Acoustic piano samples-- one key sounds louder than others

[gwise29]

I just received my PX-5S a few days ago and have spent considerable time playing it.   I noticed something right away with the acoustic piano samples: one key-- the G above middle C-- sounds louder than the others.  The same touch/pressure seems to trigger a higher velocity layer on this key.  Naturally, this is quite distracting (I find myself overcompensating by trying to play this key with a lighter touch).

 

I am wondering if this is a problem with my particular unit, or if other users have experienced something similar.  If anyone out there could do a quick check, I would greatly appreciate it!!  (play some runs that include this note, see if it sticks out like a sore thumb).

 

Thanks for your help.

[Display Name]

I haven't been able to duplicate this on my PX-5S. Have you tried initializing?

[Joe Muscara]

If you can connect your PX-5S to a computer and use a program like MIDI-OX (Windows) or MIDI Monitor (Mac), you can see what different keys are outputting.

 

Generally, if this is a physical problem with your PX-5S, you should be able to hear it happening with any sound that is velocity sensitive. If it's only happening with acoustic pianos, I'd agree with Scott's advice, perhaps going so far as to suggest installing the latest firmware (instructions to be found elsewhere on this forum).

[gwise29]

Thanks for your responses.  I recorded a variety of MIDI tracks, and then spent time looking at the velocity levels (acoustic piano sample only).  The note in question (G above middle C) did in fact register about 10% higher than nearby white keys.  Of greater concern, though, is that the black keys (pretty much all of them) register considerably lower than the white keys.  In other words, in order to create the same volume level, greater pressure is needed on the black keys vs the white keys.  As a result, playing this keyboard feels very unnatural to me, especially in comparison to my acoustic piano (an unfair comparison, perhaps).

 

Again, thanks for your help.  My search for the perfect digital piano continues...

[Display Name]

Thanks for your responses.  I recorded a variety of MIDI tracks, and then spent time looking at the velocity levels (acoustic piano sample only).  The note in question (G above middle C) did in fact register about 10% higher than nearby white keys.  Of greater concern, though, is that the black keys (pretty much all of them) register considerably lower than the white keys.  In other words, in order to create the same volume level, greater pressure is needed on the black keys vs the white keys.  As a result, playing this keyboard feels very unnatural to me, especially in comparison to my acoustic piano (an unfair comparison, perhaps).

 

Again, thanks for your help.  My search for the perfect digital piano continues...

 

 

Have you tried adjusting the velocity sensitivity? Adjusting for a different touch may help ""smooth" things out for you.. FWIW, I don't notice any difference between the white/black keys but everyone plays a little differently.  

[Choppin]

@gwise29

 

Hello,

 

No keyboard should have marked differences in the velocity registering if the speed at which the keys are depressed is consistant.  Because of the mechanical nature of the keys, there may be slight differences, but 10% seems a bit much. If you use the bound edge of a fairly solid book, you should be able to press a group of keys at the same velocity.  Test various spots, especially the G key area.  The velocities for those groups should be the same or close to it if you are pressing down evenely.

 

As far as testing Black keys and white keys at the same time, I'm not sure how you would go about that without using something that is rigid (not fingers).  I suppose you could use 2 books taped together or some stepped wood (but you don't want to damage the keyboard) that are offset the exact hight distance between the white and blakc keys. 

 

At any rate, if you see a difference with the G key area test, then your keyboard is likely defective.  If you can, go to a music store and play test a few other keyboards of the same model.

 

When I run hand excercises on the entire length of the PX-5s they come out just as boring and technical as they are supposed to be.  I don't notice any peaks in volume for particular keys.

[Howard Collingsworth]

I have also noticed something like that with G above middle C with the VelOffHarpsi . The upper partials sound rather harsh.

[Gaviles]

I had the same problem but it shifted to different keys. I opened up the whole thing thinking there was something stuck inside affecting the pressure switches. Turns out the plastic housing around the pressure switch seems to create a suction with the lever connected to the key. I'm going to clean and lubricate these touch points to see if that fixes the problem.

[flaviogmaia]

I know this is an old thread, but I noticed the issue gwise29 described above. The black keys don't sound (at least to my ears) at the same volume than nearby white keys. I need to play harder to achieve the same level. This is more pronounced using acoustic piano sounds. I made a test using a piano VST, and achieved the same result. I didn't use any method to test this, just my normal playing. Curious fact: I noticed the same thing when I had a PX-3.

[Brad Saucier]

Been playing my PX-5s for almost 2 years now.  All keys respond as expected.  Keep in mind the keys are not pressure sensitive, they are velocity sensitive.  

[Dave Weiser]

I used to get this kind of feedback on piano samples all the time when I worked for Kurzweil. In fact I got an email about it yesterday (re PC3K) and I don't even work for them anymore!

The thing is... though I've heard from lots of users, they rarely mention the same notes as being problematic. The notes are usually different per user, due to the sound systems/speakers/headphones used for playback. The harmonic content of samples can vary key to key even if volume remains level across the entire range. In the old Kurz PC3 piano sample, a few of the lower notes, like C2, have a lot of high frequencies and certain speakers can *really* accentuate this. The result is a perceived jump in volume even if the levels on a mixer volume meter appear to be consistent.

 

Note - many real pianos have the same kind of characteristic frequency bumps across the keyboard. In the cases of both Kurz and Casio, they likely just captured the character of the actual piano being sampled.

 

The difficulty for all sound designers is that trying to even out these harmonic inconsistencies can have a sterilizing effect on samples, making them sound static and artificial. This static/sterile vibe is something that sound designers are constantly trying to avoid or offset.

 

Usually, in the context of normal playing, a well made piano with a few harmonic inconsistencies will sound fine.

 

Best thing to do in when you run across something like this:

1. Try playing a few different types of music to see where and when the note jumps out and how bad it is.

2. Try listening through something else, anything else. Different speakers, keyboard amp, headphones, etc. This will tell you if or by how much your original listening system is adding to the issue.

3. If your sound system seems to be adding to the exaggerated frequencies, and you happen to use this sound system frequently, you might want to consider a minor global EQ tweak.

This can be done on a most keyboards, or with a mixer or outboard gear. With the PX, I would look at the Stage Setting EQ for the pianos you use, since you might not want the EQ to affect other presets like EPs, strings, organs, etc.

 

Don't worry about the different response between black and white keys. Something would be horribly wrong if they responded the same way. It's just phyics - the lever mechanisms are different sizes. I'm not 100% sure how Casio does it, but as far as I know ALL keyboard manufacturers create separate velocity maps for black and white keys. I've played on test units that *didn't* have the separate maps and it felt absolutely insane.

[gwise29]

Greetings,

 

I see that folks are still responding to my original post, and I appreciate it!  I actually returned my PX-5S over a year ago, as I found my particular unit unplayable (I opted to buy a keyboard from a different manufacturer).  As described earlier, the black keys required greater pressure to produce the same velocity levels.  To test this, I recorded a bunch of music, then checked the MIDI files for velocity levels of each key.  The black keys uniformly registered about 10% lower.

This difference was readily audible.  I asked a friend to sample the keyboard, and she picked up on this issue right away.  Again, not sure if it was just a bad unit or a model-wide problem, but it sounds like "flaviogmaia" is experiencing the same issue.

[Brad Saucier]

Almost 100% sure that a repair was needed in your unit.  We have untold numbers of PX-5s users playing this Privia and many other Privia models without complaint.  I would've recommended having the unit repaired or exchanged.  

[Jokeyman123]

There is no unusual difference in response in my PX350-is actually much better than other weighted digital  pianos I've played where there is a difference-due to the difference in weight and throw of the black vs. white keys and the actions being the same for both-same weights, but shorter pivot point for the black keys. The PX seems to compensate for this by having more weight on the fulcrum arms for the black keys, and it works well on mine at least. I'm also posting because I'm not sure, I'll have to look again, but I seem to see a slightly different physical construction in the PX5s compared to my PX350 based on Gaviles posted picture. I could be wrong, I'll have to look again. I've always thought the actiuons were identical.

[Brad Saucier]

The PX-5s and PX-350 action should be identically constructed.  It's part of how Casio keeps cost low.  The entire Privia series shares the one action.  

[Dave Weiser]

I just caught the fact that the note in question was spitting out velocity values inconsistent with the *other white notes*.

D'oh!

[flaviogmaia]

Dave Weiser suggested thet the issue might be the different harmonics of each key, as they were sampled. So yesterday I downloaded a demo of Pianoteq. Being modeled, and not sampled, I thought the issue would be minimized. Guess what? No issue at all. 

 

I play at home mainly through headphones (not top quality), and I noticed some other black keys were exhibiting the same behaviour through the sound system (really NOT good quality) at a wedding I played on Saturday, but not at home. So I guess that's it. Thanks for the tips, Dave!

[mik pointe]

I just want to add my experience to this thread.  I've played 3 perfectly working privias ( Px860, px160, px 850 again) and one that had this irritating Keboardwide issue of the black keys being uniformly softer than the white keys.  I discovered only that the issue wasn't in the keys themselves (I swapped out keys), nor in the brains of the keyboard, but instead somewhere in the entire plastic piece that holds the action/hammers/sensors etc.  I swapped out a working plastic key bed with everything attached ,  with the one that worked fine, and the keyboards switched issues.  

I'm reluctant to pay a bench fee but I'd really love to find out what in the world the problem is.  It's not a difference in sampling or whatever, as some people have suggested.  It's some problem, perhaps in the hammers, of perhaps in the off-white plastic piece itself that holds the action. If I ever figure it out I'll try and post it to every post where I see this issue.  Right now I suspect it is some kind of defective main keybed in a tiny batch of privias due to poor quality control. The shame is that very inexperienced players won't detect it. It's also less noticeable at lower volumes. So if you are in a rush like I was, you can end up with a lemon from someone who didn't know the difference, that's out of warranty.

[Jokeyman123]

Here's another thought-I've had several Casios (and other keybeds) apart over the years.  there will be a natural tendency for the black keys to have a different physical response due to their overall length.

 

One of the challenges in my classical studies was to overcome this-prqcticing scales, arpeggios etc. throughout all keys and the trick was to keep a balanced sound throughout the key ranges, not an easy task. If anything, being careful not to overstrike the black keys on an acoustic piano will always be a challenge to to the physical structure of the keys. However, on a decently "regulated" piano the difference should be minor if at all between black and white keys. But it will still be there.

 

There may be another reason for this imbalance in the Privia, although again I haven't noticed it much on mine (PX-350, PX-575 and PX-560). If there is, the culprit may be the felts that are buffering keystrikes in both directions up and down. If there are not equal amounts of wear, or in the assembly process unequal amounts of felt were used-different felts for the black than for the white-this could create a difference in keythrow depth and therefore dynamic response. I would find it a stretch that the nylon or whatever rigid plastic from Privia to Privia would e defective, or we would hear of a huge batch of these with the same problem-these are mass-manufactured I'm sure like cars on an assembly line. We are not getting Steinways assembled one at a time by hand! 

 

As far as one key being more pronounced, if the key is slightly out of line with the tri-sensore rubber boot underneath, or if there is a slight defect or contamination in or above the boot, this can radically affect the dynamic response. the tolerances between the 3 sensors is so small, if everything is not hitting exactly right, there will be an audible difference in the tones among the keys affected. Part of the reason i know anything at all about this is as a professional player and educator with limited (or no) budget-I had to teach myself to be my own piano technician-after realizing I could not afford to hire one-and this was before quality digitals came to market. Hope this helps someone! Off to work.