A somewhat technical question to setup of center channel (HTM2D)

[JimTW]

We're building a custom wood center console for the Plasma TV and other
A/V components. The center channel speaker, the HTM2D, will go into a
cubby hole right underneath the Plasma TV. So, this means, the top,
bottom, left and right, and back of the HTM2D will be wood and closed off
with no air flow.

The idea is kinda like this picture posted by Chelseaforever, but wider and
shaped like the height and width of the HTM2D.


Questions...

1. Should I spike it?
2. How much space do I leave on the top, bottom, sides, and back?
3. Do I need to use foam to pad all the wood on the top, bottom, sides,
and back?
4. If need foam padding, how much space should I leave between the foam
padding and the speaker?
5. Will placing the HTM2D in the cubby hole going to affect the quality
of the sound?

Thanks!!!

[Kal Rubinson]

5. Definitely and for the worse.

Kal

[JimTW]

5. Definitely and for the worse.

Kal

But how do I mitigate around it since it HAS to be in a cubby hole?
Help! Tks.

[ShadowZA]

If it has to be in a cubby hole, it means that your sound quality will be compromised. I can't tell you by how much, though. An idea: Could you not have your plasma wall mounted and the HTM2D mounted on top of your wood centre console ... similar to what I have done here?



In this way your front end sound (left, right & centre channels) will tend towards being matched and there won't be any unnecessary resonance which will negatively affect the sound quality.

[DrJRapp]

Make sure that the HTM2 protrudes out from the cubby hole so that minimal diffraction is created with the tweeter and midrange.

[sikoniko]

youd need to insulate the cubby with sound absorption material (foam) to hope to have a positive outcome.

[misterdoggy]

I've got the htm2d on a shelf (look at my thread about speaker image just posted and yo will see a foto of the arrangement)

The htm2d is ported so you will really lose the use of the active ports in the back of the speaker. It is not made to be put in a cabinet.

[JimTW]

If it has to be in a cubby hole, it means that your sound quality will be compromised. I can't tell you by how much, though. An idea: Could you not have your plasma wall mounted and the HTM2D mounted on top of your wood centre console ... similar to what I have done here?



In this way your front end sound (left, right & centre channels) will tend towards being matched and there won't be any unnecessary resonance which will negatively affect the sound quality.

Ah yes, that is an idea, but it might bring the TV higher, which will be
a little high for our liking. We prefer it to be a little higher than eye level
when seated. I'll try to come up with other options with the speaker on
top... *pulling out hair*

[JimTW]

Make sure that the HTM2 protrudes out from the cubby hole so that minimal diffraction is created with the tweeter and midrange.

Good point, thanks!

[JimTW]

youd need to insulate the cubby with sound absorption material (foam) to hope to have a positive outcome.

Are you talking about the ones that have a wave like pattern to them?
Maybe 2 inches thick? Or are you talking about just any old regular
flat foam?

[JimTW]

I've got the htm2d on a shelf (look at my thread about speaker image just posted and yo will see a foto of the arrangement)

The htm2d is ported so you will really lose the use of the active ports in the back of the speaker. It is not made to be put in a cabinet.

How about if the back was open, and the sides a little bit wider than the
speaker itself, and place the speaker so it protrudes a little without the
top and sides of the cubby reaching forward enough to block any sound
going sideways?

[Kal Rubinson]

Frankly, you can try some of the suggestions such as open back, putting the speaker forward or, even, using foam but all of them are significant compromises. It's just a question of what sonic compromise you can tolerate for visual esthetics.

Kal

[audioqueso]

Regardless of technique, if you put it inside the cabinet, you will lose imaging. Just as a test, listen to your center close to solid objects, then place it on some sort of stand with a lot of space around it. The image becomes so much more spacious with a good amount of clearance. I did this test and was amazed at the difference.

[misterdoggy]

I like the idea of at least opening the back of the cabinet. I mean if nothing is obstructing the front and the back is open its better than closing it in completely.

Also having the Screen high on the wall or high enough so you tilt your head upwards just takes some getting used to. Its what I have. By being higher its above anything obstructing, easy to see at distance, because when the screen gets larger you want to get it back. Mine is 50 inches and you really need to get 5 meters to see well.

When you think about it, in the movie theater the Screen is "UP" :T

[D-bucket]

ShadowZA, I must say that your LCR speakers setup, especially with the grills on, accent and compliment your a/v cabinet stand & wall trim so beautifully. It is visually most stunning. And having the cc in the open nearly at the same height as your LR fronts with the carpet wall treatment behind them must also be sonically just as stunning.

JimTW, a cc speaker of such fine pedigree as the HTM2D deserves a little more elbow room than a totally enclosed "cubby hole". But I do understand if sonic bliss has to play second fiddle to visual appeal, at the very least consider leaving the back open if possible and move speaker forward on shelf to avoid early reflections.

[ShadowZA]

ShadowZA, I must say that your LCR speakers setup, especially with the grills on, accent and compliment your a/v cabinet stand & wall trim so beautifully. It is visually most stunning. And having the cc in the open nearly at the same height as your LR fronts with the carpet wall treatment behind them must also be sonically just as stunning.

Thanks D-bucket The wall trim (also in cherrywood) was done to assist in securing the wall carpet (against gravity causing sagging) and to prevent bubbles from forming over time. Always wanted to carpet the wall :twisted:

Sonically, I'm in 7th heaven at the moment. The speakers are broken in and the fairly thick pile carpet not only improves sound by discouraging reflections, but also seems to contain the sound quite nicely within the room.

