Greetings,

I have a GameCube and a surround amplifier with lots and lots of inputs.
The amplifier can cope with DTS, Dolby 5.1 via PCM and/or optical in, but no Dolby Pro Logic II. So Dolby Pro Logic II sounds that come from my GameCube's two plugs are NOT converted to the 5.1 speakers, but only two (crappy stereo).

Is there a relatively cheap solution/converter that will convert a Dolby Pro Logic II signal to a digital Dolby 5.1 signal?

The creative decoder DDTS-100 sounds very nice, but is over 100 euro's and has lots of stuff i already can do on my current surround system.

Sounds like an issue with the way the surround is encoded in your gamecube. All Dolby surround types are essentially the same encoding. A DD 5:1 decoder is fully capable of decoding 3:1 or 2-channel PCM surround. If your receiver manual specifically states that it will not decode 2-channel analog inputs, then it's a rarity. The receiver should have some indicator on it's face that reports what surround mode it's in. If it indicates surround, then the problem is probably that the gamecube is not encoding surround. But even a plain stereo signal should still deliver some info to the center channel. The exception would be if the signal is actually 2-channel mono.

Plain stereo sound can be converted to 5.1 using Dolby Pro Logic II, about any reciever/amplifier can do that.
//Danne

Nothing gets "converted to 5:1". A Pro-Logic or DD decoder will create 3:1 from a normal stereo signal. Left, right and rear mono plus a center channel which is extracted from the difference between left and right.

Did you forget about the Music/Movie modes?
http://www.hometheaterhifi.com/volum...ix-3-2004.html
//Danne

Yeah, that's a great 2-year old article.
If you read the OP, you know that his receiver does not have P-L II, which many do not. The answer to the question asked is: no, a 2 channel analog audio cannot be "converted" for 5:1 discreet decoding. But it should still get decoded to surround by his receiver, as any stereo signal would.

AFAIK, Mr B, there's really no such thing as "Dolby Pro-Logic II encoding". ProLogic II is a decoding strategy only.

Solution: Get a better amp/reciever...
//Danne

True, with a slight difference. You have omitted the subwoofer, as the low sounds are "downmixed" as well. The decoding of stereo sound can be really impressive with a good amplifier. The problem is that to my experience GameCube has some serious shortcomings, when it comes to sound, even with a powerful amplifier. I have experimented with this issue some months ago.

Not a solution. The problem is the GameCube. The absense of P-L II in his reciever is not the problem. A new receiver will do nothing.

It'll handle PL II Music/Movie or some other type of upmixing matrix :P
//Danne

Indeed, Dolby Pro Logic II is a matrix surround technology and not a digital audio format.



I would require a matrix decoder that converts the stereo (plus pro logic stuff) to the 5.1 speakers. My surround set can't do that.

However, after playing Soul Calibur II last night i found out the surround set tries to output all the stuff to the speakers, but i'm not sure if that's just an equalizer or Virtual Dolby setting or a true matrix decoding. The display doesn't tell me if there's a signal decoding taking place. I think it's just a futile attempt of the surround set.


I guess i'm forced to get the Creative Decoder DDTS-100 if i want all the true formats.

Thanks for all your input guys.

Yes, actually it does. All DD decoders also decode matrix surround. Yours doesn't have P-L-II, but it does decode to regular surround (L-R-C-S). I still say the problem is the Cube, and better decoding equipment might be a disappointment for you. The only difference between what you have and a P-L-II decoder will be stereo surround channels vs mono surround. I really doubt you will hear any difference, unless your current receiver is really crap.

Well, it doesn't have PL II so... ;-)
//Danne

That would explain the surround system's current futile attempts.

Hmm, so there would be no real enhancement, because the cube's audio itself sucks.

Guess i have to learn to live with it.

That's my humble opinion. My receiver doesn't have P-L II, and it works great with stereo sources. Personally, I think P-L II is just more smoke and mirrors from Dolby. But, as you know Mr B, GIGO. Is it worth it to replace your receiver just to get P-L II? Probably not. I guess my test would be this: if you get great sound from DD inputs, then the receiver is not the problem.

What do you guys really have? Even the simpliest receivers from Yamaha (for instance) has it since years back.
//Danne

A Philips surround set (5.1 speakers of course) with SACD (6 in, amplify, 6 out) ,Dolby 5.1/DTS decoder, two PCM inputs, one optical in input and lots of stereo inputs.

When i bought it i didn't have a GameCube yet and was merely interested that it could cope with DTS (i love dvd movies with good sound). Back then there were only a couple of sets who could do that.

No way. It would mean to replace everything except speakers just to get a mere enhancement on my gamecube sound quality.

I see, oh well... stand alone recievers have it at least...
//Danne