The Ariel seeks the elusive middle ground between low-efficiency audiophile speakers and refrigerator-sized high-efficiency horn systems, using twin transmission-line bass loading to get the deepest bass and clearest midrange. But I'd be the first to admit it's a challenging speaker to build - so I created a companion speaker, the ME2, which is more compact and a lot easier to construct. The ME2 uses the same overall design principles as the Ariel, it just sacrifices a bit of midrange clarity and bass depth. On the other hand, it works a lot better in smaller rooms, where the Ariel can sound bass-heavy due to floor coupling of the vent.

Over the last ten years both designs have evolved and grown in response to feedback from enthusiast builders all over the world. (See the Ariel Builder's Club for pictures and comments from readers.) Then again, maybe you just want to read about what goes into high-end speaker design. Whatever your interest, you'll want to warm up the printer and read the Web page at your leisure. (Printer and modem-friendly; no cookies, Javascript, ActiveX, or PDF files anywhere, just text, HTML, and pictures. Old-fashioned but effective.)

The Ariel and ME2 page is hosted by Nutshell High Fidelity, which features the Danish Audio ConnecT product line, articles about triode electronics (see Amity, Raven, and Aurora) and the Soul of Sound Library.

These are models that people are building right now; the Mark 6 is the Nutshell High Fidelity production version. If you're curious about previous models of the Ariel, or are in the middle of building a pair, please visit the History of the Ariel page.

The pictures are 144dpi GIF files, and are designed for printing at 50% reduction (a one-step procedure on the Macintosh). If you are using Windows, it's a little more complicated. Right-click the mouse while pointing at the picture. A window will pop-up and ask what you want to do; select "Save As ..." and give the picture a name. You can then "Insert" the saved GIF file into MS Word as a picture file; alternatively, it can be opened in the public-domain LView program or any other graphics program. Either way, the 144dpi GIF image will print at high resolution as a one-page vertical-format picture.

Note: Builders using the metric system should physically measure the speaker drivers instead of converting the fractional inches shown on this diagram. When converting enclosure dimensions to the metric system, start from the interior measurements first ... all other measurements are keyed to the interior dimensions. For example, the rear panel thickness is shown in the drawing as 3/4", but 1", 1.25", or 1.5" would be acceptable, even desirable ... just keep the interior dimensions the same.

Detailed Construction Plans for the ME2

28K, 984 x 789 GIF. Print portrait at 50% reduction. The little brother of the Ariel, with the same drivers and crossover. Simpler cabinet, 20Hz less bass. Midrange is slightly different than the Ariel as a result of smaller interior dimensions and minor vent resonances that occur in all vented-box enclosures. For smaller rooms, especially ones with low ceilings, the ME2's are very likely a better choice than a full-size speaker. What would otherwise be somewhat limited bass in a large room will be nicely filled out in a small room.

2-meter, Nearfield, and 1/3 octave In-Room Frequency Response

18K, 723 x 561 GIF. Print landscape at 75% reduction. The two MLSSA frequency-response graphs are comparable to the graphs published in mass-circulation audio magazines. The upper graph shows the anechoic first-arrival frequency response of the Ariel (the most common type of FR graph), and the lower graph shows a FFT equivalent to a 1/3 octave Real-Time Analyzer (RTA) room response measurement (FFT averaged over 1 second).

MLSSA Impulse and Frequency Response with 6mSec Window

24K, 613 x 1167 GIF. Print portrait at 50% reduction. The MLSSA time, frequency, and 3-D cumulative waterfall responses are comparable to the graphs published in the mass-circulation magazines. These are useful for assessing the time-domain response of a speaker, and the presence of any resonances in the 500Hz to 20kHz region.

MLSSA Impulse and Frequency Response with 2mSec Window

19K, 591 x 1164 GIF. Print portrait at 50% reduction. Shorter window, prettier measurements. Included here just to show how much nicer things get when the window-size is reduced (although part of the improvement is the elimination of a -20dB floor reflection at the 9 mSec marker, just barely visible in the previous impulse response graph).

Ariel and ME2 Crossover & Impedance Correction Network

8K, 488 x 555 GIF. Print portrait at 100%. Not a minimalist crossover, sorry, but the one that sounded the best. This is actually Version 15 ... yes, I built, measured, and auditioned 14 other versions, starting with a minimalist 1-cap, 1-resistor crossover first.

Milestones in Audio (from Soul of Sound book)

39K, 1216 x 1026 GIF. Print landscape at 50% reduction. This large illustration shows the significant developments in audio from 1920 to 2000.

Family Tree of Audio (from Soul of Sound book)

39K, 1218 x 1002 GIF. Print landscape at 50% reduction. This illustration shows the influences that movie sound, the mass-market, high-fidelity, and the ultra-fi movement have had on each other from 1920 to 2000.

Credits



© Lynn Olson from 1995 through 2003. Permission is granted to Webmasters, readers, and any others to link and mirror these HTML files, along with the associated image files. If you'd like to borrow an image or portions of text from this site, please include a credit and a link back to http://www.nutshellhifi.com/. Although internal links continue to work, they may change in the future as new material is added to the Website.