HSD Sound Systems · Subwoofer

HSD Switchback

Name: HSD Sound Systems Switchback
Brand: HSD Sound Systems
SKU: 18FLH33
Price: 5200.00 USD
Availability: InStock

Model 18FLH33

Big low-end in a truck-pack-friendly footprint.

The Switchback delivers exceptional low-frequency performance in a versatile, space-efficient form factor. Balancing the critical elements of Hoffman's Iron Law, loudness, low-frequency extension, and compact size, it's the right compromise when you need powerful bass down to 32 Hz without sacrificing portability. Modular and scalable for touring, installs, and pop-up stages. Hand-built by Hennessey Sound Design in Massachusetts, and backed by a 5-year limited warranty.

$5,200 retail

Built to order. Quote includes freight, system design, and current lead time.

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HSD Sound Systems Switchback subwoofer by Hennessey Sound Design

Amplification

Passive cabinet, amplification required

The Switchback presents 8 ohms nominal and handles 1,000 W continuous. Two in parallel (4 ohms, 2,000 W) run on one 2,500 W channel of a KP Series 4-10KP, one amp drives eight Switchbacks.

1 amp channelper cabinet, 8Ω nominal

Driver

1×18″front-loaded horn

Response

32Hzto 150 Hz (-3 dB); 29 Hz at -10 dB

Power

1,000Wcontinuous (2,000 W program)

Weight

175 lbs38″ W × 24″ H × 36″ D

Full specifications

HSD Switchback (18FLH33) specs

Factory specifications from Hennessey Sound Design. Download the cut sheet for drawings and driver details.

Frequency Response	32 Hz - 150 Hz (-3 dB); 29 Hz - 150 Hz (-10 dB)
Sensitivity	105 dB (1W/1m)
Drivers	1 x 18" (front-loaded horn)
Power Handling	1,000 W continuous (2,000 W program)
Impedance	8 ohms nominal
Dimensions	38" W x 24" H x 36" D
Weight	175 lbs
Connectors	2 x NL4

HSD Switchback cut sheet (PDF)

Why buy from Fullblast

An HSD system is a build, not a box. We manage the whole thing.

Authorized HSD dealer

Fullblast Sound is one of only three authorized HSD Sound Systems dealers in the United States. Factory pricing, factory support, and a direct line to the Massachusetts shop on every order.

Real dealer support

We spec the system against your room and application, handle freight and logistics, and stay on call after delivery. Talk to us before you order and we will get the design right the first time.

Nationwide freight

Every HSD cabinet ships crated freight from the factory. We quote and coordinate delivery to your dock or venue anywhere in the country as part of the system price.

Financing available

Spread an HSD system across payments instead of a single check. See financing options or ask for terms with your quote.

Get a real quote

Send a system spec, not a price shopping number

Tell us the room, the audience size, and what you run today. We come back with the right HSD build, amplification, freight, and current factory lead time. One short form.

Request Quote Or call 210.489.0492

Same business day response.

Buyer research

Questions buyers ask about the Switchback

Common pre-purchase questions on the HSD Switchback.

What is the Switchback's design brief?

Hoffman's Iron Law says a speaker can be loud, deep, or small, pick two. The Switchback is HSD's deliberate compromise across all three: real 32 Hz (-3 dB) extension from a front-loaded horn that still fits a truck pack at 38 × 24 × 36 inches and 175 lbs. It is the sub you buy when portability is non-negotiable but 'portable sub bass' has always disappointed you.

What amplifier drives the Switchback?

1,000 W continuous (2,000 W program) at 8 ohms nominal. Two Switchbacks in parallel present 4 ohms and 2,000 W, comfortably inside one 2,500 W channel of the HSD KP Series 4-10KP or KD Series 4-10KD. One four-channel amp runs eight Switchbacks with FIR presets and per-channel limiting.

How does it scale?

It is modular by design: start with two, add pairs as the gigs grow, and cluster them for coupling gain. HSD also builds the Switchback XL, a 21″ big brother (model 21FLH30, $5,700) that keeps the same form factor with more output and reach; find it in the additional products table on our HSD hub page.

What tops pair with the Switchback?

The Uppercut is the natural match, a medium-format tri-amped top over a pair of Switchbacks is a complete high-output rig that two people can load. Add a V-Horn between them when the program demands dedicated mid-bass punch.

System design