My first impressions of the Pyra


Inqui

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AAhh, well, power supplies can indeed cause such effects.

What actually causes such "whining" is usually vibrating capacitors. If they hit the resonance frequency of the PCB, the PCB starts to vibrate which turns into the noise you can hear.

Power Supplies (especially cheaper ones) can cause different vibrations - which lead to that issue. It can basically happen with any device.
The first power supplies Craig sourced from China for the Pandora actually caused the touchscreen to stop working, as the power signal was VERY unclean.

Please try a different power supply and cable to see if that changes something!
Tried it now with complete different setup, still the same.
It's not loud enough to anoy me, so please see this as a single information.

Wouldnt it make sense to get a bugtracker ?
Maybe a section in forum, so that we dont spam normal threads with this.

Titel:
#0005-Issue:0001 (resolved) whining coils while charging

Or something else I faced (I hope its just my micro usb adapter. So would be nice to chat with something who is interested in this issue and maybe can check it there device.
#0005-Issue:0002 (open) micro-usb kills Pyra, till Bat is removed

;-)

Edit: charger are Sony 2,7A and Anker 2x2,5A and two different trustworthy cable.
 
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elw3

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Do you have other ways to get a whine?
Mine does a rather loud one when the keyboard brightness is set to max.
Also a less loud when the modem is powered.
 

Inqui

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Hmmmm, keyboard is turned off the whole time. I'll try later
 

elvissteinjr

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I've been getting audio volume fluctuations (usually quieter), presumably under load but not always. In those situations, holding any keyboard key would increase the volume a bit until letting it go as well.
Is that behavior known? I know software state for audio is pretty basic, but this isn't a hardware issue, is it?
 

EvilDragon

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I've been getting audio volume fluctuations (usually quieter), presumably under load but not always. In those situations, holding any keyboard key would increase the volume a bit until letting it go as well.
Is that behavior known? I know software state for audio is pretty basic, but this isn't a hardware issue, is it?
Hm, interesting. Please check the following:

1. Test if volume changes if you press on the case (not a key). The speakers use spring contacts - maybe they don't have a proper contact on your unit (which changes if you press on the case).

2. Open Alsamixer to see if the volume actually changes.
 

EvilDragon

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Oh. And I remember there's some low-power mode for the audio stream.
It can be enabled / disabled in Alsamixer as well (it's that hpll or similar controller, forgot the name).
Maybe that can cause such issues.

I'll also try on the units I have here.
 
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elw3

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Far fetched, but can it be the volume wheel? Even when untouched it sometimes flickers and changes on its own.
What are the mapping steps? If they are like 5% or something, and the wheel flickers around a border that sounds plausible.
 

EvilDragon

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Far fetched, but can it be the volume wheel? Even when untouched it sometimes flickers and changes on its own.
What are the mapping steps? If they are like 5% or something, and the wheel flickers around a border that sounds plausible.

Yes, that can be the issue. The volume daemon is very simple at the moment and needs optimization (deadzone, polling, handling ALSA / PulseAudio, etc.... I'll post more about that.
That's why I mentioned to open AlsaMixer. If the volume wheel is the issue, you will see the AlsaMixer slider moving :)
 

ClockworkCoder

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I may have missed this - there are so many posts on the Pyra now! I'm wondering what the responsiveness is for drawing using the stylus?

I'd like to think it would be handy for drawing quick ideas / sketches on the Pyra, but wonder how practical that might be in reality.
 

elvissteinjr

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Hm, interesting. Please check the following:

1. Test if volume changes if you press on the case (not a key). The speakers use spring contacts - maybe they don't have a proper contact on your unit (which changes if you press on the case).

2. Open Alsamixer to see if the volume actually changes.

I've not been able to reproduce it the same way as yesterday yet, but there has been similar behavior under load at least. Nothing keyboard related, moving windows around made it quieter (extra load from compositor if I had to guess). After a bit of messing around, the volume isn't really coming back either. Sometimes the right speaker is a good bit quieter than the left one for short bursts during this as well.
No visible changes in AlsaMixer, nothing for the balance either.
No changes from pressing around the case, though right now keyboard input doesn't affect anything either.

