The Stereo Separation Issue

[lnx64]

I think we need to figure out what the issue is on the Wiz with stereo separation.

I have done a few tests, and took apart a Wiz to figure it out, and while I couldn't find the cause, this is what is happening.. The left channel isn't as loud as the right channel. The left channel ALSO plays the right channel sound. Right channel plays only right channel sound.

This is literally the only thing preventing me from using the Wiz over the Caanoo. I love the Wiz to death, nice and small, and has VSync support in PicoDrive and that makes games with raster effects look as good as they did on a CRT, coupled with the AMOLED screen. But this sound issue, because I am an audiophile, is highly disturbing and annoying.

I have tried many Wiz's and found this is the case on all of them. I can make a sound test mp3 for you guys to try it out, but a ROM of Sonic on the Genesis is a test of it's own.. When you get rings, they alternate between hard left and hard right. This is true on the Caanoo, but the Wiz it's hard left, mono, hard left, mono (with a subtle hint to right balancing for the right ring sounds, but still comes out on the left.).

So, anyone with a spare Wiz, lets get this issue resolved. I'm still tinkering with my spare Wiz and still can't find it, but did find that the left speaker WAS soldered to the WRONG pads. Still didn't fix it though. At the DAC itself, it plays fine, so it's not a driver or DAC issue..

 

[LTStone]

I think we need to figure out what the issue is on the Wiz with stereo separation.

I have done a few tests, and took apart a Wiz to figure it out, and while I couldn't find the cause, this is what is happening.. The left channel isn't as loud as the right channel. The left channel ALSO plays the right channel sound. Right channel plays only right channel sound.

This is literally the only thing preventing me from using the Wiz over the Caanoo. I love the Wiz to death, nice and small, and has VSync support in PicoDrive and that makes games with raster effects look as good as they did on a CRT, coupled with the AMOLED screen. But this sound issue, because I am an audiophile, is highly disturbing and annoying.

I have tried many Wiz's and found this is the case on all of them. I can make a sound test mp3 for you guys to try it out, but a ROM of Sonic on the Genesis is a test of it's own.. When you get rings, they alternate between hard left and hard right. This is true on the Caanoo, but the Wiz it's hard left, mono, hard left, mono (with a subtle hint to right balancing for the right ring sounds, but still comes out on the left.).

So, anyone with a spare Wiz, lets get this issue resolved. I'm still tinkering with my spare Wiz and still can't find it, but did find that the left speaker WAS soldered to the WRONG pads. Still didn't fix it though. At the DAC itself, it plays fine, so it's not a driver or DAC issue..

Is this a problem with just the speakers or also with earbuds too And does it have this problem with audio out through the usb connector or is that possible..?

I wonder if fixing the stereo is will make the Wiz louder ooh and is there a software way to increase earphone volume as I find it too quiet for my liking.

 

[lnx64]

It occurs on the speakers too, have not tested the line out through the EXT port, I don't have a cable that even uses it..

 

[Mr.TwisT]

Are you using Win2x?
Win2x has a sound problem

 

[darklight1138]

I do notice stereo separation isn't good at all through the speakers.

Seems much better through headphones.

Good luck, Inx64. You're good at starting the process for getting stuff fixed so let's hope this can get fixed as well!

 

[lnx64]

Are you using Win2x?
Win2x has a sound problem

Has nothing to do with Win2X. It is NOT a software problem.

Remember what I said in my original post, from the DAC itself, the problem is NOT occurring, which tells me somewhere on the motherboard the problem lies in the amping of the signal.

As for the speakers, the issue is the same as on the headphones, it just sounds worse from the speakers..

 

[jmetal88]

Honestly, I haven't noticed this yet on my Wiz. I guess it's because I don't use it to listen to music on it or anything, and the videos I watch tend to not have any stereo separation in the first place.

As for playing games, for me the speakers are too close together to tell any difference between them anyway.

 

[Reo]

I made two test MP3s, one that plays exclusively on the right channel and one exclusively on the left. Using these, I was able to confirm that this happens on my Wiz through both the speakers and the headphones.

Now I'm wondering if the Caanoo suffers from the same problem.

 

[lnx64]

I made two test MP3s, one that plays exclusively on the right channel and one exclusively on the left. Using these, I was able to confirm that this happens on my Wiz through both the speakers and the headphones.

