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Old 8th March 2013, 11:23 AM   #1471
KLBIrd is offline KLBIrd  United States
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Cal is not a hobbyist hes a speaker distributor in disguise!
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Old 8th March 2013, 10:13 PM   #1472
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Hey X, what did you do? Is a constrictor vent a type of aperiodic loading?

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Cal is not a hobbyist hes a speaker distributor in disguise!
hehe aka Speakerholic.
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Old 8th March 2013, 10:15 PM   #1473
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I found the trick to the Penthorns. You medium damp the chamber, lightly damp the throats and only damp 3 of the 5 horn mouths.

I think I have it. That sounds pretty good by George.
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Old 8th March 2013, 10:32 PM   #1474
guangui is offline guangui  Puerto Rico
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I modified my earlier folded TL stereo wall mount speaker to be a MLTL by adding a constrictor vent. The bass response is much better now. I did not do a full sim, I just ran WinISD to calculate a BR vent based on volume and added the vent at the end of the line. The TL has stuffing in the first 2/3rds and now reaches down into the 50 Hz region with tight punchy bass (see freq response of vent before and after constrictor vent was added).

How does it sound? It sounds great! Very nice office/bedroom speaker and gets quite loud with good stereo separation considering the drivers are about 2 ft apart. Once decorated with a painting or poster, it will blend right in. The bass is very good due to wall loading and of course, no BSC is needed.
Doesn't the measured freq. range looks "erratic" in the 400 to 2.8k Hz range? Maybe your enclosure design is more suited for a 2-way of a mid-bass or FR speaker with a tweeter?
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Old 8th March 2013, 11:38 PM   #1475
xrk971 is offline xrk971  United States
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Doesn't the measured freq. range looks "erratic" in the 400 to 2.8k Hz range? Maybe your enclosure design is more suited for a 2-way of a mid-bass or FR speaker with a tweeter?
This is just the vent output. So that's just the higher freq components leaking out of the bass port - rather low level. Notice how constricting the terminus really reduces the HF junk. The majority of the mids and highs are dominated by the direct radiation of the driver.
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Old 8th March 2013, 11:39 PM   #1476
xrk971 is offline xrk971  United States
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Quote:
Originally Posted by Cal Weldon View Post
Hey X, what did you do? Is a constrictor vent a type of aperiodic loading?




hehe aka Speakerholic.
It's still periodic, just turning it to mass loaded transmission line - lowered the tuning freq by mass loading the vent.
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Old 9th March 2013, 12:10 AM   #1477
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periodic
At this point in my life, there's something I don't like about that word.
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Old 9th March 2013, 02:50 PM   #1478
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I have trouble venturing a guess how low it goes
Ran some test tones. I don't have a mic to measure with but...

20 - nothing
40 - something
60 - just fine
100 - too much
200 - too much
400 and up - just fine
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Old 9th March 2013, 02:54 PM   #1479
RAW is offline RAW  Canada
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Cal.
If ya ever want those things measured drop me a line and we can fire up Praxis.
Sounds interesting to see what these measure like.

Al
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Old 9th March 2013, 03:10 PM   #1480
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Hi Al,

Thanks for that offer, I know you're always there and I appreciate it but... there's a reason I don't own a mic.

I am much happier not knowing how they measure, at least I can still enjoy them
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