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Discussion Starter #1
Did i read somewhere you can't really port this if it comes alive, due to port resonance?

Is a resonable llt obtainable, or too many issues? (not that you would need to port this beast.... Ib or huge sealed.)
 

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It is vaporware at this point because we don't have a manufacture that will make them for anywhere near the cost requirements. Maybe if the economy gets slow enough they will change their minds but right now I'm not going to do a production run of transducers that cost $3K each. They wouldn't sell in enough quantity to justify the investment.

The original plan was to make them with Passive Radiators. Ports become problematic due to the lengths required in the box size we targeted.

Kevin Haskins
Exodus Audio
 

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Discussion Starter #3
What were you targeting? I assume at some point a large enough enclosure would allow a short enough port? But at that point, does the air mass really still act as a suspension and the port fully function?

I think I read a 10" port would suffice? Or at least 12"?
 

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Nope.... do the math. A 21" driver with this kind of stroke designed to work in a 8-10 cubic foot box just doesn't work with ports that tune the enclosure down around 18Hz.


Kevin Haskins
Exodus Audio
 

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Discussion Starter #5
What I meant was if you built say 20-50 cubic feet, what would the problem be? I dont have my modeling software anymore, and Im no expert to begin with, so IDK what math I would do.

If a guy built a 50 cubic foot box, with a 12" port, would it be good, or bad? and why if you dont mind....
 

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Well... there just are not that many people willing to build 20-50 cubic foot boxes. We design the driver parameters around a given box size and application.

Ports are just a bad idea with this kind of driver. You get too much noise from chuffing, too long of lengths, excessive volume requirements, port resonances etc... The PR route solves all those problems and for people willing to spend $2K-$3K on a driver they are not worried about spending a little more on a couple passives.

Kevin Haskins
Exodus Audio
 

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Discussion Starter #7
not that this driver needs PRs, ports, or anything.... just seems like it would be fun to have a 12" port tuned to 14Hz.... Oh to crawl inside of that!

What types of things are holding it back? I know 21" is large, and the Xmax is extreme as well, but I guess I don't see why a "normal" high excursion basket wouldn't accomodate... be it the normal spoke basket or a TC sounds type.... what have you, just larger proportionately..
 

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The entire thing requires special tooling. There isn't anything in the design that could use an off-the-shelf part. It represents the bleeding edge of driver development and the cost to tool up all those parts is substantial. We are in an economic downturn so it isn't the type of product I'd consider as practical in the current business environment.

Kevin Haskins
Exodus Audio
 

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If a guy built a 50 cubic foot box, with a 12" port, would it be good, or bad? and why if you dont mind....
It depends on the TSP's. The Sick-o was geared more towards a box 1/5 that size. Having one that big, would make it extremely peaky at the tuning freq. For example, model a ported subwoofer that ends up being fairly flat. Now multiply that box size by 5 and see what happends to the response. Adjust the tuning freq if you want. Either way, it won't be pretty.

If you did have 50ft^3 available, dual Tempest's or dual mal-x's would work great and you'd save quite a bit of money.
 

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"thats what i was thinking, but wanted to make sure, cuz Kev said NO GO!"

What he said was

"there just are not that many people willing to build 20-50 cubic foot boxes. We design the driver parameters around a given box size and application.

Ports are just a bad idea with this kind of driver. You get too much noise from chuffing, too long of lengths, excessive volume requirements, port resonances etc..."

If you are willing to use a huge box, I don't see why the noted issues aren't addressed.

Use a modeling program to see how big of a box it takes to get a reasonable length with a large diameter port, which is the crux of the issue.
 

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Discussion Starter #17 (Edited)
little grasshopper may be ready for the next level here...

I thought any speaker could be put into a huge box, sure some a little better than others.... what makes one peaky in a large box, i'm assuming at Fs? and others OK in over sized?

( I would have thought every speaker would be peaky at it's Fs more and more the larger the enclosure, or in an IB)
 

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Discussion Starter #18
If you are willing to use a huge box, I don't see why the noted issues aren't addressed.
my sentiments exactly, that was exactly my feeling, eccept:

1: this news to me that certain drivers suffer from peaky responce from larger enclosures more than others

2: this driver being designed for a specific range, happens to suffer more than others will from that condition (peaky)

3: at some point, does too much volume make it no longer act as an enclosure.... (if you "port" an IB, does the "port" still function?)
 

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"this news to me that certain drivers suffer from peaky responce from larger enclosures more than others"

The higher the driver's Q, the peakier it will be for a given Fb. Lowering Fb will fix it, depending on Q.

Depending on the driver, I suppose it's possible that the required box size makes LF so efficient that there will be a peak no matter what.

"at some point, does too much volume make it no longer act as an enclosure.... (if you "port" an IB, does the "port" still function?)"

I believe it will be a tunable enclosure for any conceivable real volume.

At some point the length of the port will bottom out at the thickness of the enclosure wall, and the only thing that can be varied is its area.
 
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