MONODEER
Offline
the Netherlands

Hi!

How are you? This is going to be my first post here. I came across a little problem after getting my first backlight-kits installed. The problem is that some pules and waves and noises with tables have some kind of background noise after the modification. Not a hiss, but more like a low zoom. It stops when I add extra 'k' commands. The problem is that some clear pulses now seem to have a little ugly buzz. Maybe we did something wrong with the installation...

I am not really that technical so someone helped me out with this modification. Since you are probably going to ask how about the specific installation details, this is what we did:

- To get a better result, we installed something to make to contrast higher that got the pixels more sharp.
- The backlightkit wasn't installed directly to the battery but to the pins below the screen. 
- it was installed in a prosound modded DMG-01-CPU-6


Now, I played the exact same song on another prosound modded DMG-01-CPU-6 without the backlight kit and the sound seems to be better. It also has a little background buzz when playing some notes but way less than the one with the backlight kits. Also the bass of the one without the BL-Kit seems a little more clean and I got the feeling it just sounds better. (I don't know if this is possible) What's also weird, is that when I plug it on my adapter, now every sound get a major buzz. This buzz can also be stopped with the 'k' command so it isn't just overal background noise. This I really don't understand.

Also, the intensity of the backlight-kit also seemes to vary while playing a song. So, I think my DMG has a little bit of a problem that the backlight kit leeches from the circuitboard and not directly from the battery. Is that it?


- Can someone explain/help me out what to do to get the best and clear sound back?
- It this a common problem you get while installing those backlight-kits?
- Is it the DMG model?




Thank you so much in advance.

Mark

nickmaynard
Offline
rochester, ny

i wouldnt have thought that backlighting the gameboy would affect the sound. but what do i know? did you try the pro sound out before you did the backlight?

Kris k
Offline
BK

My backlit game boys don't really have any difference in sound from the non-backlit ones. It may be that thing you installed to sharpen the pixels (biversion i assume?) that has that effect on the sound. I don't know for sure, since I've never done that modification. Good luck figuring it out, let us know if you can isolate the issue.

MONODEER
Offline
the Netherlands

@ Nickmaynard: Yes, the prosound mod was fine before  installed the BL-kit.

MONODEER
Offline
the Netherlands

@ Kris: Yes, that extra mod we did was called biversion. I couldn't remember the word anymore. That will probably affect the sound. I think it has become all to heavy. Can this be solved to connect the BL-kit anyway else?

Since I'm not really that technical, I can't solve this problem by myself. Going to take some time.

Other question: Does the intensity of your backlit screen also vary by intensity while starting a song. Mine becomes less strong while starting a song. When stopping it, the intensity gets brighter again. So, that has to mean It all got a little bit too heavy to process I think...

pixls
Offline
Philly, PA, USA
MONODEER wrote:

Other question: Does the intensity of your backlit screen also vary by intensity while starting a song. Mine becomes less strong while starting a song. When stopping it, the intensity gets brighter again. So, that has to mean It all got a little bit too heavy to process I think...

Fairly certain that's about power draw and processing and stuff, if it starts to get really dim when playing a song you should change your batteries.

Timbob
Offline

Oh dear, I broke Monodeer's gameboys...

to the fix!

MONODEER
Offline
the Netherlands

FIXED!

After some testing, we came across the fact that it was definately the biversion that caused the buzzy sound!
So, we (read: Timbob) removed the chip, then restored the circuit and fixed me up with two fresh modded DMG's.

Two days later I took them to Blip Australia and put them to the master test!

chartedlife
Offline

Does anyone know if this is the case for all biversions? I planned on doing one but I don't want to if it causes an audible buzz...

MONODEER
Offline
the Netherlands

I don't really know the technical inside specificics nor do I have the technical knowledge of how to make the biversion work.

When I posted about this problem, nobody really seems to know what was the deal, so I hope you can make it work if you really want to do it. I have to admit that the biversion made the screen look sharpen than without it, but I don't think it is really worth it the risk of having shitty buzz at the end of it all.
If you don't want to risk the hassle, I would go for a normal backlight kit.

chartedlife
Offline

I went ahead and bought an inverted backlight and the hex inverter, so I might as well try it out and see, as far as you know you are able to repair the traces on the PCB right?

Edit: I was scared for a second that I actually necro'ed this post but I realized you had posted before hand

Last edited by chartedlife (Feb 27, 2012 1:55 pm)

MONODEER
Offline
the Netherlands

Yes you are! At least, Timbob was able to do it for me wink He will probably add some more technical info after we put some new life into this post. So, if you are not in a hurry, more info from him will soon be here. Otherwise: Good luck!

chartedlife
Offline

Not in a hurry at all, I may have another day or so for shipping so I will keep checking this thread until then.

Timbob
Offline
MONODEER wrote:

Yes you are! At least, Timbob was able to do it for me wink He will probably add some more technical info after we put some new life into this post. So, if you are not in a hurry, more info from him will soon be here. Otherwise: Good luck!

Timbob
Offline

But in all seriousness. I don't have that much technical insight that i know what really caused the buzzing sound. I biverted my gameboys as well, but I never noticed it before.. (Then again, I'm not as anal about my sound as Monodeer tongue )
I couldn't tell you if it happens with all biversions, or just the version of chip that I used. It looks like the chip somehow interferes with the sound of the gameboy, but I've got no clue as to how. It's one of those things that shouldn't happen, but still does.

If you're going to use your gameboy just for LSDJ, you can easily just get an inverted backlight and then use an inverted colourscheme in LSDJ, works the same as biversion, without the hassle of soldering hex inverters etc.

Glad i could be of little help tongue

Wilba
Offline
Melbourne, AU

Maybe the buzzing came from the four unused inverters in the hex inverter not being grounded. It's always a good idea to ground unused inputs to stop them floating and then oscillating between logic high and low. Or maybe it's EMI from using long wires to/from the hex inverter. Just a theory :-)

I didn't notice any buzz when I installed a dual inverter in my DMG: http://chipmusic.org/forums/topic/6031/ … -mount-ic/   Perhaps it's because there are no unused inputs or long wires.

But you're right, LSDJ users don't really need it... it's only good for using your DMG for something else (like game carts).