Quad 8 Inch Subwoofer Boxes

How to Choose a Quad 8 Inch Box

Start from the driver and buy a matched set

Most of these cabinets are cut to one named driver. Match the model and the coil on the listing, and run four of the same driver at the same impedance. The chambers are identical and the positions are paralleled inside the cabinet, so a different driver in one of them gets neither the volume it wants nor the same share of the power.

Work out the final impedance before you buy the amplifier

Because the cabinet parallels the driver positions, what is left to decide is how each driver's own coils are wired, and that gives two loads rather than the usual three. Four dual 4 ohm drivers land on 2 ohms with each driver's coils in series, or 0.5 ohms with them in parallel. Dual 2 ohm drivers land on 1 ohms or 0.25 ohms the same way. That puts a quad on the two loads most mono amplifiers are actually rated into, 2 ohms and 1 ohms, which is one of the quieter advantages of an even driver count. Calculate impedance for multiple subwoofers does the arithmetic for any set, and what 1 ohm stable means explains why the lowest reachable figure is not always the one to wire for.

Read the per-chamber volume, not the total

The total net volume tells you how big the cabinet is. The per-chamber figure tells you what each driver is working into, and that is the number that decides how the box sounds. Both are on every listing.

Sealed is the whole page

Every triple and quad cabinet we cut is sealed. At four drivers the port volume a vented box needs stops fitting in the space that made the high driver count attractive in the first place. If ported is what you want, it is a two driver or single driver build: the ported page has every vented cabinet.

Or step down a count

The dual 8 inch page and the single 8 inch page cover the same drivers in narrower cabinets.