Do I need Pro Logic IIx?


I have a 5.1 system and am upgrading my Marantz SR7000 to separate components. I've already picked up an amplifier and am looking around for a second hand processor. Systems with Pro Logic IIx are newer and second hand units harder to find and more expensive than those with Pro Logic II. From what I've read, Pro Logic II supports five speakers and Pro Logic IIx supports seven speakers. As my speaker set-up is 5.1 and I'm not interested in 7.1, would I be losing anything if I pass on the Pro Logic IIx and go with Pro Logic II?
raduray
I realize we each have our own preferences and priorities. I've also noticed Audiogon is very 2 channel focused, while sites like AVS Forum have more interest in multichannel listening, independent of whether that is a movie or music.

For those interested, below is a posting from sdurani at www.avsforum.com, which I think provides a very good explanation of 7.1 versus 5.1. This also correlates very closely with my own listening experiences of 5.1 compared to 7.1:

"7.1 set-ups have a few noticeable advantages in the surround field over 5.1 layouts: more precise directionality (4 hard points vs only 2), better envelopment (4 speakers can literally 'surround' you better than 2 speakers ever could), and greater imaging stability (no matter where you sit, sounds at your sides and sounds from behind you stay locked at those locations because there are speakers there).

It is difficult, if not impossible, to get all that from only 2 surround speakers. Doesn't matter how good they are, one pair of surrounds can't be in two places at once (at your sides and behind you simultaneously). The best and easiest way to get stable rear-vs-side imaging in the surround field is to simply place a pair of surrounds at your sides and another pair spread out behind you. Of course, this assumes you can tell when sounds are coming from your sides vs coming from behind you. If you can't, then stick to a 5.1 set-up.

To deal with a couple of myths in this thread:

Room size or space is not a determining factor for 7.1 layouts. What's more important is seating location. If you're in a large room but your seating is against the back wall, then you're a poor candidate for a 7.1 set-up (no room behind you for the rear speakers). But if you're in a small room and your couch is away from the back wall, then you could probably do a nice 7.1 set-up (where surround-back information really sounds like it's coming from behind you).

Consumer level 7.1 surround processors have been around for almost 20 years, pre-dating 5.1 soundtracks by a solid 8 years. People using those processors haven't been waiting 2 decades for material that takes advantage of the extra speakers. They've been using all 7 speakers since day one. ANY source, no matter how many channels, can take advantage of a 7.1-speaker layout. Surround information contains sounds that will image at your left side, at your right side, and behind you. By sending these specific sounds to their respective speakers (which is what PLIIx does) you get imaging stability, wrap-around envelopment and surround directionality that a 5.1 set-up cannot deliver.

Since you already have a 5.1 set-up, I would move the RS-3 surrounds directly to the sides of the primary listening spot. This will give you stable lateral imaging, which is also important when listening to music in surround. For the rear speakers, I would get a pair of RB-3 bookshelf speakers (which match the sound of your other speakers) and spread them out at least 60 degrees apart on the back wall. The separation will provide you better envelopment and allow you to hear the rears in stereo (sound over your left shoulder vs sound over your right shoulder).

Use the attached 7.1 placement diagram as a starting point for your layout."

Note- the attachment referenced above was the Dolby recommendation for 7.1 speaker placement from their web site.

Thanks
Bruce
Thanks for all the responses. Great discussion. What do you all think about a Rotel 1068 for future 7.1 upgradeability. I do like to listen to multi-speaker music and ProLogic II is a strong preference. I would like to keep it to less than $1500 - second hand is OK.

Radu
Hello Again,

We will agree to disagree, plus I don't feel like typing 30 pages and boring everyone including myself.

I am chiming in again to say that the Rotel is pretty good, the 1068 sounds as good if not better than the 1098. I still think Arcam is a little better and Classe allot better. It is not price related either because the Classe is much better than Lexicon, Theta, Krell, and Levinson which are many times the price.

Thanks,
Duane
Duane - Bore us...Please bore us. Being the system designer to the stars, please enlighten us DIYers.

Bruce only provided the very basics of surround setup, be it 5.1 or 7.1. He hasn't even touched the calibration of the system, which would further establish the fact that 7.1 can outperform 5.1.

Duane - Since you've complete many systems for famous people, can you walk us through your calibration process for these systems?
Hello Again,

After calculating room nodes and finding out how many people will be in the room most often and correcting construction material issues, (mismatched density issues in walls and ceilings), I find out listening levels and habits.

I then match a speaker to the room based on the rooms ability to present frequency extremes and sustained pressure level taking into account the speakers dispersion and the performance limitations it will have in relation to placement.

When I find a speaker that has the right balance of trade offs, I determine the speaker’s character and weaknesses and I choose electronics that will boost up the weaknesses while leaving the strengths alone making the overall performance well balanced.

Examples:

B & W speakers need solid state amps that have a lot of decay in the bass but are clean, have tube like highs above 8 KHz. and have a fast and foreword midrange. (BAT, Symphonic Line, Electrocompenet, Classe, to name a few.) Bad matches would be Krell, Levinson, Bryston, and Conrad Johnson.

After that is chosen, if there are any characteristics that the client loves the most, (Bass power, 3 dimensionality, airy or sparkle), I fine tune that part with the pre-pro and cables.

For set up I place the right speaker against the wall firing into the room and move the left speaker into the room a 1/4" at a time until a bass note in the music I am playing sounds an octave deeper. At that point the speaker is working with the room instead of against it. There will be 3 or 4 points in the room that this will happen and I choose the one that has the best midrange as well or I compromise based on how much room it eats up or if it will be in the way. I then move my head up and down and find the sweet spot with in the speaker and if it is lower than the listening position I add rake to the speaker until it is tonally balanced and smooth without any sizzle or hollow sound.

After I find that spot I move the right speaker into the room until I no longer hear a bass note on one side lead the other in time.

After this is done I do the same thing to the center channel just playing stereo music into the left speaker that will no longer move and the right channel going into the center speaker. I move the center speaker until it locks in. Then I go around the room going between the left front and the left rear, then the right front with the right rear. The rears I move up, down, left, and right with in a range and find where it locks in.

I then integrate the sub or subs by movement, phase, rake, and toe in.

Now are you bored? LOL

This process of speaker setup takes about 5 hours.

Thanks,
Duane