What would I possibly hear different at 120 watts vs 200 watts?

[Mr. Widget]

I already own the OutLaw so no intention of not using it, BUT . . . am I correct in the simple interpretation of the bench test linked below.

Sony STR-ZA5000 ES A/V Receiver Review Test Bench

Test Bench Two channels driven continuously into 8-ohm loads: 0.1% distortion at 139.3 watts 1% distortion at 175.3 watts Five channels driven continuously into 8-ohm loads: 0.1% distortion at 103.6 watts 1% distortion at 135.1 watts Seven channels driven continuously into 8-ohm loads: 0.1%...

www.soundandvision.com

The Sony STR AZ5000ES can hit 100 watts per channel on 7 channels simultaneously?

Assuming for a moment that's true am I further correct in this scenario (using the SPL website).

Let's say one is listening to a movie at 85 dB 3.5 meters back; the channel draw would look like this:

towers 90 dB sensitivity = 2 watts x 2 = 4w
center 87 dB sensitivity = 4 watts x 1 = 4w
bookshelf 86 dB sensitivity = 5 watts x 2 = 10w

total = 18 watts!

So under normal listening levels the amp is barely using power. Then comes a loud noise pushing to 100 dB

towers 90 dB sensitivity = 62 watts x 2 = 124w
center 87 dB sensitivity = 120 watts x 1 = 120w
bookshelf 86 dB sensitivity = 120 watts x 2 = 240w

total = 484 watts

The amp is still no where near 7 channels at 100w or what I assume was 700 watts plus during the bench test, and this is just momentary. Kinda looks like an amp is 100% unnecessary if all that is correct.

It is true that most of the time we only use a few watts with most systems, but to avoid clipping your amp, having extra headroom's needed. I like to have 10dB of headroom, but 6dB maybe OK.

That said, if you occasionally turn up the system to higher SPL peaks you will need another 10dB or so of headroom. So you would need a minimum of 100wpc.

 

[RayDunzl]

I see a 20dB difference between average and peak generally.

Example:

Leq : equivalent continuous sound level is the sound level in decibels, having the same total sound energy as the fluctuating level measured. Leq is also known as the time-average sound level (LAT).

So, range of about a watt to 100 watts here during loudish sessions.

Just a little louder will bump it right up, though.

 

[Old_School_Brad]

I see a 20dB difference between average and peak generally.

Example:

Leq : equivalent continuous sound level is the sound level in decibels, having the same total sound energy as the fluctuating level measured. Leq is also known as the time-average sound level (LAT).

View attachment 440820

So, range of about a watt to 100 watts here during loudish sessions.

Just a little louder will bump it right up, though.

For these examples to provide meaningful insights, the track and music genre should be included, along with information on whether the measured system was capable of full-range playback.

This is crucial because weighting (Z or C) and recorded values are highly sensitive to low frequencies. If a system rolls off at 50 Hz, the C or Z weighting will register lower values, making the perceived difference between dBA average and bass transients smaller. In contrast, the same track played at the same dBA average on a system with strong output below 50 Hz would show a greater difference.

Of course, this becomes less relevant if the music in question lacks significant bass content.

It would be interesting to compare the same tracks at the same(ish) dBA avg. value across different systems to see the difference.