Ht front/rear presence speaker

hi,
Can anyone enlighten me on the use of
presence speakers and what your using

Just home theater, or high resolution multi-channel audio too (e.g., SACD, DVD-Audio, DTS, etc.)

If the latter, you want all of the speakers to sound as similar as possible. Forget about a difuse rear presence. Any of these audio formats can and do pan instruments around the room and the same instrument will show up in different channels (including the bass guitar in the rear channel). When that instrument moves, you want it so the sound is the same, only from a different location.

For my front (height) and rear surrounds, I use 2425s on butt cheeks with a W10GTi woofers and crossovers that I designed/built to work with this combination.

That's great thanks for the information
brian

Toddalin is dead on! I have had 3 exceptional Home Theater systems - all used a JBL 4641 18" subwoofer.
All were/are 7.1 surround systems (but the same idea applies to 3.1 or 5.1 systems - match the speakers!)
First one - I had a set of DCM TF (Time Frame) speakers TF-100 for front mains, a TimePiece in the center, TF-700 for sides and TF-600 for rear surrounds.
Sold them off and built a system with Vandersteen 2CE fronts (VCC-1 Center), Vandersteen 2CI side surrounds, and the same DCM TF-600s in the rear.

Current system - I have 2 pairs (4) UREI 809A Coaxial speakers for Front mains and Side surrounds, and the same DCM TF-600s in the rear - with a DCM Timepiece in the center. (The UREIs are studio monitors built with JBL drivers)

Every time, the best thing is to have the exact same speaker across the fronts and in as many places as you can for the best tonal match - and a realistic, immersive sound field.

I agree 100% with Heather. The 3 front-channel speakers must be identical to create a seamless front soundstage. If you can't use surround speakers that are identical to the fronts, get ones that are as close as possible to the fronts in timbre.

I also use a 4641 for a home theater sub and it totally kicks butt! It's tuned to 25Hz, so with a HPF and a bit of EQ it'll put out some serious bass all the way down to that frequency.

I'm learning all pertinent info.

To build on what Toddalin has said, My front L C R currently 3 JBL AS 2225's, all surrounds/rears are JBL 8340a's (6) and heights/Atmos (4) are JBL 321 C's. All have JBL compression drivers on the top to help match timbre and it is quite amazing when they all come together like this. The balance between them is very smooth and movies and music really sound great with a level of clarity/definition that is very fun to listen to.:)

Even better... it was involving enough for me to forget about the speakers, etc... :)

(how it's supposed to work)