power ratings are refer to as "apparent" power (which mean not all of it is consumed)-because the speaker is an inductive load. But the consumption power [from AC cord] is refer to as "real" power (all of it is consumed). So most of time, they will not match up. You might have 100x5 watt power rating, but consumption power will be less than 500 watt.

I have a sherwood receiver that claims 35/ch...power consumption is rated at bang on 70watts....I also have an NAD 304 int. it also claims 35/ch but it's power consumption is well over 200 watts...you wanna tell me they sound the same?

As it was said before, you also have to take into account Dynamic Headroom and THD rating of amplifier. If they are not equal in those department also, of course they will not sound the same. Sherwood probably can put out as much as power as NAD, but with much higher THD distortion rating. If you look at computer speaker power ratings, most of them are rated well over 100 watt. But the catch here is that their THD are high also (such as 10% THD).

So a 100 watt amplifier with high THD will sound like crap when compared with a 100 watt amplifier with low THD rating (preferably below 0.3 percent).

Smokey, THD ain't what you're talking about there. THD is "total harmonic distortion"...it's noise that the amp is adding to the output at some multiple of the original signal [harmonics]. it's vanishingly low in almost all modern amplifiers...clipping is just exceeding the amps power supply.

You statement about THD-meaning adding harmonics to original signal is correct. So going from there, a clipped signal will also add harmonics to original signal since clipped signal resemble a square wave. And square waves are full of harmonics. That is why when amplifier is pushed beyond it rated output, its THD will increased due to the fact that clipped signal is adding unwanted harmonic into the original signal

[jackz4000]

With a good ear, one will "hear" the difference in quality and pure junk equipment. Also, AC power consumption from the AC plug is not the same as the rms output of an amplifier or receiver.

Once upon a time in the Stereo world there were specific measurements of an amp mandated by the FTC. Standards. At that time, Stereo was the "big wave" that everyone wanted to catch. Everyone was going to buy into Stereo. There were alot of "junk" peddlers too. And there were companies striving to build the absolute best. Because at the time there were so many unscrupulous manufacturers making incredible claims in regard to wattage output and distortion. "Peak Power". That FTC standard became the standard for all the reputable audio manufacturers at the time and for the consumer.... it gave a "standard" to help measure products. It was a good aid to the consumer in the stereo days. I still think the ear is the best.

HT is now the new "big wave" for manufacturers to catch. Everyone is going to have an HT rig. From NY to Omaha. From the USA to Malasyia. It's like a goldrush. It is a goldrush. Its a dollars and cents thing. It's biz and margins. Profit and loss. There is big money to be made within this window of opportunity. With HT, there are no real FTC standards, like there were with Stereo, except for the standards a manufacturer will use to best market their product. A couple tech's who work at big reputable companies have told me that their companies HT specs are measured in such a way as to inflate the # 's for the best marketing # 's. They were not thrilled, but the word comes down from up top. And they want to keep their jobs.

Anyway, the quality will all be in the build of the amp or pre-amp section. And then the speakers. It will all be up to the manufacturer to decide just what the build will be. The cost out and the selling price. And there are great quality manufacturers out there who do a solid build. Quality is timeless...you hear it with you very own ears. Usually quality will cost more.

Today most wattage and THD # 's can be almost comical. Last month, with a friend we stopped by the home of his friend to drop a couple things off. It became comical 'cuz the guy just HAD to show us the HT set-up he had put together....for $6000. He just had to impress me. He had devoted his whole living room to it...it was like a shrine. His wife has demanded a new addition, a new living room and it's being built. I really wanted to go. After politely listening for 15 minutes we left. The big TV he got for $2000 and $4000 he spent for audio.

As we pulled away, I had to laugh and mentioned it's a good thing the guys a plumber, 'cuz he doesn't know a thing about sound. For $4000, he gave alot of money away. But, he is happy. Absolutely thrilled. I know I wouldn't be. " It's 800 watts". Lotta BIG # 's in the supposed wattage....but, he got taken in by the HT goldrush. Why? Because he knew next to nothing about amps and sound, which with that knowledge would have yielded him a much better set-up for 1/2 the price. Watts? Its all in the quality of the build.

