Why not the piano as a reference for bass

@audiokinesis 

I was once tasked with designing a speaker system for amplifying electric piano

No doubt the electric piano was attempting to sound like a real piano?  When I play the lowest note on an acoustic piano, the amount of sound energy output is pretty directly related to how quickly I press the key.  There is no artificial limit, and no shortage of sound either.

The key mechanism is mechanical, not some electronic switch or sensor.  And the whole piano resonates

@richardbrand , my investigation into the loudness of the fundamentals and first few overtones of the lowest piano notes was based on the spectra of those notes played on a grand piano, as I figured that would be applicable to amplified electric piano.

I presume the electric piano was "attempting to sound like a real piano".  My  customer said that he used the same model electric piano as Elton John.  He mentioned it to me but I don't remember the specific model.  I think it was a Yamaha. 

@audiokinesis 

Thanks for the clarification!

I don’t agree that the low notes on a modern grand piano (piano-forte or soft-loud) contain so little energy that they do not merit being reproduced.  Bosendorfer and Stuart keep extending the keyboard downwards!  I don’t think Beethoven would have agreed either - he was very quick to extend the range he wrote for when gifted pianos which went further up and down!

There is of course a fundamental difficulty in judging sound quality against amplified sources - there is no original to compare to.

Anyway, I use soft piano music to judge atmospherics and double bass for bass impact ... but the main thing is to enjoy your music

@richardbrand wrote: "I don’t agree that the low notes on a modern grand piano (piano-forte or soft-loud) contain so little energy that they do not merit being reproduced.  Bosendorfer and Stuart keep extending the keyboard downwards!"

Just to be clear, I’m not saying that the lowest notes on a normal grand piano contain so little energy that they do not merit being reproduced. 

I’m saying that the lowest fundamentals (and sometimes the corresponding first overtones) of the lowest notes of a non-Bosendorfer grand piano contain so little energy that they do not merit being reproduced in a live music setting. 

I don’t know whether this is a grand piano or not, but it shows the spectra of the lowest notes starting with A0.  Pause it after each note and look at how much energy is in the fundamental and first overtone:

piano sound spectrum - YouTube

Anyone else interested in why piano might or might not be a good instrument for evaluating a speaker’s bass response is invited to do the same.   There’s just not a whole lot of true low bass energy. 

@audiokinesis

piano sound spectrum - YouTube

From the comments, the guy who posted that video had no idea what microphone was used, let alone what piano or where the microphone was positioned! 

What I do find interesting is the low modes that are excited when high pitch notes are played.  As I wrote above, the whole piano resonates - after all, it is filled with more than 88 tuned resonators and felt can only damp so much.

Sure the low notes also carry a lot of harmonics, which is why the piano sounds like a piano and not like a pure pipe organ. Agreed, many people may not hear the fundamentals of low notes, and few indeed will directly hear the 16-Hz fundamental of a 108-key Stuart piano's lowest note.  Few subwoofers will even go close with any sort of accuracy. Same goes for the 8-Hz fundamental of Sydney Town Hall's organ with its 64 foot long Gravissima pipe.  You can't hear it but you can certainly feel it!