Amplifier power requirements vs type of music, peak/dynamic power vs sustained power...

[bigguyca]

@Xulonn

Back in the day I owned the ADS L810 series 2 powered by a Carver M1…now I have a pair of Salk Veracity STs powered by a 2Cherry….and yes, you are going to love the craftsmanship of the woodworking performed by Jim Salk's team! The sound ain’t bad either. The transmission line will give you a deep, tuneful low end that is easy to integrate with a sealed subwoofer if you ever decide it is needed.

The Salks are 6 ohm nominal, 4 ohm minimum….so you should probably consider their sensitivity as being closer to 86 db as I’m pretty sure the 88 db is based on 2.83 volts @ 1M which would be about 1.5 watts.

As for power and headroom: If you plug your data into this website calculator, you will see that with 2 loudspeakers placed within 4 feet of the rear walls and powered by 8 watts, the SPL at the listening position is 91 db…and with a 70 watt amplifier you are close to the 10x headroom for peaks.

(dB)

OK, 91dB SPL is the total level of two equal, uncorrelated 88dB SPL sources using the assumptions in your post. What is the significance of 91dB SPL? Is it just an arbitrary value?

 

[snapsc]

The only significance is that 91 average listening level is pretty loud... and only required 8 watts leaving plenty of amplifier headroom for peaks.

Therefore, it would seem that the Classe amplifier with 70 watts should be sufficient....and of course... this is all on paper. In an actual room, depending on many factors, the volume could be more and it could be less.

 

[CDMC]

The only significance is that 91 average listening level is pretty loud... and only required 8 watts leaving plenty of amplifier headroom for peaks.

Therefore, it would seem that the Classe amplifier with 70 watts should be sufficient....and of course... this is all on paper. In an actual room, depending on many factors, the volume could be more and it could be less.

I call 91db really loud for average. I started using the Bob Katz 81 db (84 db for stereo) at -20db pink noise and find it plenty loud for music. On compressed stuff sometimes too loud.

 

[Blumlein 88]

I call 91db really loud for average. I started using the Bob Katz 81 db (84 db for stereo) at -20db pink noise and find it plenty loud for music. On compressed stuff sometimes too loud.

Yes, I've taken to setting up my systems on the Bob Katz idea. Works wonderfully. Maybe there is a better way, but this one is very good. You don't over-power things, and you leave very little on the table.

Here is an explanation. It is rather over explained, but if you bother to read it then it makes better sense.
https://www.digido.com/portfolio-item/level-practices-part-2/

 

[CDMC]

Yes, I've taken to setting up my systems on the Bob Katz idea. Works wonderfully. Maybe there is a better way, but this one is very good. You don't over-power things, and you leave very little on the table.

Here is an explanation. It is rather over explained, but if you bother to read it then it makes better sense.
https://www.digido.com/portfolio-item/level-practices-part-2/

https://www.soundonsound.com/techniques/establishing-project-studio-reference-monitoring-levels

First a correction, I went back and looked and I am using 81db for the speaker pair (78 db single) for my reference in my living room and 77db for the pair in my office. From the article linked above, you will see why the correction is applied.

I recommend reading the Sound on Sound article which goes through step by step how to calibrate. Important is to adjust the level based on room size (chart is on page 3). Keep in mind that the reference is for 1 speaker, so if measuring the pair your volume will be 3db higher. The room size is important because the 83 db reference in a huge room becomes way to loud in a normal sized room. After finding the reference I then use a trimmed post-it to mark this point on my volume knob so I know the reference level. This is your K20 point and the reference calibration level is you have volume normalization enabled in Jriver.

I also have a second reference point of -16db (LUFS) (which is lower on the volume knob than the -20 db), which is a compromise for streaming service normalization. I set Roon to target -16LUFS with a -8db for unknown sources, which gives a good compromise between streaming and my local library.

I have found that with using these reference levels for cranked up listening, I get full balanced sound on most music (since these are the levels that good studio practitioners are mixing at), without fatigue. That said, in my office on my desktop system, which plays all day, I only turn up to the reference level when cranking something up. My day to day listening level is 15-20 db lower (mid 50 db range average).

 

[oursmagenta]

Hello,

Regarding the transient needed power VS music genre. I have two tracks on an album that may exhibit an interesting behavior.
Track 1
Track 2

On my l30 + e30 + hd600 there is no sign of distortion on sustained note from one of the singers.

However on my sr6014 (rated around 185w) with some triangles comètes 902 (2 ways bookshelf rated at 80w max input power and 94db sensitivity), I clearly hear a lot of distortion.

I thought first that it maybe due to the speaker, but the note is not that loud with respect to other music/genre that I put through them.

I was like wow, an almost a capella singer going through a 18th century sacred music partition can show the limits of my system?

So could it be a an amp power shortage?
Or the speakers could exhibit such behavior (sustained loud notes giving more distortion than more transient ones, maybe due to some form of bad resonance)?