CLX set-up / Toe-in (or out).

[rower30]

I've had my CLX Art's for about two years, and am still amazed at how good they are at everything except mid bass punch. That feeling as I am coming off of Dyn Audio C4 Signatures that have a LOT of mid bass PUNCH. The stereo Balanced Force 212 subs I've added go a long way to covering up that deficiency. As good as this combination is overall, I really have no regrets at all. EVERYTHING else is substantially better that the C4's except that one small item. Detail and voice texture is to die for and hey, I'm one of those weird people who LIKED the Thiel CS3.7's for their detail texture. I always felt that was an underrated speaker, and a sub or two would fix the low-end just fine.

Well, maybe there IS another spot the CLX are problematic; set-up. The 30 degree Curve Linear Line source makes CLX set-up a pain, but well rewarded when you get it right. The Dynamic driver type speaker I could set-up in a flash by aiming the line from the mid / tweeter panel such that the virtual intersection of the two panels "beams" hit just behind my head in the typical seating position. And, the C4's were more of a spray and pray dispersion speaker with a nice big sweet spot. Not a bad thing, really.

The CLX on the other hand, need some care in set-up. You can't really tell WHERE the "mid / tweeter" panel is aimed by visuals, and the 1/3 to the inside panel flashlight rule still leaves a LOT of room for adjustment. My perception is that from my seating position, I could move my head forward or back and hear a differing tonal balance. Same left to right. If I sat back, life was good but I did have a "head in a vise" image position. To me this seemed less than optimized.

I turned the subs OFF to concentrate on what impact the image the most and is more directional. Then I started to move the INSIDE tweeter edge FORWARD into the room (less toe-in) 1/2 inch at time and listened to a LP side in entirety so my brain could just adapt to the new sound verses placebo effect claiming a difference, which was still possible. When I had moved the panel inside edges 2.5" forward, all of a sudden I could move my head forward or back into the chair and side to side with nary a change in tonal balance. The image got much tighter, although smaller it is plenty lifelike BIG, still. I'm pretty happy with the change, and the image sound stage seems wider, too. I can close my eyes and point to the side images and they fall outside the edge of the panel spaced 8 feet apart (no more room to go wider, and I have then six feet from the rear wall). Extended listening also allowed me to remove a +0.5 dB left speaker balance adjust as one sits by a wall, the left out in the open. This centered the image. The new set-up removes the small adjustment. The CLX really, really are sensitive to the image placement in front of you.

My guess is that this new 2.5" change places the virtual intersection of the two panels to image BEHIND your head so that you are JUST inside the triangular intersection verses having it near in front of you (where I started). The in front virtual intersection made your head "behind" the sweet sot, and moved it INTO the sweet spot when you leaned forward or sat upright. I don't want to get too far into the triangular intersection as the image then gets diffuse and thin. Planer speakers also lose SPL the closer you get to the panel. If the volume stick wide open, run TOWARD the speaker and AWAY from a dynamic driver speaker.

So my question to you all is, do you set-up your CLX, SUMMITs ETC to exhibit the same seated image? The exact toe-in or out isn't important as the room will alter that some, but the end point may well be the same, get a good stable image in a wider sweet spot for best enjoyment. I'm going to add a soft panel BEHIND each speaker on the wall and see if the image tightens up some. The CLX is still a single seat speaker for the magic to happen so I haven't done anything magic there.

I seem to be getting great results with an Pass Labs XP-30 driving a MOON W-8. I'm not experiencing any downs side to the tonal balance and get a very wide variation in source material indicating that the CLX and down stream electronics are passing the voice of the recording well. Tubes aren't necessary with CLX. Yes, the W-8 is "warm" sounding at a dead start, and takes several songs to clear it's throat but hey, the CLX are good enough to let you even hear this!

So I LOVE this speaker for FOLK music and even some rock at times. It is unforgiving on giving you a homogenized sound like the C4's did (warm stuff up and move the overall sonic pallet to a middle ground) but once you realize it is playing it as it is much more so, the magic of nice sources reaches levels most speakers can only stab at, and it does it with no sense of trying. Wonderful.

Best,
rower30

 

[Tosh]

As long as you have ANY asymmetry wrt to both speakers, room centerline, and first reflection surfaces, you'll be chasing your tail. Get out your tape measure and make them symmetrical for position, rake, and toe. When the room geometry (and large furniture) allows perfect symmetry, the sweetpot is no bigger than a golfball, but that's a good sign...

 

[rower30]

Rooms, being what they are, measuring symmetry is likely to be getting you more wrong than right all things considered. My room is "L" shaped and the furniture in few rooms is identical along each wall or even rear wall. So measurement any surface is a "general" start.

The CLX won't go all British on you and drop a band on the head of a pin, that's a given, but a firmer sweet spot does sound better. Imagine a DOT that seeming BIGGER but is fuzzier around the edges to get there. You can tighten the focus some and then go too far in the opposite direction and get the fuzziness all over again. Every speaker has a "right sized" image based on directionality.

My CLX do NOT like a lot of toe-in, that's for sure and even 2.5" movement makes a noticeable change. Sometimes marking the floor with tape and trying things yields unexpected results. We seem biased to what we have set in place the LONGEST, as though that really means anything most of the time. For me it meant "pretty good" for an initial set-up. Better was 2.5" farther away!

The sound of the CLX was at first distracting as the detail seemed overwhelming compared to dynamic drivers. Now, It's a right as rain and I wonder what I was thinking other than familiarity bias. For those of us who don't like change WE can be our stereo's worst enemy.

 

[Tosh]

Rooms, being what they are, measuring symmetry is likely to be getting you more wrong than right all things considered.

Please tell me more!

 

[RCHeliGuy]

FWIW I have an asymmetrical room.

I downloaded a free copy of RoomEQ, purchased a Calibration microphone and a USB preamp.

Then with my computer connected by asynchronous USB to my OPPO 105D I let it do frequency sweeps to show me the response of my room.

There was lots of comb filtering, but it was surprising how much the frequency response changed with small changes to the speaker position ( it's distance from the front wall, how much I toed them in and how wide they were apart.

I got it have an overall fairly decent response of about +/- 5dB with some smoothing.

My next step is to put some sound deading directly behind my speakers. While my FR looks reasonably good when it is a bit smoothed, it still bounces around quite a bit without any smoothing.

The bottom line is that I still have quite a bit of comb filtering and absorbing a lot of the rear firing wave should dramatically help with this.

That said, I don't want a "dead" room either, so if the FR looks better but the music doesn't sound as good I'll pull the sound deadening down. I'm hoping that these changes will improve things all around.

 

[rower30]

View attachment CLX Data.pdf

Attached (I think) are the BF212 graphs in the "L" shaped basement. I need to experiment with soft backing behind the CLX to see if this helps sharpen the image, too. I'm out from the rear walls pretty good (~63"). But one thing is for sure di-pole speakers are set-up sensitive but well worth it for the amazing and real sound where it counts, the mid bass on up. My mind doesn't relate to bass as much as I don't get "practice" hearing it as much as the rest of the range. You hear mid bass on up all day long. Really deep bass is more fantasy stuff.

As far as room symmetry goes, the room LOADING is what determines where two speakers sound the same, not a measurement from some point to a reference. "Stuff" in the room and open sides ETC make this so. Still, the upper frequency arrival times will restrict optimized bass placement on speakers like the SUMMIT. You can't move them TOO much different as the higher frequencies are more directional which helps the speaker cope with irregular rooms (thank God!). Still, 2" can make a BIG difference on higher frequencies. The two BF212 subs can be moved some and allow the upper frequencies to be lined up better in the room.

I still find it hard to get the "best" bass, so I keep it turned down some near FLAT as I like a leaner crisp sound over sudden death rattles on many CD's. Why do they do this, anyway? It isn't even natural. The deep bass is SO, SO variable you find yourself tuning to a source and then the next CD or record makes you start all over. I just look at the min I like and the max, and then set it in the middle of the two and move on.

I should get my XP-25 soon and this is supposed to be a nice unit with CLX. Good bass too (good grief, here we go again!).

 

[Tosh]

The 'stereo' effect happens in the top end, not on the bottom end. It's OK if you like chasing your tail, but you are deliberately confusing your ears by not having perfect symmetry.

I have perfect symmetry, and the stereo effect is so strong it feels like I'm in a forcefield (recording permitting). But I adjust the bass balance a lot too, so we have that in common....

 

[RonR]

Dear Tosh,

What are the dimensions of your listening room?

Do you have perfect symmetry from a rectangular room with parallel walls, or as a result of careful room treatment?

 

[Tosh]

Nice rectangle: 13'4" wide, 15'6" to 24'0" deep with ceiling sloping from 8'8" to 9'6" at peak. It's a 50's thin tract house lossy living room. No treatments except I have deliberately set up the speakers plus the modular couch and smaller furnishings to be as symmetrical as close as I can measure.

 

[rower30]

The 'stereo' effect happens in the top end, not on the bottom end. It's OK if you like chasing your tail, but you are deliberately confusing your ears by not having perfect symmetry.

I have perfect symmetry, and the stereo effect is so strong it feels like I'm in a forcefield (recording permitting). But I adjust the bass balance a lot too, so we have that in common....

Di-pole speakers are much harder to set-up with rear wall radiation as strong as the frontal SPL and assuming measured symmetry matches wave reflection time is the stuff of "ideal" rooms only. So I'm not so sure my tail is any easier caught than yours will be in real rooms. Matching the arrival time of direct upper frequencies is the trick, but it isn't as easy as measured symmetry. The room is not doing anything to deliberately confuse you, it is what it is. Now YOU can pretend your room is "ideal" and sit there with that assumption when a few speaker movements may show much improvement and of course the stereo image is set by higher frequencies. True, some rooms will achieve the best sound with measured symmetry, but no all, and certainly not most L-shaped rooms. We still adjust to what we want to see, not hear.

Most rooms sound best with diffracted sound verses absorbed sound, too. Trying to remove the room with absorbers often leads to a dead lifeless room over diffraction. Starting with a super clean "ideal" room and having to add absorbers to remove slap echo and such is often WORSE than a more normal room with random diffraction items (shelves, chairs, CD racks ETC) laying about. Always try diffraction first, and limit absorption in small doses.