Are Lowthers a "full range listening" speaker?

Thanks TWL for such a thorough answer! This looks to be a great forum and site in general. The descriptions of the "immediacy" of the Lowther sound really pique my curiosity. Coherency as well. Though I must admit I like to "modulate the walls" occasionally, I really only enjoy volume when it is very clean, and not continually. Musicality matters more!
Where are plans for the Voight Pipes with modifications available from, or were they your own experiments? Do you recommend a driver that is compatible with the Pipes?

There are no plans available for my mods, but the basic design came from the Lowther Club of Norway design, and that is the best one I know of. To improve wave-launch, and handle the baffle-step problem, I added 12" wide "swinging doors" to each side of the enclosure, which provides acoustical reinforcement using the 1/8th-wave formula down to about 48Hz. Of course the majority of radiation at that frequency and below is out the bottom port, so floor boundary reinforcement picks up to bolster the rest of the way down to the 40Hz lower limit. This eliminated the need for an electronic baffle-step compensating network that would have cut effeciency by 5db, and obstructed the signal path. So instead, I reinforced the freq's below the baffle step point, acoustically, thus retaining efficiency and pure signal path. The "swinging doors" allow them to be angled to the rear, to keep them out of the diffraction plane, and still do their job. It also allows adjustment of the reinforcement, so I can tailor the response to individual recordings as needed, by adjusting the backward angle. This is all just a simple application of known technology, and it works. The trade-off is larger size of the speaker enclosure, and they are quite large in frontal area.

The driver I selected was the new series Lowther EX3, which worked very well in this application. This system provides good bass within its design parameters, but it is not a system for "bass freaks". If you want the "boom boom" then add a subwoofer. Most people who are "bass freaks" will only notice the deeper, more powerful bass, and probably wont't even notice the seams, or phase-shifting, or speed differential non-matching that is introduced. This is because they have always had multi-drivers and this was present in all their previous speakers, so they don't notice any difference. You only notice it, when you started from a single-driver perspective, and then tried to add the bottom end.

This is not a system for everyone. It has ultra-revealing qualities that will let you know everything about what is wrong with your system. In my opinion, transistor amps are not suitable. Only a high quality SET amp using 300B or under, like 2A3 or 45, is correct in this setup. Push-pulls will be revealed as push-pulls. Hums, noises, hash, distortion, record noise, all will be coming right out your speaker if you have any of these noises. Components must be musical and quiet. This means good tube components and great tube selection. Cables, connectors, vibration control products, and everything can be heard easily, and may require some changes. In the end, it will do certain things better than any other system can, and it will have its weaknesses also. It is up to you to decide if this presentation is what you want out of your system.

Hello Everyone,
I have been very persuaded by various comments here on Audiogon that the Lowther driver is the way to go. Has anyone compared the Voigt pipes to any of the other options such as the enclosure designed by Jena Labs? TWL's comments would be very appreciated, since I regard him as our resident expert in these areas. For those of us who will have to have a cabinet maker build these for us, the cost is probably similar for each of the options. Also, how large are the enclosures such as the Voigts? Thanks for such a great thread
Dennis

Hi Dennis. The Jena labs cabinet designs are some of the relatively newer designs on the Lowther market. The Medallion 2 is sort of like a Lammhorn design, and is good to about 60Hz on the bottom end. True horn designs, whether they be front or rear loaded, are limited by the length, shape, and size of the horn cavity, especially the mouth dimensions. Very low response is generally not achieved by true horns due to overall size considerations that are required for deep bass horns. I have looked at the Medallion 2 cabinet, and it looks like a pretty solid design, and should be quite satisfactory within its design parameters. The Voigt Pipe has a lower cutoff frequency because if its combination design not being a true horn. The transmission line and bass reflex characteristics allow deeper bottom end than most non-corner horn designs for the Lowther. Voigt Pipes are the cheapest and easiest to make, and are probably not the very best enclosure for the Lowther, but they are good. Some commercial designs like the Lammhorn 1.8 or Rethm systems will do better than the Voigt Pipe, but cost far more. I have found that the Voigt Pipes were fine for me, at the money I could spend. The sound is much better than would be expected from something that costs as little as it does. Mine were only about $1500 total including drivers, solid oak cabinets, and hardware. Took about a weekend to build using only a circular saw, jigsaw, hand drill, screwdriver, and glue. I used cabinet grade lumber, so finish sanding and staining was simple. The normal Voigt Pipe(non-folded) is 6 feet tall and has a 1 foot square footprint. Mine have extended sides that are hinged, and protrude out 1 foot on each side, for a total width of 3 feet when the "wings" are fully extended. So a normal Voigt Pipe will be 6' tall and a foot wide, and mine are 6' tall and 3 feet wide. Both are a foot deep. Lowther drivers take a very long time to break-in, and will need at least 100 hours to start "loosening up" and giving better bass. After 500 hours, they are fully broken in. They sound great from the beginning, but get alot better. I think the Hedlund horn is a very nice cabinet, but complex to build. If I had some money and time, I would give them a try myself. But I am quite happy with the Voigt Pipe, even if they are not the "ultimate" design. They will give you plenty of enjoyment and music at reasonable costs. When you read about the Voigt Pipe design, alot of disparaging comments are made about the "comb-filtering" problem, but that never was a problem for me. I think that too much is made of that, and is not really the problem that they make it out to be. If there is a problem with that, it is not noticeable in actual listening, so I don't consider it a problem in real world use. Welcome to the world of single-drivers.

I recently converted to an AER rear-loaded horn speaker (102db). I believe I am getting very good bass down to 40Hz. I also use an Art of Sound Tycus subwoofer to reinforce the bottom end. It is a very quick subwoofer that blends in very well. I have heard a Lowther DX3 speaker that I sounded good but the AER is much smoother. I am using an AER MKII-SP which is especially made to improve the bass in the enclosure I am using. Go to http://www.fullrange-speakers.com/1version/eng/home-e.htm to view the Acoustique speaker which I am using. The AER MKII-SP is around $2500. The sound is very detailed, dynamic, and imaging very three dimensional. Full Range Speakers will provide the plans for the cabinets.
Good luck - lots of choices and lots of info on the web.