Short answer: the L-Acoustics SYVA-low+top. It ranks #1 of 13 line array and installation pa speakers by sound quality (rated 4.4/5); the Alcons Audio QR24 ranks #6 (rated 4.0/5).
What the L-Acoustics SYVA-low+top does well: Vendor Spinorama data gives preference scores of 6.05 standalone and 8.11 with an ideal subwoofer, the best in this ranking. The catch: A passive system that needs L-Acoustics amplified controllers (LA4X, LA12X or LA8).
The case for the Alcons Audio QR24: High-quality manufacturer measurements give preference scores of 4.38 standalone and 7.25 with an ideal subwoofer, with a tight 1.4dB reference band and 0.279 listening-window deviation. The tradeoff: Bass drops quickly below about 70Hz, so a subwoofer is needed for full-range music.
Buy the L-Acoustics SYVA-low+top. It is rated higher for sound quality than the Alcons Audio QR24.
Want more options? Browse the full PA & Live Sound rankings.
Specifications Side By Side
| L-Acoustics SYVA-low+top | Alcons Audio QR24 | |
|---|---|---|
| Price | - | - |
| Ranked | #1 of 13 in Line Array and Installation PA Speakers | #6 of 13 in Line Array and Installation PA Speakers |
| Configuration | Passive 2-way line source with dual 12” low extension (SYVA plus SYVA Low) | Passive 2-way modular column (pro-ribbon) |
| Drivers | 6x 5” cone drivers and 3x 1.75” compression drivers (SYVA), dual 12” cone drivers (SYVA Low) | 2x 12” RBN1203 pro-ribbon drivers, 4x 6.5” neodymium woofers (vented) |
| Frequency Response | 40Hz - 20kHz (manufacturer specified) | 74Hz - 20kHz (±3dB, manufacturer specified) |
| Dimensions | 84.6”H x 13.1”W x 13.8”D (2150 x 334 x 350 mm) (measured stack) | 25.9”H x 9.8”W x 13.2”D (658 x 248 x 336 mm) |
| Inputs | Speakon (via L-Acoustics amplified controller) | - |
| Amplifier Power | Passive speaker; requires an L-Acoustics amplified controller (LA4X, LA12X or LA8) | Passive speaker; requires external amplification (Alcons Sentinel) |
| Cabinet Material | Baltic beech and birch plywood | - |
| Bass Extension (-3dB) | 50Hz (measured, vendor Spinorama data) | 71Hz (measured, vendor Spinorama data) |
| Coverage | 140° horizontal, about 25° vertical | 80° or 110° horizontal x 3.6° per module |
| Maximum SPL | 137dB (manufacturer specified) | 135dB peak (manufacturer specified) |
| DSP | No (passive; processing and protection come from the amplified controller) | No (passive) |
| Weight | 110.2 lbs (50 kg) | 48.5 lbs (22 kg) |
| Spinorama Preference Score | 6.05 | 4.38 |
| Spinorama Preference Score with Perfect Sub | 8.11 | 7.25 |
| Bluetooth | No | No |
| XLR Input | No | No |
| RCA Input | No | No |
| TRS Input | No | No |
| Optical Input | No | No |
| Coaxial Input | No | No |
| USB Input | No | No |
| HDMI Input | No | No |
| AES Input | No | No |
| Aux Input | No | No |
| Microphone Input | No | No |
| Guitar Input | No | No |
| Sensitivity | - | 109dB (200Hz - 10kHz) |
| Impedance | - | 8 ohms |
| Bass Extension (-10dB) | - | about 62.5Hz (measured, vendor Spinorama data) |
Related Speaker Comparisons
More worthwhile head-to-heads for L-Acoustics SYVA-low+top:
- L-Acoustics SYVA-low+top vs JBL CBT 1000 + CBT 1000E
- L-Acoustics SYVA-low+top vs JBL CBT 1000
- L-Acoustics SYVA-low+top vs Kling Freitag PIA M
- JBL CBT 1000 + CBT 1000E vs Alcons Audio QR24
- JBL CBT 1000 vs Alcons Audio QR24
Prices on this page were last checked September 26, 2026 at 11:14 PM 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
L-Acoustics SYVA-low+top Passive eBay
Pros: Vendor Spinorama data gives preference scores of 6.05 standalone and 8.11 with an ideal subwoofer, the best in this ranking. Pairing the SYVA line source with SYVA Low adds two 12-inch drivers, extending bass to about 50Hz (-3dB) and 137dB peak SPL. Listening-window narrow-band deviation is 0.188, and the 140° horizontal pattern covers wide rooms from one slim column. Measured bass extension of 50Hz (-3dB).
