Axiom Home Page Forums General Discussion The Water Cooler Pro logic 2

I've always been a 2 channel guy when it comes to music-maybe even a snob when it comes to DSP modes and multi-ch music. I've always written off DSPs (hall,stadium,concert...blah,blah,blah) as just hokey gimmicks to impress the uninitiated and I still feel that way. But...

After reading Alan Lofft's article on PL 2, I gave it a try just for grins. Guess what?....I like it very much.

2 channel in old pro logic sounded like crap but PL2 sounds great with terrific imaging and spaciousness. IMO, there is just enough material in the surrounds to convey space but not so much that it is distracting (like much of what I've heard from multi-channel SACD/DVD-Audio where it is not uncommon to hear musicians coming from the surrounds)-no drum licks or trumpet players etc. coming from behind/along side me, thank you very much.

But for the fact that it puts ambience material in the surrounds, the front speakers (in PL 2 mode) sound much the same as in 2 channel mode meaning that I don't feel like I've lost any of the magic of the music.

I haven't measured db level but I notice that in PL 2 mode there seems to be a slight increase in db level (perhaps due to the matrixed material from the surrounds). It also seems to make older not-so-well recorded music more tolerable somehow (psychoacoustic perhaps?). Thanks to Alan for shining the light on PL 2 for me, I'm having fun with it.

Any thoughts/comments on Dolby PL 2?

I actually like DTS Neo:6 better. Normally I just listen in stereo, but it's kind of fun to use the surround modes. It also shows off just how good the QS4s are (as long as they're crossed high enough!)

Note: how well PLII works varies widely with source material. With favorable source material PLII can construct very impressive surround sound. With non-favorable source material, it's flat and lifeless.

Here's a Dolby Labs document listing recommended demo material for PLII:

http://www.dolby.com/assets/pdf/tech_library/39_PLIIDemo.pdf

Mike, I've also cited Alan's two articles on DPLII in the past when contentions of stereo being more "natural" were raised. Actually his "Stereo's Intrinsic Flaw" article discusses the basis in a little more detail, especially the "Big Two-Channel Flaw" section. Sure, those "Jazz Club", "Beer Garden", "Sportin' House", etc. DSP modes add artificial reverb and may or may not be pleasing to a listener, but DPLII, Logic 7, etc. add nothing artificial and simply extract the natural ambience from the stereo channels and steer them to the side or back where they belong. It often isn't realized that the majority of sound at a live performance doesn't reach the listeners from the front as direct sound, but as reflected sounds from the walls. This article illustrates in fig. 10.4.1 that the "critical distance" where the reflected sound exceeds the direct sound can be around 4 feet in a typical listening room and even in a large concert hall is only about 20 feet.

As Joe points out, the effectiveness of the ambience steering varies from disc to disc; this appears to depend on how much ambience was mixed into the stereo channels from the front microphones or ambience mikes further back in the hall(if used). An extremely close-up recording with less ambience may be relatively flat, although DPLII's dimension control, which increases the level of the surround channels, can partially compensate for this.

Lots of good info JohnK but you don't say if you like it or not. Whadaya think?

In reply to:

---

As Joe points out, the effectiveness of the ambience steering varies from disc to disc

---

Yes, I found out today that PL 2 is not perfect with all discs. It steered the chorus on one particular recording to the surrounds. It gave me a good chuckle.

Wait till you try Pro Logic IIx

Mike, I guess it wasn't explicit, but on the classical CDs which I have the ambience content is generally enough to make the listening experience a little closer to reality when DPLII is applied and the parameters adjusted to suit. Incidentally, this reminds me of how Masa reported his delight with the effect.

Yeah but do you like it. J/K

I didn't know Masa was a PL 2 fan. I sure do miss that guy around here.

What's Denon "SRS TruSurround"?
Is that something similar to ProLogicII?

Never mind found this link:
SRSTruSurround

It's different; SRS creates a surround experience using just 2 speakers...

Jaime