How Often Does Brand "X" Receiver Not Live Up To Power Specs? (1 Viewer)

[Charles M Berry]

All of the data listed in the chart below was obtained from this spread sheet located at this web site
What I have done is to compare the Manufacturer's published power rating (watts per channel), to the measured (or actual) max output before distortion. Based on this data, I created a ratio for each receiver/amp that can be used to quickly identify how close a particular model's actual output is claimed in advertising.
The reason why I created this chart is not to look at individual models per say, but to see if certain manufacturers have a habit of inflating the amount of power their receivers can deliver per channel. I did this for educational purposes only!
I have only included major companies with more than a single model with data available in the original chart.
HERE IS THE CHART
While there is no absolute conclusion, it seems that from the above chart, information published by Harman Kardon about their product's abilities can be trusted with a high level of confidence. Likewise, someone interested in purchasing a receiver from Kenwood might want to be weary of the products published specs on "watts per channel", as Kenwood seems to inflate these figures.
If I have screwed this up, please let me know. I hope this is interesting and helpful, and not redundant, as I spent alot of time making this!

 

[Nick Cerretti]

Why do you single Kenwood out? Pretty much every company listed have inflated power ratings?

I don't get why people get so pissed off on this wattage issue. Companies do correctly rate their equipment (its just not running 5 channels, at 8 ohms, at 20-20khz, which I guess is the standard to look for). Some only do it with 1 speaker, 2, etc.

This is a very competitive market, and these companies need to do as much as possible to win consumers, especially the "i have no idea what I'm doing" consumer. I imagine H/K loses plenty of sales to unknowlegdable consumers because of this.

 

[Charles M Berry]

I don't get why people get so pissed off on this wattage issue.

Nick, I am not pissed off in the least. Did my original post have a pissed off tone?

 

[Nick Cerretti]

Charles,
No, that wasn't meant for you. I got stuck in a Dennis Miller-esque "I don't want to get into a rant here..." speech. I guess it was a statement to the board or something..:rolleyes

 

[Frank Carter]

Thanks for the info

 

[Wayne Ernst]

I didn't feel that this individual was singling Kenwood out. However, he did point out that Kenwood appeared to be one of the biggest violators. Yes, each manufacturer does inflate their results to a degree. However, if a manufacturer states that their receiver puts out 100 watts per channel with all channels driven, then S&V tests the receiver and determines that it's actually 50 watts per channel with all channels driven - then the manufacturer is clearly lying. This happens to be the scenario in quite a few cases. If the manufacturer could clearly indicate with "1 channel driven" - some consumers could clearly realize this, while others may not.
But, things get even more foggy when retailer such as Best Buy reprint the specs on their own tags. The tags tend to vary a little bit from what the original manufacturer intended to state - and this tends to throw of the perception of the consumer even more, unfortunately. :frowning:

 

[DanielSmi]

There's two points that makes this comparasion unbalnced. First different brands use different clipping points than what S&V uses so who's to say they don't meet their own defined power ratings; there is no standard clipping point. Secondly, S&V measures in THD+N instead of THD and most companies don't measure the THD+N.

S&V say clipping is at 0.3%THD+N. Now I have the 49tx and Pioneer rates this receiver with 0.09%THD. Now S&V's number is 3 times higher than Pioneer's, so the 49tx is defintely going put out more than it's published rating when it's allowed three times as much harmonic distortion in the signal. Therefore, maybe a company like Kenwood for example defines clipping as say 0.5%THD and that's why they don't meet the published power rating.

Note that S&V measures THD+N (total harmonic distortion plus noise) not THD, so I believe receivers would have a higher THD+N than a THD level. I don't know what Pioneer's THD+N level is and I don't think most manufacturers post this so that kindof makes this comparision unfair.

Daniel Smith

P.S. For your info I got S&V numbers from their January 2002 on page 94 in their "Behind The Numbers" article.

 

[Charles M Berry]

Thank you to everyone who checked out my graph, I worked hard on it and wanted to share it with all of you, as I have learned so much by lurking here at the HTF.

There's two points that makes this comparasion unbalanced.

Very valid critiques Daniel. While my chart may be
"unbalanced", I still don't think that my comparison is "unfair", for this reason: It is certainly true that some manufacturer's use a different definition of what constitutes clipping, and this may mean that Brand X reciever got unfairly judged by my chart, but we need to ask why Brand X decides to increase the acceptable amount of distortion (as you suggest Kenwood might do).

The reason, as Nick C. points out, is to increase sales. Again, increased sales is a 100% legitimate reason to doing this, but that does not mean it is 100% honest.

So, even though Kenwood seems to get picked on by my chart because Kenwood supposedly uses a degraded definition of clipping, this does not change the CONCLUSION that can be drawn from my chart. The power claims are still exagerated in the sense that, whether or not a company is flat out inflating wpc, or using a different def. of clipping, they are NOT living up to the wpc under the generally accepted definitions of what distortion is.

I still stand by my chart as an approximation of how HONEST brand X is. Maybe what the industry needs to do is agree on a fixed amount of acceptable distortion, and very clearly designated number of channels driven at once.

Again, I spent my time making this chart because I wanted to give back a little to HTF. Thanks you for all who checked it out.

 

[Frank Frandsen]

Interesting information. Thanks. After several receivers I've figured out the secret to getting advertised power.....A separate out board amp.

Frank