Music for York House

Relative price

above typical

Among the 24 subwoofers in the catalogue, this one is above typical.

A band places a component against its peers and carries no price. It is deliberately the only price indicator on this page: a second one, measured against a different set, would narrow the two together far enough to give the figure away.

What it is

PASSIVE subwoofer — fundamentally different topology from all 23 other catalog subs (which are powered/active). The Sub 3 sits in the signal chain BETWEEN the main amplifier and the main speakers, drawing its energy from the same amp via internal passive crossover. Plug-and-play; no controls, no adjustments — relies on placement for integration.

Designed by Derek Hughes (son of Spencer Hughes of Spendor; "keeper of the BBC flame") specifically for the Chartwell LS3/5 and LS3/5A. Hi-Fi+ (Aug 2018): "applicable to other designs of similar sensitivity and impedance" — therefore eligible for shortlist BBC-tradition speakers (Harbeth P3ESR-XD2, Falcon Gold Badge, Spendor Classic 4/5, Falcon Q7) but NOT for PMC Prodigy 1 (transmission line, different load) or Graham LS5/9 (already extended).

Crossover relieves main speakers of <100Hz energy, allowing them to play cleaner at higher SPL while the Sub 3 handles the bass extension. The main amp must have power headroom to drive BOTH the LS3/5 + Sub 3 — recommended amp power 30-80W unclipped programme. Air-cored inductors (zero saturation distortion) + polypropylene capacitors.

Hi-Fi+ review (Aug 2018, Alan Sircom): "extends that icon further into the bass without tampering with what makes the LS3/5a so special in the first place... existing owners of the classic BBC speaker would happily go for a bass add-on that retains the loudspeaker's agility than impose a new character."

Hi-Fi+ caveat: cannot match the speed/depth combination needed for orchestrally complex or fast-paced material — that requires either a larger main speaker or an active subwoofer. The Sub 3's purpose is BBC-monitor extension, not high-SPL bass authority.

COHERENCE RULE for system construction: Sub 3 is eligible only with shortlisted small BBC-tradition speakers (Graham-LS3-5, Harbeth-P3ESR-XD2, Falcon-GoldBadge, Spendor-Classic-4-5, Falcon-Q7). NOT with PMC-Prodigy1 (wrong topology/sensitivity) or Graham-LS5-9 (already extended).

SPL ACCOUNTING: Unlike active subs, the Sub 3 does not add separate amp power. Instead it (a) relieves main speakers of <100Hz energy (small SPL gain at the upper crossover) and (b) extends extension to 35Hz where main speakers had nothing. The bass-relief credit is ~+2dB in the operating band, not the +3dB that active subs deliver via separate amplification.

What the reviewers said

Graham Chartwell Sub 3 passive bass extender Graham Audio Chartwell Sub 3 (passive pair)· Bass extension

extension... into the double-digit zone Hi-Fi+ (Sircom) 2018· Bass extension

isn't big on punch Hi-Fi+ (Sircom) 2018· Physical impact

more majestic than fast Hi-Fi+ (Sircom) 2018· Bass control

How it scores

Bass

• Bass control 70 from listening evidence
• Physical impact 64 from listening evidence
• Bass extension 71 from listening evidence

Specifications