Btw the HTM2D rests on the cabinet stand by means of 4 "stick-on" rubber feet.

[misterdoggy]

Shadow, Nice setup. You have a little bit of room to raise you htm2d a small amount more. I had Stuck on spike feet on my htm2d, which not only saw a slight improvement, but also looked good. This would bring your tweeters to being on the same horizontal plain. They say your tweeters in the front should be within 12 inches in height of each other.

I love the idea of the speaker on a cabinet and the screen ont he wall. I don't have the placement for it. If I did I might even splurge for the htm1d.

[ShadowZA]

Thanks, Doggy You've given me food for thought ... and a little experimentation :P

[JimTW]

Kal, Audioques, MrDawggie, and D-bucket,

Thanks for your responses.

The maker of the cabinet can leave the back open. So, that's what we will do.
Now, in terms of the side, how much space should I leave so that the side walls
left and right will have minimal effects?

I noticed in MrDoggy's picture of his setup, his center is sitting on the glass shelf
with the top very close.. our setup will be very similar to this. Now, if I can alot
enough room on the left and right, perhaps it could be just like MrDoggy's setup.
MrDoggy, does the glass on top being so close affect the sound quality of your
center channel?

Thanks!

[misterdoggy]

Kal, Audioques, MrDawggie, and D-bucket,

Thanks for your responses.


I noticed in MrDoggy's picture of his setup, his center is sitting on the glass shelf
with the top very close.. our setup will be very similar to this.
Thanks!

Important to note in my setup. The speaker is close to the top, but it extrudes the front plain. So the tip of the tweeter is about 1 inch "in front" of the shelf on top of it. So It has a free path out. The signal has nothing impeding in front. Its 360 degrees open.

[caleb]

Hi Shadow,
Lovely setup.
I am contemplating an upgrade from the "OLD" HTM2 to the "NEW" HTM2D.
I would love to come hear your setup.
Whereabouts are you in Cape Town?
RGDS

[JimTW]

Important to note in my setup. The speaker is close to the top, but it extrudes the front plain. So the tip of the tweeter is about 1 inch "in front" of the shelf on top of it. So It has a free path out. The signal has nothing impeding in front. Its 360 degrees open.

Yup, I saw some other pics of your setup. But, I couldn't see how much
forward the tweeter is. It almost looks flush to the shelf edge. Do you
have a better side shot of your setup? And MrDoggy, can you please
do me a favor? Can you measure the distance from the glass shelf the
center sits on to the bottom of the top glass? I'd like to know the distance
of space you have between the 2 pieces of glass (top and bottom) where
the center piece sits.

Tks!

[ShadowZA]

Hi Shadow,
Lovely setup.
I am contemplating an upgrade from the "OLD" HTM2 to the "NEW" HTM2D.
I would love to come hear your setup.
Whereabouts are you in Cape Town?
RGDS

Hi caleb

Thanks. PM me & we can set something up.

[Kal Rubinson]

Kal, Audioques, MrDawggie, and D-bucket,

Thanks for your responses.

The maker of the cabinet can leave the back open. So, that's what we will do.
Now, in terms of the side, how much space should I leave so that the side walls
left and right will have minimal effects?

As much as possible. In addition, try (1) rounding the edges of the surrounding cabinetry and (2) lining the interior to minimize reflections.

Kal

[JimTW]

As much as possible. In addition, try (1) rounding the edges of the surrounding cabinetry and (2) lining the interior to minimize reflections.

Kal

Kal,

Thanks. Now, with regards to lining the interior, how much of it should
be padded? All 4 surfaces? (top, bottom, left and right) Or just top and
the sides will be enough? Also, has to be professional sound absorbing
audio foam? Or just any old regular foam?

Thanks!

[misterdoggy]

Yup, I saw some other pics of your setup. But, I couldn't see how much
forward the tweeter is. It almost looks flush to the shelf edge. Do you
have a better side shot of your setup? And MrDoggy, can you please
do me a favor? Can you measure the distance from the glass shelf the
center sits on to the bottom of the top glass? I'd like to know the distance
of space you have between the 2 pieces of glass (top and bottom) where
the center piece sits.

Tks!

Its 36 cm. I took off the spike feet to make the tweeter level with the tweeters on the 802D's. 3cm clearance above the tweeter and extrudes 2 cm from the flat front (wood) and the tweeter is just a hair in advance of the edge.

Don't go by me though.

I will give you the best advice anyone can give you.

It will be you who decides whats best. Take all the advice you hear from the group, magazines, reviews etc, then put it to use in your room. Then its the fine tuning that will teach you the last leg. you can play with placement to find what sounds best, moving a little right left up down in out toe in toe out curtains, rugs, objects whatever and you will learn what needs to be done

Amen

[Kal Rubinson]

Kal,
Thanks. Now, with regards to lining the interior, how much of it should
be padded? All 4 surfaces? (top, bottom, left and right) Or just top and
the sides will be enough? Also, has to be professional sound absorbing
audio foam? Or just any old regular foam?
Thanks!

Foam? I'd suggest either acoustic felt or compressed fiberglas panels. If it must be foam, you want open cell foam. All exposed surfaces.

Kal