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#1
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panasonic 'home theatre' specs - crap?!
Hi,
I was just looking at some of the Panasonic home theather specs to see in terms of the amp power and speakers themsevles. The THD is 10%!!!! Isnt that pretty crap ?????? I know of amps with 1% (admittedly hi-fi amps, not home theatre) - but wouldnt they have WAY better sound quality output than the panasonic h.t. ones ? Next question...speakers. The frequency range spec quotes that for the range it is, 75Hz-50kHz, it is -16 dB! Isnt that very very poor too ???? I have read that +/- 3dB is considered good, so -16 must be attrocious ? Last thing, for speakers in general - what is an average sound pressure level ???? The pana's one is 84dB ..... is this average? Would 90dB be considered good?? Thanks,, Andrew |
#2
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panasonic 'home theatre' specs - crap?!
"andrew_h" wrote ...
I was just looking at some of the Panasonic home theather specs to see in terms of the amp power and speakers themsevles. The THD is 10%!!!! Isnt that pretty crap ?????? I know of amps with 1% (admittedly hi-fi amps, not home theatre) - but wouldnt they have WAY better sound quality output than the panasonic h.t. ones ? Next question...speakers. The frequency range spec quotes that for the range it is, 75Hz-50kHz, it is -16 dB! Isnt that very very poor too ???? I have read that +/- 3dB is considered good, so -16 must be attrocious ? Rule of thumb about published "specs": You can safely assume that the actual performance is even worst than the numbers indicate. What is a "Panasonic home theatre"? Some kind of amp with a bunch of channels in the same cardboard box with a bunch of cheap speakers? Yuck. I wouldn't recommend buying by the numbers. Chances are I wouldn't recommend some plastic home-theatre kit (just add water?) with or without the numbers. |
#3
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panasonic 'home theatre' specs - crap?!
Sorry, this page:
http://panasonic.com.au/products/cat...fm?objectID=66 - I was looking at those models? It is not cheap though ($1200)... so thats why I was looking at the specs though, to see how it compared to others... |
#4
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panasonic 'home theatre' specs - crap?!
"andrew_h" wrote in message ups.com... Sorry, this page: http://panasonic.com.au/products/cat...fm?objectID=66 - I was looking at those models? It is not cheap though ($1200)... so thats why I was looking at the specs though, to see how it compared to others... Certainly at this price level you can go with separates. DVD players die like flies compared to your other components. At least get a system with a separate DVD player. Pioneer DVD players have been the most reliable on average the past several years. I recommend receivers by Yamaha, Denon, Onkyo, or Sony, having had experience on many types of home theater receivers. Mark Z. |
#5
Posted to rec.audio.tech
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panasonic 'home theatre' specs - crap?!
"andrew_h" wrote in message ups.com... Hi, I was just looking at some of the Panasonic home theather specs to see in terms of the amp power and speakers themsevles. The THD is 10%!!!! Isnt that pretty crap ?????? I know of amps with 1% (admittedly hi-fi amps, not home theatre) - but wouldnt they have WAY better sound quality output than the panasonic h.t. ones ? Next question...speakers. The frequency range spec quotes that for the range it is, 75Hz-50kHz, it is -16 dB! Isnt that very very poor too ???? I have read that +/- 3dB is considered good, so -16 must be attrocious ? Last thing, for speakers in general - what is an average sound pressure level ???? The pana's one is 84dB ..... is this average? Would 90dB be considered good?? Thanks,, Andrew 10% with modern amps? Think about it, it doesn't make sense. Escpecially knowing Panasonic which is a reasonalbly serious company, not an obscure company that doens't have to care about its reputation. Unless it is sold for a few dollards, no modern amp produce such high level distorsion except when output start clipping beyond maximum rated power. Dan |
#6
Posted to rec.audio.tech
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panasonic 'home theatre' specs - crap?!
