Spy Hunter Sound Interference

[demogo]

Hopefully this is better:

http://youtu.be/ZFH5v9w30eI

The iphone doesn't really capture the depth of the sound it should. It may seem like normal interference, but It's pretty snowy during play. Of course this is nothing like a bad DAC where it's crazy loud and crappy, but it is annoying and not worth overlooking.

This is all a matter of degree of the hiss, I think.

I just powered my SH on and stuck my head up near a speaker and I can indeed hear a faint hiss so you could say that's normal.

When I stand in a normal driving position I can't hear the hiss.

When I play the game with my head right next to the speaker I can't hear the hiss at all when the music is playing. In this same position even w/o the music the game sounds mask out 90% of the hiss. You really have to be wanting to hear the hiss to even notice it.

When I stand in my normal driving position and play you can't hear a hiss whether the game is playing or not.

Is this the same for you?

 

[ManiN]

Same white noise but you hear it even several feet away even just walking in the room. Something's up. Midway would never release it like this.

 

[demogo]

Same white noise but you hear it even several feet away even just walking in the room. Something's up. Midway would never release it like this.

Nope, definitely not normal.

Do you have another linear power board you can swap in to see if that helps? If not, can you borrow one from someone?

 

[ManiN]

I'll ask around. Bout were I'm at to try and narrow this down more.

 

[ManiN]

Poking around last night, I noticed if I put a large cap between the speaker output and ground, about 75% of the white noise goes away. I tried this with the ground in the amp and got no change. The amp ground appears to be an isolated one for audio according to the schematic. Definitely a ground issue somewhere. I may try the cap filter method back on the cheap squeak, and if it works, I'm done with this. Wasted so much time on it.

 

[demogo]

Good luck. Make sure you update this thread when you solve the issue. You never know what future internet lurker will use this thread to solve their problem.

 

[ManiN]

So is the normal white noise where you hear it when you walk up to the machine to play but unless you are in the playing position, you likely don't really hear it? That's what the level is now with the cap filter. I kinda think I'm not going to be able to do much better.

 

[demogo]

So is the normal white noise where you hear it when you walk up to the machine to play but unless you are in the playing position, you likely don't really hear it? That's what the level is now with the cap filter. I kinda think I'm not going to be able to do much better.

I don't hear it when I'm in a normal playing position. I pretty much have to put my head under the speakers to hear it.

 

[ManiN]

Hmmm I guess it's a little louder than normal still then.

 

[demogo]

Depends on your perspective, too.

I'm 6'2" so my head is way up from the screen. If I were 5'6" it'd be a different story.

There is definitely some white noise it's just not really all that noticeable in real world conditions for me.

 

[demogo]

I wish you were closer as I could have come over with a spare set of everything and we could swap stuff in and isolate the problem in an hour, tops.

Sure makes it easier to debug these things with a spare set of everything.

 

[ManiN]

Played with some caps and put one from a speaker output to ground at the amp and that reduces the hiss a lot but not enough, then tried some across the speaker wires which does reduce it even more to an acceptable level, but I think it causes a 'short' of some kind and the amp starts getting real hot. So across the terminals is a no-go.

 

[ManiN]

Well... Seems I was using the wrong ground. If you use a frame ground, it works fine. Must have been a short using the ground on the lamp board next to it.

I did notice with my slight low hiss that is pretty much acceptable, I now have no pop associated with the van light anymore. Must have filtered it out.

 

[demogo]

Well... Seems I was using the wrong ground. If you use a frame ground, it works fine. Must have been a short using the ground on the lamp board next to it.

I did notice with my slight low hiss that is pretty much acceptable, I now have no pop associated with the van light anymore. Must have filtered it out.

There is a slight low hiss, yes. Sounds like you're there.

Pretty funny that you filtered out the small pop with the flashing van light -- that's normal.

Good job!

 

[LyonsArcade]

I had one that got worse depending on how many lights were on. Once all the lights were on you were really in trouble. Tried all kinds of stuff (rebuilt power supply, different power supply, new cap in power brick, etc.) and eventually just wired in a switcher for the 12v line and that fixed it. I think the way I did it was I just ran the lights off the switcher and left the audio running off the original power supply.

 

[priglmeier]

spy hunter sound

I have a spy hunter that I re-capped all the PCBs when I bought it.
The sound has been OK, but at times the music has a bit of hum etc.

I noticed recently that after re-capping the monitor, a wg4951, the sound is crystal clear now. Might be worth a try for some of you dealing with the same issues.