Speaker on keyboard not working. What could it be?

Posted by: chony

Speaker on keyboard not working. What could it be? - 07/17/05 01:27 AM

Hi all,

The right side speaker on my old PSR-8000 has suddenly quit on me. No crackles or pops - it just one day stopped working. I opened up the keyboard and everything including the connections seem to be intact.

Does anyone have experience with this?

I assume the problem could either be on the circuit board - which is where the speaker is attached to; or the speaker itself. If it is the latter, I'll replace it; if the former, I guess not... How can I test it? And does anyone know where to get a replacement speaker for a PSR 8000?

Thanks everyone! Chony.
Posted by: chony

Re: Speaker on keyboard not working. What could it be? - 07/17/05 01:56 AM

A bit more info: I took out the speaker and on the back it says:

4ohms . 20W . Japan . 7L1 . XU089A0 .

I don't know what company makes it, so it makes it hard to look up. Without measuring it looks like a 5" speaker (the specs say 16cm).

[This message has been edited by chony (edited 07-17-2005).]
Posted by: Roel

Re: Speaker on keyboard not working. What could it be? - 07/17/05 03:49 AM

The test is easy :
Just switch the speaker-wires/connectors on the board.
If the same speaker remains 'dead' it IS the speaker.
If the original 'defective' speaker works now the problem is on the board (amplifier or fuse).

What about the headphone.... does it work on both channels ?

[This message has been edited by Roel (edited 07-17-2005).]
Posted by: travlin'easy

Re: Speaker on keyboard not working. What could it be? - 07/17/05 06:32 AM

Chony,

Roel is right on the money! Additionally, does the stereo output function when hooked up to a PA system? If the headphones and stereo output works, the culprit is likely the speaker, however, Roel's test will determine this.

If the speaker must be replaced, any speaker rated at 4-ohms with the same physical measurements will work just fine.

Good Luck,

Gary

------------------
Travlin' Easy
Posted by: loungelyzard

Re: Speaker on keyboard not working. What could it be? - 07/17/05 07:27 AM

Chony:
check your settings, maybe it got set to L Main and R sub or some combination or something?? just trying to think of something, usually speakers keep working. Have you tried initial set up reset??..pose
Posted by: msutliff

Re: Speaker on keyboard not working. What could it be? - 07/17/05 08:05 AM

Quote:
Originally posted by Roel:
What about the headphone....


And speaking of the headphone jack, I had somthing very similar happen on my keyboard (GEM WK8), all of a sudden, no sound out of the right side. Turned out to be the headphone jack, it didn't re-connect the speaker when I pulled the headphone plug out (sticky or dirty contact points?). Both channels worked with the headphones plugged in, both channels worked when connected to an external PA. I pulled out the plug on the headphones and got some cracklin' out of the right side speaker. I inserted and pulled out again and the right side came back.

I haven't plugged in the headphones since....

-mike
Posted by: chony

Re: Speaker on keyboard not working. What could it be? - 07/17/05 06:55 PM

Hmmm,

I did as you all instructed. I cleaned out the headphone jack - and it seems to be working along with the PA outputs.

Without changing the wires however, I realized that the problem is not with the speaker, as the right hand tweeter - which is not connected to the woofer - is also not working.

Roel, what do you mean that the problem would therefore be with the amp of fuse. Is there any way for me to check or change the fuse?

Thanks!
Chony
Posted by: quietDIN

Re: Speaker on keyboard not working. What could it be? - 07/17/05 09:32 PM

Quote:
Originally posted by chony:
I did as you all instructed. I cleaned out the headphone jack - and it seems to be working along with the PA outputs.

Without changing the wires however, I realized that the problem is not with the speaker, as the right hand tweeter - which is not connected to the woofer - is also not working.


Based on what you said, it seems likely that (as Mike mentioned) one side of your headphone jack's speaker-switching contacts are not working. Don't be convinced otherwise just because headphones work on both channels; they will, even if a speaker connection isn't properly made when the headphone plug is removed. How did you clean the headphone jack?

Of course, it's remotely possible that both the woofer and tweeter are bad on one side, but that's less plausible than the headphone jack switch contacts acting up.

