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12" midbass speaker with 8-ohm voice coil
Item # 236RTX128 | MFR # RTX128
Our take on the MTX RTX128 by Crutchfield's John Pollard
They'll hear you coming
Are you looking to play your music loud? If so, you'll want to check out MTX's Road Thunder Extreme speakers, which use PA system technology to bring concert sound levels to your car. MTX built the RTX128 12" midbass speaker to fill in the frequencies in between where your tweeters and subwoofers play. And, believe us — this incredibly efficient speaker will give you plenty of volume when you feed it some serious power.
Built for high power
The RTX128 handles up to 300 watts RMS thanks to its hefty magnet, treated paper cone, and cloth surround. You can also easily run two of these 8-ohm speakers with a single amplifier channel, great news if you're installing two in each door. You can install this speaker in an enclosure if you want, but it works great in a free-air applications.
Note: This package contains one speaker. You'll need an external amplifier to drive this speaker properly an in-dash stereo won't have enough power.
What's in the Box:
- One 12" Midbass driver
- Specification sheet
- 12" midbass speaker with 8-ohm voice coil
- treated paper cone
- treated cloth surround
- power range: 50-300 watts RMS (900 watts peak power)
- frequency response: 66-5200 Hz
- sensitivity: 96 dB
- mounting depth: 4-15/16"
- warranty: 2 years
- Our 60-day money-back guarantee
- Fs (resonant frequency): 60.9 Hz
- Qms (mechanical Q at Fs): 10.375
- Cms (suspension compliance): 0.133 mm/N
- Mms (diaphragm/coil mass, including acoustic load): 51.434 g
- Rms (suspension's mechanical resistance): 1.898 kg/s
- Vas (equivalent compliance volume): 52.90 liters
- Xmax (maximum linear peak): 0.8 mm
- D (cone diameter): 10.24"
- Sd (cone area): 520.93 cm² (0.052093 m²)
- Vd (peak displacement volume): 0.042 liters
- Qes (Electrical Q at Fs): 0.771
- Re (voice coil DC resistance): 5.50 Ω
- Le (Voice coil inductance): 0.642 mH
- Bl (force factor): 11.86 Tm
- Qts (total Q at Fs): 0.718
- η0 (reference efficiency): 1.492%
- Peak Power: 900 watts
- SPL: 96.0 dB
- Frequency Response: 66 Hz to 5.2 kHz
- Recommended Crossover: 70 Hz high pass
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