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Thunder Axe Series 5"x7"/6"x8" component speaker system
Item # 236THND681 | MFR # THUNDER681
Our take on the MTX Thunder681 by Crutchfield's Alexander Hrabe
Speakers for the real world
MTX doesn't make speakers that only deliver the goods in a sound lab. This Thunder681 component system features a durable 5”x7"/6"x8” polypropylene woofer with a rubber surround that'll shrug off the weather and wear that come with living in your car full-time. You can swivel the 1-3/16" soft dome tweeter up to 15 degrees in your direction to really dial in the stereo imaging across your dash, and MTX includes hardware to flush- or surface-mounting.
The included crossover network features 2-level tweeter adjustment for fine-tuned sound staging. And, while no car speaker can produce bass like a large subwoofer, the Thunder681 woofers truly shine in the lower frequencies. With up to 90 watts RMS of power handling, you can add to their impressive depth and richness when you power them with an outboard amplifier.
Installation note: You'll need a pair of our universal backstraps to install the tweeters in the factory locations.
What's in the Box:
- 2 Woofers
- 2 Tweeters (7" wire attached)
- 2 Crossovers
- 2 Woofer bottom mount brackets
- 2 Surface mount tweeter housings (with tweeters installed)
- 2 Flush mount backing rings
- 2 Flush mount trim rings
- 2 Foam tweeter spacers
- Four 6" Speaker wires (each with quick slide terminals on one end and bare wire on the other)
- 2 Tweeter flush mounting clips
- Two M4x35mm machine screws
- Four 3/4" Flat-head screws
- Twelve 1" Self-tapping screws
- 12 Speed clips
- Cardboard template
- Mounting diagram
- Warranty information
- component speaker system includes 2 woofers, 2 tweeters, and 2 crossovers
- 5"x7"/6"x8" polypropylene cone with rubber surround
- 1-3/16" silk soft dome tweeter
- 2-way crossover with adjustable tweeter level
- power range: 2-90 watts RMS (180 watts peak power)
- frequency response: 46-20,000 Hz
- sensitivity: 90 dB
- impedance: 4 ohms
- woofer mounting depth: 2-1/2"
- warranty: 2 years
- Our 60-day money-back guarantee
Features and Specs
|Tweeter Design||30mm Dome|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
|Sensitivity (1W at 1 meter)||N/A|
|Sensitivity at 2.83 volts||90|
|Frequency Response||46 - 20k Hz|
|Minimum RMS Wattage||2|
|Maximum RMS Wattage||90|
|Peak Power Handling (Watts)||180|
|Top-mount Depth (Inches)||2 1/2|
|Bottom-mount Depth (Inches)||2 11/16|
|Cutout Diameter or Length (inches)||0|
Woofer Cones: The MTX Thunder Series speakers feature durable and rigid polypropylene woofer cones. Polypropylene is also resistant to the moisture and temperature extremes found in automotive applications.
Mounting Applications: MTX describes this woofer as a 6x8/5x7; it fits examples of both applications, but the hole spacing does not match Ford 6x8 applications and will require drilling new screw holes. Please enter your vehicle information to confirm fit.
Tweeter Mounting Options: The tweeters can be flush mounted or surface mounted using the included hardware. Once installed in either housing, the tweeter will pivot approximately 15° in any direction.
|Frame Diameter||Cutout Diameter||Mounting Height||Mounting Depth|
|Surface Mount||2.2"||N/A||1.035"||0.64" (Screw Depth)|
Crossovers: The crossover inputs and outputs are set screw terminals; they accept bare wire up to 10 gauge. There are two positive tweeter outputs, offering flat and -3dB output options. The screw terminals have 2mm Allen heads, and are recessed slightly more than half an inch, so a standard Allen head bit for a screw driver will not fit (an Allen wrench is not included). The crossover point is 4 kHz, the high pass slope is 18 dB/octave and the low pass slope is 6 dB/octave.
- Width: 4-15/16"
- Height: 1-3/8"
- Depth: 3-1/8"
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