Short answer: the Polk Monitor XT20. It ranks #91 of 131 bookshelf speakers by sound quality; the Wharfedale Diamond 9.1 ranks #109.
What the Polk Monitor XT20 offers: Two-way bookshelf design with a 1” tweeter and 6.5” woofer, part of Polk’s budget-friendly XT lineup (spanning roughly $200-700 across the series). Measures more linear and has fewer/smaller cabinet resonances than its smaller sibling, the XT15, making it - by the reviewer’s own assessment - probably the better of the two based on data alone. Reasonably good bass output for the price and size, with an F3 of 63Hz. Horizontal radiation of about ±50° gives a respectable, enjoyable soundstage width. Takes well to EQ correction - the early-reflections directivity trend is decently linear, meaning tonal adjustments can meaningfully improve the sound. Provides usable, respectable volume when paired with a subwoofer crossover, even though it isn’t intended to play extremely loud on its own. Watch for: Notably bright treble, elevated roughly 1-5dB above the midrange depending on frequency - a characteristic shared across the whole Polk XT lineup, requiring either EQ or toe-out to tame. Small resonances appear around 300Hz and 800Hz, with some of that energy leaking from the port area. Vertical listening window is narrow - best kept close to the tweeter axis, with only a couple of degrees of tolerance above or below before the sound changes. Still needs a subwoofer for real low-end extension despite the decent F3. Overall linearity isn’t state-of-the-art flat, and while the reviewer found it pleasant, some artificial brightness remains even after basic EQ correction in the crossover region.
What the Wharfedale Diamond 9.1 offers: The first design was a pretty good sounding speaker, the speaker was then outsourced to China and lost 1.5kg and was made with cheap parts and sounds much worse. Slightly rolled off in the treble by about 3dB Watch for: All current new ones sold today are the crap version.
Buy the Polk Monitor XT20 if sound quality matters more than the price. Buy the Wharfedale Diamond 9.1 if the price matters more than sound quality.
If sound quality matters at all to you, skip the Wharfedale Diamond 9.1. It ranks near the bottom of the 131 bookshelf speakers, so look higher up the list instead.
Specifications Side By Side
| Polk Monitor XT20 | Wharfedale Diamond 9.1 | |
|---|---|---|
| Price | $279.00 | Discontinued |
| Ranked | #91 of 131 in Large Size Bookshelf Speakers | #109 of 131 in Large Size Bookshelf Speakers |
| Bass Extension (-10dB) | 50Hz (measured, Erin’s Audio Corner) | - |
| Bass Extension (-3dB) | 75Hz (measured, Erin’s Audio Corner) | - |
| Dimensions | 13"H x 7.5"W x 11"D (330.2 x 190.5 x 279.4 mm) | 11.7"H x 7.6"W x 10.9"D (296.0 x 194.0 x 278.0 mm) |
| Impedance | 8 ohms nominal (measured, Erin’s Audio Corner) | 6 ohms |
| Sensitivity | 86dB (measured by Erin’s Audio Corner; 87dB manufacturer specified) | 87dB |
| Drivers | 6.5" bilaminate paper cone woofer, 1" Terylene dome tweeter | 6.5" Kevlar cone woofer, 1" soft dome tweeter |
| Weight | 11.9 lbs / 5.4 kg each | 12.1 lbs / 5.5 kg (good version), 9.9 lbs / 4.5 kg (bad version) each |
| Woofer Cabinet | ported | ported |
| Discontinued | - | Yes |
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- ELAC Debut 2.0 B6.2 vs Polk Monitor XT20
- Polk Monitor XT20 vs Klipsch RP-600M
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The Two Speakers In Full
Polk Monitor XT20: $279.00 Amazon Crutchfield eBay
Pros: Two-way bookshelf design with a 1” tweeter and 6.5” woofer, part of Polk’s budget-friendly XT lineup (spanning roughly $200-700 across the series). Measures more linear and has fewer/smaller cabinet resonances than its smaller sibling, the XT15, making it - by the reviewer’s own assessment - probably the better of the two based on data alone. Reasonably good bass output for the price and size, with an F3 of 63Hz. Horizontal radiation of about ±50° gives a respectable, enjoyable soundstage width. Takes well to EQ correction - the early-reflections directivity trend is decently linear, meaning tonal adjustments can meaningfully improve the sound. Provides usable, respectable volume when paired with a subwoofer crossover, even though it isn’t intended to play extremely loud on its own.
Cons: Notably bright treble, elevated roughly 1-5dB above the midrange depending on frequency - a characteristic shared across the whole Polk XT lineup, requiring either EQ or toe-out to tame. Small resonances appear around 300Hz and 800Hz, with some of that energy leaking from the port area. Vertical listening window is narrow - best kept close to the tweeter axis, with only a couple of degrees of tolerance above or below before the sound changes. Still needs a subwoofer for real low-end extension despite the decent F3. Overall linearity isn’t state-of-the-art flat, and while the reviewer found it pleasant, some artificial brightness remains even after basic EQ correction in the crossover region.
Full Polk Monitor XT20 review and specifications →
| Bass Extension (-10dB) | 50Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 75Hz (measured, Erin's Audio Corner) |
| Dimensions | 13"H x 7.5"W x 11"D (330.2 x 190.5 x 279.4 mm) |
| Drivers | 6.5" bilaminate paper cone woofer, 1" Terylene dome tweeter |
| Impedance | 8 ohms nominal (measured, Erin's Audio Corner) |
| Sensitivity | 86dB (measured by Erin's Audio Corner; 87dB manufacturer specified) |
| Weight | 11.9 lbs / 5.4 kg each |
| Woofer Cabinet | ported |
- Links
- Reviews, Comparisons and Sound Samples
- Erin’s Audio Corner: Polk’s new budget XT Speakers. Reviewed! More from Erin’s Audio Corner →
- Erin’s Audio Corner Website Polk Monitor XT20
- Erin’s Audio Corner: 10 Great (and Terrible) Speakers Under $300!
- Erin’s Audio Corner: Budget Stereo Systems You Will Love
- Erin’s Audio Corner Measurements (spinorama.org)
- Reddit Search for Polk Monitor XT20 Review
- Head-to-Head Comparisons
- Polk Monitor XT20 vs KEF Q3 Meta
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- Polk Monitor XT20 vs Revel Performa M22
- Polk Monitor XT20 vs Dynaudio Special Forty
- Polk Monitor XT20 vs Infinity IL10
- See all 37 comparisons
Wharfedale Diamond 9.1: Discontinued eBay
Pros: The first design was a pretty good sounding speaker, the speaker was then outsourced to China and lost 1.5kg and was made with cheap parts and sounds much worse. Slightly rolled off in the treble by about 3dB
Cons: All current new ones sold today are the crap version. Discontinued.
Full Wharfedale Diamond 9.1 review and specifications →
| Dimensions | 11.7"H x 7.6"W x 10.9"D (296.0 x 194.0 x 278.0 mm) |
|---|---|
| Discontinued | Yes |
| Drivers | 6.5" Kevlar cone woofer, 1" soft dome tweeter |
| Impedance | 6 ohms |
| Sensitivity | 87dB |
| Weight | 12.1 lbs / 5.5 kg (good version), 9.9 lbs / 4.5 kg (bad version) each |
| Woofer Cabinet | ported |
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Wharfedale Diamond 9.1 vs Klipsch RP-600M
- Wharfedale Diamond 9.1 vs Triangle Borea BR03
- Wharfedale Diamond 9.1 vs Sonus Faber Lumina II Amator
- Wharfedale Diamond 9.1 vs B&W 805S
- Wharfedale Diamond 9.1 vs KEF Q350
- Wharfedale Diamond 9.1 vs Aperion Audio Verus V8B
- Wharfedale Diamond 9.1 vs Sonus Faber Sonetto II G2
- Wharfedale Diamond 9.1 vs Triad In-Room Gold LCR
- See all 23 comparisons