Mcm 8" 55-2421 Ts parameter - Page 3 - diyAudio
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Old 10th July 2011, 02:27 AM   #21
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[QUOTE

Or are you looking to these designs as folding inspiration and want to make a smaller version that takes a pair of mcm's? (which is what I assumed)

It would be kinda cool ....[/QUOTE]

Jebll you are correct I am look at these folding as inspiration or if EPA can come up with something better his folding skill is excellent.
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Old 10th July 2011, 10:41 PM   #22
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Default One more from tda

inspiration bass horn folded for 2 mcm8 driver.This one look ez to build.

one more.jpg

Last edited by kornnylike; 10th July 2011 at 10:48 PM.
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Old 10th July 2011, 11:14 PM   #23
jbell is offline jbell  United States
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The problem I have with tda's or other designs with separate audio paths for each driver as it relates to mcm's, is the scale of the horn path close to the throat. At 8:1 compression, that's 25cm2, which if you have an 8" tall path to house the driver... that's 1/2" by 8"....

Wow... that's tight. The other thing I remember distinctly was that at high of compression ratio, 1/2" x 8" sounds different than 2"x2"... they are both the same area, but it's not the same. A more square aspect ratio works much better.
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Old 10th July 2011, 11:32 PM   #24
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Quote:
Originally Posted by jbell View Post
The problem I have with tda's or other designs with separate audio paths for each driver as it relates to mcm's, is the scale of the horn path close to the throat. At 8:1 compression, that's 25cm2, which if you have an 8" tall path to house the driver... that's 1/2" by 8"....

Wow... that's tight. The other thing I remember distinctly was that at high of compression ratio, 1/2" x 8" sounds different than 2"x2"... they are both the same area, but it's not the same. A more square aspect ratio works much better.
Jbell can you post a drawing of a folded similar to my last post that might work.

Thanks
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Old 11th July 2011, 01:56 PM   #25
jbell is offline jbell  United States
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Originally Posted by kornnylike View Post
Jbell can you post a drawing of a folded similar to my last post that might work.

Thanks
not really -- that's kinda my problem. When you start with 25cm2 horn path area at the throat for a single driver, and you have 2 drivers, both using distinct paths -- you end up with more wood than air close to the throat. Also knowing that high aspect horn paths (1/2" x 8" for example) seem to not sound as good at this small of dimension, makes it difficult to to create a 'simple' horn path like what you posted. (It also means your box is goofy looking as it is only 8" in one dimension....)

Also keep in mind, just because you shrink a specific cabinet down in size from 18" driver to 8" driver -- you can't just keep the same number of folds, as those lengths get shorter, and so the box doesn't play as low. More folds are needed. (I know I'm stating the obvious here, apology)

The only way I know to make a dual mcm work REALLY WELL, involves a fold where both drivers fire into a common compression chamber, and then that chamber exits into a single horn path. Once you start there, then about any fold you can dream up works.

So... if you are looking for inspiration for a fold, try and look for something with both drivers firing into a common path.
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Old 11th July 2011, 02:40 PM   #26
tb46 is offline tb46  United States
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Hi kornnylike,

For what it's worth: I tried to redraw the Decware WO32 with the MCM 55-2421 in mind, and ended up with an enclosure that has a very peaky response, and is 6dB down @ 50Hz. The path is just not long enough. But I'll post it if you are interested.

I agree with jbell that you would be best served with something along the lines of littlemike's box that I pointed out before.

Regards,
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Old 23rd July 2011, 04:47 PM   #27
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Please be advised that this thread is not dead.
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Old 23rd July 2011, 08:06 PM   #28
MartinQ is offline MartinQ  Canada
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Originally Posted by kornnylike View Post
Please be advised that this thread is not dead.
This information has been taken under advisement.
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Old 30th July 2011, 08:10 PM   #29
epa is offline epa  Netherlands
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why not go with the plans in the topic oliver sugested in post 10.
its all worked out and fits your requirements .
or ask jbell for his flh plans they seem to work fine 2.
no need to reinvent the wheel.
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Old 1st August 2011, 04:31 PM   #30
epa is offline epa  Netherlands
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whats x-max of this driver ?
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