Seventour 10-inch Shallow Mount Dual 4 Ohm Car Subwoofer: specs explained

The Seventour HR-DTSUB is a 10-inch component car subwoofer with a shallow mounting depth and dual 4-ohm voice coils. It is a bare driver, meant to go into an enclosure and be powered by a separate amplifier. This page explains the numbers in its specifications.

Shallow mount, and why depth matters

Subwoofers need space behind the cone to work properly. A shallow-mount design is built for tight spots, such as under a seat or in a slim box in the boot (trunk) or a truck cab. Seventour lists a recommended installation depth of 7.08 inches (about 18 cm). The boxed dimensions are about 14 x 14 x 9.3 inches (36 x 36 x 24 cm). Always check the manual or the maker for the enclosure volume the driver expects, since that affects bass quality.

RMS and peak power

The listing gives 1,200 watts peak and 600 watts RMS. RMS is the continuous power a driver is meant to handle, and it is the number to match to an amplifier. Peak is a short-burst figure and is generally much less useful. An amplifier delivering close to the RMS figure, at the right impedance, is a common target.

Dual 4-ohm voice coils

A dual-voice-coil subwoofer has two coils, each rated at 4 ohms. They can be wired in parallel for a 2-ohm load or in series for an 8-ohm load. The choice should match the amplifier, which has a minimum stable impedance and a power output that changes with the load. Wiring diagrams are in the manual. If the amp is not rated for the final load, it may overheat.

Frequency response, sensitivity and resonance

• 28 Hz to 300 Hz: the range the driver covers. Most subwoofers are crossed over below about 80 to 100 Hz in practice, so the top end is rarely used.
• Sensitivity of 82 dB: the sound level at a standard test power and distance. A lower number means more amplifier power is needed for the same volume.
• FS of 40 Hz: the free-air resonance frequency, where the driver naturally moves most. It influences enclosure design.

Who it suits

It suits drivers who want to add low bass in a place with limited depth, as a part of a custom or upgraded system. It is not a complete package: it does not include an amplifier, box or wiring.

What to check before you buy

• Space: measure the mounting depth and compare it with the 7.08-inch recommendation.
• Enclosure: choose a sealed or ported box with the volume the maker advises.
• Amplifier: match its output to the 600W RMS figure and to the impedance you wire.
• Wiring: you will need gauge-appropriate power wire, fusing and signal cables.
• Crossover and settings: adjust the amplifier or head unit as the manuals describe.
• Fit and noise: secure the box so it does not rattle, and check local rules on sound levels.

The short version

• A 10-inch shallow-mount component subwoofer, model HR-DTSUB.
• 1,200W peak and 600W RMS, with dual 4-ohm voice coils.
• 28 Hz to 300 Hz response, 82 dB sensitivity, 40 Hz FS.
• Recommended installation depth of 7.08 inches.
• An enclosure and an amplifier are needed.

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