JTR Speakers Captivator S2 vs JBL 4645C

Short answer: the JTR Speakers Captivator S2. It ranks #9 of 110 subwoofers by sound quality at $3995; the JBL 4645C ranks #24 and costs $4999, so there is not much of a tradeoff to weigh.

What the JTR Speakers Captivator S2 offers: Independent CEA-2010 testing records 115.1 dB at 20 Hz and 129.4 dB through 40-80 Hz. The sealed enclosure with 2x 18” (457mm) drivers has the headroom for demanding film bass in a large room. Watch for: The 1016.0H x 533.4W x 457.2D mm cabinet and 99.8 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.

What the JBL 4645C offers: Independent CEA-2010 testing records 98.9 dB at 20 Hz and 127.3 dB through 40-80 Hz. The ported, front enclosure with 18” (457mm) driver is best suited to upper-bass support in a modest room. Watch for: Deep-bass output is limited relative to its midbass result, so it is not the right choice for the lowest movie effects. The 1009.6H x 673.1W x 450.8D mm cabinet and 62.6 kg mass still need deliberate placement and calibration.

Buy the JTR Speakers Captivator S2. It ranks higher for sound quality than the JBL 4645C and costs less, so there is no real case for the other one.

Still deciding? The full Subwoofers rankings cover every ranked option.

Specifications Side By Side

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The Two Speakers In Full

JTR Speakers Captivator S2: $3995 eBay

Pros: Independent CEA-2010 testing records 115.1 dB at 20 Hz and 129.4 dB through 40-80 Hz. The sealed enclosure with 2x 18” (457mm) drivers has the headroom for demanding film bass in a large room.

Cons: The 1016.0H x 533.4W x 457.2D mm cabinet and 99.8 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.

Notes: Replaced by “RS2”

Full JTR Speakers Captivator S2 review and specifications →

CEA-2010-A Average (40-80Hz)	129.4 dB
Country	United States
Dimensions	40"H x 21"W x 18"D (1016.0 x 533.4 x 457.2 mm)
Drivers	2x 18" (457mm) drivers
Enclosure	sealed
Measurement Source	Data-bass
Output SPL at 10 Hz	100.3 dB
Output SPL at 12.5 Hz	103.3 dB
Output SPL at 15 Hz	108.7 dB
Output SPL at 20 Hz	115.1 dB
Output SPL at 25 Hz	119.7 dB
Output SPL at 31.5 Hz	124.8 dB
Output SPL at 40 Hz	129.3 dB
Output SPL at 50 Hz	130.3 dB
Output SPL at 63 Hz	129.4 dB
Output SPL at 80 Hz	128.5 dB
Output SPL at 100 Hz	128.1 dB
Output SPL at 125 Hz	128.0 dB
Warranty	5/3
Weight	220 lbs (99.8 kg)

• Links
  • JTR Speakers Captivator S2 Website
• Reviews, Comparisons and Sound Samples
  • Independently measured by Data-bass; the published figures above come from this ASR subwoofer measurement thread.
• Head-to-Head Comparisons
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  • See all 23 comparisons

JBL 4645C: $4999 Passive eBay

Pros: Independent CEA-2010 testing records 98.9 dB at 20 Hz and 127.3 dB through 40-80 Hz. The ported, front enclosure with 18” (457mm) driver is best suited to upper-bass support in a modest room.

Cons: Deep-bass output is limited relative to its midbass result, so it is not the right choice for the lowest movie effects. The 1009.6H x 673.1W x 450.8D mm cabinet and 62.6 kg mass still need deliberate placement and calibration.

Full JBL 4645C review and specifications →

CEA-2010-A Average (40-80Hz)	127.3 dB
Cabinet Color	black
Country	United States
Dimensions	39.7"H x 26.5"W x 17.7"D (1009.6 x 673.1 x 450.8 mm)
Drivers	18" (457mm) driver
Enclosure	ported, front
Measurement Source	Data-bass
Output SPL at 20 Hz	98.9 dB
Output SPL at 25 Hz	114.0 dB
Output SPL at 31.5 Hz	118.7 dB
Output SPL at 40 Hz	122.0 dB
Output SPL at 50 Hz	123.7 dB
Output SPL at 63 Hz	129.7 dB
Output SPL at 80 Hz	133.9 dB
Output SPL at 100 Hz	135.1 dB
Output SPL at 125 Hz	135.8 dB
Passive	Yes
Warranty	5/3/2
Weight	138 lbs (62.6 kg)

• Links
  • JBL 4645C Website
• Reviews, Comparisons and Sound Samples
  • Independently measured by Data-bass; the published figures above come from this ASR subwoofer measurement thread.
• Head-to-Head Comparisons
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  • JBL 4645C vs WW Speaker Cabinets X21 - B&C 21DS115-4
  • JBL 4645C vs HSU Research VTF-3 MK5 HP