Watts, RMS, PMPO etc.

teraside said:
Uhm... :o hehehe :D ;) :p

Which speakers do you have?
Click to expand...

Cambridge Soundworks 2.1 and my Panasonic Hifi. @ my TV I have a Philips Home theatre. For private listening I have Shure SE210 in-ears.

Nothing fancy, but good enough that I don't notice that it's not very fancy :D
 
sn3rd said:
Cambridge Soundworks 2.1 and my Panasonic Hifi. @ my TV I have a Philips Home theatre. For private listening I have Shure SE210 in-ears.

Nothing fancy, but good enough that I don't notice that it's not very fancy :D
Click to expand...

For sake of me being completely dead tired (for the 2nd day in a row). How much did you spend on that 2.1 set?

I'm not an earphone kind of guy, frustrates me :p
 
teraside said:
For sake of me being completely dead tired (for the 2nd day in a row). How much did you spend on that 2.1 set?
Click to expand...

I can't remember exactly. A few hundred over 10 years ago :D
(and still going strong)

teraside said:
I'm not an earphone kind of guy, frustrates me :p
Click to expand...

When you hear these, you'll know audio bliss. No one thinks they're worth the price until you actually HEAR what the sound is like
 
Hi,

I want to buy a 5.1 home cinema loudspeaker system. :D
But I also have problems with the watt data.

http://www.teufel.de/de/THXsysteme/Theater-8-THX-Ultra-2.cfm?show=technik

The subwoofer has 700 Watt "sinus" and 1200 Watt "Musikleistung" (= audio power = P.M.P.O ???)

Well... 1200 Watt PMPO is not very much....

The satellites have 160 Watt "long-term" and 240 Watt "short-term". (IEC-Norm???)
Whats that? RMS? Sinus? PMPO?
 
There is no standard in the measuring.Not all RMS ratings are the same because they are differently measured,so a good quality 100w rms speaker can kick a lower quality 150w rms speaker's @ss.

You can't just convert PMPO to RMS,PMPO uses the highest peak rating of a speaker in perfect conditions.

Also watch out for RMS Peak.
 
My lecturer back in the day when I was studying engineering told me that, it's all fine and dandy posting a PMPO measurement, which, for all intents and purposes is a value obtained about 100mS before the amplifier blows up and at about 25% distortion. In other words, utter BS. And I promise you, salesmen at HIFI CORPORATION will get angry with you if you try and set them straight.
 
RMS peak is not really the active value that does the work. It is the same as saying the peak voltage coming out the plug is 325 volts AC

RMS Peak = RMS x 1.414 roughly
 
Turiko said:
RMS peak is not really the active value that does the work. It is the same as saying the peak voltage coming out the plug is 325 volts AC

RMS Peak = RMS x 1.414 roughly
Click to expand...

Only if assuming a sinusoidal signal...
 
They managed to confuse me again today sn3rd :p I'm saying a mantra > RMS should be high value, should be high, should be high :p ;) :D
 
RMS peak?? How does RMS peak??

Code: 
Vrms = SQRT[ 1/T Integral(over one period)[ Vp^2 dt] ]
 
teraside said:
They managed to confuse me again today sn3rd :p I'm saying a mantra > RMS should be high value, should be high, should be high :p ;) :D
Click to expand...

It should be high. But as I mentioned before (and as they are currently saying), you have to look at the level of distortion that the value is determined for.

Saying that the speakers can handle 100W RMS @ 25% distortion means that to be able to hear clear sound, you may only be able to put 50 - 60W on them.

RMS SHOULD be a high value, but distortion should be a low value.

Edit: Oh, and remember that efficiency is an important parameter. There ain't no such animal as perfect efficiency. Impedance plays an important role here (impedance matching to (hopefully) get power factor as close to 1 as possible). Imagine having 100W speakers where you lose 50W to heat??
 
Last edited:
You must log in or register to reply here.
Back
Top
Sign up to the MyBroadband newsletter
X