What are those wattage numbers?

[admin_exported]

I am looking at a number of home theater systems. They are feature rich (eg DLNA, connects to Internet directly etc) and are pretty low cost. One thing that puzzles me is the power numbers.

For example, the Sony BDV-E190 manual says POWER OUTPUT (rated) to the various speakers are 40W L, 40W R, 40W C, 40W LS, 40W RS, 70W C and 70W SW. But the total power consumption is only 95W! :help:

What exactly do those speaker numbers mean?

Thanks.

 

[toyota man]

Hi the 95w is the power consumed by the unit while running a bit like a 100w light bulb the output to the speakers is max watts delivered to each speaker I am sure some one will put it better than that there are some very clever soles on this forum

 

[RobinKidderminster]

Not sure where yr numbers come from but ignore them. If there is one thing about a one box solution which is good then its that all components work ok together. The downside ofcourse is forget any upgrade except bin&buy again. These systems can sound ok but dont expect too much. Listen carefully in store. Take a look too at second hand. Plenty of advice here. Watts? Whatts the proble?

 

[Anonymous]

Thanks. The numbers are right off the Sony document in the link. It's similar with Samsung and others.

They have to mean something right? Is there a new mathematics in place since the last time I bought a Dolby Surround home theater system 20 years ago?

 

[toyota man]

Hi as I said the 95w is how much power the unit uses when switched on in normal use the other figures are the watts available to drive each speaker the more watts the better from your post I susspect that you have 40w per channel and 70w for the subwoofer which is enough if you dont have a massive listening rooom

 

[MajorFubar]

I think what he's saying is, how can it deliver that kind of wattage to the speakers when its total power consumption is only 95W to start with.

 

[toyota man]

the power consumtion is at 240volts as the voltage drops so the current increases so it will deliver a higher wattage at a lower votage

 

[Anonymous]

toyota man, thanks for trying to be helpful. I am a part-time electrical engineer.

 

[RobinKidderminster]

specs say 300w. The 75w is ON as apposed to 0.3w standby. As I said ignore them. Even they are into 3ohm. Go listen. Turn it up. Whats room size? What is yr expectation. As a part time elect engineer I would think u can sort the 'real'/important figures from the 'hype'.

Cheers

 

[Anonymous]

I think I found the answer. The speaker numbers are just ficitious marketing gobbledygook (peak music power). See http://en.wikipedia.org/wiki/Audio_power#PMPO. So that Sony set is about 10W per channel.

FTC clearly mandates RMS power. So I guess in the US (I am not in the US) you wouldn't be seeing such numbers in the stores.