Taking the Air Cavity/pre-chamber to the next level...

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frugal-phile™
Joined 2001
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Once the blocks were in it worked really well with A7 and EL70, and is no longer suited for FE126. Valiant has a deeper air cavity and is wider internally, so by decreasing the volume of the air cavity we have made the horn incompatible with FE126. This same treatment is easily doable in all of the new Woden rear mouth horns as long as you plan ahead.

dave
 
Is Olique the same as Isometric

Allen,

Is it possible to get a couple olique photos?

dave

Are these "olique" photos? I remember Isometric from drafting class in school a while back... ... is that the same as olique? This difuser is hard to get the light right. Here are three diferent lighting arrangements of this difuser in an Isometric composition. Let me know if you prefer a diferent composition .
 

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Once the blocks were in it worked really well with A7 and EL70, and is no longer suited for FE126. Valiant has a deeper air cavity and is wider internally, so by decreasing the volume of the air cavity we have made the horn incompatible with FE126. This same treatment is easily doable in all of the new Woden rear mouth horns as long as you plan ahead.

dave

Thanks for the info dave. At the very least it would mean that my upcoming Valiant would have an "upgrade path" open if ever I find in the future that the A7s are more to my tastes.:)
 
was not the "issue" that as our bastardization of Scott's Maeshowe (originally designed for the Mark Audio drivers) for use with the Fostex FE126 significantly increased the volume of driver chamber - beyond that in which the Alpairs( or EL70) would be at their best? IIRC they sounded quite bloated and colored without reduction of the chamber volume

the staggered blocks make a lot more sense than canned fish (or water chestnuts ;))
 
frugal-phile™
Joined 2001
Paid Member
The theory is that the volume of the air cabity, the exit to the horn, and the driver parameters controls the cut-off frequency going into the horn, Larger = lower.

The goal for a smooth hand-off is that the distance from the start of the horn to where the horn output merges with the output of the front of the driver is an odd number of half-wavelengths of the cut-off frequency.

dave
 
Is there a particular frequency range that the diffusor should be built for or is the air volume the primary factor in the design.

From a symetry point of view, would a slat diffusor work just as well or possibly better than the 2D diffusor? Theoretically, 2D diffusors disperse sound in a verticle and horizontal direction. Where slat diffusors only scatter sound in one direction. Could this be used to your advantage here?

There is enough space available behind the main air chamber in the Maeshowe to allow for a fully adjustable air cavity. Where you could allow the diffusor to move forward and back changing the air volume behind the driver. It could also allow you to make the diffusor a little deeper if a lower tunning of the diffusor is required.

Is any of this worth trying?
 
I planed to, just making sure I'm not wasting time.

But what frequencies would you suggest I try to control with the diffusor? Is ther a particular range that is troublesome for the EL70 and this design? The reason I'm asking is because I don't want to build the diffusor so deep as to cause issues with the low frequencies reproduction. I know the wave forms are much to long to be effected on their own, but mid frequencies often reinforce lower frequencies.
 
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