Topic: Initial Touch - Mi note sounds louder than other notes

[MARCOS FERREIRA]

I have a Tyros 5 76 keys. The following is happening: when "INITIAL TOUCH" is on, the "Mi" ("E") notes sound very loudly across the keyboard. It does not obey touch. When I turn "INITIAL TOUCH" off, all notes sound at the same volume. Has anyone been through this? Thank you in advance for your attention.

[Ed B]

Hi
See page 7 of the reference manual which outlines how to set up touch. Some instruments such as organ do not have touch control. You have control over each keyboard part as well.
Regards
Ed B

[overover]

I have a Tyros 5 76 keys. The following is happening: when "INITIAL TOUCH" is on, the "Mi" ("E") notes sound very loudly across the keyboard. It does not obey touch. When I turn "INITIAL TOUCH" off, all notes sound at the same volume. Has anyone been through this? Thank you in advance for your attention.

Hi Marcos,

in this case (only one particular Note sounds with FULL VELOCITY in ALL OCTAVES, while all the other keys can be played with "Initial Touch"), probably there is a problem with the so called "Key Scanner" (on circuit board "EMKS"), or maybe there is a problem with the so called "Key Matrix" ("MK*" circuit boards).

I'm afraid you can't do anything yourself in this case. You should contact an authorized Yamaha Service Center.


Best regards,
Chris

[MARCOS FERREIRA]

Thanks, I found that the Bb note also has the same symptom. I tested several voices, such as piano, guitar and the result is the same. I think the problem is really technical and not configuration. I appreciate help.

[valio7771]

Thanks, I found that the Bb note also has the same symptom. I tested several voices, such as piano, guitar and the result is the same. I think the problem is really technical and not configuration. I appreciate help.

I'm quite certain that it's a software problem. This is a fairly common issue in all keyboards general not just with Tyros. It may be caused by dust or humidity, but to me it sounds like it's worn rubber contact under those faulty keys, it have to be taken to a specialist to repair it. You can do it yourself, but you need to have the replacement rubber contacts, they are usually sold for an entire octave not for individual keys, and of coarse you need to know what are you doing, so I won not recommend that if you're not sure in your own repairing abilities.


This it what they look like

[overover]

... to me it sounds like it's worn rubber contact under those faulty keys, ...

Hi Valio,

I don't think it could be the Rubber Contacts in this case, because Marcos originally wrote, the Problem affects ALL "E" notes across the keyboard, and when "Initial Touch" is turned OFF, all notes sound OK:

I have a Tyros 5 76 keys. The following is happening: when "INITIAL TOUCH" is on, the "Mi" ("E") notes sound very loudly across the keyboard. It does not obey touch. When I turn "INITIAL TOUCH" off, all notes sound at the same volume. ...

In my experience, this symptom (error on a note, but in all octaves) usually indicates a faulty "Key Scanner" circuit, or maybe there is something wrong with the "Key Matrix", as mentioned before.

If there was a problem with the Rubber Contacts, it would not affect a certain note in all octaves, I think.


Best regards,
Chris

[valio7771]

Hi Valio,

I don't think it could be the Rubber Contacts in this case, because Marcos originally wrote, the Problem affects ALL "E" notes across the keyboard, and when "Initial Touch" is turned OFF, all notes sound OK:

In my experience, this symptom (error on a note, but in all octaves) usually indicates a faulty "Key Scanner" circuit, or maybe there is something wrong with the "Key Matrix", as mentioned before.

If there was a problem with the Rubber Contacts, it would not affect a certain note in all octaves, I think.


Best regards,
Chris

Oh, I somehow ignored the 'accros the whole keyboard' part. Yes, you're probably right about the key scanner circuit.  Thanks for pointing that out!

[MARCOS FERREIRA]

Hello, Overover and Valio7771,thanks for your help. In addition to the symptoms I have already mentioned, the following is also happening:
1-When I play the E7 chord the keyboard plays the E7#11  chord and shows this chord on the display.
2-When I touch the B3 key, the Bb3 key also sounds. Remembering that the Bb3 key is the # 11 key on the E7 chord and that, even without pressing it, it sounds together with the E7 chord.
3-I have a little skill in fixing things and have already fixed other Yamaha keyboards.
4-I saw some videos on Youtube showing how to open and clean the rubbers and keys. I did the whole procedure. There was almost no dirt and the rubbers are apparently in good condition. The Tyros 5 is only 2 years old. It did not solve either of the 2 symptoms.
5-I saw a video showing the use of WD-40 in contacts, with a positive result. I used the WD-40 only on the contacts of the B3 and Bb3 keys and tested the keyboard for about 20 minutes and there was no error in the E7 chord. But Bb and E continue to have the same symptom. I plan on using the WD-40 on all contacts.
6-Thank you very much for your help. I live in Brazil and here in my city there is no Yamaha technical assistance. Any other help is most welcome.

[MARCOS FERREIRA]

See the photos

[attachment deleted by admin]

[overover]

Hi Marcos,

according to your description, I do NOT think that it is due to the key contacts. As already described above, it could be due to the Key Scanner IC (which queries the key contacts) or to the Key Matrix (a diode matrix via which the key contacts are connected to the Key Scanner IC).

The only thing you could do yourself, in my opinion, is to check all the ribbon cables / multi pin connectors near the circuit boards "MK76L", "MKC", "MKH" and "EMKS" (for a simple "contact problem" to be excluded).


And please be very careful when cleaning the key contacts and the rubber contacts. I do NOT recommend to use "WD-40"! Such oily products should NOT be used for electronic devices. If you damage the carbon layer of the contacts on the circuit boards or on the rubber strips, a further repair will certainly be very expensive.


Unfortunately, due to your description, I have no better news for you. This is probably a case for a service technician who is familiar with Yamaha keyboards.


P.S.
To narrow the problem down a bit, you could connect an external MIDI keyboard to the T5:

Select the MIDI template "All Parts" on the T5 and connect the MIDI keyboard to "MIDI B IN". Set the transmission channel of the external keyboard to CH 1. If everything works normally in connection with the external keyboard, the problem is at least limited to the internal keyboard (and thus truly to the mentioned sources of error "Key Scanner IC" or "Key Matrix").


Best regards.
Chris

[MARCOS FERREIRA]

Ok Chris, thanks for your valuable collaboration.

[fischnek]

Marcos, may I ask, what was the final solution on this problem? I have similar issues. Thanks.

[MARCOS FERREIRA]

Hello fischnek, I found a very good technician here in my city and he identified the defect. It was in the DIODES. He replaced the diodes and everything was ok. It has been almost 3 years now and everything is ok. good luck to you.