HSU Research ULS-15 MK2 vs Rythmik F12

Last updated: September 19, 2026

Short answer: these are two serious sealed subwoofers with different priorities: HSU brings a larger 15-inch platform, while Rythmik uses servo control in a compact 12-inch design. Both are aimed at tight, accurate bass rather than the maximum low-end output of a ported enclosure.

HSU Research ULS-15 MK2 vs Rythmik F12

The case for the HSU Research ULS-15 MK2: Sealed design delivers tight, accurate bass with low bloat.

What the Rythmik F12 gets right: Sealed 12-inch servo with 370W RMS offers excellent value.

Buy the HSU Research ULS-15 MK2 if you want the larger sealed driver platform for deep, controlled bass.

Buy the Rythmik F12 if servo-controlled bass and a compact sealed cabinet suit your system better.

Looking for alternatives? See the complete Subwoofers rankings.

Buy the HSU Research ULS-15 MK2 at HSU Research ($999.00) →Buy the Rythmik F12 at Rythmik Audio ($1,439) →

Specifications Side By Side

HSU Research ULS-15 MK2 Rythmik F12
Price$1,035$1,120
Ranked#3 of 145 in Medium Home Subwoofers (30-75 lbs)#20 of 145 in Medium Home Subwoofers (30-75 lbs)
Enclosuresealedsealed
Output SPL at 12.5 Hz93.7 dB-
Output SPL at 15 Hz98.0 dB-
Output SPL at 20 Hz102.4 dB103.6 dB
Output SPL at 25 Hz107.7 dB106.7 dB
Output SPL at 31.5 Hz113.4 dB113.5 dB
Output SPL at 40 Hz118.3 dB118.3 dB
Output SPL at 50 Hz120.8 dB119.1 dB
Output SPL at 63 Hz121.2 dB120.4 dB
Output SPL at 80 Hz121.1 dB119.6 dB
Output SPL at 100 Hz120.7 dB-
Output SPL at 125 Hz120.7 dB-
CEA-2010-A Average (40-80Hz)120.3 dB119.3 dB
Dimensions19"H x 18"W x 19.5"D (482.6 x 457.2 x 495.3 mm)15.7"H x 15.7"W x 17"D (400.0 x 400.0 x 431.8 mm)
Weight65 lbs (29.5 kg)75 lbs (34.0 kg)
Warranty7/2(+3)5/3
Cabinet Colorblack, woodblack
CountryUnited StatesUnited States
Measurement SourceAudioholicsBrent Butterworth
Frequency Response20-200Hz, ±1dB14Hz extension
Amplifier Power600W RMS / 2000W peak370W RMS
Crossover Frequency30-90Hz adjustable-
Phase Control0°-180°-
FeaturesQ control, sealed subwoofer, EQ1/EQ2 modes-
Drivers15" (381mm) driver12" (305mm) driver
Output SPL at 16 Hz-101.0 dB
Inputs-XLR (2), RCA (line/LFE)
XLR Input-Yes
RCA Input-Yes
TRS Input-No
Optical Input-No
Coaxial Input-No
USB Input-No
HDMI Input-No
AES Input-No
Aux Input-No
Buy the HSU Research ULS-15 MK2 at HSU Research ($999.00) →Buy the Rythmik F12 at Rythmik Audio ($1,439) →

More top alternatives to HSU Research ULS-15 MK2:

Prices on this page were last checked September 23, 2026 at 11:24 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.

As an eBay Partner, we may be compensated if you make a purchase.

The Two Speakers In Full

HSU Research ULS-15 MK2: $1,035 HSU Research eBay

HSU Research ULS-15 MK2 ranking card

Pros: Sealed design delivers tight, accurate bass with low bloat. 600W BASH amplifier. 30% less expensive and 20 lbs lighter than predecessor. Easy integration with Q and EQ controls. Great value in the 15” sub market.

Notes: Price includes shipping

Full HSU Research ULS-15 MK2 review and specifications →

Amplifier Power600W RMS / 2000W peak
CEA-2010-A Average (40-80Hz)120.3 dB
Cabinet Colorblack, wood
CountryUnited States
Crossover Frequency30-90Hz adjustable
Dimensions19"H x 18"W x 19.5"D (482.6 x 457.2 x 495.3 mm)
Drivers15" (381mm) driver
Enclosuresealed
FeaturesQ control, sealed subwoofer, EQ1/EQ2 modes
Frequency Response20-200Hz, ±1dB
Measurement SourceAudioholics
Output SPL at 12.5 Hz93.7 dB
Output SPL at 15 Hz98.0 dB
Output SPL at 20 Hz102.4 dB
Output SPL at 25 Hz107.7 dB
Output SPL at 31.5 Hz113.4 dB
Output SPL at 40 Hz118.3 dB
Output SPL at 50 Hz120.8 dB
Output SPL at 63 Hz121.2 dB
Output SPL at 80 Hz121.1 dB
Output SPL at 100 Hz120.7 dB
Output SPL at 125 Hz120.7 dB
Phase Control0°-180°
Warranty7/2(+3)
Weight65 lbs (29.5 kg)
Check current price at HSU Research ($999.00) →Search eBay for HSU Research ULS-15 MK2 →

Rythmik F12: $1,120 Rythmik Audio eBay

Rythmik F12 ranking card

Pros: Sealed 12-inch servo with 370W RMS offers excellent value. Very musical and can disappear in small rooms. Digs to 14Hz with excellent build quality and well-braced cabinet.

Full Rythmik F12 review and specifications →

AES InputNo
Amplifier Power370W RMS
Aux InputNo
CEA-2010-A Average (40-80Hz)119.3 dB
Cabinet Colorblack
Coaxial InputNo
CountryUnited States
Dimensions15.7"H x 15.7"W x 17"D (400.0 x 400.0 x 431.8 mm)
Drivers12" (305mm) driver
Enclosuresealed
Frequency Response14Hz extension
HDMI InputNo
InputsXLR (2), RCA (line/LFE)
Measurement SourceBrent Butterworth
Optical InputNo
Output SPL at 16 Hz101.0 dB
Output SPL at 20 Hz103.6 dB
Output SPL at 25 Hz106.7 dB
Output SPL at 31.5 Hz113.5 dB
Output SPL at 40 Hz118.3 dB
Output SPL at 50 Hz119.1 dB
Output SPL at 63 Hz120.4 dB
Output SPL at 80 Hz119.6 dB
RCA InputYes
TRS InputNo
USB InputNo
Warranty5/3
Weight75 lbs (34.0 kg)
XLR InputYes
Check current price at Rythmik Audio ($1,439) →Search eBay for Rythmik F12 →