Short answer: the Genelec 8040B for better sound quality, the JBL 306P MKII for the lower price. The Genelec 8040B ranks #9 of 66 powered bookshelf speakers at $2350. The JBL 306P MKII ranks #39 at $398, $1952 cheaper.
What the Genelec 8040B offers: Based on their smaller speaker’s performance against others, I’m ranking this accordingly. Watch for: Very expensive
What the JBL 306P MKII offers: CEA2034 spinorama shows a nice, smooth on-axis response with very good directivity control for a compact 6.5” monitor. Dual 56W Class D amps keep the design affordable at $398 per pair while following JBL’s well-regarded 300-series voicing. Watch for: A narrow but noticeable dip around 1.6kHz shows up in the on-axis and listening-window curves. Distortion runs classically high for this series, reaching around 5% near 200Hz at 96dB SPL. Amplifier hiss is audible from roughly 2 feet away, and the monitor runs out of headroom at higher volumes.
Buy the Genelec 8040B if sound quality matters more than the price. Buy the JBL 306P MKII if the price matters more than sound quality.
Specifications Side By Side
| Genelec 8040B | JBL 306P MKII | |
|---|---|---|
| Price | $2350 | $398 |
| Ranked | #9 of 66 in Large Size Powered Bookshelf Speakers | #39 of 66 in Large Size Powered Bookshelf Speakers |
| Dimensions | 14.4"H x 9.3"W x 8.8"D (365.8 x 236.2 x 223.5 mm) | 16.1"H x 11.2"W x 12.9"D (408 x 285 x 328 mm) |
| Frequency Response | 41Hz - 25kHz (-6dB) (Manufacturer specified) | 39Hz - 24kHz (-10dB) (Manufacturer specified) |
| Inputs | XLR | - |
| Weight | 20.7 lbs / 9.4 kg each | 13.4 lbs / 6.1 kg each |
| Drivers | 6.5" (165mm) woofer | 6.5" woofer, 1" neodymium tweeter |
| App | No | No |
| Bluetooth | No | - |
| EQ | Yes (Room adjustment) | No |
| DSP | No | No |
| Output Power | 180w Per Speaker | 112W total |
| Bass Extension (-3dB) | - | 78Hz (measured, Audio Science Review) |
| Bass Extension (-10dB) | - | 60Hz (measured, Audio Science Review) |
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Prices on this page were last checked August 25, 2026 at 6:19 AM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Speakers In Full
Genelec 8040B: $2350 Bhphotovideo eBay
Pros: Based on their smaller speaker’s performance against others, I’m ranking this accordingly.
Cons: Very expensive
Full Genelec 8040B review and specifications →
| App | No |
|---|---|
| Bluetooth | No |
| DSP | No |
| Dimensions | 14.4"H x 9.3"W x 8.8"D (365.8 x 236.2 x 223.5 mm) |
| Drivers | 6.5" (165mm) woofer |
| EQ | Yes (Room adjustment) |
| Frequency Response | 41Hz - 25kHz (-6dB) (Manufacturer specified) |
| Inputs | XLR |
| Output Power | 180w Per Speaker |
| Weight | 20.7 lbs / 9.4 kg each |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
JBL 306P MKII: $398 Bhphotovideo eBay
Pros: CEA2034 spinorama shows a nice, smooth on-axis response with very good directivity control for a compact 6.5” monitor. Dual 56W Class D amps keep the design affordable at $398 per pair while following JBL’s well-regarded 300-series voicing.
Cons: A narrow but noticeable dip around 1.6kHz shows up in the on-axis and listening-window curves. Distortion runs classically high for this series, reaching around 5% near 200Hz at 96dB SPL. Amplifier hiss is audible from roughly 2 feet away, and the monitor runs out of headroom at higher volumes.
Full JBL 306P MKII review and specifications →
| App | No |
|---|---|
| Bass Extension (-10dB) | 60Hz (measured, Audio Science Review) |
| Bass Extension (-3dB) | 78Hz (measured, Audio Science Review) |
| DSP | No |
| Dimensions | 16.1"H x 11.2"W x 12.9"D (408 x 285 x 328 mm) |
| Drivers | 6.5" woofer, 1" neodymium tweeter |
| EQ | No |
| Frequency Response | 39Hz - 24kHz (-10dB) (Manufacturer specified) |
| Output Power | 112W total |
| Weight | 13.4 lbs / 6.1 kg each |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons