First DIY Speaker Build using in-ceiling donor speakers?

[Numbnuts]

Hi All,

About to pull the pin on the first stage of my new Hi-Fi set up. The ifnish list looks like:-

Pro-Ject 2XB Turntable
Pro-Ject Tube Box S2 Phono Pre-Amp
PrimLuna Classic Valve Amp

For speakers, I have some old Eltax floor standers to tide me over until I decide which way to jump but I remembered today I have some in-ceiling's that are essentially new (well, 10 years old but were never really used). I paid about a grand for them back in 2009 in our house build but we sold the house not long after we built and i swapped them out for some cheapies.

I think they are Niles CM730DSFX from memory but will check tonight when I get home.

My question is, is it worth my time building an enclosure or will these not be suitable at all used on a decent stero vinyl set up?

I was thinking an open back design, essentially mount them in to a vertical nice piece of timber or possibly acrylic with a base.

Would love to hear any thoughts or point me to some threads of anything similar, did a bit of searching an not turned much up.

Thanks.

 

[fatmarley]

They will need a new crossover because the original one wont have any baffle step compensation. As a result, low frequencies will be weak.

You'd be far better off selling them and building an established design from Jeff babgy, Tony gee or Troels etc...

 

[Numbnuts]

Shame. I was getting excited about the idea of building them into something. Been reading up on sewer pipe designs all day.

 

[system7]

8" Polycone with 1" concentric tweeter.

The installation manual says they are suitable for ceiling or wall mounting, presumably with a big cavity behind. Like another room or a chimney breast.

That's effectively what we call infinite baffle. The mechanical loss is doubtless in the Qts = 0.7-1.5 range, which makes them unsuitable for any reasonably small box.

Even some open back design had best be huge.

The old standard IEC testing baffle has some severe bass weirdnesses.

All looks like too much trouble to use them outside their design goals.

 

[phivates]

Niles wasn't junk. What about eq to handle baffle step, or a proper old school wide baffle?

 

[Numbnuts]

Thanks for the replies.

I think I'll just leave them in the cupboard until such a time we ever live somewhere I can put them to use again as in ceiling surrounds.

Probably not worth listing them on eBay for whet I'd get for them, may as well leave them there until I can use them for something they were designed for in the future.

I got the new turntable set up the other day, sounds amazing on my cheap old Eltax floor standers through a $50 photo pre-amp and into my old Yamaha theater amp, so I'm a bit loathed now to try and build something on the cheap from the Niles. I'll save up a bit longer and treat myself to some decent quality floor standers instead.

Ordered a Pro-Ject Tube Box S2 valve phono preamp this week and hoping to add a PrimLuna valve amp in the next few months so I'll be looking for some nice floor standers to compliment that set up.

Cheers.