2-way monitor design for HT

[INM8]

Hi, I have started working on a project to build a 5.1 HT setup for my parents living room. Nothing is in concrete yet, but there are two things I am fairly sure about:

- The subwoofer will be an infinite baffle sub, with either 4 x 15" drivers, or 8 x 15" drivers, located in the roof cavity.

- Floorstanding mains will be too big

Now I am at the stage where I need to pick out a design for the left, right and center speakers. From what I have read (remembering that I am a bit of a noob with only one sub project under my belt) it seems like keeping the front three speakers identical is a good move. However, due to dimension constraints finding an appropriate design has been difficult.

Here are the requirments:

- If I am building three identical fronts, the design will have to be less then 330mm high to fit below tv.

- Due to FAF (family acceptance factor) the speakers will have to be fairly discreet, meaning anything with a depth greated then 250mm is out.

- It would be good if I could wall mount them, but I can improvise with some sort of stand if need be.

So far, the only possible canditate I have found is the RZ-5v. Is anyone using these for HT purposes? Or are there better candidates?

For the surrounds I plan to use some small full range drivers (probably tangband, or whatever else I can get my hands on here in AUS) in a switchable dipole\monopole design. Basically I just want something that I can ceiling\wall mount at the back of the room , which is why I don't want to use a stock MT design, which will probably be too directional.

Anyway as I said, nothing is set in concrete, so im open to all suggestions . Thanks in advance.

[INM8]

Ok, so im not allowed to edit my posts yet, so I'm posting a bit of a clarification:

First of all, here are some pictures of the tv area where the front speakers will be located:

Image 1

Image 2


That should give you a good idea of what I am working with.

Also, when I asked for "better candidates", I should have been more specific in saying "better canditates that work with the dimension constraints and other criteria that I have listed". One thing to keep in mind is the availability of drivers down here aswell. Vifa, Peerless. and ScanSpeak are the easiest (and cheapest) for me to source, but I can get seas and some dayon products if need be.

[sreten]

http://www.humblehomemadehifi.com/USB.html

Possibly ?

Vifa D27TG-35-06 (or D27TG-45-06) / P13WH-00-08 2-way Loudspeaker
Alternative 2:
R1=4R7, 0.47mH, 6.8uF with tweeter connected with +ve polarity.
This crossover has the flattest response of the 3.

If this means no BSC then a good candidate for in-wall mounting.

/sreten.

[INM8]

Yeah I actually considered that at one stage, because I would be able to flip one horizontally for a center speaker, but two things held me back:

- Expensive drivers: Those seas drivers cost about $200 each down here.

- Depth: I dont really their size would help me in getting everyone else hear to accept them in the room.

Also, I think you misunderstood me when I said "wall mount". By "wall mount" I meant that preferably the speaker would be light enough to be mountable to a 5-10kg bracket. Ironically enough, if I had thought of it earlier I could have had them in wall, since that whole thing is built over an old fireplace (that kept me busy over Christmas), but everything has been plastered nicely now, so cutting any holes now is probably out

[rabbitz]

Originally posted by sreten
If this means no BSC then a good candidate for in-wall mounting.

/sreten.

Yep... No BSC on that xo. The other variations have about 2dB BSC which isn't much but it's effective. This is the speaker that's in the Wiki.

[sreten]

Hi,

Well the other variations with 2dB BSC should suit close wall mounting.

/sreten.

[rabbitz]

They certainly do and have mine within 40mm of the back wall. They rely heavily on boundary reinforcement.

[INM8]

Alright, well I think I may go with the RZ-5v then. Would I ruin the design if I made the enclosure sealed and reduced the depth?

[sreten]

Originally posted by INM8
Alright, well I think I may go with the RZ-5v then.
Would I ruin the design if I made the enclosure sealed and reduced the depth?

Hi, the very short answer is no, not at all, will be better for AV, /sreten.

[rabbitz]

If you go for sealed, make the depth 109mm which will keep the box ratios intact. This will give a sealed volume around 3.7 litres and an F3 around 130Hz (F5 around 100Hz). Make sure the box is 100% stuffed with damping material. The close proximity of the rear wall is believed to cause backwave problems, but those I have tried have experienced no problems and was benficial on one speaker.... go figure. The magnet on the P13 covers a lot of the backwave. Radius or chamfer (6-10mm) the driver cutout on the inside to help with airflow.

You might get a bit of an underlap in the crossover to the sub on the LFE channel but wall loading should help. You may be able to compensate in the HT receiver by raising the sub crossover but not too high as then it can become directional.

The only trade off with sealed is slightly reduced power handing, increased cone excursion and a higher F3 but for HT should not be a problem.