Short answer: the Polk Reserve R100. It ranks #154 of 214 bookshelf speakers by sound quality, rated 3.4/5, at $559; the Triangle Borea BR04 ranks #184, rated 3.0/5, and costs $649, so there is not much of a tradeoff to weigh.
The Polk Reserve R100 is the better-sounding choice. Compact cabinet, unusually useful bass for its size and well-controlled woofer breakup. Watch for: Erin measured only about 85dB sensitivity and the impedance reaches 3.6 ohms, so it is neither efficient nor an entirely benign AVR load.
Why pick the Triangle Borea BR04: A larger Triangle Borea BR03 with a 6.3” cellulose woofer and a front port, rated from 44Hz at 90dB, so it is easy to drive and can sit near a wall. Watch for: No independent measurements yet, so its tonal balance and directivity can’t be compared with ranked speakers.
Buy the Polk Reserve R100. It is rated higher for sound quality than the Triangle Borea BR04 and costs less, so only choose the other one for a particular feature it does better.
About the ratings: the Triangle Borea BR04’s rating is estimated from measured siblings and predecessors rather than its own measurements, with a likely range of 2.7 to 3.3, so this verdict could change once it is measured.
Still deciding? The full Passive Home rankings cover every ranked option.
Specifications Side By Side
| Polk Reserve R100 | Triangle Borea BR04 | |
|---|---|---|
| Price | $559.00 per pair | $649.00 per pair |
| Ranked | #154 of 214 in Large Size Bookshelf Speakers | #184 of 214 in Large Size Bookshelf Speakers Estimated |
| Bass Extension (-3dB) | 68Hz (measured, Erin’s Audio Corner) | - |
| Bass Extension (-10dB) | 49Hz (measured, Erin’s Audio Corner) | - |
| Sensitivity | 85dB/2.83V/1m (measured, Erin’s Audio Corner) | 90dB (manufacturer specified) |
| Impedance | 3.6 ohms minimum (measured, Erin’s Audio Corner) | 8 ohms nominal (manufacturer specified) |
| Drivers | 1” Pinnacle ring-radiator tweeter; 5.25” Turbine Cone midwoofer | 1x 1” EFS silk dome tweeter, 1x 6.3” cellulose pulp woofer |
| Dimensions | 12.8”H x 6.5”W x 10.2”D | 16.7”H x 8.7”W x 12.4”D (425 x 220 x 314 mm) |
| Weight | 12.1 lbs (5.5 kg) each | 19 lbs (8.6 kg) each |
| Woofer Cabinet | ported, rear X-Port | - |
| Spinorama Preference Score | 5.46 | - |
| Spinorama Preference Score with Perfect Sub | 7.93 | - |
| DIY Kit | No | - |
| Frequency Response | - | 44Hz - 22kHz (manufacturer specified) |
| Amplifier Power | - | 25-130W recommended |
| Enclosure | - | Front ported |
Related Speaker Comparisons
How Polk Reserve R100 compares with other leading options:
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- KEF R3 Meta vs Polk Reserve R100
- KEF Q Concerto Meta vs Polk Reserve R100
- KEF R3 vs Polk Reserve R100
- MoFi SourcePoint 8 vs Polk Reserve R100
Prices on this page were last checked October 11, 2026 at 4:59 PM 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
Polk Reserve R100: $559.00 per pair Amazon Polk Audio eBay
Same family: the Polk R200 (larger bookshelf, ranked lower, rated 3.2/5), the Polk Reserve R500 (smallest floorstanding, rated 4.2/5), the Polk Reserve R600 (floorstanding, estimated 4.2/5), the Polk Audio Reserve R700 (largest floorstanding, rated 4.3/5), the Polk Audio Reserve R300 (smallest center, estimated 3.6/5), the Polk Audio Reserve R350 (center, rated 3.7/5) and the Polk Audio Reserve R400 (largest center, estimated 3.8/5).
