For my wood shop summative, I've decided to make some DIY bookshelf speakers. Normally, MDF would be use, but to cut that during class time would require having respirators and goggles for all 24 guys. So no MDF.
BUT I have scrounged up some 3/4" Baltic Birch/Russian Plywood as a substitute, which will get here on Monday. I plan to duplicate a set of
Zaph's Bargain Mini's, although with a few tweaks of my own.
1) Recess the baffle into the 4 sides
2) Do a 3/4" roundover on the front of the sides
3) Have a recessed back
Preliminary side sketch:
Front drawing (from Zaph's page):
Baffle detail (also from Zaph's page):
Dimensions are 9 1/4" deep, 10" tall, and 6 1/4" wide
Crossover Components:
-2x Bennic wirewound 4ohm resistors
-2x Bennic wirewound 5ohm resistors
-2x 10uF Solen/SCR/Bennic/Clarity Caps Poly capacitors
-2x 2.7uF Solen/SCR/Bennic/Clarity Caps Poly capacitors
-2x 3.3uF Solen/SCR/Bennic/Clarity Caps Poly capacitors
-2x 1.5mH Solen/other brand 18-20ga inductors
-2x 0.25mH (or close to) Solen/other brand 18-20ga inductors
-2x 0.1mH Solen/other brand 18-20ga inductors
-Speaker wire as ICs between the Xover & woofers/tweeters/binding posts
-63/37 0.20-0.32" dia. solder
Vendors: Solen, Madisound, PartsExpress, any other reliable DIY place
Cabinet Parts:
-5' x 5' 3/4" Baltic Birch/Russian Plywood (this is the size it comes in, you only need half of that for a pair, with lots to spare)
-1" dia. x 4" Port tube (I couldn't find any 1" dia. PVC tubing at Home Depot or Rona, so I had to buy special port tubes)
-2x MCM 4'' Shielded Aluminum Cone Woofer (
Part #: 55-1853)
***Remember to get the source code on the flyer (
here), as it'll get you a discount (only if the woofer is on sale)***
-2x Aurasound NT1-204-8D 3/4" Titanium Dome Tweeter
***DO NOT TOUCH THE DOME***
It is out of stock with a lead time of at least 4 weeks, a substitute (same size & mounting method), BUT IT IS NOT RECOMMENDED, is below
-2x Dayton ND20FB-4 Rear-Mount 3/4" Neodymium Dome Tweeter
-1/2" Sonic Barrier Dampening
-1 1/4" Sonic Barrier Dampening
OR
-1/2" Chopped foam carpet padding doubled (or tripled) up
***To judge whether chopped foam is good or not, hold it up to the light. There shouldn't be many pinpricks of light shining through. This type of material is pretty much the only cost-effective damping material for speakers. It's really not that bad.***
-5/16" OR 1/4", 1 1/2" long socket cap screws (black)
-5/16" OR 1/4" Tee nuts
-4x Binding posts
-Various sizes of heatshrink
LOG
March 10, 2008
-Ordered parts
March 15, 2008
-Some parts arrived :rock::
March 17, 2008
-My plywood arrived, except it was the wrong thickness...
March 18, 2008
-Some crappy pics of my workspace:
March 19, 2008
-PE order arrived, along with my wood!
Hmmm, whats in the PE box?...
Some books and...
MY TWEETERS...
Close-up of the protective cap & tweeter
Along with my 18mm (sigh...they don't make it exactly 3/4") Baltic Birch
Dramatic angle shot showing all 13 plies
March 26, 2008
-My Mini-RCA IC parts arrived (Canare Star-Quad, Switchcraft connectors)
March 27, 2008
-IC done (Canare StarQuad, Switchcraft connectors), Mini-RCA:
March 28, 2008
-My woofers arrived and I began cutting the wood to width
March 29, 2008
-The last of my parts arrived, some perfect lay inductors and wirewound resistors from Solen
-Soldered all the wires to the woofer and tweeter, all preliminary work done, have to wait until enclosure is done
Brendan