Short answer: the KEF R3. It ranks #15 of 222 bookshelf speakers by sound quality, rated 4.5/5, at $1,544.56. The Fosi Audio SP601 ranks #201, rated 2.7/5, at $399.99, $1,144.57 cheaper, which does not close the gap in sound quality.
The KEF R3 is the better-sounding pick. A three way bookshelf speaker with KEF’s coaxial driver for stable imaging across seats and very low distortion, easy to run with a modest amp. The tradeoff: The low-frequency alignment rolls gradually rather than delivering high-output sub-bass; KEF specifies 58Hz +/-3dB and Erin’s high-level data supports using an 80Hz subwoofer crossover.
What the Fosi Audio SP601 does well: A budget bookshelf speaker with a 6.5 inch woofer and respectable bass that improves noticeably with simple EQ. The catch: An unusually erratic, up-and-down frequency response (a scooped midrange followed by an upper-mid bump, a dip, another small bump, then a strong 3-4dB peak around 4-7kHz) makes the speaker’s overall character genuinely hard to characterize: the reviewer compared the experience to a similarly disliked model, the Triangle Borea BR03, which has a comparably inconsistent response.
Buy the KEF R3. It is rated higher for sound quality, and the $1,144.57 you would save on the Fosi Audio SP601 does not close the gap.
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Measured Differences
- Close enough not to matter: bass extension (35.2 Hz vs 40 Hz, 10 dB down).
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Specifications Side By Side
| KEF R3 | Fosi Audio SP601 | |
|---|---|---|
| Price | $1,544.56 per pair | $399.99 per pair |
| Ranked | #15 of 222 in Large Size Bookshelf Speakers | #201 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-3dB) | Approximately 58Hz (manufacturer specified; consistent with Erin’s measured roll-off) | 59Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-10dB) | 35.2Hz (measured, Audio Science Review) | 40Hz (measured, Erin’s Audio Corner) |
| Sensitivity | Approximately 86-87dB/2.83V/1m (measured, Erin’s Audio Corner) | 85.4dB (measured, Erin’s Audio Corner) |
| Impedance | 8 ohms nominal; suitable for Erin’s 4/8-ohm-rated amplifier | 4 ohms nominal, 4.1 ohms minimum (measured, Erin’s Audio Corner) |
| Drivers | 1” tweeter coaxial with 5” midrange; 6.5” woofer | 6.5” woofer, 1.5” Silk Dome Tweeters |
| Dimensions | 16.6”H x 7.9”W x 13.2”D | 14.5”H x 9.1”W x 14”D (368.3 x 231.1 x 355.6 mm) |
| Woofer Cabinet | ported, rear Flexible Port | ported, rear |
| Weight | 29.9 lbs (13.55 kg) each | 11.5 lbs (5.2 kg) |
| Spinorama Preference Score | 6.2 (spinorama.org) | - |
| Spinorama Preference Score with Perfect Sub | 7.97 (spinorama.org) | - |
| DIY Kit | No | No |
| App | - | No |
| EQ | - | No |
| DSP | - | No |
| Power Handling | - | 80w RMS Per Speaker |
Where the Ratings Come From
- KEF R3: Spinorama.org measurements and reviews by Erin’s Audio Corner and Audio Science Review.
- Fosi Audio SP601: reviews by Erin’s Audio Corner and Audio Science Review Fosi Audio SP60.
This comparison is generated from the ratings, specifications and measurements on each product’s own page, and it updates when that data changes. How we rank explains how each rating is decided.
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