Pros: Compact cabinet, unusually useful bass for its size and well-controlled woofer breakup. Erin measured F3/F10 points of 68Hz/49Hz, and the X-Port vent avoids much of the chuffing and pipe resonance common to budget rear ports. The 5.25-inch Turbine Cone woofer and 1-inch Pinnacle ring-radiator tweeter produce good detail at moderate levels, while listening roughly 20° off-axis reduces part of the elevated top octave. Measured bass extension of 68Hz (-3dB), with a measured sensitivity of 85dB.
Cons: Erin measured only about 85dB sensitivity and the impedance reaches 3.6 ohms, so it is neither efficient nor an entirely benign AVR load. The treble runs roughly 3dB above the midrange and becomes aggressive above about 85dB SPL. A directivity discontinuity through the woofer/tweeter crossover means EQ cannot fully repair the power response, and a 400Hz impedance feature plus 500Hz-1kHz response irregularity suggests a cabinet or system resonance. Substantial low-frequency compression at higher playback levels limits clean dynamics.
Full Polk Reserve R100 review and specifications →
| Released | 2021 (5 years ago) |
|---|---|
| Bass Extension (-10dB) | 49Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-3dB) | 68Hz (measured, Erin’s Audio Corner) |
| DIY Kit | No |
| Dimensions | 12.8”H x 6.5”W x 10.2”D |
| Drivers | 1” Pinnacle ring-radiator tweeter; 5.25” Turbine Cone midwoofer |
| Impedance | 3.6 ohms minimum (measured, Erin’s Audio Corner) |
| Sensitivity | 85dB/2.83V/1m (measured, Erin’s Audio Corner) |
| Spinorama Preference Score | 5.46 |
| Spinorama Preference Score with Perfect Sub | 7.93 |
| Weight | 12.1 lbs (5.5 kg) each |
| Woofer Cabinet | ported, rear X-Port |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Polk Reserve R100 vs Sonus Faber Lumina II
- Polk Reserve R100 vs Polk Monitor XT20
- Polk Reserve R100 vs KEF Q3 Meta
- Polk Reserve R100 vs Focal Aria 906
- Polk Reserve R100 vs Revel Performa M22
- Polk Reserve R100 vs HSU Research MFL-6
- Polk Reserve R100 vs SVS Prime Bookshelf
- Polk Reserve R100 vs ELAC Debut 2.0 B6.2
- See all 31 comparisons
Triangle Borea BR04: $649.00 per pair Estimated Amazon eBay
Same family: the Triangle Borea BR02 (smaller bookshelf, estimated 2.7/5), the Triangle Borea BR03 (smaller bookshelf, ranked lower, rated 2.8/5), the Triangle Borea BR07 (smallest floorstanding, estimated 3/5), the Triangle Borea BR08 (floorstanding, estimated 3.2/5), the Triangle Borea BR09 (floorstanding, estimated 3.3/5), the Triangle Borea BR10 (largest floorstanding, estimated 3.3/5), the Triangle Borea BRC01 (smaller center, estimated 3.4/5) and the Triangle Borea BRC2 (larger center, estimated 3.3/5).
Pros: A larger Triangle Borea BR03 with a 6.3” cellulose woofer and a front port, rated from 44Hz at 90dB, so it is easy to drive and can sit near a wall.
Cons: No independent measurements yet, so its tonal balance and directivity can’t be compared with ranked speakers. Its measured sibling the BR03 sits low in the rankings.
Full Triangle Borea BR04 review and specifications →
| Amplifier Power | 25-130W recommended |
|---|---|
| Dimensions | 16.7”H x 8.7”W x 12.4”D (425 x 220 x 314 mm) |
| Drivers | 1x 1” EFS silk dome tweeter, 1x 6.3” cellulose pulp woofer |
| Enclosure | Front ported |
| Frequency Response | 44Hz - 22kHz (manufacturer specified) |
| Impedance | 8 ohms nominal (manufacturer specified) |
| Sensitivity | 90dB (manufacturer specified) |
| Weight | 19 lbs (8.6 kg) each |
- Links
- Reviews, Comparisons and Sound Samples
- No independent measurement review is linked for this model; it is ranked from hands-on listening and comparison against similarly priced speakers.
- Head-to-Head Comparisons