JTR Speakers Captivator S2 vs BK Electronics Monolith-DF

Short answer: the JTR Speakers Captivator S2. It ranks #9 of 110 subwoofers by sound quality at $3995; the BK Electronics Monolith-DF ranks #107 and costs $8995, which makes this an easy call rather than a real tradeoff.

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 BK Electronics Monolith-DF offers: Independent CEA-2010 testing records 102.0 dB at 20 Hz and 108.4 dB through 40-80 Hz. The ported, bottom enclosure with 12” (305mm) driver with ported design delivers substantial upper-bass output for movie effects and music. Watch for: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority. The 603.8H x 539.8W x 419.9D mm cabinet and 46.8 kg mass still require deliberate placement and calibration.

Buy the JTR Speakers Captivator S2. It ranks higher for sound quality than the BK Electronics Monolith-DF and costs less, so the other one has nothing left to offer.

The BK Electronics Monolith-DF is not a sound-quality pick. It sits near the bottom of the 110 subwoofers; there are better options higher up.

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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BK Electronics Monolith-DF: $8995 eBay

Pros: Independent CEA-2010 testing records 102.0 dB at 20 Hz and 108.4 dB through 40-80 Hz. The ported, bottom enclosure with 12” (305mm) driver with ported design delivers substantial upper-bass output for movie effects and music.

Cons: Deep-bass output is more limited than the strong 40-80 Hz result suggests, so it is not the right choice when the lowest movie effects are the priority. The 603.8H x 539.8W x 419.9D mm cabinet and 46.8 kg mass still require deliberate placement and calibration.

Full BK Electronics Monolith-DF review and specifications →

CEA-2010-A Average (40-80Hz)	108.4 dB
Cabinet Color	black, wood
Country	United Kingdom
Dimensions	23.8"H x 21.3"W x 16.5"D (603.8 x 539.8 x 419.9 mm)
Drivers	12" (305mm) driver with ported design
Enclosure	ported, bottom
Measurement Source	Ilkka Rissanen
Output SPL at 15 Hz	91.3 dB
Output SPL at 20 Hz	102.0 dB
Output SPL at 25 Hz	106.4 dB
Output SPL at 31.5 Hz	108.3 dB
Output SPL at 40 Hz	108.6 dB
Output SPL at 50 Hz	108.7 dB
Output SPL at 63 Hz	108.6 dB
Output SPL at 80 Hz	107.7 dB
Warranty	2
Weight	103.2 lbs (46.8 kg)

• Links
  • BK Electronics Monolith-DF Website
• Reviews, Comparisons and Sound Samples
  • Independently measured by Ilkka Rissanen; the published figures above come from this ASR subwoofer measurement thread.
• Head-to-Head Comparisons
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