Short answer: the Funk Audio Ultra 24.0 on measured sound quality, the Rythmik F18 on price. The Funk Audio Ultra 24.0 ranks #11 of 110 subwoofers at $9761.14. The Rythmik F18 ranks #69 at $2344, $7417.14 cheaper.
What the Rythmik F18 offers: Independent CEA-2010 testing records 106.2 dB at 20 Hz and 119.5 dB through 40-80 Hz. The sealed enclosure with 18” (457mm) driver has the headroom for demanding film bass in a large room. Watch for: The 520.7H x 520.7W x 533.4D mm cabinet and 52.2 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 Funk Audio Ultra 24.0 offers: Published CEA-2010 specifications list 120.0 dB at 20 Hz and 127.9 dB through 40-80 Hz. The sealed enclosure with 24” (610mm) driver has the headroom for demanding film bass in a large room. Watch for: The 787.4H x 660.4W x 609.6D mm cabinet and 135 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.
Buy the Rythmik F18 when the price outweighs sound quality for you, and the Funk Audio Ultra 24.0 when sound quality outweighs the price instead.
Want more options? Browse the full Subwoofers rankings.
Specifications Side By Side
| Rythmik F18 | Funk Audio Ultra 24.0 | |
|---|---|---|
| Price | $1,850 | $9,761.14 |
| Ranked | #69 of 110 in Large Home Subwoofers (Over 75 lbs) | #11 of 110 in Large Home Subwoofers (Over 75 lbs) |
| Enclosure | sealed | sealed |
| Output SPL at 10 Hz | 93.7 dB | 101.0 dB |
| Output SPL at 12.5 Hz | 97.4 dB | 104.9 dB |
| Output SPL at 15 Hz | 102.0 dB | 111.8 dB |
| Output SPL at 20 Hz | 106.2 dB | 120.0 dB |
| Output SPL at 25 Hz | 110.9 dB | 122.0 dB |
| Output SPL at 31.5 Hz | 114.3 dB | 123.0 dB |
| Output SPL at 40 Hz | 117.1 dB | 127.1 dB |
| Output SPL at 50 Hz | 119.1 dB | 129.9 dB |
| Output SPL at 63 Hz | 120.5 dB | 127.6 dB |
| Output SPL at 80 Hz | 121.2 dB | 127.0 dB |
| Output SPL at 100 Hz | 121.4 dB | 128.2 dB |
| Output SPL at 125 Hz | 121.4 dB | - |
| CEA-2010-A Average (40-80Hz) | 119.5 dB | 127.9 dB |
| Dimensions | 20.5"H x 20.5"W x 21"D (520.7 x 520.7 x 533.4 mm) | 31"H x 26"W x 24"D (787.4 x 660.4 x 609.6 mm) |
| Weight | 115.1 lbs (52.2 kg) | 297.6 lbs (135 kg) |
| Warranty | 5/3 | 3 |
| Cabinet Color | black | wood, custom |
| Country | United States | Canada |
| Measurement Source | Data-bass | Manufacturer |
| Drivers | 18" (457mm) driver | 24" (610mm) driver |
Related Speaker Comparisons
More top alternatives to Funk Audio Ultra 24.0:
- Funk Audio Ultra 24.0 vs JTR Speakers Captivator S2
- Funk Audio Ultra 24.0 vs Power Sound Audio (PSA) V3600I
- Funk Audio Custom 21.0 vs Funk Audio Ultra 24.0
- JTR Speakers Growler (2015) vs Funk Audio Ultra 24.0
- Harbinger V2218S vs Funk Audio Ultra 24.0
Prices on this page were last checked September 16, 2026 at 12:41 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
Rythmik F18: $1,850 Rythmik Audio eBay
Pros: Independent CEA-2010 testing records 106.2 dB at 20 Hz and 119.5 dB through 40-80 Hz. The sealed enclosure with 18” (457mm) driver has the headroom for demanding film bass in a large room.
Cons: The 520.7H x 520.7W x 533.4D mm cabinet and 52.2 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.
Full Rythmik F18 review and specifications →
| CEA-2010-A Average (40-80Hz) | 119.5 dB |
|---|---|
| Cabinet Color | black |
| Country | United States |
| Dimensions | 20.5"H x 20.5"W x 21"D (520.7 x 520.7 x 533.4 mm) |
| Drivers | 18" (457mm) driver |
| Enclosure | sealed |
| Measurement Source | Data-bass |
| Output SPL at 10 Hz | 93.7 dB |
| Output SPL at 12.5 Hz | 97.4 dB |
| Output SPL at 15 Hz | 102.0 dB |
| Output SPL at 20 Hz | 106.2 dB |
| Output SPL at 25 Hz | 110.9 dB |
| Output SPL at 31.5 Hz | 114.3 dB |
| Output SPL at 40 Hz | 117.1 dB |
| Output SPL at 50 Hz | 119.1 dB |
| Output SPL at 63 Hz | 120.5 dB |
| Output SPL at 80 Hz | 121.2 dB |
| Output SPL at 100 Hz | 121.4 dB |
| Output SPL at 125 Hz | 121.4 dB |
| Warranty | 5/3 |
| Weight | 115.1 lbs (52.2 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Independently measured by Data-bass; the published figures above come from this ASR subwoofer measurement thread.
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Funk Audio Ultra 24.0: $9,761.14 eBay
Pros: Published CEA-2010 specifications list 120.0 dB at 20 Hz and 127.9 dB through 40-80 Hz. The sealed enclosure with 24” (610mm) driver has the headroom for demanding film bass in a large room.
Cons: The 787.4H x 660.4W x 609.6D mm cabinet and 135 kg mass make this a serious placement and moving commitment. A sealed cabinet still needs careful placement and calibration to avoid room-mode peaks.
Full Funk Audio Ultra 24.0 review and specifications →
| CEA-2010-A Average (40-80Hz) | 127.9 dB |
|---|---|
| Cabinet Color | wood, custom |
| Country | Canada |
| Dimensions | 31"H x 26"W x 24"D (787.4 x 660.4 x 609.6 mm) |
| Drivers | 24" (610mm) driver |
| Enclosure | sealed |
| Measurement Source | Manufacturer |
| Output SPL at 10 Hz | 101.0 dB |
| Output SPL at 12.5 Hz | 104.9 dB |
| Output SPL at 15 Hz | 111.8 dB |
| Output SPL at 20 Hz | 120.0 dB |
| Output SPL at 25 Hz | 122.0 dB |
| Output SPL at 31.5 Hz | 123.0 dB |
| Output SPL at 40 Hz | 127.1 dB |
| Output SPL at 50 Hz | 129.9 dB |
| Output SPL at 63 Hz | 127.6 dB |
| Output SPL at 80 Hz | 127.0 dB |
| Output SPL at 100 Hz | 128.2 dB |
| Warranty | 3 |
| Weight | 297.6 lbs (135 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- These figures are manufacturer-specified rather than independently measured.
- Head-to-Head Comparisons
- Funk Audio Ultra 24.0 vs Funk Audio Custom 21.0
- Funk Audio Ultra 24.0 vs Power Sound Audio (PSA) V3600I
- Funk Audio Ultra 24.0 vs JTR Speakers Captivator S2
- Funk Audio Ultra 24.0 vs JTR Speakers Growler (2015)
- Funk Audio Ultra 24.0 vs Harbinger V2218S
- Funk Audio Ultra 24.0 vs Funk Audio Classic 18.0
- Funk Audio Ultra 24.0 vs Monoprice Monolith 16 THX Ultra
- Funk Audio Ultra 24.0 vs Rythmik FV25HP
- See all 17 comparisons