My PX-5S doesn't turn on with batteries?

[TLc]

Hello. This thread possibly involves two separate issues.

 

There's some noise coming out of the phone outputs of my PX-5S, one that is there at a constant volume regardless of what volume is the PX-5S set to output. I think I read about this somewhere, but I couldn't find that exact issue being cited when I searched for it at the moment. Anyway, it's not super-strong, but it's quite audible and you notice it as soon as the keyboard is turned on. I don't know whether that's regarded as "normal", and as the output volume doesn't affect the noise level, I thought perhaps it's some ground noise from the AC adapter. So, I tried running the PX-5S on 8 Duracell AA batteries – it doesn't turn on! Why is that? I've put them in correctly. Is there a chance something's wrong with the wiring that should go from the battery compartment?

 

Thanks in advance.

[Brad Saucier]

Is anything other than the main power and headphones connected to the PX-5S?  Like USB? ..Audio in?  ..Line in?

 

For batteries...are they fresh new batteries? 

[TLc]

4 hours ago, BradMZ said:

Is anything other than the main power and headphones connected to the PX-5S?  Like USB? ..Audio in?  ..Line in?

 

For batteries...are they fresh new batteries? 

Nope. Only the headphones. I use an 1/8" to 1/4" adapter for that as I'm using an in-ear earphone by Shure, but I don't think should that induce noise, the connector looks pretty good. But I now tried something else - I have some old bass amplifier–really not the best option, but it should work–I tried connecting the Line Out (mono) of the PX-5S to it and let it do the amplification, and you can hear some humming added to the amplifier's speakers when just connecting the AC adapter (before even turning on the keyboard).

 

Regarding the batteries – yes, they were all new. I've unwrapped them just for this test.

 

EDIT: OK, I tried connecting it to my Babyface Pro. The input levels displayed by the BF seemed rather close to me–using the same gain settings the BF showed -6dB from the Line Output and -3.5dB from the phones output–the volume sounded similar enough in this situation (which is weird, I'd expected the phones output to become much louder/clip far easier, but perhaps that's the difference needed to drive enough volume in a headphone), but the timbre was different (even after adjusting the BF's input gain) – I assume it could be from the PX-5S's own amplifier coloring the phones output? Anyway, there's still some noise. It's weaker, though it's also different in character – instead of a hiss like the phones output gives, the Line Out sounds more like a buzz. The thing is, again, you can hear noise as long as the PX-5S is connected to the AC power (on or off). Only when I disconnect it from the wall power is the noise gone.

 

Another thing I noticed through my testing: there seems to be some sound leaking to the Line In of the PX-5S. I've accidentally connected my cable there first and noticed some sound. Again, I'm not sure how "expected" that is, and I wonder whether that could result in some "self echoing" if the internal signal somehow becomes fed to the Line In and then back from there into the output stage. It's really weak, so connecting headphones there doesn't reveal it.

[Brad Saucier]

Hmm.  None of this is normal for a PX-5S. Headphones should be totally silent.  The PX-5S has very low self noise.  Since USB is not connected, that rules out usb ground loop.  Since no audio input is connected, that rules out the audio in.  Check system settings, sound generator, external volume. Make sure it's turned down to completely rule that out.   Batteries should be working as well. 

[TLc]

9 hours ago, BradMZ said:

Hmm.  None of this is normal for a PX-5S. Headphones should be totally silent.  The PX-5S has very low self noise.  Since USB is not connected, that rules out usb ground loop.  Since no audio input is connected, that rules out the audio in.  Check system settings, sound generator, external volume. Make sure it's turned down to completely rule that out.   Batteries should be working as well. 

Well, the "External Volume" was set to 100, but changing it to 0 didn't silence the noise nor the slight crosstalk to the Line In. The crosstalk is quite low and would be recognized only if amplified enough, so I assume people might not detect it if they happen to try connect the Line In to a speaker by mistake. If you could check it with your PX-5S, connecting the Line In to an amp just to see if you can detect at least some sound leak, I'd know whether it's a defect with my specific unit or not.

 

I think the noise from the phones output could be a bit less audible when going through my Babyface Pro rather than directly into my headphones, but as I said, it's still there. The recording I'm about to post won't demonstrate it all that well as I used Touch Off at 100 so the relative volume of the noise is lower than usual.

