In this review, we will be comparing Nero DueVoce DualX8 and Varro PS250-BK, two Powered Subwoofer speakers from OSD and ELAC. Being Powered subwoofers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them. Let's have a brief look at the main features of OSD Nero DueVoce DualX8 and ELAC Varro PS250-BK first before getting into our more detailed comparison.
The sections below take each area in turn: driver and amplifier, frequency response, physical size and connectivity.
Drivers
The efficiency of a subwoofer is directly proportional to the total radiating are squared hence the woofer quantity and diameter.Both OSD Nero DueVoce DualX8and ELAC Varro PS250-BK have a single woofer setup however the OSD Nero DueVoce DualX8's woofer is 8-inch whereas the ELAC Varro PS250-BK features a 10-inch woofer.
Frequency Response
Nero DueVoce DualX8 has a frequency range of 17-165 Hz whereas Varro PS250-BK has a frequency range of 27-150 Hz. With a minimum frequency of 17Hz, the Nero DueVoce DualX8 can go significantly deeper on the low side and provide stronger bass compared to the Varro PS250-BK's min frequency of 27Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Subwoofer class in our database.
Low Frequency
Subwoofer Speakers
High Frequency
Subwoofer Speakers
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare OSD Nero DueVoce DualX8's and ELAC Varro PS250-BK's external dimensions. OSD Nero DueVoce DualX8 has external dimensions of 311.2 x 265.1 x 333.4mm () whereas ELAC Varro PS250-BK has external dimensions of 381.0 x 361.0 x 361.0mm (15inch x 14-3/16inch x 14-3/16inch).
ELAC Varro PS250-BK is clearly the larger of the two speakers. Its body is 95.9mm wider, 69.8mm taller and 27.6mm deeper than OSD Nero DueVoce DualX8.
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the OSD Nero DueVoce DualX8 is approximately 883.8cm2 / 137.0inch2 and base area of the ELAC Varro PS250-BK is approximately 1303.2cm2 / 202.0inch2. The Nero DueVoce DualX8 requires 32% less surface area than the Varro PS250-BK which gives it a small advantage on placement in tight spaces.
Weight Comparison The weight of a subwoofer may become an important factor if you need to move and reposition the unit often to find the optimal positioning, also known as 'Subwoofer Crawling'. The OSD Nero DueVoce DualX8 weighs 7.80kg / 17.2lbs and the ELAC Varro PS250-BK weighs 16.44kg / 36.2lbs. This makes the Varro PS250-BK 111% heavier than the Nero DueVoce DualX8.
Here is a comparison of how Nero DueVoce DualX8 and Varro PS250-BK's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
 Low Frequency Response |
17 Hz
vs
27 Hz
|
Generates deeper bass |
 High Frequency Response |
165 Hz
vs
150 Hz
|
Generates higher frequency |
 Height |
311mm
vs
381mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
883cm2
vs
1303cm2
|
Takes less floor space |
 Price per pair* |
300USD
vs
649USD
|
costs less (*prices may change depending on the seller, location and time) |
| Woofer Size |
10 inches
vs
8 inches
|
Larger woofer |
 App-Based Control |
iOS,Android
vs
None
|
Control the speaker via an app |
Size, drawn to scale
Both subwoofers and both views share one scale, so everything here is directly comparable. Hover a box for its dimensions.
One scale for both, standing on the same floor and pushed back to the same wall, so the bigger one visibly takes more of the room.
ELAC Varro PS250-BK needs about 47% more floor area. ELAC Varro PS250-BK stands 28mm further into the room. ELAC Varro PS250-BK is 70mm taller.
| General |
OSD Nero DueVoce DualX8 |
ELAC Varro PS250-BK |
| Brand |
OSD |
ELAC |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Frequency Response |
17-165 Hz |
27-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
130-watt RMS |
250-watt RMS |
| Watts Peak (Max) |
300-watt RMS |
500-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
10" |
| Woofer Composition |
|
Treated paper |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
n/a |
bottom |
Physical Specs |
|
|
| Height |
311.2mm (12.3") |
381.0mm (15") |
| Width |
265.1mm (10.4") |
361.0mm (14.2") |
| Depth |
333.4mm (13.1") |
361.0mm (14.2") |
| Weight |
7.80kg (17.2lbs) |
16.44kg (36.2lbs) |
| Enclosure |
|
Bass Reflex |
| Finish |
n/a |
MDF |
| Available Colors |
n/a |
Black |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| USB Port |
n/a |
USB-A port for firmware updates |
Other |
|
|
| Parts Warranty |
2 Years |
1 year |
| Labor Warranty |
2 Years |
1 year |
A passive radiator subwoofer against a ported one. That is the most consequential line on this page: it decides how the bass rolls off, how it behaves in a small room, and how much output you get for the size of the box.
| Area | Better | Why |
|---|
| Bass depth | A | OSD Nero DueVoce DualX8 goes deeper - 17Hz against 27Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | B | ELAC Varro PS250-BK has the bigger amplifier - 250W against 130W RMS, about 2.8dB more on tap. In a large room that is headroom before the DSP starts limiting. |
| Driver area | B | ELAC Varro PS250-BK moves more air: 10" against 8" is 1.56x the cone area, not the 1.25x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | OSD Nero DueVoce DualX8 is passive radiator - a passive radiator behaves like a port without the pipe noise, and suits a slim cabinet; ELAC Varro PS250-BK is ported - a ported box gives more output low down for its size, at the cost of a steeper roll-off below tuning. Neither is better in the abstract; ported tends to suit films and sealed tends to suit music, and both generalisations have exceptions. |
| Cabinet size | depends | OSD Nero DueVoce DualX8 is about 45% smaller by volume. In a subwoofer that is a real trade rather than a preference: box volume is how you get output low down without a bigger amplifier. |
| Warranty | A | OSD Nero DueVoce DualX8 carries 2 years on parts against 1 years. A subwoofer amplifier works harder than anything else in the system, so this is not a throwaway line. |
| Price | A | OSD Nero DueVoce DualX8 costs less - $300 against $649, about 54% less. |
A OSD Nero DueVoce DualX8 B ELAC Varro PS250-BK
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both subwoofers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Neither runs away with it - they trade advantages. Let your room size and where the box can actually stand settle it. Two small subwoofers beat one big one in most rooms - a pair evens out the room modes in a way no single box can, whatever its specs. At $300 each, two OSD Nero DueVoce DualX8 cost about $600 against $649 for one of the other, which is worth a thought. If placement is the constraint - a corner, behind a sofa, under a desk - OSD Nero DueVoce DualX8 is the one that will actually go there, and a well-placed small subwoofer beats a badly-placed big one every time.
One thing outweighs everything above: where the subwoofer stands. Room modes can add or remove 10dB or more at a given seat, which is far larger than any difference on this page. Before spending more, try the sub in two or three positions - the crawl test, where you put it in the listening seat and crawl the room to find where the bass sounds best, costs nothing and usually beats an upgrade.