
AUTOTEK
STREET MACHINE SERIES
CAR AUDIO SUBWOOFERS
Congratulations on your purchase of the new Autotek Street 
Machine Series subwoofer system. The Street Machine subwoofer 
series offer incredible output, great sound quality and outstanding 
good looks.
12-Inch DVC / SVC Subwoofer 
Dual 4-Ohm + 4-Ohm Voice-Coil / Single 4-Ohm 
High Energy Magnet 
Polypropylene Cone 
Poly-Mica Cone Damping 
Multi-Layer High-Temp VC 
Poly Light Dust Cap 
Front-Plate & Voice-Coil Cooling 
Integrated Spider Tinsel-Lead Design 
Hi-Excursion Surround 
Anti-Resonant Magnet Boot
As with all high quality car audio products, we recommend 
professional installation by an authorised Autotek dealer. 
Your dealers knowledge and experience can ensure a problem free 
and cosmetically integrated installation. 
If you choose to install the subwoofers yourself, please read the 
entire manual very carefully.
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SUBWOOFER INSTALLATION AND WIRING DIRECTIONS
Enclosure Materials
Typically, 5/8” or 3/4” MDF (Medium Density Fiber Board) is best 
for most applications. 3/4” MDF is recommended.
Enclosure Build Materials 
Connecting joints need to be glued and screwed to ensure no 
air escapes and joints do not separate under high pressure. 
Mitered and rabbit joints also help to ensure the enclosure joints 
are secure.
Bracing
Internal bracing is also recommended to prevent flexing and to 
strengthen the enclosure. 
Note: The volume taken up by the bracing should be added to the 
total enclosure interior volume. 
There are two common bracing methods.
1. Corner Bracing: These help prevent the connection joints 
from separating under heavy vibration and air pressure. 
Use 1’ x 1” MDF at all interior joints
2. Diagonal Bracing: These internal braces connect the top side 
to the bottom side as well front side to back side. This prevents 
the wood from bowing or pushing outwards. 
Use 1” x 2” with 1” surface contact that is glued and screwed.
Wiring
Wiring Parallel, Series or Parallel/Series will affect the final 
impedance at the amp and great care must taken to ensure the 
amp is not driven below it’s intended impedance capabilities.
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NOTE: All above box volumes are internal values and already include subwoofer and port 
displacement. The F3 value represents the -3dB cut off of the enclosure in Hz. Polyfill may 
be added to sealed enclosures to reach desired Q-Value.
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Glossary of Terms
Q    The energy losses of relative damping (ratio of stored to dissipated 
     energy or ratio of reactive to resistive energy). 
Fs   Free air resonance of driver in Hz. 
Qms Mechanical Q. 
Vas  Volume of air equivalent to driver from the rest position. 
Cms Mechanical compliance of a loud speaker piston. 
Mms Moving mass of total loud speaker piston assembly. 
Xmax The maximum linear excursion of a loud speaker. 
Sd   Surface area of the cone. 
Dia  The piston diameter of a loud speaker. 
Qes  Electrical Q of a system. 
Re   DC resistance. 
Le   VC inductance. 
Pe   Maximum input power. 
Qts  Total Q of the system. 
Sens Sensitivity. An efficiency measurement in dB’s. 
Vc   Volume of a closed or sealed enclosure 
Vb   Volume of a vented enclosure. 
Fc   The resonant frequency of a closed or sealed system 
Fb   The resonant frequency of a vented system 
F3   The half-power (-3dB) frequency of a loud speaker enclosure 
Qtc  The Q of a loud speaker at Fc in a closed box, considering both 
     it’s electrical and mechanical resistance. 
QL  The Q of a vented box, resulting from all box losses. 
DV  Diameter of vent. 
LV   Length of vent. 
H    Height. 
W   Width. 
D   Depth
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SM12D4
DVC 4-Ohms
PARALLEL
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2-Ohms
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SERIES
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PARALLEL COILS / PARALLEL SUBS
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SERIES COILS / PARALLEL SUBS
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1-Ohm
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8-Ohms
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4-Ohms
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SUBWOOFER DIMENSIONS
5.83” / 148mm
Mounting Depth
utotek
a
11.25” / 286mm Cut Out Diameter
12.24” / 311mm Outside Diameter
11.18” / 284mm 
When designing an enclosure for this subwoofer, please 
ensure to leave atleast 2” of clearance from the back of 
the motor to the back of the enclousre.
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Maxxsonics Limited Warranty
As the manufacturer of Maxxsonics, MB Quart, Autotek, Crunch and Hifonics car audio 
products, Maxxsonics USA Inc. Warrants to the original consumer purchaser the amplifier
to be free from defects in material and workmanship for one (1) Year from date of purchase.
All other parts and accessories of the system are warrantied to be free from defects in 
material and workmanship for one (1) year from date of purchase. Maxxsonics will 
repair or replace at it’s option and free of charge during the warranty period, any system 
component that proves defective in materials and workmanship under normal installation, 
use and service provided that the product is returned to the authorized Maxxsonics dealer 
from where it was purchased. A photo copy of the original receipt must accompany the 
product being returned.
Valid purchase receipts will contain the name and address of the authorized reseller.
Any damage to the product as a result of misuse, abuse, accident, incorrect wiring, 
improper installation, alteration of date code or bar code labels, revolution, natural 
disaster, or any sneaky stuff because someone messed up, repair or alteration out side 
of our factory or authorized service centers and any thing else you have done that you 
should not have done is not covered.
This warranty is limited to defective parts and specifically excludes any incidental 
or consequential damages connected therewith. This warranty is not to be construed 
as an insurance policy.
Warranty on installation labor, removal, re-installation and freight charges are not the 
responsibility of Maxxsonics USA Inc.
Warranty products damaged as a result of insufficient or improper packing materials 
are not covered by this limited warranty and such damaged product will be returned 
“as is” at the expense of the owner.
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