--Barry
Posted by: chony

Re: Speaker on keyboard not working. What could it be? - 07/17/05 09:48 PM

Thanks Barry,

I figured that maybe the power (fuse / amp) for both the woofer and tweeter, were powered from the same source - and that that source might be the problem.

I 'cleaned' the headphone socket with pressurized air, with cotton buds, and inserted a plug in ten or twenty times!

Chony

[This message has been edited by chony (edited 07-17-2005).]
Posted by: travlin'easy

Re: Speaker on keyboard not working. What could it be? - 07/18/05 05:48 AM

Chony,

If the proble is the leaf-switch contacts within the headphone jack, then clearning it with cotton swabs and canned air will not correct this problem because the swabs cannot get between the switch contacts.

If the headphone output and normal stereo output is working just fine, then the problem may be one of the headphone jack's leaf switches. The only way to check this out is to open the keyboard, then connect a small jumper to the switch, thus bypassing the contacts. If this activates the speakers, then the problem can readily be solved by replacing the headphone jack. This type of jack is available at most electronics stores for under $3.

Gary
Posted by: chony

Re: Speaker on keyboard not working. What could it be? - 07/18/05 08:26 AM

Thanks Gary,

Don't mind my ignorance - but I'm not sure what the 'leaf switch' is, nor how to bypass it.

I called Yamaha, and they said they have the spare part for $100. I can't just buy the $3 socket as it is welded into the board and connected to at least four points on that board. I don't really want to put that kind of money into my backup keyboard...

I did pull out the plug to the whole headphone section - but all that did was disable all four of the speakers.

Thanks, Chony.
Posted by: quietDIN

Re: Speaker on keyboard not working. What could it be? - 07/18/05 08:57 AM

Quote:
Originally posted by chony:
Thanks Barry,

I figured that maybe the power (fuse / amp) for both the woofer and tweeter, were powered from the same source - and that that source might be the problem.

I 'cleaned' the headphone socket with pressurized air, with cotton buds, and inserted a plug in ten or twenty times!

Chony,
You're welcome; hopefully we can help you figure out what the problem is.

As Gary said, what you did to clean the headphone jack might not do the trick. The jack contacts are "springy", and normally held closed when no plug is inserted. That, and their positioning in the jack, makes cleaning them somewhat difficult. Also, I've experienced metal fatigue/fracture in jack switch contacts, causing them to no longer make contact; no amount of cleaning will fix that.

If the jack is accessible, and you can determine which contacts to short together, what Gary suggested is the way to diagnose the jack. I don't know any details of the
8000's headphone jack arrangement; in fact,
headphone jacks come in various forms, with some having wires soldered directly while others are mounted to a pc board. (BTW, if it's on a pc board, you might check for a possibly bad solder connection there.) A switching-type headphone jack typically has 5 connections; one of them is common (ground), and connects to a plug's sleeve when it's inserted. Two would connect to a plug's tip and ring, and the remaining two are the L & R speaker-switch connections. If you can't determine which are which, I'd suggest NOT randomly jumping them to troubleshoot the problem.

I mentioned the chance (unlikely though it is) of both tweeter and woofer being out because it's not impossible. In fact, what sometimes happens is that a tweeter fails first, but it isn't immediately noticed. (Please don't take this as a reflection on your hearing or powers of observation!) Then, when the woofer goes, it becomes very obvious, because the entire side is out. Swapping speaker wiring, as Roel suggested, could allow you to eliminate (or verify) that cause.

Although I don't have a schematic for the 8000 to help confirm this, the fact that the headphones work on both channels makes it highly unlikely that much is wrong. Unless there are speaker fuses in-circuit after the headphone jack, a blown fuse isn't a cause to consider.

Best of luck.

Edit: Chony,I just saw your response to Gary, which you posted while I was writing the above. If you have a means of posting photos of the headphone jack "wiring" (soldering to the board, etc.), I could probably tell you which to try jumping. If you don't care about headphone jack speaker switching operation, that could be made permanent. However, since you referred to the jack as being "welded" in place (I'm sure you meant "soldered" ), perhaps you could have a friend help with this.

