Kawai CN 33. Sound issue.

Posted by: Recaredo

Kawai CN 33. Sound issue. - 09/07/12 01:42 PM

I’m very happy with my Kawai CN 33, but now it has got a sound issue. Some keys make an odd sound, like this:


https://www.box.com/s/lxyhmgpp937qr7ymsbrp


This sound does not appear when I use headphones, so I think it’s produced by some internal pieces. These sounds are really distracting when I’m playing the piano.

I’d like to know whether this is normal or I’ll have to call the dealer. The piano is still under warranty.
Posted by: Kawai James

Re: Kawai CN 33. Sound issue. - 09/07/12 05:05 PM

Recaredo, if the problem does not occur with headphones, it's likely that the instrument's speakers are the source. Actually, this sounds like a vibration/resonance inside the piano cabinet, or possibly something else in the room.

Try repositioning the instrument a little, and clearing the top surface of any artefacts you may have placed there. You may also wish to try looking underneath the keyboard to check if the sound is coming from one speaker in particular.

If you are unable to resolve the issue yourself, I would certainly give the dealer a call and ask for a technician to visit your home to investigate further.

Kind regards,
James
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Posted by: spanishbuddha

Re: Kawai CN 33. Sound issue. - 09/07/12 05:46 PM

Ooh sounds strange. Like extra reverb on some notes. Does sound like a defect though, but James ideas of moving the 33 is a good one. I had a buzz, on one note only, not in headphones, and I just could not track it down. I've now moved my 33 to another room and the buzz is gone.
Posted by: ozzienovice

Re: Kawai CN 33. Sound issue. - 09/07/12 09:22 PM

I had an annoying resonance on notes in lower register on my CN33. I traced to the back panel vibrating against the main body. I fixed it by inserting a few thin pieces of cardboard between the panel and body. You can easily test if it is back panel by pushing on while playing notes that ring.
Posted by: Recaredo

Re: Kawai CN 33. Sound issue. - 09/08/12 03:50 PM

Thanks guys for your replies!

I’ve done some tests according to your suggestions, but sadly the sound is the same. I believe those sounds come up from the cabinet; probably some internal parts make that resonance.


I’ll call the dealer. I hope the repair is easy… crossing fingers.


Thanks again.
Posted by: Recaredo

Re: Kawai CN 33. Sound issue. - 11/09/12 05:50 AM

Hi!

I wanted to update this issue about my Kawai.

I called the dealer to tell him the problem, and he understood the piano had to be fixed under warranty.

So a technician was at my home to try to solve the issue. He opened the piano top lid and checked all internal parts and screws. The odd sound had disappeared.

But when the technician closed the top lid and tightened its screws, the resonances started sounding again. The guy didn’t know what to do to solve this problem, and said to me that he could try to find a solution.

Later the technician came to my home again. He opened the piano top lid and put some felt pieces under this lid; but this solution didn’t work either, the sound was the same.

Then the dealer told me that he had to take the piano to his workshop, since he had to disassemble each and every part of the piano, to find the problem and fix it. I couldn’t believe this repair was so complicated.

In the meanwhile, some keys developed clanky noises, particularly the central octaves. The dealer told me that this problem could be fixed applying extra grease in the key mechanisms, but probably some keys would have to be replaced.

The piano was sent to the dealer’s workshop yesterday. Yes, this seems to be a “piano nightmare”. I just hope the piano is well repaired soon.

Regards!
Posted by: Recaredo

Re: Kawai CN 33. Sound issue. - 11/14/12 01:30 PM

Hi again!

My piano is back. The repair service has been really fast, although the result has not been completely satisfactory.

The good news.

Extra grease was applied on key mechanisms and the clanky noises have disappeared. Great!

The bad news.

The resonance noises are still there. I tried out the piano at the workshop, after it was repaired, and I didn’t hear any noise. However, when the piano arrived at home, these noises appeared again. Then the technician and I put the piano in different rooms, but these resonances continued sounding, so I still believe they come up from the interior of the piano.

The dealer claims they checked every part of the piano and found all was right. I trust him, but I’d like to solve this uncanny issue. Any suggestion will be extremely appreciated.
Posted by: spanishbuddha

Re: Kawai CN 33. Sound issue. - 11/14/12 01:46 PM

Intermittent problem that comes and goes depending when top removed replaced, and piano moved to workshop and back. Something is loose or rubbing.

With the technician, or not (!) take the top off (four screws at back) slide forward, and see if it disappears again.

If not see if you can determine inside what is vibrating/resonating.

If it goes with top off, slide it on but don't screw. Still gone? One screw at a time. Maybe something with the cabinet is distorting under tension.

Just like real pianos tracking down buzzes, rattles, squeaks, resonances can be very difficult.

Another idea, reroute the pedal and power cables, or at least leave them hanging loose.

Another idea, wedge the sliding key cover open with some foam. Also, when the top is off check the screws holding the 'gear' mechanism is are tight.

Good luck.
Posted by: Recaredo

Re: Kawai CN 33. Sound issue. - 11/14/12 02:05 PM

Thanks Spanishbuddha! I think I can do those tests you comment.
Posted by: JFP

Re: Kawai CN 33. Sound issue. - 11/15/12 05:19 AM

It's not over headphones . The cabinet has been disassembled and checked a few times and tightened up. No resonances in the room either. So check if the sound is coming from the speakers again. Sounds a bit like a broken speaker to me. Could be that it is not entirely broken, but the distortions is especially triggered in certain frequency ranges. By the way does this also happen a low volumes, or only from a certain volume setting and up ? If the cabinet seems ok, I would certainly check teh speakers again.

Test: choose the most 'dry' program possible , turn off all reverbs and effects. Play some notes that trigger the distortion (no pedals) and lift up suddenly. Listen to what the speaker is doing. Does it die away immediately when you release the notes , or does it ring on for a while (then it cant be the speakers, because they go mute when there is no longer a signal) ?

Sorry to hear about your problem. Was there an incident after which it started making these sounds ? (Something hit the piano, fell on it , glass of water over the cabinet ?, piano was moved ?)
Posted by: Recaredo

Re: Kawai CN 33. Sound issue. - 11/15/12 08:01 AM

Hi JFP!

No, the piano has not suffered any incident at home, and it came perfectly packed when I bought it, now one year ago. Two technicians assembled it at my home. The service was really good.


The dealer has called me this morning. He is worried about this issue and wants to solve it. So his technician is coming to my home this afternoon to check the piano again. I’ll tell him all your suggestions.

Thanks so much for your replies, guys.
Posted by: Recaredo

Re: Kawai CN 33. Sound issue. - 11/15/12 01:22 PM

Good news!


This afternoon the technician has put a strip of foam between the back cover and the top lid, and it’s worked. Now the resonances have disappeared completely. I’m really happy. Here you can hear the final result.

https://www.box.com/s/jmk8bk6g6te11mu96mvl

Thanks again for your suggestions and for being so patient with this thread0
Posted by: spanishbuddha

Re: Kawai CN 33. Sound issue. - 11/15/12 01:42 PM

Result. Congrats, enjoy again your 33.
Posted by: BeccaBb

Re: Kawai CN 33. Sound issue. - 11/15/12 03:02 PM

YAY! Congrats Recaredo! smile Happy Playing!
Posted by: Kawai James

Re: Kawai CN 33. Sound issue. - 11/15/12 04:13 PM

Result! wink

James
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