The best infinite baffle

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serge instrumental
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The best infinite baffle

Post by serge instrumental »

Would it be the best infinite baffle if I had two speakers in a wall and the room at the back of the speakers would be the same size than the one I'm listening in?

(but that would mean the speaker'mass and suspension being tuned for that purpose)
barefoot
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Post by barefoot »

Serge,

Yes, the speaker's mass and suspension would need to be optimized for this situation - unless you align the bass response actively.

There are three main tradeoffs with respect to box design - box size, low frequency extension, and efficiency. Improving any one of these parameters requires degradation of one or more of the others. A speaker with very low frequency extension in a small box must necessarily be inefficient. A high efficiency speaker in a small box must necessarily have limited low frequency extension.

The major tradeoff in your design is box size. A whole room is a rather huge box. Assuming the system is properly designed, you could have a very efficient speaker with very low frequency extension. High efficiency might not seem like such an important parameter in a control room where the listening levels typically aren't extremely high. The great thing about efficiency, however, is that it allows you to reach a given sound pressure level with less power. And less power means less distortion.

If I had the luxury of building a speaker like this, I would use an array of large, high linearity, high efficiency drivers - two Aura Sound NRT 18-8s per channel, for example. http://www.aurasound.com/proaudio/frameset2.html The natural f3 of this setup would only be about 90Hz. With active bass equalization, however, you could bring it down to 10Hz, critically damped, with a shallow 12dB/ocatave roll off! The tradeoff for all this deep tight bass is +16dB of gain at DC, but the efficiency of a pair of these drivers is a whopping 102dB/W/m. Subtract the 16dB and you get 86dB/W/m, which is the typical passband efficiency of most sub drivers. Driving these Aura speakers with a 200W amplifier could easily twist your guts and make your ears bleed in an average size control room. But a pair of these drivers can handle 1600W. 200W is nothing to them. So that gut twisting output would also be extremely linear!

Let me know if you need any help building such a monster!;) This would be a lot of fun!:D

Thomas
Thomas Barefoot
Barefoot Sound
serge instrumental
Posts: 112
Joined: Fri May 16, 2003 12:03 pm
Location: North of Montreal, Quebec

Post by serge instrumental »

I like theese numbers: 200watts for good bass! Imagine with another 1400watts per side for the dynamic range!

Oh :) I was only dreaming. Living in a coutry, building a 30'X40' for some nice home cinema and using about the half of it(with concrete blocks, filled with cement, for the middle wall) as a near empty summer/winter stockroom and the other part as a music/cinema room, it would be an interesting project (remember I'm dreaming!)

The structure would cost around CAN$22K(doing all myself)

Oh only dreaming of goood basssss! :P

Hope to turn on light to someone who has the money.... :D :D :D
serge instrumental
Posts: 112
Joined: Fri May 16, 2003 12:03 pm
Location: North of Montreal, Quebec

Post by serge instrumental »

In fact I would need a third room at the back to equalize(absorb) this low frequency enrergy with huge Helmotz resonnators :)

This would add another CAN$10K but when you pay US$100K just for monitors, this seems like a Yes Go FOR IT project :D
serge instrumental
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Joined: Fri May 16, 2003 12:03 pm
Location: North of Montreal, Quebec

Post by serge instrumental »

So well, what would you add for the 100Hz to 20KHz and+?

An array(at least two per side) mid/tweeter like this?: http://www.sunshineworldwide.com/booths ... ber_2.html

For the med-bass/low mids what would it be?(Were talking about a 3way system at least here, some ATC stuff?) :P :P :P

It is so fun that it can give some ideas to others! A dream system not so expensive when you compare top of the line monitors :P

Let's say $35K for the building, another $35K for the sound system (I think we have enough with sound!) and another $20K for video and whe are still under $100K for a super home cinema hall. (Ooops I've forgot the popcorn machine!) :oops: :oops:

Okay this is gonna be $10 dollars for the admission :D :D :D
serge instrumental
Posts: 112
Joined: Fri May 16, 2003 12:03 pm
Location: North of Montreal, Quebec

Re: The best infinite baffle

Post by serge instrumental »

I've finally went to the relalty.

Get my old drivers and built cabinets(6 cuft fot the K-145) to accomodate my listening room: a pair of JBL K145 and 2420 JBL drivers. Have to find a QSC or JBL waveguide (for the JBL 2420) and probably a good 8" or 10" cone driver to help with x-over and dispersion and power response, for mid-basss used for music or stereo DVD stuff: overall 3 way active. Use a Berhinger DCX el.Xover and tune the system with the help of software and a calibration mic plus an audio interface(already have the Digidesign MBox)

Any recomendations? :)
Soundman2020
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Re: The best infinite baffle

Post by Soundman2020 »

I can't see those being much use in a studio!

- Stuart -
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