"andrew_h" wrote in message
ups.com Hi, I was just looking at some of the Panasonic home theather specs to see in terms of the amp power and speakers themsevles. The THD is 10%!!!! Isnt that pretty crap ?????? This is mostly a way to inflate the power rating of the power amp. It's also a matter of conforming to how specs for certain classes of audio gear are specified. IOW, the same power amp might put out 30 watts at 0.1% THD, 35 watts at 1% THD and 45 watts at 10% THD. It is traditional to rate mid-fi hi fi gear for power at 1% or 0.1% THD. It is traditional to rate portable or low cost hi fi gear at 10% THD. Next question...speakers. The frequency range spec quotes that for the range it is, 75Hz-50kHz, it is -16 dB! Isnt that very very poor too ???? I have read that +/- 3dB is considered good, so -16 must be attrocious ? This more of the same philosophy I was talking about with the power amp. First off loudspeaker frequency response specs are to be taken with a grain of salt, sometimes a whole 5 pound bag! Secondly the same speaker might be 150-10KHz +/- 3 dB, 100-15 KHz +/- 10 dB or 75=50 KHz +/- 16 dB. The 150-10 KHz spec might look kinda dire, but a speaker that sounds pretty good, admittedly a bit light on bass could fit into this spec. Last thing, for speakers in general - what is an average sound pressure level ???? The pana's one is 84dB ..... is this average? Would 90dB be considered good?? Usually speaker efficiency is given in terms of dB per watt, measured 1 meter away from the acoustical or geometric center of the speaker. Things get vague fast because speaker efficiency varies strongly based on other parameters that typically go unstated. However, 90 dB/watt under *standard* conditions (whose standard???) is considered to be on the high side of average efficiency. It turns out that low efficiency can be a good thing because it might indicate that the speaker has better-than-average bass response given its size. All things considered, you might just want to buy the thing with an iron-clad money back guarantee, and see how it works out for you in your situation. |
#7
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panasonic 'home theatre' specs - crap?!
Very nicely explained. Though this wasn't my query, but did answered lots of
'might be' queries. wrote in message ups.com... Richard Crowley wrote: "andrew_h" wrote ... I was just looking at some of the Panasonic home theather specs to see in terms of the amp power and speakers themsevles. Rule of thumb about published "specs": You can safely assume that the actual performance is even worst than the numbers indicate. Actually, the opposite is generally true. Publishing specifications actually has real legal implications: if the unit can be shown NOT to meet the specifications, many jurisdictions provide for economic and or legal recourse on the part of the purchaser, usually including but not limited to full refund of the purshase price. Some jurisdictions allow for further penalties. It is thus very much in the manufacturer's self-interest to publish specifications which actual units sold to the end user stand a pretty high chance of meeting with a reasonably adequate margin. In looking at the specification, the 10% THD is most likely chosen to get as high a number as possible for the power output. For example: Audio Power Output (front x2) Watts RMS 170 Front Reference Spec (1 kHz, 6 ohms 10%THD) Does that mean the amplifier is ALWAYS producing 10%? Nope, it is probable that to arrive at the 170 watts spec, they had to drive the amplifier sufficiently into clipping to reach the 170 watt level. In reality, it might well be below 0.1% at 150 watts and lower. That being said, these days it is AWFULLY difficult to build amplifiers that have 10% distortion over most of their power range. Even using the cheapest possible components, i.e., mass-produced monolythic power amplifier modules, with minimal external parts count, 0.1% is EASY to achieve at levels below clipping. So, what I suspect we see here is an attempt to platy one- upsmanship on the power spec by loosening the limits on THD, and that allows them to get 5-10% higher power rating. Is it wrong, evil, dishonest? Absolutely not: they are completely upfront and all the information is there IF you know how to interpret the numbers. But that's the key. Is it overpriced junk? Well, one man's junk is another's ... To those that are saying you can do better with separates, you're ignoring the fact that it's a wireless system: to some people, that particular function may be worth the price of admission. Given that, consider how much it would cost to get the same level of functionality, i.e. wireless speaker connections, with seperates. I'd bet you couldn't get close. Add to that a significant feature of such systems, which the wireless part speaks to, is the convenience in setup and operation. To many, that's worth paying for, and it's not anywhare as easy to obtain that ease of intergration and deployment with cherry-picked separates. You either wind up with a traffic jam of remotes on your coffee table or a single "univeral" remote that has the easy user interface of an ENIAC-I. |
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