Piano design and bass tone

Lately, I've been scouring the web with the routine of a Google web crawler for anything piano related. It's amazing how much you can learn in as little as 4 months. More amazing still, is how much you still don't know even after longer periods of time, and the times where you lose basic facts in a sea of technicalities and complexities (I christen it "the lawyer's dilemma"). I'm writing in the "no-man's land" dividing regular power-users and experts alike. I hope to learn from this discussion.

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Bass Tone

A very important part of my (unfinished) compositions is the use of the contra and subcontra octaves ("bass notes") to add power to certain passages requiring a cathartic energy to them. There is no moment where I forget opportunities to add those extra low notes either to experiment or fit the theme I'm going for. If the low strings by themselves don't sound "right" to me, in compositions requiring single note solos, it breaks immersion from the piece and brings too close the limitations of Pianoteq to my discerning, but biased mind.

Here we have the case of the "Steinway" D4 model. Without any changes, the piano sounds fantastically real. The tenor, alto, and treble sections are physically indistinguishable ("oh, a piano string could sound like that in real life") from their real world counterparts, and the bass notes sound plausibly correct, except when you change the piano length. That's when the low notes fall apart for me, at least at a psychological level. The spectral profile of the bass strings don't sound like any other piano in existence. From what I observed, the bass octaves are much more dependent on inharmonicity to sound similar to a real piano, rather than the strings' tone sans the inharmonics. This isn't a bad thing; after all, why copy the piano verbatim? Sometimes it's better to diverge, but I want to know what goes into designing the low octaves' overall sound and what compromises must be made to make it sound "right"?

The C3, on the other hand, has a sound in the bass which sounds much more plausible, at least to me, at any string length. I am more easily reminded of pianos such as the Klavins 370 (at 5 meters) and a Fazioli F308 (string diameter set at "D" size) and possibly many more. What the older model loses, unfortunately, is the brilliant attack and nigh-perfect resonance of the D4, as well as the enhancements a version 4 model would employ, since it is merely ported to the new engine (correct me if I'm wrong about that fact). I find myself switching between the C3 and D4 to get both their best qualities instead of exploring different sound palettes.

Sure, .fxps can change a lot of the piano's sound, but I suspect they can't eliminate the intrinsic character of the strings, so an E1 (41hz) on the D4 will never sound "similar" to an E1 on the C3.

I am very interested to hear one of the staff's opinion on this particular matter.

Vertical String Termination

This one is more of a sonority issue, since piano sustain can be easily changed by the developers to emulate the decay of a Stuart & Sons or a Steingraeber. However, bass chords still sound cacophonous and rough. Terminating the string vertically at both ends really opens up the sound palette and allows chords to be played in any register, without muddiness. All other consequences of such a bridge agraffe can be changed in the interface (dynamics, soundboard impedance, etc.).

I wonder if you are considering borrowing, ordering, or visiting a Stuart or a Steingraeber to serve as a reference for either:

• A D4 fitted with bridge agraffes

• A recreation of either of these piano brands

• A new model designed entirely from scratch

to test the influence of elliptical polarization on such a model. If you are, a windfall for us. If not, we can wait.

Treble Strings Across the Board

This idea was pioneered by DIY juggernaut Adrian Mann, who liked the sound of long treble strings tuned to bass frequencies. His 5.7 meter piano only starts using bichords past low D, and none of the strings are wrapped. The character of the low notes is simply unique. See this video for an example of the sound.

I tried setting the diapason down an octave to get the character of the higher strings sounding at lower notes, but while the "sound" was there, the instrument was muffled to hell and back because of this extreme setting. You simply can't match the character of Mann's piano just by changing the string length.
If, by chance or the passage of time, we can alter the number of strings per note and optionally wrap them if we so desire, that would be an ideal solution, provided if you can manage your goal of opening up the sound model even more.

Have you tried an idea similar to the heading of this subject?
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EDIT: Changed "Bass Tone" to actually ask something.