OS theater bar

[firefox319]

I am trying to build a long and thin LCR bar that will sit under a 65" tv. I am trying to replicate the look and feel of the recently announced klipsch heritage bar, built with the OS designs. Left and right are the TM; the center is the MMTMM configuration. I have changed the ports from round to 2.5"x0.5" slots. I've built a few subs and am quite an accomplished woodworker. My material will be 1/2" solid maple with box joints on the corners. The sides will be recessed into the top and bottom. I expect the rear baffle to be removable in all three sections. The bar will be paired with a yet-to-be-designed sub and OS TM surrounds. Please pardon my sketch-up inexperience... I didn't replicate the port or baffles on the right section.

I'm just looking for a sanity check on a design like this. I have scoured the web and have not found anything similar. Generally, this should work, right? I know these speakers were designed as stand-alone... will the front baffle extension materially change the sound quality? Is the port velocity on a 0.5" slot too much? I don't have the knowledge to model something this complex and just want to avoid disappointment if I am missing something.

Any words of wisdom would be much appreciated.

[Chris Roemer]

Bunch your drivers together (I say this at least 10 times each day). Best case would be to have the tweeters actually ABOVE the woofers (you could ALMOST do this easily w/the CC portion of the bar).

[spasticteapot]

Chris is correct.

If you can find room for three of the center-channel kits, that'd work just fine.

[davidroberts]

I am not aware of an OS MT or MTM that Paul designed for horizontal use.

I have played around with this a bit and I would recommend the OS center channel as basis for the design. I would leave the original design in place for the center but move the L/R speakers to a MTMWW Configuration with the 2.5 woofers toward the center.Moving the WW should cause little if any issue with the designed xover because they are lower in the frequency band.

My left/right speakers are Curt and Wayne's side firing Cinderella design and I am currently running a hybrid OS center channel as is with a modified woofer section (instead of a single 8" I am using two 6.5", two 4ohm versus the 8 ohm 8") from Curt's Cinderella speakers.

The best CC I have ever used was the WMTW design that I worked on with Dennis Murphy, CJD and Curt on but unfortunately it requires a considerable amount of real estate. Not really high on the WAF factor...Not to mention the original RS tweeter are no longer available so the crossovers would have to be resigned. Worst yet we had designed MT's, WMT's and WWMTM's for that series just to see a small tweeter change wreck the design. I had several hundreds of dollars just in shipping test enclosure to Dennis to develop the series...

If you have the room I would recommend three of the OS center channel kits in the configuration on MTMWW - WMTMW -WWMTM. Pair it properly with a nice sub and I would imagine you would be more than happy/

[beatle]

Subscribing. I would like to do a similar project and the OS platform looks like a great starting point. I have a couple of the original OS MT bookshelves that I really liked.

[firefox319]

Appreciate the feedback. The MMTMM has almost twice the volume as the TM version. So with all three channels with MMTMM, the box gets a bit chunkier. It certainly won't be as sleek but I think it's still within acceptable range. I do have a MMTMM kit purchased several years ago that I never got around to making but there are probably other designs that have smaller volume that would shrink the overall size.

The driver spacing is about the same as Paul's original MMTMM design, but the baffle is obviously taller. This does allow space to place the tweeter above the woofers as Chris suggests above. I have pictured it both ways in the drawing. Is it better to put the tweeter off the vertical axis or just stick to Paul's original design?

[Chris Roemer]

Personally, I like your orig. vers. (except w/the drivers closer) w/just TMs outboard (w/the tweeters on the outside). This will give you the widest separation (for stereo "effects"). I doubt you need the extra SPL of all those woofers. I'd go TMs on the outside, and MTM in the center (just for symmetry).

[firefox319]

Ok, hopefully last design tweak! Per your suggestion, I grouped all the woofers toward the center. I will stick with the MMTMM in the center since I already have all those components.

[davidroberts]

If you are wanting something that looks symmetrical I would just use the three OS Centers, There is no real benefit to using the MT on the ends and will likely require so adjustment to the xover. The displacement of the four BN3's is actually twice that of a single 4" (Sd*Xmax). Plus the levels are already matched being that you are using the same speaker across the sound bar.

With the design being a 2.5 way you should be able to re-orient the outside drivers to a MTMWW configuration without disrupting the original xover design any if at all. This will still push the boundaries out for the left and right channels while keeping the design symmetric and avoiding crossover modifications.

If you stick with the last design you posted you will definitely want to move the L/R woofers further out to the end of the bar and closer to the tweeters.

What is the max depth and width you are dealing with?

[Chris Roemer]

Sorry, but the LR woofers NEED to be very close to those outside tweeters (push 'em way out there). Tweeters on the outside help to give a wider stereo image.
Your CC section should all be pulled together (in the middle) w/everything as close as possible - preferably w/the tweeter above the woofers (like an upside-down "V"), wwTww.

[firefox319]

I sincerely appreciate your feedback and thoughts. Many years ago in school I studied electrical engineering in the classical sense. There was always a finite solution. Practical, real-world design, however, is a game of trade-offs with no discrete solution. It's easy to jump down the rabbit hole to try and correct for everything. Truth be told, this speaker will be mounted on a wall, between two windows, in a medium-sized room with a vaulted pine ceiling, and maple floors (with a rug). Oh and my design has a top/bottom that overhang the front baffle... It would be impossible to correct for all those variables!

David - the more I think about it, the 3 center configuration makes the enclosure just too large. I have 60"+/- to play with horizontally but I am much more sensitive to depth and height. Sticking with the MT for the L and R channels allows me to shink the OD of the box to 4.5" deep and 6.5" tall. Most TVs are 2-3" deep plus another inch or so for a wall-mount. I really like the idea of having the bar flush in depth with the TV. Gives a cleaner look. Make the enclosure too tall and the 3 or 4" drives look too small relative to the height. Since the center MMTMM has 2x the enclosure volume of the MT, using 3 of them in the bar would push the dimensions an extra inch in height and depth. it just gets chunkier and the goal with this project was to optimize first for form/aesthetics, then for sound quality.

I guess I am back to the first design with the components on each channel tightened up at either end and in the middle.

Once again, I really appreciate the insight!