Now I'm wondering if the Caanoo suffers from the same problem.

My Caanoo does not, and sounds beautiful, which is why I'm constantly going back and forth between the Caanoo and the Wiz.

 

[lnx64]

I have done a few more tests, and made a discovery on this.

It's backwards to what I was thinking.

Left channel is playing a perfectly mono sound, meaning both left and right sound on the left channel are of equal volume, and right channel plays only that that is meant for the right channel, and does not play the left channel sound.

What this sounds like, is the pre-amping circuitry is what is at fault here, doing both mono and right channel sound.. Sounds like whatever IC does this, is improperly wired..

I wonder, do the older GP2X's do this?

 

[jmetal88]

I have done a few more tests, and made a discovery on this.

It's backwards to what I was thinking.

Left channel is playing a perfectly mono sound, meaning both left and right sound on the left channel are of equal volume, and right channel plays only that that is meant for the right channel, and does not play the left channel sound.

What this sounds like, is the pre-amping circuitry is what is at fault here, doing both mono and right channel sound.. Sounds like whatever IC does this, is improperly wired..

I wonder, do the older GP2X's do this?

Hmm, I wonder if they do, too. I can't remember noticing anything on mine, but it's been very long time since I sold it, too.

I'm pretty sure my GP32 does proper stereo, but the GP32 has the problem where if you're trying to push too much through the system or graphics bus at the same time, the sound develops crackling.

 

[lnx64]

What?

The problem is with the Wiz.. NOT the speakers..

PS: You're a freakin spambot.

 

[jmetal88]

I just wanted to post that I have, indeed, confirmed the separation issue.

The left channel plays both the left and right channel sounds at equal volume. Therefore, the left channel is perfectly mono.

The right channel plays right channel sounds at a slightly louder volume than the left channel, and it also plays left channel sounds very, very quietly (it's very hard to notice that).

So, it seems the right channel operates (almost) properly, and the left channel plays sounds from both channels as if they were mono.

 

[lnx64]

I just wanted to post that I have, indeed, confirmed the separation issue.

The left channel plays both the left and right channel sounds at equal volume. Therefore, the left channel is perfectly mono.

The right channel plays right channel sounds at a slightly louder volume than the left channel, and it also plays left channel sounds very, very quietly (it's very hard to notice that).

So, it seems the right channel operates (almost) properly, and the left channel plays sounds from both channels as if they were mono.

The right channel, is actually within normal separation. Usually a channel will "bleed" some audio, because remember, these are unbalanced audio outputs..

But the left channel, forget it, that's a massive royal screwup.

 

[lnx64]

Still can't find the source of the problem. I am going to need a new oscilloscope, mine died. I was getting close, looks like a diode may be potentially incorrectly soldered.

 

[LTStone]

Still can't find the source of the problem. I am going to need a new oscilloscope, mine died. I was getting close, looks like a diode may be potentially incorrectly soldered.

Would that be an easy fix?

 

[jmetal88]

Still can't find the source of the problem. I am going to need a new oscilloscope, mine died. I was getting close, looks like a diode may be potentially incorrectly soldered.

That would make sense, it could be failing to prevent the sound from one channel entering the other.

Would that be an easy fix?

Depends on how good you are with a soldering iron, I guess. It could involve just flipping the diode around, or perhaps desoldering one end and running a jumper to somewhere else. Nothing too complicated, but it would be a very small part to work with. You'd probably want a fresh tip on your iron.

 

[LTStone]

Depends on how good you are with a soldering iron, I guess. It could involve just flipping the diode around, or perhaps desoldering one end and running a jumper to somewhere else. Nothing too complicated, but it would be a very small part to work with. You'd probably want a fresh tip on your iron.
[/quote]


I could probly do that..

 

[lnx64]

Yea, I need to figure this out. I don't want to mention any part locations until I am certain. I have a spare Wiz I am working with, one that has an amoled screen that's not terribly good at colors (no rot, just bad colors).

 

[LTStone]

Do you think this would make the Wiz louder or just increase quality or both?

Yea, I need to figure this out. I don't want to mention any part locations until I am certain. I have a spare Wiz I am working with, one that has an amoled screen that's not terribly good at colors (no rot, just bad colors).