Hi all, i've had this headset for several months now and i've also been pretty disappointed with the tinny rear speakers. I checked here (this thread actually) ages ago, did some tweaking and gave up as no matter what I did it was just the same with my SB Live! card. I play BF2 mostly and I just lived with it. Pfft.
Recently i've upgraded to X-Fi Extreme Music and hoped things would be sorted...not so, although I do have a sub channel working now due to proper 5.1 from the X-Fi
Today i've re-read this whole thread (!) and after much tinkering and invalidating of warranty have now concluded that it IS by design (a pretty daft, unrealistic one tbh considering a truck driving by behind you won't sound tinny with no low freqs).
Unplugging the front feed from the soundcard and putting it in the rear feed on the amp box confirms to me that it has to be the amp/headphones doing this. The rear feed from the soundcard into the front feed on the amp gives perfect sound to the front speakers.
So with that I assume for now the headset's fine and the smaller size speakers won't make 'that much' difference to the sound produced. Let's have a look in the amp box...
For a start it's heavy because there's a piece of iron in there, perched on two plastic standoffs. Also worth a mention is the real reason I opened it up - poor/no connection on the front output jack and the LED not working unless wiggled. The cause of these turns out to be the copper track coming away from the board where the pins solder to them, breaking the connection. Some lengths of bell wire soldered in and everything's aok again.
Ok, now i'm not an expert - far from it..ok I can use a soldering iron, I know what a resistor does and I know one end of a rectifier diode from the other but that's about it. So this bit may be totally wrong and hopefully an electronics engineer can confirm or deny what I think.
Following the tracks from the inputs eventually leads, via the rotary volume control to some resistors, one for each signal line, before it then passes to what I believe to be amp chips. There's only one transistor and this seems to feed all 3 chips. So, here's the value on each SMD resistor for the signal lines:
Centre: 183
Sub: 153
Front Right: 183
Front Left: 183
Rear Right: 3002 (looks like 3002 anyway)
Rear Left: 3002
Now, could it be that the signal to the rear speakers is a lot less than the fronts, therefore causing a tinny sound?? Looks suspicious to me, all of the components after the resitors appear to be the same for all lines. I'd really like to change the resistors but it's beyond me and i'd prolly blow the box up!
I really like the sound from the front channels and the sub gives good bass but i'm so disappointed with the rear sound. It's just not natural..as was said earlier if you turn your back on say a crowd then the sound will get slightly quiter but it definitiely won't lose all it's bass sound!!