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Old 27th April 2013, 03:35 PM   #101
NWCgrad is offline NWCgrad  United States
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ShadyDave and DrDyna, thanks for posting your results (even the subjective junk...I am glad to see they are easy to integrate with mains as I am planning to use mine as flanking subs (assuming I ever get re-assigned out of Asia).

The TC Sounds drivers do model well in this design, although they seem to work in most Lab 12 designs, except play louder to their greater extension.

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Old 28th April 2013, 01:48 PM   #102
DrDyna is offline DrDyna  United States
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Yeah, integration was really pretty easy here. It might even be easier once I've got two of them going, but for right now, I've just got them going directly from sub outputs to amplifier. I haven't even fussed with the MiniDSP, I've just got the amplifier gain set a couple of ticks lower than "noon" on the knobs and its basically forgotten. Granted that may change once I've got the media room sorted out and everything is back down in the larger room, but for now, its a very pleasant subwoofer that seems to have very few attitude problems.
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Old 1st May 2013, 02:49 PM   #103
DrDyna is offline DrDyna  United States
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I've sorta asked this before about the single fold design, but just to make sure, would there be any issues with building it like this? Or with the driver inverted?

(pardon the crudeness of my mspaint skills.)

Edit: I guess what I'm asking is, before I get creative, is there any style of folding or not folding that will affect the performance in any appreciable way?
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Old 1st May 2013, 04:14 PM   #104
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I always thought the original design was nothing more than a BR with a flare ended port. A T-TQWP or T-TQWT is a negative flare TH. A TQWT or TQWP is a straight flare TH.
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Old 1st May 2013, 05:03 PM   #105
DrDyna is offline DrDyna  United States
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Quote:
Originally Posted by BP1Fanatic View Post
I always thought the original design was nothing more than a BR with a flare ended port. A T-TQWP or T-TQWT is a negative flare TH. A TQWT or TQWP is a straight flare TH.
I rather agree, however (and I'm still learning about horns) I think the way the driver is positioned along with the thin-long design plays a role in tuning resonances, along with the way the upper end of the line should be stuffed, as I understood, lightly and increasing to heavy toward the far end.

If I build a proper pair of these once I can come up with a wacky design that I like, I'm not opposed to knocking the "internal artwork" out of this test cabinet I have now and measuring the difference.

I just need to come up with something artistic that doesn't compromise the performance before I start cutting BB.
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Old 1st May 2013, 06:17 PM   #106
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How build a regular BR (0.62, 1.00, 1.62) with the same volume and flared port, build the long box, and then compare all 3 enclosures' responses???
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Old 1st May 2013, 07:27 PM   #107
DrDyna is offline DrDyna  United States
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Quote:
Originally Posted by BP1Fanatic View Post
How build a regular BR (0.62, 1.00, 1.62) with the same volume and flared port, build the long box, and then compare all 3 enclosures' responses???
I was more or less just going to use the existing cabinet without the pieces that make up the fold, or even just reach in through the driver opening and poke a half dozen holes in it with a 4" hole saw.
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Old 2nd May 2013, 05:37 AM   #108
NWCgrad is offline NWCgrad  United States
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Quote:
Originally Posted by BP1Fanatic View Post
I always thought the original design was nothing more than a BR with a flare ended port. A T-TQWP or T-TQWT is a negative flare TH. A TQWT or TQWP is a straight flare TH.
According to Bjorno it is an Offset Driver Mass Loaded Transmission Line (OD ML TL), I searched the design on the Internet but didn't find much. Apparently the top section (ie above the driver) loads when the speaker is powered and acts as a spring to force sound waves through the "port." A typical ported design does not "mass load" in this matter. I am far from knowledgeable on speaker design and Bjorno seems to have dropped off the site.

Would be interesting the compare a traditional ported design tuned to the same value. Is there a measurable or audible difference? Traditional ported would be a much simpler build.

I wish I could change the name of the thread to OD-ML-TL vice T-TQWP. I was after a T-TQWP design to match the one Bjorno developed for my Maelstrom X 18" driver. I have heard it can be hard to mix sub types in a common space and obtain good results.
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Old 2nd May 2013, 12:26 PM   #109
DrDyna is offline DrDyna  United States
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Quote:
Originally Posted by NWCgrad View Post
According to Bjorno it is an Offset Driver Mass Loaded Transmission Line (OD ML TL), I searched the design on the Internet but didn't find much. Apparently the top section (ie above the driver) loads when the speaker is powered and acts as a spring to force sound waves through the "port." A typical ported design does not "mass load" in this matter. I am far from knowledgeable on speaker design and Bjorno seems to have dropped off the site.

Would be interesting the compare a traditional ported design tuned to the same value. Is there a measurable or audible difference? Traditional ported would be a much simpler build.

I wish I could change the name of the thread to OD-ML-TL vice T-TQWP. I was after a T-TQWP design to match the one Bjorno developed for my Maelstrom X 18" driver. I have heard it can be hard to mix sub types in a common space and obtain good results.
You should be able to get a moderator to change the topic, I remember reading that the design was really an OD ML TL, but if a few days goes by before I see the thread again, the topic always puts QWP back in my head when I'm discussing it.
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Old 2nd May 2013, 03:20 PM   #110
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Quote:
Originally Posted by DrDyna View Post
I was more or less just going to use the existing cabinet without the pieces that make up the fold, or even just reach in through the driver opening and poke a half dozen holes in it with a 4" hole saw.
That'll work too!
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