I was working on sealing the speakers into the Pyra. Sealing them?

Yes, sealing them! The speakers we're using are special speakers that have some of the best sound you can get when they're assembled properly. For that, they have some special tricks. The back volume (part of the case) has to be sealed, otherwise, the membrane permanently moves to its limit which makes it sound totally overdriven.

I've sealed the speakers with self-cut padding. Of course, in the end, this will be cut by a machine and we only have to apply it.

First, we need some padding on inside the case so that the membrane has enough space to fully move. The speaker will go onto there and more padding (to seal it) will be added to the support bars of the case.

Then the PCB goes on top of it, like a sandwich.

The result can be seen here:

[MEDIA=youtube]BZcFnunrVGw[/MEDIA]

This video shows a comparison between the Pandora, the GPD XD and the padded Pyra. All of these have been recorded with the same microphones. The volume of the recording has NOT been changed, so you can hear the volume differences here.

With the reduced back volume, the Pyra is already louder at 75% audio than the Pandora is with full volume... and sounds a lot better as well.

However, sometimes it already sounds a bit overdriven - most likely an effect of the reduced back volume or maybe the sealing is not 100% yet. There are also some other tricks I want to use to improve the quality (it sometimes sounds like we have a resonance frequency as well).

The GPD XD has more bass right now (ours will improve when I don't cover the back volume with the sealing), but it sounds like it has some weird reverb combined with a resonance frequency. Looking into the GPD XD, it seems to use the full case as back volume... which explains that.

Some music tracks sound better with the GPD XD, some sound better with the Pyra... but that's only the first test, I hope I'll be able to improve audio a lot :)

Well, that's it for today. Just some short sound-related news, but I guess it makes some of you happy :)

BTW: Playing C64 commando at 100% volume plays fine without overdrive... but it was too loud for the microphones, so I couldn't even record it properly. It was REALLY loud!

You can discuss about that and see pictures here: https://pyra-handheld.com/boards/threads/parts-boards-and-the-rotator.77687/