Time To Start Building

[Silent Screamer]

Now that the cat's out of the bag I have little excuse to not starting building some speakers (with the exception of I need to build a new house and get a job, but other than that no real excuses)

 

I have gone through my boxes of drivers that have been waiting patiently for me to pull my finger out and did a stocktake of what I have.

 

I want to build 7.X channels for a home theatre room / possible music.  Here are some of the drivers I have available:

 

2 x RAAL 140-15D AM Dipole (93dB 8ohm) – Will probably just sell these down the track.

3 x RAAL 140-15D AM Monopole (95dB 8ohm 200w Filter recommendation 4^th order LR @1600) Front 3 channels

4 x RAAL 70-10D AM Monopole (91dB 8ohm 150w 4^th Filter recommendation order LR@2800) Rear 4 channels

4 x Scanspeak 4.5” 12MU/4731 (90db 4ohm 80w)

6 x Scanspeak 4.5” 12MU/8731 (87.2dB 8ohm 80w)

10 x Scanspeak 7” 18WU/4741 (87.2dB 4ohm 80w)

Links:

http://www.raalribbon.com/products_flatfoil_140-15.htm

http://www.raalribbon.com/products_flatfoil_70-10.htm

https://www.madisoundspeakerstore.com/approx-4-midrange/scanspeak-illuminator-12mu/4731t-00-4.5-midrange-4-ohm/

https://www.madisoundspeakerstore.com/approx-4-midrange/scanspeak-illuminator-12mu/8731t-00-4-midrange/

https://www.madisoundspeakerstore.com/scanspeak-woofers-6-7/scanspeak-illuminator-18wu/4741t-00-7-woofer-4-ohm/

 

2 x TC Sounds Pro 5100 (subs / mains?)

1 x TC Sounds LMS Ultra 5400 + 2 x 18” TC Sounds VMP Passive radiators (sub box)

 

I would like to get the forums input on how you would arrange the drivers and preferably why you would make that choice. This will be passive so please consider the X-over.

 

 

Edited August 1, 2017 by Silent Screamer

[Guest]

Wow, what a classy build sweet ribbon zone. Would prefer them out of their shoe boxes for, with out clothes packaging for the photo shoot thanks.

Quite like the "look" of the set up on your left side, groovy.

 

Appreciate the fact it will be a fairly monumental amount of work for the "full monty" surround system on completion, so at this stage my humble suggestion and more of a process rather than arrangement is get the stereo front pair  so as you like it a lot first, with the sub (subs integrated) Then (as each build is done) run each pair of speakers as a stereo pair up front for a while  to ensure they also are to your taste doing all the right things like image and staging properly. Build the centre speaker and again tune to liking ensuring it sounds almost as good as the front stereo pair, in mono, which is achievable  .

Sticking to normal rules/guides associated with placement of the 7.X at that point of the build would be a great starting point

Beyond that sounds like blissful and dynamic surround, have fun bit envious actually you have some really special drivers there

 

[Hippy]

Youre going to have a LOT of fun. I for one expect to see some great things off that CNC

THB I don't know how you'll find time to do any jobs for yourself once word gets out. Most of my free time is taken up cutting stuff or making stuff for other people (for either grog or money).

[acg]

I think Matt has put forward a good plan:  start with the stereo pair, sub's, then the rest of the 7.1.  One thing to be aware of is the limited vertical directivity of ribbons.

 

Personally, I would get the mids and upperbass optimised first...say 100Hz - 5kHz or thereabouts.  That sets the tone for the system, especially the couple of octaves 100Hz and up.  Then work at either extremity.  Lots of experimentation to be done! 

[Silent Screamer]

27 minutes ago, Hippy said:

Youre going to have a LOT of fun. I for one expect to see some great things off that CNC

THB I don't know how you'll find time to do any jobs for yourself once word gets out. Most of my free time is taken up cutting stuff or making stuff for other people (for either grog or money).

There is a full kitchen and two big bathrooms in that CNC's future. I am hoping to recover the cost by DIYing them.

[Silent Screamer]

I did a bit of reading yesterday to try and get some idea of what the current requirements are for the rear channels. I was half hoping to just get away with a 2 way for the rear four speakers. With just the small RAAL 70-10 and a 12MU in each, I would only need a cabinet of a couple of litres.

 

I was looking to make cabinets similar to the Sonus Faber Elipsa (but in searching for an image see they make something very similar to what I had in mind). The idea was to make them eliptical to bolt them to the walls at the rear. But to get down to the lower frequencies I might need to go to 3 way, which then means an additional 20+ litre cabinet spoiling the tiny speakers I had in mind.

 

I could build the two way cabinets as planned and build the woofer in a separate cabinet but that does seem like a lot of messing around.

 

The fronts and centre I don't see being all that much different to the current speakers. I was thinking 1 x 140-15,  2 x 12MUs and 2 x 18WUs in each. If I didn't use the 18WUs on the rear I could make the stereo pair 4 x 18WUs each, but that would leave a significant size difference front to back.

 

So 3 way on the rear seems the most sensible way to go.  I guess the only thing to work out is what kind of cabinet design. Because the rears are generally closer to the seating position than the fronts do I want to curve the box for a focused point like the Focals?

[Guest]

Interestingly enough the Dolby THX set up calls for and recommends baffle speakers for the rear set (can't find the literature I read some time ago though someone else may know) 

 

 https://www.dolby.com/us/en/guide/speaker-setup/index.html

[Silent Screamer]

Spend the day chasing up old Sketchup files and drawing. Playing with the idea of something like this.