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"The
V-D Monitor"
2-Way Vifa-Dayton
Monitors
Project, Text and
Images courtesy of Dave
Tenney
"After
finishing my first set of DIY speakers (The
D3's), I had the overwhelming urge to build another set of speakers. I
had purchased an extra set of Dayton Silk Dome Tweeters on the deal of the
day, and as luck would have it the Vifa P17WJ-008's followed suit a few
months after..."
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Overview
Now all I needed was a crossover.
Having limited experience with crossover design, I was a bit
apprehensive about wasting a lot of money experimenting on my second
DIY attempt. I guess lady luck was on my side for this project,
because Wayne Jaeske of SpeakerBuilder.net
fame had posted a suggested crossover design.
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Drivers
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Vifa P17WJ-00-08 6.5" Cast Frame Woofer
PE Part Number 297-305
Ideal for
mid-sized bass reflex designs, this is Vifa's most popular woofer. It
utilizes a cast magnesium basket, rubber surround, mineral filled
polypropylene cone, and very smooth frequency response. Intended for
use with vented enclosures with .35 to 1.00 cu. ft. of internal
volume.
Full
Specifications
Download Spec Sheet (379k pdf)
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Dayton 1-1/8"
Silk Dome Tweeter
PE Part Number 275-070
Clinically tested
and compared to Morel with amazingly similar results, this tweeter is
recommended for crossover points as low as 1800 Hz. That versatility,
along with its high performance to cost ratio, makes this one of the
most popular Dayton drivers.
Full
Specifications
Download Response Graphs (17K PDF)
Product
Review By Wayne Jaeschke
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Cabinet Design
The next thing I needed to
tackle was a proper enclosure design. After researching different designs (especially
this one), I decided I would need a cabinet with an internal volume of
around 17L tuned to 45Hz. I used the calculators on Loud
Speakers 101 to do all of my calculations.
 Click
here to see the enclosure schematic with measurements.
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The enclosure is pretty basic. It is
a 17L box with internal dimensions of 7"W x 10"D x
15"H. It has one brace in the middle which measures 4" x
7". The port is made from a 2" ID x 5.5" PVC pipe
located 3" from the top of the box. All of the drivers are flush
mounted. I use a 1/2" rabbit bit in a router to do this. The port
is glued in, and all joints are sealed with white bathroom caulk.
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Building the crossover
Building your own crossover is a
pretty easy task, all you need is soldering iron, some solder, and the ability
to read simple schematics. The way that I assemble a crossover is to lay out
all the components on a newspaper and twist the appropriate components
together. Then I glob on a ton of solder. I do not use any jumper wires when I
build crossovers. I will readily admit my circuits are very ugly!
You will notice in the parts
listing that there isn't a 9 ohm resister listed. I substituted the 8 ohm in
place of it...I seriously doubt that anyone could hear a 1 ohm difference
between the two values in a zobel network.
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Installing the
crossover
I wouldn't recommend my
method of installing crossovers, but it does work and it's cheap. I take
a tube of two part epoxy, smear it all over the bottoms of all the
components, stick them on the back of the enclosure, and pray I have
them wired right. A lot of people use hot glue to install crossovers,
but I always have a fear that one of the glue joints will come loose and
cause a rattle inside the cabinet. |
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Crossover Courtesy of Wayne
Jaeske
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Testing
After I have the crossovers
assembled, I tape the front baffle and speaker on the enclosures with
masking tape so I can give them a test listen. This gives me a chance
to see if I've got everything wired up right, and kind of gives a
sneak preview of what the speakers will sound like. I was impressed!
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Cabinet
Assembly
My personal method of
cabinet assembly is to use glue only. I like to use either Titebond or
Elmer's carpenter glue. I assemble the sides and rear baffle first,
install the crossovers on the rear baffle, line the sides of the
cabinet with egg crate foam, and then glue on the front baffle. In
final listening tests I used about two ounces of poly fill behind the
woofer.
Veneering the cabinet is
also pretty easy. The veneer is secured with contact adhesive, and
trimmed with a flush trim bit in a router. I stained them with two
coats of Olympic America Cherry stain, and six coats of Minwax satin
polyurethane lightly sanding with 320 grit paper in between the first
two coats, and steel wool for the last four.
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Auditioning the Finished
Speakers
The only thing that I have to
reference these to are my D3's. The VD's are a bit bass shy, but this is a
noted characteristic of the P17's. This is not to say they don't have a good
low end, they just don't seem to go as low as the Dayton drivers. This might
also have something to do with the D3's having dual woofers. Where these
speakers really shine is the midrange. It is more detailed and pronounced
than the D3's. You can really hear the guitar or bass player's fingers on
the strings, snare drums really pop out of the mix. The high end is very
good also...a bit more laid back than the D3's, but very easy on the ears.
You can always tweak the treble knob if you want to split hairs. This is my
first experience with European drivers and I am quit impressed. I do feel
that this design would make an excellent studio monitor. Overall I'm very
happy with the way this project sounds, and at the price it costs to build a
pair you would be hard pressed to find a commercial speaker of similar
quality.
Burnin' em up with the old H-K!
Parts Express Ordering List
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SKU
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Item
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Qty.
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Price
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Ext. Price
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027-410
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DAYTON 1.0uF-250V
POLYPROPYLENE
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2
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$1.15
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$2.30
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027-424
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DAYTON 6.8uF-250V
POLYPROPYLENE
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2
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$2.25
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$4.50
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027-432
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DAYTON 15uF-250V
POLYPROPYLENE
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2
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$4.10
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$8.20
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260-302
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GOLD PLATED SPEAKER
TERMINAL
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2
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$1.99
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$3.98
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266-355
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1.2mH 14 GA. PERFECT
LAYER INDU.
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2
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$13.13
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$26.26
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266-814
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.40mH 18 GA PERFECT
LAYER INDU.
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2
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$3.40
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$6.80
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275-070
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DAYTON 1-1/8" SILK
DOME TWEETER
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2
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$15.50
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$31.00
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297-305
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VIFA P17WJ-00
6-1/2" WOOFER
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2
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$37.90
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$75.80
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005-8
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MILLS 8 OHM 12W
NON-INDUCTIVE
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2
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$3.50
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$7.00
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005-3
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MILLS 3 OHM 12W
NON-INDUCTIVE
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2
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$3.50
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$7.00
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027-419
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DAYTON 4.3uF-250V
POLYPROPYLENE
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2
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$1.86
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$3.72
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Subtotal:
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$176.56
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Cabinet Materials
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Supplier
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Item
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Qty.
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Price
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Ext. Price
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84 Lumber
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4x8
sheet MDF |
1
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$19.00 |
$19.00
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Lowes
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24x48 Red Oak Veneer
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1
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$25.00 |
$25.00 |
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Lowes
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12x48 Red Oak Veneer
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1
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$14.00 |
$14.00 |
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Lowes
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Silicone Caulk
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1
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2.00 |
2.00 |
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K-Mart
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Egg-Crate Foam
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1
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$4.00 |
$4.00 |
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Dollar Store
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Polly Fill
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1
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2.00 |
2.00 |
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K-Mart
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2 Part Epoxy
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1
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$3.49 |
$3.49 |
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Subtotal:
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$69.49 |
Total Project Cost: $246.05
About the Designer
Dave Tenney
"I am a SWM lookng for high SPL via
DYI. I have an AAS in Network Technology from The University of Akron, and
am currently pursuing a BS in Tech. Ed. By
day I am the Technology Coordinator at a medium sized library. By night I
play bass with various shady characters in dirty bars and build speakers...
that is when I'm not studying, of course!"
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