 

So, the recording: I'm now more concerned with the timbre difference - it's actually quite huge between the phones and Line Out. I played a simple series of notes at a constant velocity of 100, each note first recorded from the Line Out and then from the Phones output. I tried to match the gain on the Babyface Pro, but as the signal seems to come out inconsistently differently between the two outputs, different notes seem to have different volume differences so it isn't even consistently matching.

 

http://picosong.com/Dg34/

 

Regarding the batteries, don't ask me why as I've checked last time to see they're all placed in correctly, but right now before posting this reply I tried again and suddenly the keyboard did turn up using the battery power. But, it didn't seem to affect the Phones noise.

 

EDIT: And here's a demonstration of what the signal leak in the Line In sounds like using the same gain as in the Line Out recording:

http://picosong.com/DgRR/

It was recorded from the L/Mono input. The R input seems to experience a bit stronger of a signal leak (because it's closer physically to the Line Outs? I don't know).

[Brad Saucier]

I can't detect any major timbre differences in the sample you recorded.  I do notice it's mono, not stereo.  If anything, summing to mono sounds slightly different for each output method. Or one is not summing at all?  

 

And yes, very low level line out crosstalk is present on my unit.  I never noticed it until I amplified it as you did.  Never had a reason to amplify the line input before today.  

[TLc]

1 hour ago, BradMZ said:

I can't detect any major timbre differences in the sample you recorded.  I do notice it's mono, not stereo.  If anything, summing to mono sounds slightly different for each output method. Or one is not summing at all?  

 

And yes, very low level line out crosstalk is present on my unit.  I never noticed it until I amplified it as you did.  Never had a reason to amplify the line input before today.  

I'd say the difference in that demonstration is quite noticeable, but now when you mention it, the Phones output is stereo, and I connected the Line Out from the L/Mono. I can see the L/Mono outputs a mono mix-down of the two channels if the R Line Out has nothing connected to it, which is what I recorded. Now, the Phones outputs in stereo, and I connected it with a mono 1/4" cable. In this case it doesn't happen at the software-level, but I assume the cable still causes the two signals to be mixed into mono, and I'd say the timbre of the Phones output on my recording sounds similar to how it is through ny earphones.

[Brad Saucier]

Left/mono out sums both left and right channels into one mono when the right is not connected. The right out only gives you the right channel.  Keep in mind the concert grand piano tone is a stereo sound. Notes in the bass end will have more presence in the left channel while the right has more upper octave presence.  

[TLc]

3 minutes ago, BradMZ said:

Left/mono out sums both left and right channels into one mono when the right is not connected. The right out only gives you the right channel.  Keep in mind the concert grand piano tone is a stereo sound. Notes in the bass end will have more presence in the right channel while the left has more upper octave presence.  

I had some further insight after posting it and edited my comment, so it could help if you'll read my comment now (but shouldn't the bass be more prominent on the left side and vice versa? Or are the reflections inside the piano supposed to reverse these?).

[Brad Saucier]

Oops. Yes. Left for bass.  Got my words mixed up as usual.  Corrected. 

 

Using a mono tip/sleeve plug in the stereo headphone jack will give you one channel. The other will be shorted out on the ground sleeve.  

[TLc]

14 minutes ago, BradMZ said:

Oops. Yes. Left for bass.  Got my words mixed up as usual.  Corrected. 

 

Using a mono tip/sleeve plug in the stereo headphone jack will give you one channel.  The other will be shorted out on the ground sleeve.  

Are you sure? As I mentioned, the recorded output sounds pretty similar in timbre to how it is right into my earphones (other than being mono). The one that sounds different overall is the Line output.

 

But, as the volume difference between the outputs is different depending on the note, I assume it could be related to the cable and mono/stereo signal. I guess I'll need to get a stereo cable for the Phones output and record both of these as stereo to really compare.

 

Still no answer regarding the noise, though. As the volume knob doesn't change the noise level (I assume it only changes the volume digitally inside the sound generator), it seems like it involves the internal amplifier which is consistently engaged through the Phones output. It is definitely not totally silent, so I don't believe there could even be a difference in interpretation here.