Short answer: the GR-Research NX-Studio for better sound quality, the Klipsch RP-600M II for the lower price. The GR-Research NX-Studio ranks #4 of 130 bookshelf speakers at $3630. The Klipsch RP-600M II ranks #74 at $449.99, $3180.01 cheaper.
What the Klipsch RP-600M II offers: Redesigned waveguide extends flush to the baffle edge, reducing diffraction compared to the original RP-600M. Roughly 10-20° wider horizontal radiation than the original, giving more soundstage envelopment while retaining precise imaging. A major step up in overall tonal neutrality compared to the original RP-600M, largely eliminating that model’s midrange resonance issues. Unusually, sounds better with the grille on - the grille smooths out the elevated treble rather than degrading the sound, a rare trait among speakers the reviewer has tested. More refined back-panel hardware, including anodized binding posts and jumper cables for optional bi-amping. Responds well to EQ correction (verified using measurement software and a miniDSP), letting the on-axis response be made genuinely linear. Watch for: On-axis, the treble runs notably hot - even hotter than the original RP-600M in some respects - and needs about 20° of toe-out or the grille installed to sound balanced. Horizontal dispersion is very slightly less linear across angles than the original RP-600M, a minor trade-off for the wider overall radiation pattern. Klipsch’s marketed sensitivity (about 94.5dB) is, like the original, a half-space rating roughly 9dB above the anechoic reality (closer to 85-86dB). In-room bass rolls off around 60Hz in practice, and a 120Hz boost paired with a midrange scoop gives kick drums their “tambour” without real low-end weight - a subwoofer is still recommended. Vertical listening tolerance is limited to about ±10° from the tweeter axis. Toeing the speaker out for better on-axis tonality (rather than using the grille) introduces slightly more diffuse imaging from added sidewall reflections.
What the GR-Research NX-Studio offers: Ultra clean burst decay/waterfall plot. Amazingly open sounding due to the semi open baffle Neo3 ribbon tweeter, will image better than any other bookshelf speaker. Neo3 ribbon tweeter is one of the best ribbons around for detail. Bass will be very tight and fast due to the sealed enclosure, but may possibly need a sub. Watch for: Bass will be very tight but won’t be quite as deep as others due to the sealed woofer enclosure.
Buy the Klipsch RP-600M II when the price outweighs sound quality for you, and the GR-Research NX-Studio when sound quality outweighs the price instead.
Looking for alternatives? See the complete Passive Home rankings.
Specifications Side By Side
| Klipsch RP-600M II | GR-Research NX-Studio | |
|---|---|---|
| Price | $449.99 per pair | $3630 per pair |
| Ranked | #74 of 130 in Large Size Bookshelf Speakers | #4 of 130 in Large Size Bookshelf Speakers |
| Bass Extension (-10dB) | 41Hz (measured, Erin's Audio Corner) | - |
| Bass Extension (-3dB) | 70Hz (measured, Erin's Audio Corner) | - |
| Dimensions | 15.7"H x 8"W x 12.5"D (398.8 x 203.2 x 317.5 mm) | 18"H x 8.5"W x 15.5"D (457.2 x 215.9 x 393.7 mm) |
| Impedance | 8 ohms nominal (3.5 ohms minimum above 80Hz, measured by Erin's Audio Corner) | 8 ohms |
| Sensitivity | 86dB (measured, Erin's Audio Corner) | 87dB |
| Drivers | 6.5" Cerametallic cone woofer, 1" titanium LTS vented tweeter with Tractrix horn | GR-Research M165NQ 6.5" paper cone, non-resonant polymer frame, copper shorting rings and aluminum phase plug sealed enclosure woofer, GR-Research Neo3 Planar Magnetic Ribbon open baffle tweeter |
| Weight | 13 lbs (5.9 kg) each | 20.5 lbs (9.3 kg) each |
| Woofer Cabinet | ported | sealed |
| Spinorama Preference Score | 4.75 | - |
| Spinorama Preference Score with Perfect Sub | 6.88 | - |
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- GR-Research NX-Studio vs MoFi SourcePoint 10
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Prices on this page were last checked September 14, 2026 at 1:47 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
Klipsch RP-600M II: $449.99 per pair Amazon eBay
Pros: Redesigned waveguide extends flush to the baffle edge, reducing diffraction compared to the original RP-600M. Roughly 10-20° wider horizontal radiation than the original, giving more soundstage envelopment while retaining precise imaging. A major step up in overall tonal neutrality compared to the original RP-600M, largely eliminating that model’s midrange resonance issues. Unusually, sounds better with the grille on - the grille smooths out the elevated treble rather than degrading the sound, a rare trait among speakers the reviewer has tested. More refined back-panel hardware, including anodized binding posts and jumper cables for optional bi-amping. Responds well to EQ correction (verified using measurement software and a miniDSP), letting the on-axis response be made genuinely linear. Measured bass extension of 70Hz (-3dB), with a measured sensitivity of 86dB.
