JBL 305P MKII vs Sigberg Audio SBS.1

Last updated: August 25, 2026

Short answer: the JBL 305P MKII. It ranks #11 of 64 powered bookshelf speakers by sound quality at $319; the Sigberg Audio SBS.1 ranks #37 and costs $2500, so there is not much of a tradeoff to weigh.

What the JBL 305P MKII offers: A fantastic value in studio monitors. Extremely close to the Focal Alpha 50 EVO, almost indistinguishable. Surprisingly deep and wide soundstage. Good horizontal dispersion (~70 degrees). Has a proper limiter that controls output cleanly rather than crudely cutting bass, and holds up well under sustained loud playback with minimal thermal compression. Watch for: Possible slight hissing from the amps at low levels. Rear ported, can be an issue close to walls. A port resonance around 1.6kHz is audible and distracting on some tracks. Midrange is somewhat scooped rather than flat for a studio monitor, and treble runs about 1.5dB hot - Erin’s Audio Corner recommends using the -2dB treble shelf switch. Vertical dispersion narrows around the crossover, so try to stay within about 10 degrees of the tweeter axis.

What the Sigberg Audio SBS.1 offers: Its 6.26 Spinorama preference score with a perfect subwoofer is the appropriate bass-normalized result because the SBS.1 is designed as a system with companion subwoofers, not for standalone use. That score exceeds the Manta’s 5.91, supported by better on-axis linearity and in-room smoothness above the subwoofer range. Distinctive 4-way coaxial design with dual 5.5” midbass drivers flanking a coincident 1” tweeter for time-aligned output. Active 3-channel Hypex nCore Class D amplification (350W per speaker) with a 9-band parametric EQ and factory presets. Watch for: Its 6.26 preference score with a perfect subwoofer trails the SBS Gen 2’s 6.74, and it has the widest listening-window deviation of the three Sigberg systems. Discontinued and sold out, replaced by the SBS Gen 2.

Buy the JBL 305P MKII. It ranks higher for sound quality than the Sigberg Audio SBS.1 and costs less, so there is no real case for the other one.

JBL 305P MKII vs Sigberg Audio SBS.1

Specifications Side By Side

JBL 305P MKII Sigberg Audio SBS.1
Price$319.00$2,500.00 2023 listing, per speaker; requires a separate subwoofer, Discontinued
Ranked#11 of 64 in Medium Size Powered Bookshelf Speakers#37 of 64 in Medium Size Powered Bookshelf Speakers
Dimensions11.7"H x 7.3"W x 9.1"D (297.2 x 185.4 x 231.1 mm)16.1"H x 7.5"W x 9.1"D (410 x 190 x 230 mm)
Frequency Response49 Hz - 20 kHz (+-3 dB) (Manufacturer specified)-
Bass Extension (-3dB)50Hz (measured, Erin’s Audio Corner)18Hz (manufacturer, with companion subwoofers)
Bass Extension (-10dB)43Hz (measured, Erin’s Audio Corner)-
InputsXLR, TRSXLR, RCA, Optical, Coaxial/SPDIF, AES
Weight10.4 lbs / 4.7 kg each20.9 lbs / 9.5 kg each
Drivers5" (127mm) woofer2x 5.5" midbass, 1" coaxial silk dome tweeter
AppNoNo
BluetoothNoNo
EQYes (Room adjustment)Yes (9-band parametric, factory presets)
Output Power81w Per Speaker350W per speaker
Sensitivity91.1dB (measured at 0.3V/1m, Erin’s Audio Corner)-
Enclosure-sealed
Max SPL-116dB
DSP-Yes
Country-Norway
Measurement Source-Manufacturer
Discontinued-Yes

More useful head-to-heads from the same speaker class:

Prices on this page were last checked August 25, 2026 at 6:19 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

JBL 305P MKII: $319.00 Amazon eBay

JBL 305P MKII ranking card

Pros: A fantastic value in studio monitors. Extremely close to the Focal Alpha 50 EVO, almost indistinguishable. Surprisingly deep and wide soundstage. Good horizontal dispersion (~70 degrees). Has a proper limiter that controls output cleanly rather than crudely cutting bass, and holds up well under sustained loud playback with minimal thermal compression.

Cons: Possible slight hissing from the amps at low levels. Rear ported, can be an issue close to walls. A port resonance around 1.6kHz is audible and distracting on some tracks. Midrange is somewhat scooped rather than flat for a studio monitor, and treble runs about 1.5dB hot - Erin’s Audio Corner recommends using the -2dB treble shelf switch. Vertical dispersion narrows around the crossover, so try to stay within about 10 degrees of the tweeter axis.

AppNo
Bass Extension (-10dB)43Hz (measured, Erin's Audio Corner)
Bass Extension (-3dB)50Hz (measured, Erin's Audio Corner)
BluetoothNo
Dimensions11.7"H x 7.3"W x 9.1"D (297.2 x 185.4 x 231.1 mm)
Drivers5" (127mm) woofer
EQYes (Room adjustment)
Frequency Response49 Hz - 20 kHz (+-3 dB) (Manufacturer specified)
InputsXLR, TRS
Output Power81w Per Speaker
Sensitivity91.1dB (measured at 0.3V/1m, Erin's Audio Corner)
Weight10.4 lbs / 4.7 kg each

Sigberg Audio SBS.1: $2,500.00 2023 listing, per speaker; requires a separate subwoofer, Discontinued eBay

Sigberg Audio SBS.1 ranking card

Pros: Its 6.26 Spinorama preference score with a perfect subwoofer is the appropriate bass-normalized result because the SBS.1 is designed as a system with companion subwoofers, not for standalone use. That score exceeds the Manta’s 5.91, supported by better on-axis linearity and in-room smoothness above the subwoofer range. Distinctive 4-way coaxial design with dual 5.5” midbass drivers flanking a coincident 1” tweeter for time-aligned output. Active 3-channel Hypex nCore Class D amplification (350W per speaker) with a 9-band parametric EQ and factory presets.

Cons: Its 6.26 preference score with a perfect subwoofer trails the SBS Gen 2’s 6.74, and it has the widest listening-window deviation of the three Sigberg systems. Discontinued and sold out, replaced by the SBS Gen 2. Discontinued.

AppNo
Bass Extension (-3dB)18Hz (manufacturer, with companion subwoofers)
BluetoothNo
CountryNorway
DSPYes
Dimensions16.1"H x 7.5"W x 9.1"D (410 x 190 x 230 mm)
DiscontinuedYes
Drivers2x 5.5" midbass, 1" coaxial silk dome tweeter
EQYes (9-band parametric, factory presets)
Enclosuresealed
InputsXLR, RCA, Optical, Coaxial/SPDIF, AES
Max SPL116dB
Measurement SourceManufacturer
Output Power350W per speaker
Weight20.9 lbs / 9.5 kg each