Enigma 44 – 2.5 Way Transmission Line System
Design and Constructed By:
Kevin Shawbitz
Design Goals
- Accurate response
- Utilize a transmission line
- Excellent bass extension
- Be pleasant to listen to
- Costs $950 including stands
- Work in a variety of rooms
Key Features
- Large size (LxWxH= 8.25″x18″x38.25″)
- F3 of 44 Hz when near a wall
- ±2dB response
- Clean, articulate bass
- Costs $950
Drivers
- SEAS Prestige CA15RLY (H1216) 5.5″ Coated Paper Cone Woofer
- ScanSpeak Discovery D2608/9130 1″ Textile Dome HDS Tweeter
Frequency Response
Impulse Response
PA 2201 Midfields
Design By:
Thomas Conran
Key Features
- Medium size (LxWxH= 27″x9″x15″)
- F3 of 56Hz
- +/- 2dB response
- Tight, accurate sound
Drivers
- SB Acoustics SB23NRXS45-8 woofer
- Tang Band 75-1558SE midrange
- Fountek NeoCD 2.0
Frequency Response
Intergrated Frequency Response
Design Statment for PA 2201 Midfields
Griff ’91
Design and Constructed By:
Collin Doerr-Newton
Design Goals
- Portability
- Accurate response
- Good bass extension
- Be pleasant to listen to
- Under $700
Key Features
- Medium size (LxWxH= 16″x12″x20″)
- F3 of about 50Hz
- +/- 2dB response
- Big open sound
- Well under $700
Drivers
- SBAcoustics SB17NRXC35-8 woofer
- Vifa XT25TG30-04 tweeter
Chosen Testing Results
Integrated Frequency Response
Red- Overall Response, Purple- Woofer Response,
Green- Tweeter Response
Horizontal Off-Axis Response
Red- 0 degrees, Yellow- 15 degrees, Purple- 30 degrees, Red (2)- 45 degrees, Green- 60 degrees
Documentation
The Krakens – 3-Way Sealed System
Designed by Renata Putzig
Design Goals
- Large Soundfield
- Low fatigue
- Accurate transients
- For casual listening and movies
- Aesthetically pleasing
Key Features
- +/-2 dB from 70Hz to 20 kHz
- F3 of 50Hz
- Solid cherry
- Sealed box
- Ribbon tweeter
- 14 3/4″ x 24 3/4″ x 21 3/4″
- Cost: ~$1000
Drivers
- SB Acoustics SB23NRXS45 8″
- Seas Prestige MCA12RC H1304 4.5″
- Fountek NeoX 2.0 Ribbon Tweeter
Euphony Blues
Design and Construction by Lindsey L. Johns.
Design Goals:
- Accurate frequency response: at least +/- 3 dB, preferably +/- 1.5 dB, low distortion
- Accurate bass response down to at least 60 dB
- Smallest possible size for shelf or desk placement
- Sturdy and unique-looking cabinet
- Budget under $600
Results:
- +/- 1.5 dB between 55 Hz and 18 kHz, less than 1% harmonic distortion over 50 Hz
- f3 of 50 Hz
- Dimensions: 14″ wide, 19″ tall, 14″ deep
- Very sturdy cabinet with custom glossy indigo finish
- Cost roughly $500
Drivers:
Dayton Audio RS225-8 8” Aluminum Reference Woofer
Dayton Audio RS28F-4 1-1/8” Silk Dome Tweeter
Testing Results:
Documentation:
Design Statement and Tuning Report
(Note: Some documents labeled by the previous working title, “Baby Blues”)
Raving Behemoths
Designed, Built, and Tested by Nathan Hunter
Design Goals
- High Output
- improved Horizontal Off-Axis Response
- Low Frequency Extension with ƒ3 ≈ 50 Hz
- Voicing to include Bass Boost
- Low cost comparing to PA Speakers with similar capabilities
Features and Components
- Diamond Shape with Rugged Exterior
- Floor Mounting
- Active Digital Crossover PCS 2.400
- Selenium Pro D220Ti Horn Driver
- Selenium Pro HC23-25 Exponential Waveguide
- 2x Dayton Audio PA301-8 12″ Woofers
- Carvin Cabinet Handles for easier mobility
Weight Vs. Similar Products
- Raving Behemoths ≈ 150 lbs
- JBL PRX612M = 34.5 lbs
- QSC KW122 = 49 lbs
Cost Vs. Similar Products
- Raving Behemoths ≈ $1300
- JBL PRX612M List Price = $1299
- QSC KW122 List Price = $1399
Testing Results
Documentation
The Chickenfeet
Design Goals
- Sealed box
- Tight low bass response
- Easy to transport
- Good off-axis
- Unique paint job
- For listening and mixing
Features
- Diffusion panel inside of box
- Great off-axis response
- Dimensions 19.25″ x 10.5 x 21″
- Cool paint job
Ignis Series 1
Designed, Built, and Tuned by Jonathan Moths
Design Goals:
- Small size for desktop use
- Low cost ($400-500)
- Primary use is listening for pleasure
- Maximize bass extension despite small size
Features:
- 1″ diameter side port to enhance bass extension
- Portability and small size (9 1/2″ x 9 1/4″ x 1’2″)
- +/- 2 dB from 70 Hz to 20 KHz
- F3 of 60 Hz
- Metal Dome Tweeter
Drivers:
- SB Acoustics SB26ADC-C000-4 Metal Dome Tweeter
- SB Acoustics SBMFC35-4 6 inch Poly Cone Woofer
Documentation:
MonoChromes
//Features.
- Vented box
- Bookshelf speakers only 10″ x 14″ x 14″
- 1.5 inch thick MDF exterior
- 2nd Order Crossover
- Cost Efficient (around $260 as they are, about $320 with final crossover)
//Materials.
- Box is made solely out of two layers of 3/4″ MDF
- Banana terminals
- Adjustable port
//Drivers.
- Woofer: Dayton Audio DS175-8 6-1/2″ Designer Series Woofer
- Tweeter: Dayton Audio RS28F-4 1-1/8″ Silk Dome Tweeter
//Tweeter Response
//Woofer Response
//Response Combined
arbor.
DESIGN + CONSTRUCTION.
Chelsea Leighton
GOALS.
+Bookshelf size for small-room use
+Flat frequency response
+Solid transient handling
+Relatively low frequency extension
+Stable, accurate stereo image
+Within $800.00 budget
DRIVERS.
+Tweeter: Seas Prestige 27TDFNC/GW
+Woofer: Vifa P17WJ-00-08
MATERIALS.
+Inner Box: 3/4″ European Birch, 13-ply
+Mechanical Dampener: 1/8″ Loaded Vinyl
+Outer Box: 1/2″ Rotary Red Oak
DOCUMENTS.
+CONSTRUCTION IMAGES
+DESIGN STATEMENT
+DRAFTING
+GLOSSY
+TESTING & TUNING REPORT
TESTING RESULTS.
Frequency response of overall system (blue), tweeter (purple), woofer (yellow), and corrected port (red).
Step response of the entire loudspeaker system with crossover.
arbor. by Chelsea Leighton is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
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