JBL · 3 Series MkIII · Studio monitor

308P MkIII

Product description
The largest two-way of the MkIII family: an 8-inch woofer down to 49 Hz and 113 dB peak, in a 444 mm cabinet that is a different proposition from the 305P on a desk. It shares the 306P's 110 W of Class-D rather than adding power, so the gain is cone area and headroom, not watts. Front-firing Slipstream port, 81 one-touch room-EQ presets. Announced November 2026, shipping in North America from January 2027.

Performance — where it sits in the catalog

BassTrebleCone area
Bass reachTreble reachCone area
308P MkIII49 Hz27 kHz329 cm²
Median39 Hz24 kHz332 cm²
How to read this chart

Each axis spans the range the 114 studio monitors in the catalog actually cover, so equal distance means equal difference — and for cone area and the two frequencies, which are read as ratios, equal distance means equal ratio. The dashed inner ring is where the scale starts, not zero. Ranked within a class because a bookshelf measured against floorstanders is feeble on every axis for the single reason that it is a bookshelf. Cone area is summed from the drive units — no maker publishes it. Bass and treble reach are quoted to different tolerances and only 56% of the catalog says which, so read those two axes as approximate. The grey outline is the median of this speaker's own class, the 96 active studio monitors — same type, same side of the active/passive line, which matters because the two halves are not the same product: the median active bookshelf carries 155 cm² of cone against the passive median's 219. Median rather than mean, because a handful of very large cabinets would drag a mean above most of the class it claims to describe. Not shown: Sensitivity, Easy load — the maker publishes no figure. Active speakers quote no sensitivity and no impedance, because with the amplifier inside both describe the electronics rather than the cabinet.

Units
TypeStudio monitor
HiFi ladder position#66 of 114 studio monitor
PowerActive
Height444 mm
Width249 mm
Depth296 mm
Footprint737 cm²
Space taken32.7 L
Weight8.8 kg
EnclosureBass reflex, front port
Drivers1× 25 mm tweeter (soft dome), 1× 203 mm woofer
Crossover frequency1960 Hz
Frequency response49–27000 Hz (±3 dB)
Amplification (per driver)tweeter 55 W (class D) · woofer 55 W (class D)
Total amp power110 W
Max SPL @ 1 m113 dB
Hi-res audio—
Wired inputsXLR balanced
Streaming / wireless—
Outputs—
Room correctionManufacturer presets
Primary + secondary pairNo
Wireless inter-speaker linkNo
Latency—
Idle power—
Max consumption—
Where to buyCheck availability ↗
Manufacturerjblpro.com ↗
Product pageOpen product page ↗

Suggested TrueScale comparisons

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