This is kinda weird and inconsistent, but doesn't look like it's hardware at least.
While this does appear to happen under load, it's not like the audio itself ever cuts off or stutters when it happens. Yeah, this is probably not that helpful after all, but something is up.
 

elw3

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I thought i imagined that the speakers have volume differences...
Guess not.
 

EvilDragon

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I've not been able to reproduce it the same way as yesterday yet, but there has been similar behavior under load at least. Nothing keyboard related, moving windows around made it quieter (extra load from compositor if I had to guess). After a bit of messing around, the volume isn't really coming back either. Sometimes the right speaker is a good bit quieter than the left one for short bursts during this as well.
No visible changes in AlsaMixer, nothing for the balance either.
No changes from pressing around the case, though right now keyboard input doesn't affect anything either.

This is kinda weird and inconsistent, but doesn't look like it's hardware at least.
While this does appear to happen under load, it's not like the audio itself ever cuts off or stutters when it happens. Yeah, this is probably not that helpful after all, but something is up.
This can be related to some weird audio mixing / channel mapping.
I already mentioned to aTc during the tester that it sounds as if the audio is coming from both speakers whenever I only play from the left one (as I'm sine waves for testing, this could've been my imagination and I've not further checked it yet).

We're not using the hardware audio mixing feature of the chip yet - so there's only one ALSA device with four channels. The first two are the headphones, the second two the speakers.
Who knows what ALSA makes of that... maybe it tries to do some 5.1 mixing with these four speakers and tries to create a virtual center?
 

FBnil

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Obligatory complain: The keyboard layout is terrible.
I agree, all hispanics are alienated due to the missing ñ

España - Spain
Es pana - "It's liver" (cooked) or "It's a breakdown" (broken down car)

It's not loud enough to annoy me, so please see this as a single information.
I'm one of those that can hear pretty well, and eventhough the Pandora audio cirquits were created by an audiophile, I could still hear the hiss (white noise) when the screen was active. So to listen to music I either had to disable the screen or use those big headphones that need lots of power and by increasing the volume, the signal/noise ratio was good enough to make the hiss inaudible.
... so it will bug me too.

The Pandora had a noise when the audio cirquits shut down, that one did not annoy me. To me, it was something that defined the Pandora (the hiss will stop after these three? succesive noises).
 
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Letalis Sonus

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Who knows what ALSA makes of that... maybe it tries to do some 5.1 mixing with these four speakers and tries to create a virtual center?
ALSA's default behavior is entirely based on mostly HW-specific configuration templates (/usr/share/alsa), which should always default to an unmodified stereo output. Stereo upmixing is something that one needs to configure manually, it is not an internal feature but requires making use of its channel mapping plugin in a certain way.

However, PulseAudio directly sends its mixed samples to the hardware channels, at this point it is impossible to modify these samples in any way through an ALSA configuration. PulseAudio itself does provide an optional stereo upmix feature, though.
 

Autian

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One may try to use JACK to test each channel individually, as demonstrated in the following example:
"desk out" is my PulseAudio sink and Hardware Capture/Playback speaks for itself.
jack.png

with plugin packs like Calf or LSP you can also do some complex audio processing stuff.

It is somewhat fiddly to set up overall, I never got it to run stable on my desktop PC (sometimes crashes out of the blue or freezes). I am using the cadence-claudia (for configuration and for loading plugins) and jack2 packages in Arch Linux. The cadence-claudia from the AUR has the routing application as seen here compared to the regular cadence package.
I don't know if this is helpful to you, hopefully I gave you some ideas here.
 

aTc

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The problem is that alsa/pulseaudio sees the channel mapping as :
Channel Map: front-left,front-center,front-right,rear-center
Instead of the 4.0 setup it should have by default (which would be front-left,front-right,rear-left,rear-right)
I tried forcing this in several places in the pulseaudio config, but i can't get it to pick it up properly, it's always left,center,....

Also weird is that "pactl list cards" returns no cards at all, which would normally be the place to set these things.

playing a 4 channel wav to the device directly works fine though, that doesn't try to do anything smart with the channel mappings, and you get each individual channel sent to each individual output.
 
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stevenc99

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If Audacity is working already on the Pyra that would be another good way to test audio.
Would be also interesting to play a sine wave from the left speaker at the same time as the *inverted* signal from the right speaker.
If both channels are played correctly, you would notice weird phase effects as you move/turn your head.
If the channels are being "mixed" then you would hear nothing at all.
 
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