This will be a fun build!!!

Hi Guys.

So, a follow member (Bumbledad) gifted me a new pair of Heil AMT drivers. I decided to build a pair of speakers with parts I have in the shop.

I have a pair of JBL 6x6 horns and a pair of Dayton Audio DT250P-8 Compression Driver.

I also have a pair of DynaLab V22-DR-0003 8" Paper Cone Woofer 4 Ohm that have an f3 of 25hz in a 3 cu ft box.

The CD is solid down to 600hz out to 10khz.

so I want to cross the woofer at 600hz to the CD then cross the CD at 5khz or so to the Heils. I have an active three-way crossover and a handful of amps.

Below is a link to the woofers and a picture of what I’m thinking for the cabs but with the horn above the woofer and the Heils on top like the picture.

DynaLab V22-DR-0003 8" Paper Cone Woofer 4 Ohm



IMG_3759.jpeg

IMG_3761.jpeg
 
Last edited:
I’m not sure how accurate the Parts Express cabinet size recommendations are but it’s a starting point.


Parts Express Staff Recommended Enclosure Volume​

Sealed Volume0.682ft³
Sealed F364.72Hz
Vented Volume2.98ft³
Vented F325.51Hz
 
So, is there a reason to use a folded Voigt pipe it transmission line for the woofer cabinet??? Here are the speaker specs.

Product Details​

BrandFactory Buyouts
ModelV-22DR-0003
Part Number299-4004
UPC844632014871
Unit of MeasureEach
Weight3.45

Product Specifications​

Nominal Diameter8"
Power Handling (RMS)80 Watts
Impedance
Frequency Response40 to 4,500Hz
Sensitivity86.98dB 2.83V/1m
Voice Coil Diameter1.5"

Thiele-Small Parameters​

Resonant Frequency (Fs)53.16Hz
DC Resistance (Re)3.16Ω
Voice Coil Inductance (Le)0.292mH
Mechanical Q (Qms)4.548
Electromagnetic Q (Qes)0.9746
Total Q (Qts)0.8026
Compliance Equivalent Volume (Vas)0.7393ft³
Mechanical Compliance of Suspension (Cms)0.325mm/N
BL Product (BL)5.46T·m
Diaphragm Mass Inc. Airload (Mms)27.559g
Maximum Linear Excursion (Xmax)5mm
Surface Area of Cone (Sd)248.16cm²

Materials of Construction​

Cone MaterialPaper
Surround MaterialRubber
Voice Coil Wire MaterialCopper
Voice Coil FormerAluminum
Basket / Frame MaterialSteel
Magnet MaterialFerrite

Mounting Information​

Overall Outside Diameter8.75"
Baffle Cutout Diameter7.25"
Depth3.25"
# Mounting Holes4

Parts Express Staff Recommended Enclosure Volume​

Sealed Volume0.682ft³
Sealed F364.72Hz
Vented Volume2.98ft³
Vented F325.51Hz
 
Last edited by a moderator:
I also came across this post from 2007 from philthien on Tech Talk.

Fried made several versions of Beta speakers, and one of them used two smaller holes (maybe 1/2") in the baffle as aperiodic vents. I imagine the backs of the holes was covered with some material. But I guess you don't have to worry about port noise so you don't need to go overboard on size. I have heard Beta speakers and was amazed by the bass coming from such a small package.

I'm including a pic.

IMG_3775.jpeg
 
Last edited:
This will be in interesting experiment.

From the P.E. Site they recommend—-
Sealed Volume of 0.682ft³
Sealed F3 of 64.72Hz
And
Vented Volume of 2.98ft³
Vented F3 of 25.51Hz

So where would an Aperiodic Vented cabinet end up for volume and F3???

And, how do I determine the volume?
 
frugal-phile™
Joined 2001
Paid Member
Fried made a bunck of aperiodic loudspeakers. The R & The Q were standout. Essentially a box with a substantial slot vent filled with foam rubber (i think they could have used better, looked like it could have been a slice from a foam mattress).

1173161-19f42dc4-imf-bud-fried-model-r-ii-speakers-rare-vintage.jpg


Never saw a Q with such nice veneer, the ones we had were cosmetically similar to the bigger R.

FriedQ.jpeg


dave
 
frugal-phile™
Joined 2001
Paid Member
Gotta go turn on my modeling computer.

The Qt is high. Hgher than the max flat Q = 0.707. Any box will push that higher.

An aperidoci box (a controlled leakage sealed box) will lower the Q somewhat.

So the reciepe is, a box as large as you can live with and make it aperiodic.

Or sealed, with EQ (Linkwitz transformish thing), but requires extra power & excursion.