Hi Phil,
Each piano in a showroom will be slightly different to the next and it's probable that some character in those frequencies existed in the piano which was modeled.
I don't hear something incorrect - but if I wish to make any piano "cleaner" (for wont of a better word) from real world artifacts, here are some things I'd look to first:
Firstly, outside of Piantoeq, just be sure treble on your audio system is not overly-boosted. More about this can be written but essentially, small speakers or consumer grade equipment can often push bass and trebles to "sweeten" overall consumer experience - but can also push too much treble or make bass too boomy. Factor in non-acoustically treated bedrooms/home studios etc. and nobody's space sounds the same - not witch-craft, it's factual stuff - you may get great results after you alter your external EQ! - not a drill.
So, if you have some controls over this, try altering bass, mid-range and treble settings to something closer to a flatter line (at least lessen some of the pushed elements until it sounds less "candy" or "tinny" or "booming").
To Pianoteq..
In Stage:
Why? There may be much work on getting your best velocity curve but sometimes just selecting "moderately fast" can make a positive difference as a starting point at least to evaluate (if that's heading the wrong way for your keyboard and/or style, try "moderately slow" and take it from there). For a lot of people this may be regrettably overlooked - AND can be the single most important setting you will make - take good chunks of time to experiment with the curve, search the Pianoteq curves page to view curves for your keyboard, attempt (even many times over months) going through the calibration routing because one day you may totally have an Eureka moment etc. But for many, a harsh curve can make any notes you play ALL sound too "CLIPPY!!!" (ahh!) and forcing mostly frequencies best reserved for genuinely FFF velocities - if you play like that, then it may come down to getting some more experience, lessons or know that with more time your playing (expression etc.) will improve. Get the velocity curve somewhere closer to "real" and the rest may be so much better..
but if you're already cool with all that, some other more instant things to try in Pianoteq Stage:
Increase Dynamics (slider under volume) - this can breath more life with a click - making your playing and all the sounds more real without doing anything else in Pianoteq.. the Steinway Model B "Bright" preset has a low-ish dynamic setting of 38.. if I want something more like a concert grand "feel" for some expressive playing I might raise that number to more like either side of 50 - raising this number has a nice side effect of reducing "harsh" over-playing in terms of velocity. Many people may make a fine career from playing all things at high velocity but learning about playing with some expressive intent can NOT hurt - even the best students may eventually understand this - and even those free-ranging it too might eventually realise "Oh yeah, you can get so much more from playing soft, then hard".. it's not rocket science - but it is overlooked IMO - nobody needs to play every note over 70 velocity.. always worth considering if skills are not yet developed.. advice along those lines MIGHT just save some people even quite a few years on their development, if they have no tutoring or just watch Youtube videos
Turn off "Delay" (button lower right)
Turn off or lower "Reverb"
Click "Action" button and lower "Key Release" and "Sustain Pedal" noise
Try turning down some of the treble in EQU3 in "Effects" - drag the dot down some
Click "Equalizer" and create a roll-off on trebles by clicking the line at around 8000 and then add another dot at far right, then gently drag that down about -2dB or -5dB and alter the dot at 8000 to something like 10000 etc. - experiment
Don't overlook lowering or turning off reverb! - experiment at least a little with this setting - try changing the reverb tone as well - it may be all you want to do and work for your room space and/or headphones better than other things here
In Standard and Pro:
There are many more things possible reaching into much more depth but just GENTLY applying some of the above may be all you want to do.
Just some quick examples (without so much detail) of extra one-hit things you could do as well as the above with Standard and Pro which may touch on such audio artifacts in interesting ways - one could spend much time balancing all these together gently:
Slightly lengthen strings to roll off all kinds of overtone interactions
Change microphones (plenty of presets - maybe choose ones further away from piano so there's less detail in "up close" squeaks and hammer hits). This is extensive in scope and there's so much you can do with mics, it is phenomenal IMO
Lower Impedance (cabinet resonance)
Lower Cutoff (less high frequencies processed)
Raise Q factor (high frequencies diminish faster)
Lower Sympathetic resonance (less resonance from neighboring strings')
Lower Duplex scale (less complex resonance in mostly high frequencies)
Add 0.07 or less to Energy, leave inertia or maybe shorten (personally I like this for taking some initial transient burst away YMMV with each thing you're trying to accomplish - always worth taking this little detour IMO
In "Action" panel, alter all (things like damper position and duration can make a more clean sound, like removing some felt touching strings which might lessen some overtones - lots of details in that panel
Lower hammer noise (I do like to do this, may result = more "recorded piano" type result than real life "player" position preset though
Lower Hammer hardness - maybe begin with one mouse scroll down per Piano/Mezzo/Forte
Turn off (or alter) compression
Changes to Unison width can alter how frequencies work together - try higher and lower, using slider or precise numbers
Add a little Octave stretching - see if that helps - it can sweeten or sour in interesting ways
Alter Direct sound duration. Longer or shorter might work - worth carefully adjusting this esp. after changing a lot of other things
Also, overlooked maybe a lot, right-click "Unison width" and change "Unison Balance" from 0 to something like 0.8 - give time to it, try way different numbers
Widen Dynamics (slider right) for often breathing more life into the playing and therefore the "canvass" you're working on.. you may over time realize you make nicer sounds by playing less hard and with less velocity overall, the accents of higher velocities will stand out - in which case those may (like a real piano) work better without all the other tweaking anyhoo
Those are most of the quick go-to settings in the main interface to balance and alter - but under the hood, you have some 30 different settings which can be applied on a note by note basis, drawn in, given randomized values and so on - to totally just swing something on notes or ranges of notes alone if you need.
The ability in Pro to really gain reach into things like spectrum profile and on an individual note basis - amazing.. any "zing" or transient you want to accentuate or disappear = doable. Learning curve is high but not impossible for most people with some serious intent in their music making.
Nothing like Pianoteq is possible elsewhere in my experience for playing (from practice to performance) and through to recording (like working with a real piano in a studio - better in some obvious ways) and certainly nothing pertaining to such high levels of reality and so vividly - but in short, with time spent you can learn how to do almost anything you want to a piano preset's sound. Make a bright piano dark - make something completely new - with some experimenting, reading, learning you can make a lot of advances - and I encourage anyone to get into the settings and try them out - break some things, learn why, back them off or start again.. make some smaller changes and eventually you'll learn what things you like to do to get the best sound in your space (or for recording with whatever intentional professional outcomes are required).
Even with just the above, and even with Stage, you can still do a lot
Worth searching this forum for other threads about editing Pianoteq presets also - going back many years people have posted about what changes they want to make and asking similar things.
Hope that's a help for anyone thinking about how to edit presets in Pianoteq. Just do the opposite of these above things, if you want to make a darker sounding preset brighter.
Pianoteq Studio Bundle (Pro plus all instruments) - Kawai MP11 digital piano - Yamaha HS8 monitors