Ported, Sealed or Transmission Line

I sound like a broken record, but Sean makes a lot of good points.

While I also don't have a lot of experience with aperiodic enclosures, Bud is a big fan of them in certain instances. The transient response is supposedly improved, and the impedance curve is noticeably flattened - resulting in a more "resitive" speaker. Personally, as a tube guy, I don't get so panicked about high impedances (my Atmas love them) it's the low impedances I am more worried about.

The Fried Beta used an aperiodic enclosure, and Bud (who likes sealed boxes, just not as much as a TL) tells me it was the only way to get bass out of the small box. It makes the box size "appear" larger.

While I hope to do a lot of testing in the next 18 months, it would be interesting if we had some more A/B testing going on with between sealed and aperiodic boxes. Off the top of my head, I can't think of why a standard sealed box would be superior. And, you don't need to rely on Dynaudio or ScanSpeak's variovents. A lot of people just use a resin shower drain they get from a home improvement store, and foam or layers of gauze or felt.

Eldartford, as you said, "to each, his own", but I find the bass of electrostatic speakers to be less powerful and extended than a full range loudspeaker. They do have a lot of other niceties, though.

Cdc2,
As is always the situation, execution of design is at least as important as the design itself.
Good Question!

Trelja...Not only "to each his own" but "to each kind of music its own". I agree that for heavy duty organ music, and the like, Klipshorns will beat out any electrostatics. And for a solo violin piece, my little B&W monitors are great.

We're on the same page, Eldartford.

One thing I now remember Bud recently telling me involves the superiority of the TL over the sealed/aperiodic alignment. As many know, the Fried C satellite (often used with D 8" or O 10" subwoofer in the Valhalla system) was originally an aperiodic design, but when they began manfacturing the Model Q, which had also loaded the midrange in a transmission line, their flagship speaker was now inferior to the next model down. It made that much of a difference, as the TL midrange is even more important than a TL woofer.

Obviously, the focus of development switched to bringing the C satellite inline. Thus, the C3L/C4 was born.

It was SO much better that Bud used to demo them at shows and get togethers against the same speaker, aperiodically loaded. He says that people would often get quite overheated, swearing that he must be using different drivers or crossovers in the two speakers. But, he was not. The TL on its own was just very much better.

Sean, thanks for the detailed description of your setup. It sounds absolutely fascinating.

I certainly agree about TL being the best way to deal with the back wave if you are going to build a vented design--that is, for all the little I know about it. I was too ignorant and ill-equipped to try designing a TL or even a good reflex in my own first try so I opted for what G.A. Briggs called a distributed port (DP), in his "Cabinet Handbook" from 1955. This is close to an aperiodic--basically you calculated your port area for the bass resonance of the system and divided it up into ten or so slots, damped with felt. Great DIY design, very forgiving, lower Q made it less critical to hit the system resonance right on in the port and box volume calculations. Well below your league.

Reading Briggs' book you got the feeling he was a bit wistful about the infinite baffle. He didn't talk about it much but he liked it. Maybe it was because as a company, Wharfedale could never have sold more than drivers for the design. I bet he would have liked your setup.

I love the variety of enclosure designs. Almost as many as there are for tube amps in Japan. I once saw one for a very short TL ending in a ported box which was said to get great bass out of a 4 or 5-inch paper woofer.