Cons: A passive system that needs L-Acoustics amplified controllers (LA4X, LA12X or LA8). The two-element stack is 2.15m tall and about 50kg, so it is an installed or touring system rather than a grab-and-go box. Vertical coverage is only about 25°, which suits seated audiences but limits use on steep or multi-tier rooms.
Full L-Acoustics SYVA-low+top review and specifications →
| AES Input | No |
|---|---|
| Amplifier Power | Passive speaker; requires an L-Acoustics amplified controller (LA4X, LA12X or LA8) |
| Aux Input | No |
| Bass Extension (-3dB) | 50Hz (measured, vendor Spinorama data) |
| Bluetooth | No |
| Cabinet Material | Baltic beech and birch plywood |
| Coaxial Input | No |
| Configuration | Passive 2-way line source with dual 12” low extension (SYVA plus SYVA Low) |
| Coverage | 140° horizontal, about 25° vertical |
| DSP | No (passive; processing and protection come from the amplified controller) |
| Dimensions | 84.6”H x 13.1”W x 13.8”D (2150 x 334 x 350 mm) (measured stack) |
| Drivers | 6x 5” cone drivers and 3x 1.75” compression drivers (SYVA), dual 12” cone drivers (SYVA Low) |
| Frequency Response | 40Hz - 20kHz (manufacturer specified) |
| Guitar Input | No |
| HDMI Input | No |
| Inputs | Speakon (via L-Acoustics amplified controller) |
| Maximum SPL | 137dB (manufacturer specified) |
| Microphone Input | No |
| Optical Input | No |
| RCA Input | No |
| Spinorama Preference Score | 6.05 |
| Spinorama Preference Score with Perfect Sub | 8.11 |
| TRS Input | No |
| USB Input | No |
| Weight | 110.2 lbs (50 kg) |
| XLR Input | No |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
Alcons Audio QR24 Passive eBay
Pros: High-quality manufacturer measurements give preference scores of 4.38 standalone and 7.25 with an ideal subwoofer, with a tight 1.4dB reference band and 0.279 listening-window deviation. Two 12-inch pro-ribbon drivers above four 6.5-inch woofers give 109dB sensitivity and a 135dB peak, and bass reaches 71Hz at -3dB. It works alone or stacked with more modules as a vertical array, in 80° or 110° horizontal versions. Measured bass extension of 71Hz (-3dB).
Cons: Bass drops quickly below about 70Hz, so a subwoofer is needed for full-range music. It needs Alcons Sentinel amplification for its presets, weighs 22kg, and is sold only through pro dealers with no published price.
Full Alcons Audio QR24 review and specifications →
| AES Input | No |
|---|---|
| Amplifier Power | Passive speaker; requires external amplification (Alcons Sentinel) |
| Aux Input | No |
| Bass Extension (-10dB) | about 62.5Hz (measured, vendor Spinorama data) |
| Bass Extension (-3dB) | 71Hz (measured, vendor Spinorama data) |
| Bluetooth | No |
| Coaxial Input | No |
| Configuration | Passive 2-way modular column (pro-ribbon) |
| Coverage | 80° or 110° horizontal x 3.6° per module |
| DSP | No (passive) |
| Dimensions | 25.9”H x 9.8”W x 13.2”D (658 x 248 x 336 mm) |
| Drivers | 2x 12” RBN1203 pro-ribbon drivers, 4x 6.5” neodymium woofers (vented) |
| Frequency Response | 74Hz - 20kHz (±3dB, manufacturer specified) |
| Guitar Input | No |
| HDMI Input | No |
| Impedance | 8 ohms |
| Maximum SPL | 135dB peak (manufacturer specified) |
| Microphone Input | No |
| Optical Input | No |
| RCA Input | No |
| Sensitivity | 109dB (200Hz - 10kHz) |
| Spinorama Preference Score | 4.38 |
| Spinorama Preference Score with Perfect Sub | 7.25 |
| TRS Input | No |
| USB Input | No |
| Weight | 48.5 lbs (22 kg) |
| XLR Input | No |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons