A new surround TM - completing the HT

[---k---]

They sort of stole the show (except for maybe my Open Range & Blue Man Group demos):



In this positioning (which wasn't perfect), they are not necessarily perfect sounding, but shockingly good. The sound changes considerably for the worse when we pulled them further out into the room, because we were taking away the ceiling plane.

Where you see them is where we listened to them. Everyone was impressed. The highs seemed a little rolled off. The base was extremely strong (Stronger than my Khans), maybe a little too strong and a little boxy. I'm sure clubbers would love them. They imaged well. The sound just seemed to float in the air above them. Moving around the room, the sound was very consistent. I got a good giggle out of standing directly over them in the null and having the sound just go away.

[cjd]

I think I'm going to tweak the crossover some more to clean up the bass end a bit - can get a little more sensitivity back. I think I missed a step somewhere in estimating where the bass response would be relative to everything else.

[villastrangiato]

I know this is off topic, but Mackintire's avatar is the absolute funniest thing I've seen in ages!!! :rofl:

Btw, I whole-heartedly agree with CJD's earlier comments about using dipoles and bipoles in surround sound applications. To me, bouncing sound off walls has always seemed counterintuitive to the main objective - render the recorded musical event in a typically hostile acoustic environment as faithfully as possible. I suppose you can deduce from this strongly held opinion that I've never been a really big fan of Bose stuff. And IMHO, for those interested in the charms of electrostats - without a solid understanding of the acoustics of your intended listening environment, buying a set of big, expensive, vibrating panels constitutes a major crapshoot.:conveyer:

[mackintire]

I know this is off topic, but Mackintire's avatar is the absolute funniest thing I've seen in ages!!! :rofl:

Old pic, I have a ton of those types of pics. Thanks tho....


Back to the review.


CJD I am watching this closely. I 'd be interested in knowing how they would integrate with Khan's (Seas tweeter variation). I 'm guessing very well.

[cjd]

Yes, the RS28A and Seas 27 series are similar in their voicing, though not identical - I need to determine if the silk dome RS28 is a drop-in for the metal, in which case I bet the voicing would be even closer to the 27TDFC.

[ibilisi]

I think I'm going to tweak the crossover some more to clean up the bass end a bit - can get a little more sensitivity back. I think I missed a step somewhere in estimating where the bass response would be relative to everything else.

CJD - Any updates on tweaks in the low end?

NoDestiny- Any updated listening impressions?

Still going to build these, just haven't "gotten the chance" yet (moving/winter).

[cjd]

No, I've not gotten back to them yet.

[victoon]

[

Mounted into the wall.



They seem to work quite well - subtle most times but they blend well with everything else - balance is quite good with me sitting quite a bit closer to one than the other. I watched most of the second half of The Return of the King - superb use of surround in this film.

The IB sub continues to elicit grins that make my face ache. It's just there, and then it's gone - no overhang, no ringing in the room.

wow, is that full birch plywood? looks gorgeous!

[cjd]

Yup, plain birch.

[Brian Bunge]

Chris,

How do you think these would sound as surrounds sitting on the floor? Kind of on either side or behind a sofa?

[---k---]

Brian,
Based on listening to them on the floor at my place, I think they could work well. Is there really any difference between the floor or the ceiling??? -I don't know- Our brains are used to hearing the surrounds sound above us. So maybe the imaging might be a little off. Could also be issues if the line of sight to your ear is blocked by furniture. I guess it depends on how picky you want to be.

I've wondered in the past if small surrounds like these could be hung using a two or three 3M commander strips each.

But, the real reason I'm responding is: Do you really want these when there is a version using the Anarchy driver? :twisted:

[BeerParty]

Chris,

I just realized, you didn't name these speakers! How am I going to start a build thread for these when you haven't given them a name?!? :P

[Brian Bunge]

Ryan,

This is more of a general question since I recently finished a new pair of towers and center channel. I was wondering if something similar using the drivers I have (DA175's and some sort of soft dome tweeter) would work for me in a similar alignment.

[cjd]

I think there are a lot of driver combos that work as long as the tweeter can cross comfortably quite low.

[mackintire]

CJD....are you leaving us hanging? Where's the BOM and final X-over?

[dwk]

Interesting - I completely missed this thread the first time through. I've been running through potential designs for placement in the upper corners of a room, and these are the closest completed projects I've seen. There will probably be excessive bass gain when moving from wall to corner though (particularly considering that they already seem bass-heavy), and they're probably too big for my application in their current form. Still, I may have to think about this, and I'd be interested in a tweaked xover.
Of course, if Brandon would ever finish his BBV2 design, adapting the MTM version to something like this might work even better, and would be smaller.

[mackintire]

CJD likes to tweak his designs and listen to them over the months before calling a project completed.

:?? He's probably still deciding if it cuts the mustard yet.....kinda like the the Ansonica's basically done, but not final until he calls it done.

Probably why his designs are so well regarded. ;x(

[Solid7]

2 Questions:

1) Would there be any issues to hanging these from the ceiling on drop rods? (think ceiling fans)

2) Is the shape/surface area of the mounting surfaces critical? (think custom enclosures - i.e., rounded sides)

Thank you!

