Built a "luggable" boombox.

[[Image(http://ohm.bu.edu/~hazen/TubeAmp/BoomBox/on_bench_unpainted_sm.jpg)]]

See http://ohm.bu.edu/~hazen/TubeAmp/#boombox

Used two 6T9 "compactron" tubes in Ultra-linear single-ended configuration, closely following this excellent design:

* http://diyaudioprojects.blogspot.com/2008/09/ultra-linear-6t9-diy-tube-amplifier.html

Other parts:

* Antek AS-05TC250 power transf for $35.00. 250-0-250, 6.3V, 5V 50VA total
 * http://edf.bu.edu/svn/edf/EricHome/TubeAmp/BoomBox/AnTek_AS-05TC250.png
* 12 pin tube sockets
* Pair of 6T9s
* FaitalPRO 3FE25 ([https://www.parts-express.com/faitalpro-3fe25-3-professional-full-range-woofer-8-ohm--294-1104 link]) $20 each / 
 * .12 ft3 = 207 in3 / port 1" dia x 3" long

See also:

* https://www.nutsvolts.com/magazine/article/the_stereo_6t9
* http://diyaudioprojects.com/Tubes/6T9-Tube-Amp-Kit/

Boxology-

* Speakers: 5.5w x 7d x 8.7h (outer) box of 1/2" plywood.  
* One port 1" ID 3" long
* Two-layer chassis with two "floors" 6w x 8d x 9h.
* Speakers hook on side of chassis with carrying handle
* [http://ohm.bu.edu/~hazen/TubeAmp/BoomBox/FRONT_MECH%20Model%20(1).pdf Drawing] of proposed layout

Plywood cutting from 18" x 8' piece for speakers:

[[Image(http://edf.bu.edu/svn/edf/EricHome/TubeAmp/BoomBox/plywood.png)]]

Other