Question about RF-7 II : Distance from the wall

[derrickdj1]

The wall is a gain control in a way.  The closer to the wall, XO the speaker a little higher.

[Pete H]

it's all about playing and listening when you have the time and when you add or subtract from the room you will alter the sound.  I added a soffit over the entertainment area and it affected the bass out of the 7's a ton and required me to play with all the placement and settings again. 

[jvanhambelgium]

Mine are pretty "free standing" to say : more then 1meter from any wall (I think 1.5meter from backwall, and 1.3m sidewalls or something)

Toe-in is also pretty heavy : I've used to position them at 45° so my ears would be directly "on-axis" with the Tractrix, but lately I increased toe-in even more so the "cross" in front of me (slightly)

 

On top of that Audyssey Pro (based on a XT32 Onkyo receiver) takes care of further room-correction/DSP and subwoofers integration. Running dual SVS PB13 Ultra's that plays always, even in 2-channel sources.

[Chris A]

So that now they are closer but still they are 50 cm...Another question is: Your RF-7 speakers fire straight to the listener or they are parallel to the walls (or... something in the middle)?

 

These speaker location issues with ports located on the rear always leave me a wondering why Klipsch (Indianapolis) would design for rear ports since they create so many issues, it seems.  Additionally, Klipsch (PWK) noted the advantage of placing loudspeakers in corners, and he wrote a JAES article on that subject in the 1960s using a prototype Cornwall (which, if you haven't looked at them, has front ports) to illustrate the advantages of corner loading.  I agree with trying them out within 18 inches of the corners or walls.

 

The toe-in question comes up a lot.  If you're running stereo only, I'd actually recommend toeing them in to intersect their centerlines in front of your listening position by a metre or so.  The advantage of doing this will stabilize the stereo image as you move from left-right out of the exact center sweet spot.  But you must get the various acoustic reflectors between the speakers (equipment racks, electronics boxes, free-standing flat screen TV, etc.) at least a metre away from each midrange RF-7 II horn mouth--otherwise you'll have early reflection issues from between the speakers.  I always recommend placing carpet on the floor (if you don't already have it) just in front of the speakers, and use acoustic absorption material on the side walls and front wall between the speakers, if they are located in room corners.  This will increase imaging performance.

 

If you listen with the speakers toed-in to aim directly at your listening position, you will likely experience the 1.8 kHz notch in the frequency response due to HRTF issues with stereo-only (i.e., you need a dummy head with microphones in the ear locations to measure the FR dip). 

 

Aiming the speakers to intersect their centerline behind your listening position will usually put more energy on the side walls if the side walls are within 1 metre of the speakers.

 

If you are using the surround system all the time without 2.0 or 2.1 stereo, then you have more freedom in toe-in angles because the center channel negates the HRTF issues of stereo. 

 

Chris

Edited November 7, 2015 by Chris A

[LeoeL]

Carpet is on the floor.

Not yet absorption material on the side walls (it's still a work in progress room...). Only a heavy mattress :-) on the left corner (waiting for bass traps) due to room shape.

I just moved the intersection behind me and I lost a lot a bass. Now I need Audissey calibration again.
For the time being, ​ I'm happy because the "flaccid" sound of drums disappeared!  :-)

Edited November 7, 2015 by LeoeL

[Chris A]

Sounds like you're on your way to a solution that works for you.

 

Chris

[WMcD]

In my view, placement and toe-in are a matter of the room.

 

On bass.  I have Forte II in a business office with a square floor plan.  They are diagonally right in the corners with just an inch between the back corners of the boxes and walls.  They are not boomy at all, at least on my favorite classical station WFMT (Chicago) the greatest classical station on the planet.  Smile.

 

They don't sound boomy on rock stations either, but you can hear the processed quality of the program very clearly.

 

It seemed to me that the arrangement in the office should lead to radical alteration of bass. But then I realized that the suspended acoustic tile ceiling is probably transparent to bass.  On the other side of it, above, the space opens up to a vast expanse of volume (area) with the concrete floor of the suite above being two feet above the nominal ceiling.  It could be almost anechoic for bass. 

 

That might not be your situation at home, but the whole analysis of Eigen values (bass reinforcement) seems to assume a room with hard walls with no doors, pass throughs, or adjacent rooms.  And that does not happen in real life.   You have to experiment with your room.  

 

On treble and toe in (and this could be affected by how far you're away from a room corner).  In my view, it Is not just a matter of what you're aiming toward but also what you're aiming away from.  The 45 degree aiming in theory keeps the sound off the front and side walls.  but I think if you have most reflection from the front or, alternatively, from the side, you might well get a reduction in reflection from the problem wall by adjusting toe in. 

 

The bottom line is that there is no "one size fits all" solution because everyone's room is different. 

 

WMcD

Edited November 7, 2015 by William F. Gil McDermott

[WMcD]

I've told this story before but it bears repeating.

 

From what I understand, architechs back in the 16th century or so would build a scale model of concert halls being planned to see how the model sounded. I'll guess they might use a 1:16 model and given the enoumous size of the final hall, the model would be the size of large modern living room, probably. There are tales of poor results when this was not done as a preliminary study in modern days.

 

So. I have a tub area with sliding glass doors. I have a Sony Tap Tune in there and listen to NPR in the morning. (No remarks please.) Went the sliding glass doors are closed the audio is very reverberant, as you'd expect.  Like yelling in the boy's room in high school.

 

The surpizing thing is the effect of sliding one door open about 10 inches. It seems to me this creates about five percent of area without reflections. The effects of reverberation totally disappear.

 

So this is my scale model of a living room.

 

If you have a portable radio (or something like a modern table radio) you should experiment with placement around your home. I think you'll be enlightend about the changes in rooms and placement.

 

WMcD

Edited November 7, 2015 by William F. Gil McDermott