[jagman]

I would expect that the lower mid frequencies and below would sound a bit thin if hung from the ceiling as the speakers were designed to be against the wall or ceiling. They are also a sealed design so they naturally don't go very low. Having said that I love the idea . Lets see what CJD says...

[cjd]

The most important things:

1. The tweeter and the mid-woofer baffle shapes, sizes, and relationship (45 degree angle, and spacing relative to each-other) stay the same (baffle length above the tweeter, below the mid-woofer could go longer, but not really wider, and the relationship across the 45 angle is somewhat critical here)

2. You don't listen directly on-axis with the tweeter.

You will lose a bit of low end support putting these away from surfaces, but that's not necessarily a critical point for surrounds. I cross mine at 70Hz, and they sound quite full when we listened to them placed on the floor (tweeter firing up), so they have some wiggle room.

C

[Solid7]

The most important things:

2. You don't listen directly on-axis with the tweeter.

Being that I am no expert, how far "off-axis" must one be? Or is "off-axis" an absolute? (as in, varying degrees don't matter) I can put this off-axis, but I'm just wondering if there is an optimal placement within this parameter.

Would you mind if I posted a room pic? I'd like some more specific advice.

Thank you.

[cjd]

I posted measured response from 0 degrees (tweeter axis) to 45 (or was it 60) off-axis, toward the mid-woofer. I should add, this off-axis is still on the plane moving toward being on-axis with the mid-woofer. Off-axis to the side has its own set of oddities.

On-axis has a definite null. 15 degrees still has remnants of the null but nothing bad. Beyond that it has pretty flat response.

It is pretty difficult to avoid odd lumps in the response (including nulls) if you're not mounting speakers at ear-level firing straight at your listener - so you're going to get inconsistencies and imperfections no matter what you do, so finding the best balance is really what I tried to accomplish here. That, and enable somewhat balanced sound where one listener was almost directly under a side-surround on one side, and a couch-width away from the other.

[Solid7]

Sounds like our goals may be similar. In a traditional setting, who doesn't have a couch and loveseat in the "L" shaped arrangement? But even more so, I have an open wall on one side, and an offset corner behind me. (think of a fat "L" shape, or a box in one corner)

This little setup seems like the best compromise solution that I have seen so far. When I get a chance, I'm going to post a picture of the room in question.

Thanks for your advice so far.

[Rbrockman]

Just found this thread as I'm contemplating a set of new surrounds.

These look like they would visually integrate into the room better than a standard TM in a square box.

current BOM is approx $140 per speaker which is very cost effective as well.

Would need to find a way to attach some fabric grills to these. May paint boxes to match wall color.

Any other listening / build reports?

[Endodoc]

Hi CJD
Many thanks for all the hours and obvious effort you put into these projects.
We neophytes are truly grateful.
I'm now preparing to build these and hope you can help with a few more bits of info.
What is a final weight? I have an open plan HT with suspended ceiling (no viable walls to fix to) so I either have to build a back board-slab-concrete to surface mount or through mount directly onto the slab (150 mm behind) which then varies cabinet depth on the through side ...
Have you refined the Xover yet or is it still as last posted 2yrs ago?
Tks for the help

[cjd]

I've been quite happy with the crossover. No changes.

No idea on weight but not too bad. 15-20 lbs?

[---k---]

No idea on weight but not too bad. 15-20 lbs?

I bet they don't even weigh that much. My little ones hanging on the wall are like 8 lbs (not the same design), hung on a wire from a picture hook.

[Zach_J]

But, the real reason I'm responding is: Do you really want these when there is a version using the Anarchy driver? :twisted:

Is there a link to this? I searched but couldn't find it.
-Zach

[---k---]

I think it is something CJD talked about, but I'm not sure if he ever had time to bring it to life.

[snmhanson]

Here is the Anarchy Marsala (tucked into the Ansonica thread):

https://www.htguide.com/forum/showthread.php?t=35601&page=2&pp=35

A few posts down from the top of the page. It's not clear if the design was built and tested, but it does offer the crossover design. I am in the process of building the RSS180-4 version of the Marsala, as I am hoping it will be a better fit with my Statement front stage.

Matt

[JoeAngelicchio]

Has anyone tried these with an Atmos capable receiver?

[Thoth]

Getting started again, looking at a BOM for these speakers.

Hi everyone. Just coming back to the forums after a sudden and unacceptably long absence, hoping to pick up again with some of the projects y'all helped me plan a few years back. I'm wanting to start with something small, and had always planned to build these for my surrounds.

Anyway, I've searched for a BOM and and never could find one (probably just missed it somewhere), so I whipped up this one and would appreciate a reality check:



Thanks in advance for the help. Good to be back!

[TEK]

Welcome back :smootch:
arty:

(sorry, no idea about the bom)

[Thoth]

Glad to be here! Hope to actually build some stuff this time around. Look forward to making some progress, a few mistakes, having fun, and learning a lot.