JBL 4305P vs JBL 308P MKII

Last updated: August 18, 2026

Short answer: the JBL 4305P for better sound quality, the JBL 308P MKII for the lower price. The JBL 4305P ranks #14 of 40 powered bookshelf speakers at $2200. The JBL 308P MKII ranks #24 at $498, $1702 cheaper.

What the JBL 4305P offers: Erin measured a 45Hz F3 and heard solid 40–50Hz in-room extension—excellent for a compact 5.25-inch active monitor. Watch for: The limiter becomes conspicuous around 96dB: Erin measured about 8dB lost near 50Hz at the highest drive and achieved roughly 93dB unweighted at 2m in-room.

On the JBL 308P MKII side: CEA2034 spinorama shows an essentially flat on-axis response from 45Hz to above 15kHz, with almost no directivity error. Set against that: A resonance shows up around 18kHz and a slight dip around 1.4kHz.

Buy the JBL 4305P if sound quality matters more than the price. Buy the JBL 308P MKII if the price matters more than sound quality.

JBL 4305P vs JBL 308P MKII

Specifications Side By Side

JBL 4305P JBL 308P MKII
Price$2,200/pair$498
Ranked#14 of 40 in Large Size Powered Bookshelf Speakers#24 of 40 in Large Size Powered Bookshelf Speakers
Bass Extension (-3dB)45Hz (measured, Erin’s Audio Corner)82Hz (measured, Audio Science Review)
SensitivityNot applicable (active DSP loudspeaker)-
Maximum Output~93dB at 2m in-room before limiting (measured, Erin’s Audio Corner)-
Amplification300W system: 125W LF + 25W HF per speaker-
Drivers5.25-inch pulp woofer; 1-inch annular compression driver8" woofer, 1" neodymium tweeter
Dimensions13.2H x 8.3W x 8.8D inches16.5"H x 10"W x 12.1"D (419.1 x 254 x 307.3 mm)
Bass Extension (-10dB)-60Hz (measured, Audio Science Review)
Frequency Response-45Hz - 20kHz (+/-3dB) (Manufacturer specified)
Weight-not published by manufacturer
App-No
EQ-No
DSP-No
Output Power-112W total

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The Two Speakers In Full

JBL 4305P: $2,200/pair Amazon JBL

JBL 4305P ranking card

Pros: Erin measured a 45Hz F3 and heard solid 40–50Hz in-room extension—excellent for a compact 5.25-inch active monitor. Tonality is neutral and non-fatiguing, vocal coloration is absent, imaging is precise, and the HDI horn maintains near-constant horizontal directivity above 2kHz. Each speaker is bi-amplified (125W LF + 25W HF), while USB, optical, balanced analog, AirPlay 2, Chromecast, Bluetooth and 24/192 wired interconnect make this an unusually complete system. Grilles caused no meaningful response penalty.

Cons: The limiter becomes conspicuous around 96dB: Erin measured about 8dB lost near 50Hz at the highest drive and achieved roughly 93dB unweighted at 2m in-room, so this is a near/midfield system rather than a high-output theater speaker. A baffle discontinuity produces a 1–2kHz directivity mismatch that cannot be corrected uniformly in the vertical plane; stay within about +/-5° of tweeter height. Soundstage depth and layering trailed the KEF Reference 1 Meta, and wireless speaker linking caps resolution at 24/96.

Amplification300W system: 125W LF + 25W HF per speaker
Bass Extension (-3dB)45Hz (measured, Erin's Audio Corner)
Dimensions13.2H x 8.3W x 8.8D inches
Drivers5.25-inch pulp woofer; 1-inch annular compression driver
Maximum Output~93dB at 2m in-room before limiting (measured, Erin's Audio Corner)
SensitivityNot applicable (active DSP loudspeaker)

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JBL 308P MKII: $498 Bhphotovideo

JBL 308P MKII ranking card

Pros: CEA2034 spinorama shows an essentially flat on-axis response from 45Hz to above 15kHz, with almost no directivity error. Dual 56W Class D amps drive an 8” woofer and 1” tweeter with a smooth, imperceptible crossover transition. Excellent value at $498 per pair.

Cons: A resonance shows up around 18kHz and a slight dip around 1.4kHz. An electronic limiter creates measurable anomalies around 96dB, and maximum clean output tops out around 105dB SPL before heavy limiting kicks in. Some audible tweeter hiss at close range.

AppNo
Bass Extension (-10dB)60Hz (measured, Audio Science Review)
Bass Extension (-3dB)82Hz (measured, Audio Science Review)
DSPNo
Dimensions16.5"H x 10"W x 12.1"D (419.1 x 254 x 307.3 mm)
Drivers8" woofer, 1" neodymium tweeter
EQNo
Frequency Response45Hz - 20kHz (+/-3dB) (Manufacturer specified)
Output Power112W total
Weightnot published by manufacturer

As an eBay Partner, we may be compensated if you make a purchase.