HYDRO-8 // 300 Watt RMS 8 Inch Shallow Mount Subwoofer
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CT Sounds is proud to introduce the hydro shallow mount subwoofer series after completing a rigorous R&D process spanning 2 years! Our goal was to engineer a 300-watt 8” shallow-mount subwoofer with a mounting depth below 3.5” that was suitable for both sealed & ported enclosures. To achieve this, we focused on the EBP (Efficiency Bandwidth Product). As a general rule, EBP < 50, is used only for sealed enclosures, EBP 50 - 100, is used for both, and EBP > 100, is used only for ported enclosures. EBP = FS/QES.
Quick Facts: | |
RMS Power: | 300 Watts |
MAX Power: | 600 Watts |
Voice Coil Configuration: | Dual 2 Ohm |
Use Cases: | Sealed & Ported Enclosures |
Our 1st prototype utilized a 50.8 mm voice coil & 30 oz magnet resulting in a high QES rating of 1.05 and low EBP of 44.1. The 2nd prototype utilized a 44.7 mm voice coil & 30 oz magnet resulting in a slightly lower QES rating of 0.843 and a slightly higher EBP of 54.8. After the 1st and 2nd prototypes, we determined a larger motor assembly was needed to provide a more controlled electrical system (lower QES). This led us to invest in a custom-tooled basket (used in the final prototype) to keep the mounting depth below 3.5”.
The 3rd and final prototype uses a 44.7 mm voice coil & 40 oz magnet resulting in a reduced QES rating of 0.577 and a balanced EBP of 80.07. In testing, we ran into mechanical noise due to the larger motor assembly and voice coil in a confined space. Therefore, we invested in a custom-tooled cone to maximize the excursion capability by creating an equal distance between the cone, spider, and bottom plate. The result is an 8” shallow-mount subwoofer that is extremely responsive in both sealed & ported enclosures.
General Specifications: | |
Product Type: | Car Subwoofer |
Subwoofer Size: | 8" |
Voice Coil Configuration: | Dual 2 Ohm |
RMS Power: | 300 Watts |
MAX Power: | 600 Watts |
Voice Coil Type: | 1.75 Inch - 4 Layer High-Temperature Copper Voice Coil |
Magnet Type: | Y35 |
Bottom Plate Type: | Low Carbon Iron |
Surround Type: | Dual White Stitched Competition Mega Foam Surround |
Cone Type: | Composite Paper with 3% Carbon Fiber Reinforcement |
Tinsel Lead Type: | Single Braided Flat Copper Tinsel Leads |
Terminal Type: | 12 Gauge Push Terminals |
Basket Type: | Stamped Steel |
Spider Material: | Poly-Cotton Blend |
T/S Parameters: | |
Qes: | 0.577 |
Qms: | 6.549 |
Qts: | 0.531 |
Fs: | 46.20 Hz |
Vas: | 10.298 L |
Mms: | 82.895 g |
Cms: | 0.143 m/N |
Re: | 3.9 Ω |
Bl: | 12.751 Tm |
Le: | / |
Sd: | 227 cm² |
Xmax - Single Way (mm): | 8 mm |
Xmax - Single Way (cm): | 0.8 cm |
Vd (Sd*Xmax): | 181.6 cm² |
SPL: | 84.48 dB |
Subwoofer Measurements: | |
Cutout diameter | 7.51" |
Overall diameter | 8.77" |
Mounting depth | 3.26" |
Box Specifications: | |
Displacement | 0.02 ft3 |
Box Recommendations: | |
Sealed | 0.35 ft3 |
Ported | 0.875 ft3 |
Tuning Frequency | 36 Hz |
Port Area | 14 in2 |
*Enclosure recommendations do not account for subwoofer, bracing, and port displacement.
CT Sounds is proud to introduce the hydro shallow mount subwoofer series after completing a rigorous R&D process spanning 2 years! Our goal was to engineer a 300-watt 8” shallow-mount subwoofer with a mounting depth below 3.5” that was suitable for both sealed & ported enclosures. To achieve this, we focused on the EBP (Efficiency Bandwidth Product). As a general rule, EBP < 50, is used only for sealed enclosures, EBP 50 - 100, is used for both, and EBP > 100, is used only for ported enclosures. EBP = FS/QES.
Quick Facts: | |
RMS Power: | 300 Watts |
MAX Power: | 600 Watts |
Coil Configuration: | Dual 4 Ohm |
Use Cases: | Sealed & Ported Enclosures |
Our 1st prototype utilized a 50.8 mm voice coil & 30 oz magnet resulting in a high QES rating of 1.21 and low EBP of 39.23. The 2nd prototype utilized a 44.7 mm voice coil & 30 oz magnet resulting in a slightly lower QES rating of 0.976 and a slightly higher EBP of 48.64. After the 1st and 2nd prototypes, we determined a larger motor assembly was needed to provide a more controlled electrical system (lower QES). This led us to invest in a custom-tooled basket (used in the final prototype) to keep the mounting depth below 3.5”.
The 3rd and final prototype uses a 44.7 mm voice coil & 40 oz magnet resulting in a reduced QES rating of 0.668 and a balanced EBP of 71.06. In testing, we ran into mechanical noise due to the larger motor assembly and voice coil in a confined space. Therefore, we invested in a custom-tooled cone to maximize the excursion capability by creating an equal distance between the cone, spider, and bottom plate. The result is an 8” shallow-mount subwoofer that is extremely responsive in both sealed & ported enclosures.
General Specifications: | |
Product Type: | Car Subwoofer |
Subwoofer Size: | 8" |
Voice Coil Configuration: | Dual 4 Ohm |
RMS Power: | 300 Watts |
MAX Power: | 600 Watts |
Voice Coil Type: | 1.75 Inch - 4 Layer High-Temperature Copper Voice Coil |
Magnet Type: | Y35 |
Bottom Plate Type: | Low Carbon Iron |
Surround Type: | Dual White Stitched Competition Mega Foam Surround |
Cone Type: | Composite Paper with 3% Carbon Fiber Reinforcement |
Tinsel Lead Type: | Single Braided Flat Copper Tinsel Leads |
Terminal Type: | 12 Gauge Push Terminals |
Basket Type: | Stamped Steel |
Spider Material: | Poly-Cotton Blend |
T/S Parameters: | |
Qes: | 0.668 |
Qms: | 6.083 |
Qts: | 0.602 |
Fs: | 47.47 Hz |
Vas: | 10.427 L |
Mms: | 77.535 g |
Cms: | 0.145 m/N |
Re: | 6.4 Ω |
Bl: | 14.880 Tm |
Le: | / |
Sd: | 227 cm² |
Xmax - Single Way (mm): | 8 mm |
Xmax - Single Way (cm): | 0.8 cm |
Vd (Sd*Xmax): | 181.6 cm² |
SPL: | 84.48 dB |
Subwoofer Measurements: | |
Cutout diameter | 7.51" |
Overall diameter | 8.77" |
Mounting depth | 3.26" |
Box Specifications: | |
Displacement | 0.02 ft3 |
Box Recommendations: | |
Sealed | 0.35 ft3 |
Ported | 0.875 ft3 |
Tuning Frequency | 36 Hz |
Port Area | 14 in2 |
*Enclosure recommendations do not account for subwoofer, bracing, and port displacement.
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