AVS Forum banner
  • Our native mobile app has a new name: Fora Communities. Learn more.

power output vs THD

664 Views 8 Replies 3 Participants Last post by  m. zillch
I am confused by this power output ratings from SR7013 9.2 Channel 4K Ultra HD AV Receiver with IMAX Enhanced, Dolby Atmos, Auro-3D, HEOS, AirPlay 2 and Alexa Voice Compatibility AV Receivers | Marantz :

Power Output (8 ohm, 20 Hz - 20 kHz, 0.08% 2ch Drive)110 W
Power Output (8 ohm, 20 Hz - 20 kHz, 0.05% 2ch Drive)125 W

I thought all things else equal, the power output would be higher for a higher THD 0.08%. Anyone can enlighten me why my understanding does not square with the above ratings?
1 - 9 of 9 Posts
I am confused by this power output ratings from SR7013 9.2 Channel 4K Ultra HD AV Receiver with IMAX Enhanced, Dolby Atmos, Auro-3D, HEOS, AirPlay 2 and Alexa Voice Compatibility AV Receivers | Marantz :

Power Output (8 ohm, 20 Hz - 20 kHz, 0.08% 2ch Drive)110 W
Power Output (8 ohm, 20 Hz - 20 kHz, 0.05% 2ch Drive)125 W

I thought all things else equal, the power output would be higher for a higher THD 0.08%. Anyone can enlighten me why my understanding does not square with the above ratings?
No according to your data, you got it right. It could be a misprint.
Specifications

Number of Poweramps9
Power Output (8 ohm, 20 Hz - 20 kHz, 0.08% 2ch Drive)110 W
Power Output (8 ohm, 20 Hz - 20 kHz, 0.05% 2ch Drive)125 W
Power Output (6 ohm, 1 kHz, 0.7% 2ch Drive)165 W
Power Output (6 ohm, 1 kHz, 10% 1ch Drive)235 W

I suspect the correction to the misprint is:

Specifications

Number of Poweramps9
Power Output (8 ohm, 20 Hz - 20 kHz, 0.08% 2ch Drive)110 W
Power Output (8 ohm, 20 Hz - 20 kHz, 0.05% 1ch Drive)125 W
Power Output (6 ohm, 1 kHz, 0.7% 2ch Drive)165 W
Power Output (6 ohm, 1 kHz, 10% 1ch Drive)235 W

Typically these multi channel amps get stronger output and lesser distortion the fewer channels are driven.
See less See more
  • Like
Reactions: 1
It really doesn't matter because you will never head any distortion 1% or less with your ears.
No according to your data, you got it right. It could be a misprint.
I found this quote of the above stats from this page Can Sound United Bring Honest Power Ratings to AV Receivers?

I'd expect the author who is an expert to notice that error if it is a misprint.
It really doesn't matter because you will never head any distortion 1% or less with your ears.
True. I just wanted to check if my view is upside down.
The graph https://www.audioholics.com/audio-a...wer-ratings/AVRX3300Wpower.jpg/image_preview2 does indicate the THD decrease while the power (W) increase BEFORE the knee point; and then increase after the knee point. This is power sweep at a constant 1khz though, not sure if that pattern holds for the above 20 Hz - 20 kHz case.
Generally speaking using a 1kHz only spec is "best case scenario". 20-20kHz is markedly more difficult. I'll be back with evidence in a moment.
Here. Notice the maximum output at 1kHz is higher than at 20Hz. Enlarge the image there called "Figures 4 & 5. Denon AVR-4310CI Continuous Power vs Frequency (8 ohms left, 4 ohms, right) "
The frequency extremes are the hardest parts for an amp to reproduce before clipping.
---
On a side note, not directed at you but rather the general audience.

People get overally obsessed with power specs, even Gene. The most important thing to understand is that doubling your power means (assuming your speakers are rated to take it) you can play music/movies 3dB more loudly. That's louder but not a ton. So worrying about if it is worth upgrading one amp having, say, 100 watts/ch to another one that's 128watts/ch is a measly and hardly worth even thinking about increase of 1dB.

Go change the volume knob on your existing receiver down 1dB and then back up again, while playing music, and tell me if that difference is worth spending hundreds of dollars on. It isn't.

People love numbers so the marketers exploit this and instill "watt fever". If they really wanted to help us they'd provide power level meteres like they often did in the 70/80s, but they realized that feature enlightens consumers as to how much power they really use and there is more money to be made keeping consumers in the dark and instead pushing power FUD: fear, uncertainty, and doubt.

"Oh no. Do I have enough watts and how will I know when I'm in danger of clipping?!"


Do a search on this theme and you'll see tons of threads.
See less See more
  • Like
Reactions: 1
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top