PVC Pipe Speaker help needed, please.

[sjturbo]

I have found an idea I think I would like to try. bogdan (https://www.diyaudio.com/forums/members/bogdan2011.html) built a pair of PVC pipe speakers using some drivers he had laying around. Listening to the ytube clips they sound very good. My intention is to build a pair to use as rear surrounds in a 7.1 system. I would like to use Dayton PS100-8. They seem to have a good rep as a full range speaker. He uses a "sanitary T" as a "port" at the bottom. So I don't know whether to call this a Transmission Line or Ported enclosure. My other question is, based on which type this would be considered what design formula could I use to match the speaker to the enclosure. I would like to make this an uncomplicated project and not use a crossover if possible or only use it to roll off the bass. Any suggestions?

 

[U130421]

The PAK-PAK speaker good for 2-3 inch full range. You need a T and 1m +0.5m PVC tube and a cap. If satisfied, you can cover fiberglass/resin.

 

[sjturbo]

Thanks for the idea. I really would like to use the Dayton PS100-8 in the construction as well as using the 4" size.

 

[U130421]

Dayton is an excellent candidate 110hz (Pak Pak) with 3inch tube.(diaphragm area). With 4inch tube it becomes too vulgar looking in the corner, matter of aesthetic.

 

[sjturbo]

Thanks. I'm not too worried about the aesthetic issue. They won't be that visible, and I kind of like the industrial look.

 

[U130421]

You don't need 10mn to assemble. You only need to adjust the absorbent in the under open side , not to have boomy sound . On the contrary what you may think the resonance falls due to air mass of the acoustic load and delivers very deep bass . This why it should have high resonance.

 

[GM]

So I don't know whether to call this a Transmission Line or Ported enclosure. My other question is, based on which type this would be considered what design formula could I use to match the speaker to the enclosure.

We refer to vented high aspect ratio cabs [MLTL], which can be simmed in Hornresp or similar that can do TL/horns.

Normally, HT surrounds, subs are XO'd at 80 Hz, but this driver ideally needs a 120 Hz XO, which means they must be closer for best sound 'immersion'.

Is the driver facing up or forward?

What is average seated ear height or higher height it must be at minimum?

GM

 

[U130421]

Both mine and Bogdan's are tapered quarter wave tubes. I had the intention first to have it 1/3 close 2/3 open as bogdan's ,but changing the opening side and firing the corner gave much more powerful bass . So bogdan's is 1/3 2/3 mine is 2/3 1/3 . You can try them both and choose.

 

[sjturbo]

TQWT in PVC, very interesting! How do you do the taper inside a tube? Seems like it would be very difficult?