Home Theater Forum and Systems banner

141 - 160 of 261 Posts

·
Registered
Joined
·
580 Posts
Interesting that you have no smoothing and it is that smooth. Horns do load a room very differently than does a conventional box. You have great control over the directivity of the enclosure. It can be of great benefit to you.

Did you keep track of the power input into the enclosures on the power compression sweeps.

Looks like there is no compression and that the house was doing nasty things at the uppermost level!
 

·
Registered
Joined
·
193 Posts
Discussion Starter #142
I did not track the power output, but according to my calculations it should be right around 300 watts, so 50 watts per speaker.

It does seem that there is a minor amount of compression starting around 16-17hz, so it looks like this could be a perfect upper limit.
 

·
Registered
Joined
·
580 Posts
300 watts! Interesting.

I ran a simulation on the Impedance. it is here:

Andy's Sub Impedance plot.png

If you take a look at the impedance peaks, the largest one is at the Fc or tuning frequency of the horn. Eighteen hertz. The magnitude (or how high in value the impedance peak is) that is simulated does npt always agree with reality. But the location of the peak is pretty solid in my tests. The better the design and less leaks there are the more closely the simulation matches reality.

So what does this tell you?

Do a bit of number crunching on how much power your amp can push in around 16 to 18 hertz at that impedance. You will be surprised.

You seem to have a fair bit of test equipment. Would it be possible to run an impedance sweep on the enclosure as a single enclosure? Then we could do a bit of number crunching to see what's what in terms of power available into that kind of a load.
 

·
Registered
Joined
·
193 Posts
Discussion Starter #144
Sure, can do. Have a Woofer Tester 2 that I bought a few years ago, never used it yet so I will get it hooked up, and figured out.
 

·
Registered
Joined
·
580 Posts
I can walk you through that if need be.

I have set it up for clients, and I use the Woofer Tester Pro for my day to day work.

Just make sure you have your calibration resistor handy.

If you save the file as a .woo file I can open it up here. It can let me do a little more digging.

What amp were you driving the subs with?

I would be interested to see what it's voltage limit is. It is definitely not sinking much current at that impedance level.
 

·
Registered
Joined
·
193 Posts
Discussion Starter #146
The subs are wired to one channel of my XLS 402, max voltage output @ 20hz before clipping was 51vrms into a 8 ohm load bank
 

·
Premium Member
Joined
·
5,799 Posts
Reasonably close to Ottawa is I.

Great! basement. I luvs designing for basements.

You will have room reinforcement up to your teeth.
What would happen if you took a timber garage and made a cinder block room inside it... Would it be like a basement too?
 

·
Registered
Joined
·
580 Posts
What would happen if you took a timber garage and made a cinder block room inside it... Would it be like a basement too?
There are much easier ways to get that kind of isolation.

http://www.cgcinc.com/media/49251/ewb-w151_acousticassembly.pdf

http://www.owenscorning.com/worldwide/admin/tempupload/canada/30011340.pdf

You can makes walls that have better sound isolating characteristics that 8 inches of concrete.

Al depends on what you are looking for.

If you want some good clear answers on this topic please start another thread, and give me a link.

I'll be happy to help you out over there.
 

·
Registered
Joined
·
193 Posts
Discussion Starter #150
What would happen if you took a timber garage and made a cinder block room inside it... Would it be like a basement too?
That as Mark said is not optimum. The key with a basement is all the earth/fill that surrounds the walls.

Now if you where to pour a 36" thick concrete wall then build another room within that, would work good.
 

·
Premium Member
Joined
·
5,799 Posts
There are much easier ways to get that kind of isolation.

http://www.cgcinc.com/media/49251/ewb-w151_acousticassembly.pdf

http://www.owenscorning.com/worldwide/admin/tempupload/canada/30011340.pdf

You can makes walls that have better sound isolating characteristics that 8 inches of concrete.

Al depends on what you are looking for.

If you want some good clear answers on this topic please start another thread, and give me a link.

I'll be happy to help you out over there.
Gotcha... As soon as I finish my current project I will be ready to start the theater project and I will start my own thread.

That as Mark said is not optimum. The key with a basement is all the earth/fill that surrounds the walls.

Now if you where to pour a 36" thick concrete wall then build another room within that, would work good.
It just had me wondering because years ago Keith Yates Audio had a front wall that was concrete with like 6' deep of sand... That room sounded great!
 

·
Registered
Joined
·
683 Posts
The bass in your theater is going to be insane :hsd: This has been a really cool thread to follow; I'm looking forward to seeing how it all takes shape together! :T
 

·
Registered
Joined
·
193 Posts
Discussion Starter #154
Thanks. Looking forward to it also! The goal is more about the quantity of bass and lack of eq. The distributed sub setup has intrigued me for a while so I thought I would give it a shot and see how it goes.
 

·
Registered
Joined
·
193 Posts
Discussion Starter #160
Well I haven't tweaked the crossover or blend with the ULF subs, but so far I am more then impressed with how they sound!
 
141 - 160 of 261 Posts
Top