Short answer: the KEF R3. It ranks #15 of 222 bookshelf speakers by sound quality, rated 4.5/5, at $1,544.56; the Arendal Sound 1723 Monitor THX ranks #55, rated 4.2/5, and costs $2,400, so there is not much of a tradeoff to weigh.
The KEF R3 is the more accurate 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. Its measured preference score, a predictor of how neutral it sounds, is 6.20 against 5.16 for the Arendal Sound 1723 Monitor THX. 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 Arendal Sound 1723 Monitor THX does well: A THX certified monitor with dual 8 inch woofers, a waveguide tweeter, and sturdy build for high output home theater rooms. Watch for: The measured on-axis average absolute deviation is 0.979dB and the sound-power directivity-index standard deviation is 3.63, so its response and dispersion are less even than the best alternatives.
Buy the KEF R3. It is rated higher for sound quality than the Arendal Sound 1723 Monitor THX and costs less, so only choose the other one for a particular feature it does better.
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Measured Differences
- Efficiency: the Arendal Sound 1723 Monitor THX is rated at 89 dB sensitivity against 86 dB for the KEF R3, so it plays as loud with roughly half the amplifier power.
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Specifications Side By Side
| KEF R3 | Arendal Sound 1723 Monitor THX | |
|---|---|---|
| Price | $1,544.56 per pair | $2,400 per pair |
| Ranked | #15 of 222 in Large Size Bookshelf Speakers | #55 of 222 in Large Size Bookshelf Speakers |
| Bass Extension (-3dB) | Approximately 58Hz (manufacturer specified; consistent with Erin’s measured roll-off) | 63Hz (measured, spinorama.org) |
| Bass Extension (-10dB) | 35.2Hz (measured, Audio Science Review) | approximately 37Hz (measured, spinorama.org) |
| Sensitivity | Approximately 86-87dB/2.83V/1m (measured, Erin’s Audio Corner) | 89dB (manufacturer specified, 2.83V/1m) |
| Impedance | 8 ohms nominal; suitable for Erin’s 4/8-ohm-rated amplifier | 4 ohms nominal |
| Drivers | 1” tweeter coaxial with 5” midrange; 6.5” woofer | Two 8-inch woofers; 28mm waveguided tweeter |
| Dimensions | 16.6”H x 7.9”W x 13.2”D | 15.7”H x 10.8”W x 25”D (400 x 275 x 635 mm) |
| Woofer Cabinet | ported, rear Flexible Port | - |
| Weight | 29.9 lbs (13.55 kg) each | 58.9 lbs (26.7 kg) each |
| Spinorama Preference Score | 6.2 (spinorama.org) | 5.16 |
| Spinorama Preference Score with Perfect Sub | 7.97 (spinorama.org) | 7.30 |
| DIY Kit | No | No |
| Certification | - | THX Ultra |
Where the Ratings Come From
- KEF R3: Spinorama.org measurements and reviews by Erin’s Audio Corner and Audio Science Review.
- Arendal Sound 1723 Monitor THX: Spinorama.org measurements and reviews by Erin’s Audio Corner.
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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