--Barry


[This message has been edited by quietDIN (edited 07-18-2005).]
Posted by: travlin'easy

Re: Speaker on keyboard not working. What could it be? - 07/18/05 09:56 AM

I'll try to scan and post the schematic diagram to this part later today. It's a small board with very few components. The jack is soldered to the board and has 7 connections. I would not recommend replacing the board, especially at the rediculous price of $100. The cost of the components and the board to Yamaha were probably less than $5 at the most--what a rip-off.

Gary
Posted by: Roel

Re: Speaker on keyboard not working. What could it be? - 07/18/05 10:51 AM

Chony,
Sometimes one of the amplifiers just 'dies'(one channel) or in case the L & R amps have a fuse of 'their own' one of fuses can be blown.

Perhaps I missed it, but does your headphone sound OK on both sides ? This is important to know.
If the headphone sounds OK : Please try to switch speakers first before starting other actions !


[This message has been edited by Roel (edited 07-18-2005).]
Posted by: travlin'easy

Re: Speaker on keyboard not working. What could it be? - 07/19/05 11:04 AM

Sorry I didn't get to this last night, but here's the board you were talking about--nothing complex, and not worth $100.



Gary

[This message has been edited by travlin'easy (edited 07-19-2005).]
Posted by: chony

Re: Speaker on keyboard not working. What could it be? - 07/19/05 11:21 AM

Thanks Gary -- this is actually not the board on the 8000. The 8000 also has a mic input!

Although, the socket does look the same as on the 8000. There are 7 soldered connections. Which one do I have to jump -- and how do I jump it?

(Btw when I disengaged the whole board, I got no sound at all.)

Thanks again, Chony.

[This message has been edited by chony (edited 07-19-2005).]
Posted by: Fran Carango

Re: Speaker on keyboard not working. What could it be? - 07/19/05 12:08 PM

Pull out the speakers and call it a 9000 PRO!!!
Posted by: travlin'easy

Re: Speaker on keyboard not working. What could it be? - 07/19/05 04:06 PM

Chony,

I don't have the schematic for the 9000. This board is for the 3000, but the connections at the plug are very similar. However, you can determine which connections to jump if you have an OHM Meter. Without the board, the signal cannot get to the speakers or the headphone.

Sorry I cannot be of more help,

Gary

------------------
Travlin' Easy
Posted by: PaulD

Re: Speaker on keyboard not working. What could it be? - 07/19/05 04:55 PM

First Question: Is the keyboard in warranty? If so Yamaha would fix it for free.

If it isn't, and you are unfamilar with electronics, find a local electronic repair shop, they should only charge you about 60.00 for the 5-10 mins it will take them to fix a 1-3 dollar part (replacing it).



------------------
Paul Davis
Generalmusic
Generalmusic.US
Posted by: chony

Re: Speaker on keyboard not working. What could it be? - 07/19/05 06:12 PM

I WOULD LIKE TO THANK EVERYBODY FOR ALL THEIR ADVICE AND HELP! YOU ALL WENT OUT OF YOUR WAYS, AND THAT'S WHAT I LOVE ABOUT THE SYNTHZONE COMMUNITY - ITS ALL ABOUT GIVING!!!

THANK YOU! Chony.

In the end though, it seems that I'll just have to take this to a local fixer!
Posted by: quietDIN

Re: Speaker on keyboard not working. What could it be? - 07/20/05 12:06 AM

Quote:
Originally posted by travlin'easy:
Sorry I didn't get to this last night, but here's the board you were talking about--nothing complex, and not worth $100.

Just as a point of interest, since Chony is going to have the 8000 professionally repaired -- the headphone circuit Gary posted shows use of only 5 of the 7 available jack connections. Three of them are for the headphones (left, right, common ground). Two more are likely used to mute the speakers (I assume the 3000 shuts them off when phones are plugged in, as is usual), but the jack apparently isn't doing the work directly (otherwise the unused two jack switch contacts would be connected). It appears therefore that any actual speaker switching is done elsewhere, perhaps by a relay or other device(s), and the jack just switches that circuit.

That's why, since I don't have a schematic, I asked for a picture of the 8000's actual headphone wiring. If the 8000's circuit is like the 3000's, the speaker problem may not at all be related to the headphone jack.
In fact, some keyboards have a separate amp to drive phones, and if that's the case the speaker amp could be out on one channel and the phones would still work on both.

Enough conjecture; Chony, when you get this fixed, would you let us know what the actual problem was? BTW, if you're in upstate NY (not NYC), I might be able to take a look, if you'd like.

--Barry
Posted by: Bernie9

Re: Speaker on keyboard not working. What could it be? - 07/20/05 03:47 AM

Just as a point of interest,my KN7000 lost the right main speaker. My earphones work in stereo. My repairman told me I could have inserted a wrong plug to mute the speakers,and shorted out one side of the amp. He is a factory authorized technician.
Bernie
Posted by: John_CA

Re: Speaker on keyboard not working. What could it be? - 07/20/05 01:31 PM

Barry,

According to the schematics of the 3000, the headphone jack (which does have it's own Op Amp and Power Amp circuit - 0.65W 2ch) silences the speakers by triggering a Mute circuit. Each channel has a transistor switching, detected then by a "Decrease Voltage Detection Circuit" They don't use any relay. Also the Outputs (Fixed and Variable) have their own Op Amps.

------------------
Have a nice day smile
Posted by: quietDIN

Re: Speaker on keyboard not working. What could it be? - 07/20/05 02:48 PM

Quote:
Originally posted by John_CA:
According to the schematics of the 3000, the headphone jack (which does have it's own Op Amp and Power Amp circuit - 0.65W 2ch) silences the speakers by triggering a Mute circuit. Each channel has a transistor switching, detected then by a "Decrease Voltage Detection Circuit"

Thanks for that information, John. It looks like my conjecture (based only on seeing the pc board layout Gary provided) was correct.
It was obvious that only one of the jack's switching contact sets was being used, and that to mute both channels additional circuitry would be needed.
Quote:
They don't use any relay. Also the Outputs (Fixed and Variable) have their own Op Amps.

Not having the schematic, that's why I said "relay or other device(s)"; FETs are often used in this application (due to their low "on" resistance), although bipolar transistors can do the trick as well. If the PSR-8000 has a similar arrangement, a failure of a transistor in the mute circuit is another possible cause of the loss of output to one channel's speakers in Chony's unit.

So, does anyone have similar info about the PSR-8000?

--Barry
Posted by: loungelyzard

Re: Speaker on keyboard not working. What could it be? - 07/20/05 04:29 PM

Hey Gar: You got E Mail......Pose
Posted by: loungelyzard

Re: Speaker on keyboard not working. What could it be? - 07/20/05 04:51 PM

I checked trouble shootin in the shop manual on the psr9000, which may be about the same,as the 8k only thing I could find that's not been suggested is a plug left in the aux send (right)on the back, will block the sound on the right?? probably not it! But check out that jack (possible stereo phono plug could have damaged it or somehow so's its not grounding out.)

I'm not very knowledgeable on solid state
electronics, but years of trouble shooting on electrical and mechanical devices taught me to look first at what the history of the device is ie whats the last thing done to it, or what was going on at the time. Seems This board has been apart a couple of times recently if my memory is correct and if I've got the story straight. Seems like there was something unplugged or something, My thoughts are remove the back and take a good look at all the plugs, and move every wire to see if a ground or something may have been missed in reconnecting....Just a thought, usually something very minor. (that 8000 is built like a sherman tank) Hope you find it........Cheers....Pose
Posted by: quietDIN

Re: Speaker on keyboard not working. What could it be? - 07/20/05 05:36 PM

Quote:
Originally posted by loungelyzard:
I checked trouble shootin in the shop manual on the psr9000, which may be about the same,as the 8k only thing I could find that's not been suggested is a plug left in the aux send (right)on the back, will block the sound on the right?? probably not it! But check out that jack (possible stereo phono plug could have damaged it or somehow so's its not grounding out.)


Thanks for checking; it would be nice if Chony's problem turned out to have that simple a cause. Unfortunately, according to the PSR-8000 Owner's Manual, a disconnect at the loop send jack would result in no output at headphones and aux-out, in addition to speakers. Since Chony said the phones and aux were working, I assume that can't be the problem.

--Barry