Short answer: the Ascend Acoustics Sierra Titan Tower. It ranks #45 of 228 floorstanding speakers by sound quality, rated 4.4/5, at $2,998; the JBL HDI-3600 ranks #63, rated 4.3/5, and costs $3,800, so there is not much of a tradeoff to weigh.
The Ascend Acoustics Sierra Titan Tower is the more accurate, deeper-bass choice. A SEAS Titan dome tweeter and dual 5.25 inch long throw woofers in a bamboo V-LAM tower reach a measured 58.6Hz extension point at a more accessible price than Ascend’s ribbon tweeter ELX line. Its measured preference score, a predictor of how neutral it sounds, is 6.05 against 4.64 for the JBL HDI-3600. Its bass reaches about 58.6Hz before falling 3dB, against 78Hz for the JBL HDI-3600. The tradeoff: Its listening window response is the least smooth of Ascend’s measured towers, trailing the pricier Ascend Acoustics ELX Ribbon Tower.
Why pick the JBL HDI-3600: 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 JBL HDI-1600, making it more audible.
Buy the Ascend Acoustics Sierra Titan Tower. It is rated higher for sound quality than the JBL HDI-3600 and costs less, so only choose the other one for a particular feature it does better.
Looking for alternatives? See the complete Passive Home rankings.
A SEAS Titan dome tweeter and dual 5.25 inch long throw woofers in a bamboo V-LAM tower reach a measured 58.6Hz extension point at a more accessible price than Ascend’s ribbon tweeter ELX line.
Ascend Acoustics $2,998 eBay
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.
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Specifications Side By Side
| Ascend Acoustics Sierra Titan Tower | JBL HDI-3600 | |
|---|---|---|
| Price | $2,998 per pair | $3800 per pair |
| Ranked | #45 of 228 in Large Size Floorstanding Speakers | #63 of 228 in Large Size Floorstanding Speakers |
| Enclosure | ported | - |
| Drivers | SEAS Titan dome tweeter, 1x 5.25” midrange (sealed sub-chamber), 2x 5.25” mineral filled polypropylene woofers | 2410H-2 1” compression driver, 3x 6.5” Advanced Aluminum Matrix woofers |
| Dimensions | 43”H x 7.5”W x 10.5”D (1092 x 190 x 267 mm) | 40.5”H x 10.2”W x 13.5”D (1029 x 260 x 343 mm) |
| Weight | 45 lbs (20.4 kg) each | 61.7 lbs (28 kg) each |
| Sensitivity | 88dB @ 2.83V/1m in-room (manufacturer) | 89.5dB (2.83V/1m, measured, Audio Science Review) |
| Impedance | 8 ohms nominal | 4 ohms nominal |
| Power Handling | 300W continuous, 500W peak | - |
| Frequency Response | 32-27,000Hz typical in-room (manufacturer) | 38Hz - 30kHz (+/-3dB) (Manufacturer specified) |
| Bass Extension (-3dB) | 58.6Hz (measured, spinorama.org vendor data) | 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) | 34.6Hz (measured, spinorama.org vendor data) | 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) |
| Warranty | 7 years parts and labor | - |
| Country | United States | - |
| Spinorama Preference Score | 6.05 | 4.64 (spinorama.org) |
| Spinorama Preference Score with Perfect Sub | 8.00 | 6.95 (spinorama.org) |
| DIY Kit | No | No |
| Woofer Cabinet | - | ported, dual rear-firing |
Frequency Response Compared
Both speakers’ spinorama measurements, overlaid. A flatter line is more neutral: peaks sound forward or harsh, dips sound recessed. Each curve is shifted so its average from 300 Hz to 3 kHz sits at 0 dB, so loudness differences between the two are removed and only the shape is compared. The two were measured by different sources, so small differences, especially in the bass, can come from the measurement setup rather than the speakers.
Measurement data: Ascend Acoustics Sierra Titan Tower (measured by the manufacturer) and JBL HDI-3600 (measured by Audio Science Review), via spinorama.org.
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