Short answer: the KEF R5. It ranks #10 of 59 floorstanding speakers by sound quality at $2999; the JBL HDI-3600 ranks #23 and costs $3800, so there is not much of a tradeoff to weigh.
On the KEF R5 side: Slim three-way tower with the acoustic advantages of KEF’s coincident Uni-Q midrange/tweeter: horizontal and vertical off-axis responses track the direct sound smoothly, producing stable imaging and a well-behaved directivity index. The catch: The unusual gap between 77Hz F3 and 33Hz F10 indicates a gradual bass contour rather than flat deep-bass output; a subwoofer and roughly 80Hz high-pass are recommended for high-level playback.
What the JBL HDI-3600 offers: CEA2034 spinorama shows a fairly even on-axis response and flat overall frequency response, with high 90dB sensitivity and very low distortion through the midrange. Watch for: A wide shelving-down above 2kHz affects the in-room response, and vertical dispersion is a bigger issue than horizontal - the reviewer noted the dip is wider here than on the smaller HDI-1600, making it more audible.
Buy the KEF R5. It ranks higher for sound quality than the JBL HDI-3600 and costs less, so there is no real case for the other one.
Specifications Side By Side
| KEF R5 | JBL HDI-3600 | |
|---|---|---|
| Price | $2,999/pair Discontinued | $3800 |
| Ranked | #10 of 59 in Large Size Floorstanding Speakers | #23 of 59 in Large Size Floorstanding Speakers |
| Bass Extension (-3dB) | 77Hz (measured, Erin’s Audio Corner) | 78Hz - the on-axis curve also shows an unusual step/dip around 40-55Hz that may be a near-field-scan artifact for this tower (measured, Audio Science Review) |
| Bass Extension (-10dB) | 33Hz (measured, Erin’s Audio Corner) | 62Hz - the on-axis curve also shows an unusual step/dip around 40-55Hz that may be a near-field-scan artifact for this tower (measured, Audio Science Review) |
| Sensitivity | Approximately 86dB/2.83V/1m (measured, Erin’s Audio Corner) | 89.5dB (2.83V/1m, measured, Audio Science Review) |
| Impedance | Approximately 3.5 ohms minimum near 150Hz (measured, Erin’s Audio Corner) | 4 ohms nominal |
| Drivers | 1" aluminum tweeter coaxial with 5" midrange; dual 5.25" woofers | 2410H-2 1" compression driver, 3x 6.5" Advanced Aluminum Matrix woofers |
| Dimensions | 40.4"H x 6.9"W x 13.5"D | 40.5"H x 10.2"W x 13.5"D (1029 x 260 x 343 mm) |
| Discontinued | Yes | - |
| Weight | 59.5 lb each | 61.7 lbs / 28 kg each |
| Woofer Cabinet | ported, rear | ported, dual rear-firing |
| Frequency Response | - | 38Hz - 30kHz (+/-3dB) (Manufacturer specified) |
Related Speaker Comparisons
More useful head-to-heads from the same speaker class:
- KEF R5 Meta vs Revel F208
- KEF R5 Meta vs KEF R11 Meta
- KEF R5 Meta vs Revel F206
- KEF R5 Meta vs KEF R5
- JBL HDI-3600 vs PSB Imagine T65
The Two Speakers In Full
KEF R5: $2,999/pair Discontinued
Pros: Slim three-way tower with the acoustic advantages of KEF’s coincident Uni-Q midrange/tweeter: horizontal and vertical off-axis responses track the direct sound smoothly, producing stable imaging and a well-behaved directivity index. Erin measured deep low-frequency reach for the cabinet width—77Hz F3 but 33Hz F10—and less than 1% harmonic distortion at 86dB. At 96dB it remains clean when high-passed, and its mild response deviations are suitable for equalization because the radiation pattern stays orderly.
Cons: The unusual gap between 77Hz F3 and 33Hz F10 indicates a gradual bass contour rather than flat deep-bass output; a subwoofer and roughly 80Hz high-pass are recommended for high-level playback. Erin measured a minimum near 3.5 ohms around 150Hz, although most of the curve remains above 4 ohms, so amplifier quality still matters. Sensitivity is approximately 86dB/2.83V/1m. At 102dB, compression reaches roughly 1dB around 150Hz, showing the limits of the twin 5.25-inch woofers. This original model lacks the Meta version’s MAT rear-wave absorption. Discontinued.
Full KEF R5 review and specifications →
| Bass Extension (-10dB) | 33Hz (measured, Erin's Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 77Hz (measured, Erin's Audio Corner) |
| Dimensions | 40.4"H x 6.9"W x 13.5"D |
| Discontinued | Yes |
| Drivers | 1" aluminum tweeter coaxial with 5" midrange; dual 5.25" woofers |
| Impedance | Approximately 3.5 ohms minimum near 150Hz (measured, Erin's Audio Corner) |
| Sensitivity | Approximately 86dB/2.83V/1m (measured, Erin's Audio Corner) |
| Weight | 59.5 lb each |
| Woofer Cabinet | ported, rear |
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JBL HDI-3600: $3800 Audioadvice
Pros: CEA2034 spinorama shows a fairly even on-axis response and flat overall frequency response, with high 90dB sensitivity and very low distortion through the midrange. Triple 6.5” Advanced Aluminum Matrix woofers and a 1” compression driver in JBL’s HDI waveguide.
Cons: A wide shelving-down above 2kHz affects the in-room response, and vertical dispersion is a bigger issue than horizontal - the reviewer noted the dip is wider here than on the smaller HDI-1600, making it more audible. Narrow vertical sweet spot means careful listener-height positioning matters more than usual.
Full JBL HDI-3600 review and specifications →
| Bass Extension (-10dB) | 62Hz - the on-axis curve also shows an unusual step/dip around 40-55Hz that may be a near-field-scan artifact for this tower (measured, Audio Science Review) |
|---|---|
| Bass Extension (-3dB) | 78Hz - the on-axis curve also shows an unusual step/dip around 40-55Hz that may be a near-field-scan artifact for this tower (measured, Audio Science Review) |
| Dimensions | 40.5"H x 10.2"W x 13.5"D (1029 x 260 x 343 mm) |
| Drivers | 2410H-2 1" compression driver, 3x 6.5" Advanced Aluminum Matrix woofers |
| Frequency Response | 38Hz - 30kHz (+/-3dB) (Manufacturer specified) |
| Impedance | 4 ohms nominal |
| Sensitivity | 89.5dB (2.83V/1m, measured, Audio Science Review) |
| Weight | 61.7 lbs / 28 kg each |
| Woofer Cabinet | ported, dual rear-firing |
As an eBay Partner, we may be compensated if you make a purchase.
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- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons