recent transmission line design?

[Havoc]

I haven't been following the loudspeaker stuff for years due to lack of space and time. But now, the surrounds of my bass speakers have disintegrated so replacement is needed. But my documentation is dated as well.

In the meantime I bought a pair of PMC DB1's for the computer and I love them. They are fine next to the pc but too small for the living room. So the idea was to make a pair of transmission lines. That looks smaller than horns and almost as pleasing.

So, I would like to have a design that is not to demanding in woodwork, uses recent speakers (but nothing exotic) than can be easily obtained in europe. Nothing too large but not something to hide under the sofa either. Prefer a 3-way, all in one box no sub needed system. Room is about 100m³.

Has anyone something around?

[Gasho]

Why you don´t just build a T- line active subwoofer , and use small PMC´s like satelite loudspeakers?

[Havoc]

I'm not very fond of subs.

[Scottmoose]

Try the Seas Thor kit. It's a 2 way, but with these drivers and their crossover you won't need a 3 way. Providing, of course, you don't use the original enclosure design, which is, not to put too fine a point on it... sub-optimal. Unless, of course, you like your speakers to roll off below around 200Hz.

You could try this with them though. It's what I call my 'Small Thor MLTL'. Build an MTM enclosure 45" tall, 7 1/2" wide and 12" deep (internal measurements assuming 3/4" material is used). Add a port of 3" diameter, and 3" length. Stuff from the top of the cabinet to just below the lower mid-bass driver with something like Dacron hollow-fibre, 0.5lbs ft^3. No, that's not a bass-reflex enclosure. It's an untapered, mass-loaded quarter-wave resonator (a straight transmission-line in other words that vents via a port, rather than terminating in free-space). You'll get solid output in-room down to circa 30Hz (understatement: you'll get some serious bass-heft with this -too much in a small room), with that lovely pure midrange that is the reason to use a QWR design in the first place. For more information on Transmission Lines, first port of call should be Martin King's site at www.quarter-wave.com if you haven't already.

Hope this helps
Scott

[planet10]

Originally posted by Scottmoose
my 'Small Thor MLTL

A drawing of that is on my list for the sidebar of the "revisting Thor" article....

dave

[Scottmoose]

I like those bipolar floor-standing mini-onkens for the FR125 up on the site Dave -I hadn't noticed them before. Happy New Year to you and your family BTW.

All the best
Scott

[planet10]

Originally posted by Scottmoose
I like those bipolar floor-standing mini-onkens for the FR125 up on the site Dave -I hadn't noticed them before. Happy New Year to you and your family BTW.

Yes those will be interesting. The miniO is the standout monopole, but the bioles (sealed) trump them so a bipole version of the miniOs might well bring theb est of both. We had wood all cut for a set, but we sold another set of raw cabs and used the pieces for a monopole set... in the new year sometime.

dave