Cons: On-axis, the treble runs notably hot - even hotter than the original RP-600M in some respects - and needs about 20° of toe-out or the grille installed to sound balanced. Horizontal dispersion is very slightly less linear across angles than the original RP-600M, a minor trade-off for the wider overall radiation pattern. Klipsch’s marketed sensitivity (about 94.5dB) is, like the original, a half-space rating roughly 9dB above the anechoic reality (closer to 85-86dB). In-room bass rolls off around 60Hz in practice, and a 120Hz boost paired with a midrange scoop gives kick drums their “tambour” without real low-end weight - a subwoofer is still recommended. Vertical listening tolerance is limited to about ±10° from the tweeter axis. Toeing the speaker out for better on-axis tonality (rather than using the grille) introduces slightly more diffuse imaging from added sidewall reflections.
Full Klipsch RP-600M II review and specifications →
| Bass Extension (-10dB) | 41Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 70Hz (measured, Erin's Audio Corner) |
| Dimensions | 15.7"H x 8"W x 12.5"D (398.8 x 203.2 x 317.5 mm) |
| Drivers | 6.5" Cerametallic cone woofer, 1" titanium LTS vented tweeter with Tractrix horn |
| Impedance | 8 ohms nominal (3.5 ohms minimum above 80Hz, measured by Erin's Audio Corner) |
| Sensitivity | 86dB (measured, Erin's Audio Corner) |
| Spinorama Preference Score | 4.75 |
| Spinorama Preference Score with Perfect Sub | 6.88 |
| Weight | 13 lbs (5.9 kg) each |
| Woofer Cabinet | ported |
- Links
- Reviews, Comparisons and Sound Samples
- Erin’s Audio Corner: The Truth about Klipsch’s “NEW” Sound. RP-600M Update. More from Erin’s Audio Corner →
- Erin’s Audio Corner Website Klipsch RP-600M II
- GR-Research: We Bought The "NEW" RP-600M II Is KLIPSCH Listening?! More from GR-Research →
- Erin’s Audio Corner: 5 AWESOME SPEAKERS Under $1000 You Won’t Regret
- Erin’s Audio Corner Measurements (spinorama.org)
- Head-to-Head Comparisons
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- Klipsch RP-600M II vs Ascend CBM-170 SE2
- Klipsch RP-600M II vs Infinity Reference R162
- Klipsch RP-600M II vs GR-Research X-LS Encore
- Klipsch RP-600M II vs Infinity IL10
- See all 72 comparisons
GR-Research NX-Studio: $3630 per pair Gr-research eBay
Pros: Ultra clean burst decay/waterfall plot. Amazingly open sounding due to the semi open baffle Neo3 ribbon tweeter, will image better than any other bookshelf speaker. Neo3 ribbon tweeter is one of the best ribbons around for detail. Bass will be very tight and fast due to the sealed enclosure, but may possibly need a sub.
Cons: Bass will be very tight but won’t be quite as deep as others due to the sealed woofer enclosure.
Full GR-Research NX-Studio review and specifications →
| Dimensions | 18"H x 8.5"W x 15.5"D (457.2 x 215.9 x 393.7 mm) |
|---|---|
| Drivers | GR-Research M165NQ 6.5" paper cone, non-resonant polymer frame, copper shorting rings and aluminum phase plug sealed enclosure woofer, GR-Research Neo3 Planar Magnetic Ribbon open baffle tweeter |
| Impedance | 8 ohms |
| Sensitivity | 87dB |
| Weight | 20.5 lbs (9.3 kg) each |
| Woofer Cabinet | sealed |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- GR-Research NX-Studio vs KEF Reference 1 Meta
- GR-Research NX-Studio vs March Audio Sointuva AWG
- GR-Research NX-Studio vs AsciLab C6B
- GR-Research NX-Studio vs MoFi SourcePoint 10
- GR-Research NX-Studio vs ELAC Debut 3.0 DB63
- GR-Research NX-Studio vs HiVi Swans 3.1A Sehlin Sound Solutions mod
- GR-Research NX-Studio vs GR-Research X-LS Encore
- GR-Research NX-Studio vs ELAC Debut 2.0 B6.2
- See all 10 comparisons