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Which amplification is more suitable?

That looks more like the 4.04 with a woofer in the bottom not subwoofer. They call it a 3 way which it might be but one of the woofers , I think the bottom rolls off and doesn't play above 80hz where the front runs full more like a 2.5 way. I think the 5.04 has the spikes not the black base. Anyway they shouldn't need a lot of power. WiiM amp, or Fosi V3, Topping , entry line from Audiophonics since you're in the EU. I have no idea on reliability, service etc.. on any of these amps just do your research.

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Immagine 2024-08-11 160757.png

this is the little r 40m
 
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I always attack these issue from the recommendation once given by French speaker manufacturer Cabasse in a very well written leaflet from the '70s.

Considering that a baby grand piano can produce around 115 dB peak SPL at 1 m meter (for brief milliseconds) when playing fortissimo, Cabasse advocated to compute the power of amplifiers in order to achieve this sound pressure level, which is realistic at home. For that, it is necessary to take into account the sensitivity specification of the speaker (hoping it is accurate and fairly measured...), the peak power output corresponding to the mean power specification of the amplifier (for sinus signal, peak power is double that of mean power) and a 3 dB gain due to the use of two speakers in stereo, speakers whose combined outputs will roughly add up to 3 dB in a room.

Application in musica's case :

Gain (in dB power) required to obtain 115 dB : 115 (aim) less 3 dB (gain of use of 2 speakers in stereo) less 91 dB (sensitivity of the actual speaker used), that give 21 dB of gain (115-3-21).

If 1 W set 0 dB, 21 dB will be around 130 W (10 log 130 = about 21).

Since we speak of a peak power requirement, that means that the power of the amplifier, which is specified with sinus signal, is half 130 W, that is 65 W.

For the reproduction in high fidelity of a realistic home instrument (a baby grand piano) at home with speakers of 91 dB/1W/1m sensitivity, the amplification power required is thus 65 W per channel.

Or course, the faithful reproduction of more robust instruments (church organ, percussion, orchestra) or music (electronic music with deep bass) would required more power to be listen to undistorted (if well recorded and produced).

Hence, 65 W per channels is a bare minimum, not a limit!

This way of thinking excludes some caveats (behaviour of specific amplifier, speaker power handling, crest factor of different musical genres, listening habit...) that are thoroughly addressed in the above mentioned leaflet, but I think that, in this day and age, when power is cheap and speakers have became more robust, it would add unnecessary complexity just to give a simple advise.
What percentage of listeners regularly listen to music with 115 dB peaks or 109 dB peaks at their listening distance? Sitting near an open baby grand, while someone bangs the keys as hard as they can is not going to be for everybody.

When I asked the question here, most people were listening at 70-80db for their average level from their listening distance. https://www.audiosciencereview.com/...-and-db-level-at-that-distance-at-home.51453/
 
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As written in the Cabasse leaflet I refer to above, when measuring SPL at 1 m distance produced by a baby grand piano when someone performs Beethoven's Appassionata sonata, the peaks reach 115 dB for brief milliseconds at the moment of the attacks when the pianist plays fff nuances, but the mean SPL at such nuances is about 109 dB. On the other hand, when the pianist plays pp nuances, the mean SPL is only about 60 dB. Cabasse measured a mean SPL of about 75 dB for the performance of the entire sonata.
Bear in mind this values were taken 1 m from the piano. At a good listening position, usually several meters away from a piano at a concert, the levels would obviously have been lower.

This example shows the huge dynamic range acoustic instruments produced in real life. In order to listen to in high fidelity recordings made in that spirit, power is indispensable not to listen to loud, but to listen to comfortably at natural levels without having the amplifier generating distortion, particularly on the peaks (attacks of the notes).

Yes it can be considered a worst case situation for not everybody is listening to high fidelity recordings of natural music. But that is not to say electronic or pop music doesn't have their own power requirements, especially at deep bass nowadays, and, as pointed out by Sokel, power amplifier headroom is a mandatory requirement when equalising.

In the thread you referred to, you rightly wrote in your OP that a cell phone app cannot register the true peak SPL. As explained by Amirm in this video from about 20'02'', measuring true peak level requires specialised equipment not available for the commoners. Cabasse used to published oscillographs of soundwaves captured by measurement microphones to exemplifies the peaks.
 
I suspect all recordings as produced for consumption, limit the peaks somewhat...
Some maybe do.
Classical don't.

(that's 2.8 meters away)

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More here:


(always note the weighting,differences are vast)
 
Some maybe do.
Classical don't.

(that's 2.8 meters away)

View attachment 386059

More here:


(always note the weighting,differences are vast)
Hmm - Are you sure that mics or desks don't have some limiting built in (genuine question, I'm not baiting)? In the past old analogue days, orchestras self-limited to aid recording I was told, but these experiences are very old now, so the current musicians probably don't do what their parents and grandparents did in similar recording situations :D
 
Hmm - Are you sure that mics or desks don't have some limiting built in (genuine question, I'm not baiting)? In the past old analogue days, orchestras self-limited to aid recording I was told, but these experiences are very old now, so the current musicians probably don't do what their parents and grandparents did in similar recording situations :D
You mean the recording mics?They usually don't have their limits so low,most of I have seen state 120-130dB range.
I have seen values even higher than that,they of course last ms and it's very indicative that if (A) weighting is applied they show up at vastly lower lower.
That shows that the bulk is down low,which is natural.

Have a look at how the values chance with Amir's reference bass song depending the weighting (except for peaks,that's always (Z) :

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(A) weighting


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(C) weighting

It's the exact same song at the exact same level,what differs is the weighting.
 
How much watt you need depends not only on the sensivity (SPL/M/2.83v) but also on the impendance curve of the speaker. Huge peaks in the impendance curve need a lot of power from the amp to counter that, especially when those occur low in the frequency spectrum. That is what makes that a speaker is "hard to drive" in subjective judgments. Older speakers, even from big companies like JBL have often that issue to a degree. With most modern designs that is less an issue. Sadly engough almost no impendance curves are published in the specs of speakers.

And you also need to count headroom for the amp, especially with chip amps (whatever class) of high power with an SMPS psu. Crown has this good calculator for that on their site to count how much power you need for a certain clean headroom. To be save, a 15dB headroom is what i would take (and i think most). I run my main system (89dB/1m/2.83v) with 150w of power per side now.
 
when I turn up the volume and everything becomes confusing.
how can I understand if it depends on the amplifier, which is no longer there, or on the listening environment?
 
How much watt you need depends not only on the sensivity (SPL/M/2.83v) but also on the impendance curve of the speaker. Huge peaks in the impendance curve need a lot of power from the amp to counter that, especially when those occur low in the frequency spectrum. That is what makes that a speaker is "hard to drive" in subjective judgments. Older speakers, even from big companies like JBL have often that issue to a degree. With most modern designs that is less an issue. Sadly engough almost no impendance curves are published in the specs of speakers.

And you also need to count headroom for the amp, especially with chip amps (whatever class) of high power with an SMPS psu. Crown has this good calculator for that on their site to count how much power you need for a certain clean headroom. To be save, a 15dB headroom is what i would take (and i think most). I run my main system (89dB/1m/2.83v) with 150w of power per side now.
every time i try to use that calculator, nothing happens.
 
when I turn up the volume and everything becomes confusing.
how can I understand if it depends on the amplifier, which is no longer there, or on the listening environment?
can someone tell me something
 
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