In the review for the Marantz 5003, at 5 channels @ 1% it is 131% of rated power (118/90). Wow, so you get even more watts than specified!

Same for the older 8002, at 5 channels @ 1% it is 107% of rated power (133.8/125).

This post has been edited by jchong: Jun 28 2009, 11:40 PM

but 1% distortion lo ...

The reviews give the 1% measurement since that's about when clipping occurs. And generally people wanna know when it clips because that's seen to be the limit of amp power.

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Added on June 28, 2009, 11:50 pmDunno, but they do seem to fall quickly under load. Even the RX-V863 also same thing, at 5 channels @ 1% it is 46% of rated power (48.4/105).

This post has been edited by jchong: Jun 28 2009, 11:50 PM

ya ... i remembered last time taukeh mpyw (ex-863 owner) posted tat

pretty scary

how to check the power when using?
sorry for the noob question

The next sld be power amp liao. No point still at avr stage. Must try multi-channels power amp. Upgrade a step higher

You have to read reviews which measure the power output. Like this one: http://www.soundandvisionmag.com/receivers...mics-page2.html

Here's the RX-V1800's performance (From Sound & Vision)

Yamaha's RX-V1800 yielded the fine technical performance usual from the firm's A/V receivers. Power exceeded its specs by a good margin and bettered 100 watts all around, even with 5 channels driven. The unit's power supply appeared to run out of current when 2 more channels were added, however, since the 7-channel result dropped by nearly 3 dB, to 55 watts—a non-issue in the real world., where program signals never demand this level of stability. Yamaha equips its receiver with a software setup switch for speakers of 6-ohms or lower, which effectively limits power to about two thirds.

Frequency response, distortion, and D/A linearity were uniformly excellent, and crossover responses were all bang on the numbers, with nicely accurate slopes—not always the case. PCM and Dolby Digital noise were very good, if a dB or 2 shy of the best we've seen, although S/N on the analog-multichannel inputs was truly superior. I note that the analog input was a good bit more sensitive than the digital ones (re: our reference levels of -20 dBFS or 200 mV for 1 watt output), so listeners who switch from the latter to the former without adjusting the volume could be in for a roughly 10 dB surprise. While this sounds like a lot, most characterize it as only about subjectively "twice as loud" or so.

DOLBY DIGITAL PERFORMANCE
All data were obtained from various test DVDs using 16-bit dithered test signals, which set limits on measured distorting and noise performance. Reference input level is –20 dBFS, and reference output is 1 watt into 8 ohms. Volume setting for reference level was -6. All level trims at zero, except for subwoofer-related tests, all speakers were set to "large," subwoofer on. All are worst-case figures where applicable.

Output at clipping (1 kHz into 8/4 ohms)
1 channel driven: 158/281 W (22/24.5 dBW)*
5 channels driven (8 ohms): 103 W (20.1 dBW)
7 channels driven (8 ohms): 55 W (17.4 dBW)
Distortion at 1 watt (THD+N, 1 kHz)
8/4 ohms: 0.02/0.03%
Noise level (A-wtd): –73.4 dB
Excess noise (with sine tone)
16-bit (EN16): 0.9 dB
Frequency response: 20 Hz to 20 kHz +0, –0.2 dB

http://www.soundandvisionmag.com/receivers...v-receiver.html

At 5 channels driven, it is better than 3900. Strange.......

Wah Sooooo technical.
Anyway which is better?

Yeah, at least the RXV-1800 is closer to the rated power. At 5 channels it is 79.2% of rated power (103/130).

But still, I wonder why Yammy's power is quite below the rating. Looking at the tests for Denon, Marantz and Onkyo they are usually close to the rated power (or even higher!).

This post has been edited by jchong: Jun 29 2009, 11:41 AM

same with mee.... to technical
me layman only

was using the RXV2200 partnered with infinity renaissance 80, (main) B&W (center) revolver (rear) Aegis ( back center) M&K90(sub)

i feel that the sound was very good( very muscular ) compared to denon 3802 ( very lean and soft ) and made the purchase in A&L bbplaza, but the pioneer AX4 was simply stunning, superb then, (no budget around 5k+, think the cpu processor was 48bit (no one seems to have Yamaha for demo in Ipoh...until now also none )..... but when i heared pioneer 815, 816(soree, think that's the model) in my frens shop, notice that my main center and rear doesn't seem to perform within expectation to the pioneer, well maybe pioneer is designed to produce higher frequencies... or more noisier

only recently bought sony 870 HITB, sold off part of my AV setup, use the HITB 2months only,
( well i would say HITB's really improve a lot, sound is very well surrounded.......but still missing something)

now back with 3900..5.1 setup.... MA BR2 (main) Aegis & M&K sub(center luckily not sold yet) hmm.....rear now using paria Qualye ...haha...haha...

well maybe its the matching or sensitivity, and now i can hear the missing sonics, a lot of tingy clinky sounds but not harsh and at times still have some sibilance... maybe not run-in yet.

and soree to say the 3900 performs very well in my living hall, more enveloping and balanced as compared to sound rooms demo i've been.

the calibration is only auto on the YPAO, there is so much of difference, well maybe newer sets are getting better sonically...( oh soree yamaha is YPAO, others use Audyssey)

i recently been having problem with my yamaha rx-v663. Its been shutting off on me when i have the volume high, around -30db. When i turn it back on, it says check speaker wires so i redid all the speaker wires and it still happens. Im using a 5.1 system with Epos m12.2 front speakers and Epos M8 centre speaker. I was wondering if its because of too much power usage of something like that. I have also check the impendence which is set at 8 Ohm and the receiver gets hot to the touch after it shuts down. If some one has a similar problem or any suggestion, please help.

very good layman test

try isolating, one speakeer at a time to test the culprit, very pratical fault finding

Don't know about others...but -30db is not loud for my case..usually my listening volume is -10db to -15db for movies and -25db for music.

I think ur amp not enough power to drive ur speakers la..

Wow that's loud dude. My max for movies only -20db n music -40db only. You must have a big room.

Well...my seating distance is about 15 feet..i have small room only la..

mine only in range -25db to -40db....
i guess my room even smaller...

try once put -20db..too loud...make me feel headache..

15' seating distance means your room is quite big.

maybe piscesguy is using low sensitivity speakers, thats y can go to-10..... hmm....

Only recently? That means all this while with current spkr setup, you have no issue at all. The avr shut down might be due to overheating. This is to safeguard the amp from further damage.