[mtrycraft]

oh i think he's "likely" right...things have gotten abysmal with regards to published specs...how many HT amps say 100 wattsx5 on them?have a looksee on the back panel..if the power consumption ain't 500 watts or more it really just ain't doin it,no way,no how,not in all channels at once at least,you can't put out more than you take in...[how many people just looked and went "ahhhcrap!"???]theres a lot of 5x100 watt HT receivers out there with about 150-200 watt power consumption ratings...these ratings are true,they have to be to get UL and CSA approval

Perhaps if one doesn't understand what is written, in this case 5X100 watta, or 100 qatts X 5, then one should ask questions. Many assume that this rating is all channels driver at the same time, right? That is not what the spec states. It states each channel can output 100 watts. When do you need 100 watts at the same time? Which music or movie?

i have a sherwood reciever that claims 35/ch...power consumption is rated at bang on 70watts...it's likely putting out about 10-15 real watts continous,


Do you have evidence of this? If so, write to FTC and tell them that Sherwood is lying and breaking the advertisement rules and amp rating standards.

it actually can't put out 35w/ch into any load .

You know this because you bench tested this unit?

.i also have an NAD 304 int. it also claims 35/ch but it's power consumption is well over 200 watts.

How do you know this? The label on the back? Try again, that ain't it.

..you wanna tell me they sound the same?

Well, only a DBT will tell you one way or the other. But existing evidence would indicate this as long as you don't exceed the design specs. You have evidence to support your proposition?


both are rated for 4 ohm loads but even at low volumes where neither should be working the NAD will absolutely clean the floor with the sherwood in sound quality and dynamics...

That is your speculation not supported by evidence. I understand your supposition unsuported.

.it does put out 35/ch and has 5.5db of short term headroom besides.

Is that in the specs? But you said it means nothing. Or just the ones you dislike for some reason?


and computer speaker's amp ratings???they come from some alternate universe..apparently

If that is what it is, perhaps yes.

[mtrycraft]

Once upon a time in the Stereo world there were specific measurements of an amp mandated by the FTC. Standards.

This standard has not been cancelled it is still in force.

HT is now the new "big wave" for manufacturers to catch. Everyone is going to have an HT rig. From NY to Omaha. From the USA to Malasyia. It's like a goldrush. It is a goldrush. Its a dollars and cents thing. It's biz and margins. Profit and loss. There is big money to be made within this window of opportunity. With HT, there are no real FTC standards, like there were with Stereo, except for the standards a manufacturer will use to best market their product.

FTC has not updated the specs to standardize multi channel amps. The old standard is still in force when you rate for two channel operation.
And, most tested models do perform to their claimed power into 2 channel simultaneou operation.



For $4000, he gave alot of money away. But, he is happy.

I should hope so. He bought it to please himself only, no one else, right?

[gonefishin]

Hmmm...while you guys bring up several good pints of discussion.


Smokey, your sure right that you don't want to push your amps into clipping. If a persons system is clipping during normal use...They simply need to get...either a new amp, new speakers or turn the volume down. In this clipping situation there is little use talking about sound quality of the amp or system. Because neither the amp or system is operating within it's intended use.

But I think a better way to talk about Watts, would be to say that...Watts are relative. They are relative to the speakers you are using, They are relative to the room and They are relative to your listening preferences. While you certainly don't want any gross mismatch in your system(clipping), a general recommendation on how many Watts will work best for all people cannot be given. So...generic numeric Watt recommendations are useless, not necessarily Watts themselves.


have fun!

[jackz4000]

mmtrycraft, Yes, still in effect. A pretty good standard too.

Yes, again. I would think most reputable manufacturers will list their 2 channel specs appropiately. ie: 20-20K, 100 rms watts per channel both channels driven @ 8 ohms w/0.05% thd or 1% thd. Its the other 3, 4 or 5 channels. Then we have the one channel driven # 's or 150 watts at 1khz. Lotta people (nobody here) see that watt # and thats all they see. Kinda funny. So many people without a basic audio understanding, just go by the biggest watt #.

The plumber. Yeah, he was so thrilled with "800 watts" that I just hadda go and make sure I didn't say anything to let him think otherwise....for $4000 he blew plus the wife's new living room in progress, my lips are sealed. He is now going to get a sub, that will probably be a gigawatt or 2. I think he will become a more expensive plumber.

I got a friend I work with, nice guy, wife, 2 kids and the whole package. Knows not much about audio. Just bought a HT set-up. He is thrilled too 'cuz that new $225 Pioneer is "500 watts." There are watts and then there are...watts.

[Smokey]

But I think a better way to talk about Watts, would be to say that...Watts are relative. They are relative to the speakers you are using, They are relative to the room and They are relative to your listening preferences.

Hey GF, glad you still hanging around these parts.

I do agree with your statement. Somebody that own a Klipsch speaker might not need as much as power a person that have Magneplanar speakers that have lower sensitivity. But as general middle of road guide, it might be good advice to buy highest power (with lowest THD) amplifier one's budget allows. There is no such a thing as having too much power

I found the spoon.

I hope you put it back, or Eyespy will be furious