I've built a few speakers based on kits, but I'm interested in playing around with making a cheap transmission line sub for my car's trunk. I built a small t-line based around the Tang Band W3-1876 and love the way it sounds, especially for its size.
I'm interested in using PVC and a speaker to make it an easy/cheap build. I am planning on getting a Tang Band W6-1139SIF. I don't quite understand what diameter tube I need to use to make this work out well. From what I've read, the length should be the Fs wavelength / 4. In this case the manufacturer t/s reports the Fs is 35Hz so I calculate 96.857". The Sd is 140cm^2 (21.7in^2). I thought I've read that the diameter of the transmission line should be close to the Sd, so could I use 3" PVC? The inner diameter of 3" PVC is about 29in^2.
Is there anything else I should know?
I'm interested in using PVC and a speaker to make it an easy/cheap build. I am planning on getting a Tang Band W6-1139SIF. I don't quite understand what diameter tube I need to use to make this work out well. From what I've read, the length should be the Fs wavelength / 4. In this case the manufacturer t/s reports the Fs is 35Hz so I calculate 96.857". The Sd is 140cm^2 (21.7in^2). I thought I've read that the diameter of the transmission line should be close to the Sd, so could I use 3" PVC? The inner diameter of 3" PVC is about 29in^2.
Is there anything else I should know?
Yeah, you can forget all that stuff about the TL needs to be tuned to Fs and the diameter (really the cross-sectional area) needs to be equal to Sd. That might be useful to create a bass-whistle, but a lot less so for creating a good TL. You can consider them as STARTING POINTS, but the length and cross-sectional area will need to be adjusted to get the smoothest response down to the lowest frequency that you want your TL to reproduce.
For some hints on how to do this using Hornresp, see The Subwoofer DIY Page - Transmission Line Systems
For some hints on how to do this using Hornresp, see The Subwoofer DIY Page - Transmission Line Systems
You can think of a rear-side pipe as being like a bass-reflex tuned thingy or like a sealed box and the bigger the better.
I'm of the belief that there are various OK ways of disposing of the rear wave and a long, well-damped pipe venting far from the driver is a good way. The less tuned stuff in your system, the better the sound.
B.
I'm of the belief that there are various OK ways of disposing of the rear wave and a long, well-damped pipe venting far from the driver is a good way. The less tuned stuff in your system, the better the sound.
B.
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More than I have time to type, so instead attached are two different alignments worth using depending on the needs of the app [need Hornresp to IMPORT, view] and the 'last word' on TL theory/design: Quarter Wavelength Loudspeaker Design
