In this review, we will be comparing A120P and ProSub 800, two Powered Subwoofer speakers from JBL and Definitive Technology. 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 JBL Stage A120P and Definitive ProSub 800 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 JBL Stage A120Pand Definitive ProSub 800 have a single woofer setup however the JBL Stage A120P's woofer is 12-inch whereas the Definitive ProSub 800 features a 8-inch woofer.
Frequency Response
A120P has a frequency range of 32-150 Hz whereas ProSub 800 has a frequency range of 20-150 Hz. With a minimum frequency of 20Hz, the ProSub 800 can go significantly deeper on the low side and provide stronger bass compared to the A120P's min frequency of 32Hz.
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
Cabinet Type
The JBL Stage A120P has a Bass reflex type cabinet. On the other hand the Definitive ProSub 800 have Passive Radiator type enclosure. Passive Radiator type subwoofers sports a non-powered cone that moves in response to the main woofer to move air out in order to generate stronger bass in a smaller body compared to ported or sealed designs.
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 JBL Stage A120P's and Definitive ProSub 800's external dimensions. JBL Stage A120P has external dimensions of 415.0 x 393.0 x 475.0mm (16-5/16 x 15-7/16 x 18-11/16inch) whereas Definitive ProSub 800 has external dimensions of 328.0 x 262.0 x 423.0mm (12-7/8 x 10-5/16 x 16-5/8inch).
JBL Stage A120P is clearly the larger of the two speakers. Its body is 131mm wider, 87mm taller and 52mm deeper than Definitive ProSub 800.
Below you can see the front view size comparison of JBL Stage A120P and Definitive ProSub 800 in scale.
Comparison image of JBL Stage A120P and Definitive ProSub 800 Size and External Dimensions
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 JBL Stage A120P is approximately 1866.8cm2 / 289.4inch2 and base area of the Definitive ProSub 800 is approximately 1108.3cm2 / 171.8inch2. The A120P requires 68% more surface area than the ProSub 800 which gives it a small disadvantage 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 JBL Stage A120P weighs 18.68kg / 41.1lbs and the Definitive ProSub 800 weighs 11.82kg / 26lbs. This makes the A120P 58% heavier than the ProSub 800.
Here is a comparison of how A120P and ProSub 800's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of JBL Stage A120P?
Here are the items that are included inside the box of A120P:
- Powered subwoofer
- Grille
- 6-feet AC power cord
- 4 Spike feet
- Owners Manual
- Warranty Card
- Important Safety Instructions
What's in the Box of Definitive ProSub 800?
Here are the items that come with the ProSub 800:
- 8-inch Powered subwoofer
- Detachable grille (installed)
- 7-feet AC power cord
- Owners Manual
- Online Product Registration card
 Woofer Size |
12 inches
vs
8 inches
|
Larger woofer |
 Price per pair* |
300USD
vs
399USD
|
costs less (*prices may change depending on the seller, location and time) |
| Low Frequency Response |
20 Hz
vs
32 Hz
|
Generates deeper bass |
 Height |
328mm
vs
415mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1108cm2
vs
1866cm2
|
Takes less floor space |
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.
JBL Stage A120P needs about 68% more floor area. JBL Stage A120P stands 52mm further into the room. JBL Stage A120P is 87mm taller.
| General |
JBL Stage A120P |
Definitive Technology ProSub 800 |
| Brand |
JBL |
Definitive Technology |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
250 watts |
300 watts |
| Frequency Response |
32-150 Hz |
20-150 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
250-watt RMS |
300-watt RMS |
| Watts Peak (Max) |
500-watt RMS |
n/a |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
12" |
8" |
| Woofer Composition |
Polycellulose |
Polymer |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
40-150 Hz and 80 Hz |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
415.0mm (16.3") |
328.0mm (12.9") |
| Width |
393.0mm (15.5") |
262.0mm (10.3") |
| Depth |
475.0mm (18.7") |
423.0mm (16.7") |
| Weight |
18.68kg (41.1lbs) |
11.82kg (26lbs) |
| Enclosure |
Bass reflex |
Passive Radiator |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
1 Year |
3 Years |
| Labor Warranty |
1 Year |
3 Years |
A ported subwoofer against a passive radiator 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 | B | Definitive ProSub 800 goes deeper - 20Hz against 32Hz. Under 20Hz is felt more than heard - the bottom of a pipe organ and the bottom of a film mix. |
| Amplifier power | evenly matched | Much the same amplifier (250W vs 300W RMS) - under 1dB apart. |
| Driver area | A | JBL Stage A120P moves more air: 12" against 8" is 2.25x the cone area, not the 1.5x the diameters suggest. More area means the same output with less excursion, and less distortion with it. |
| Enclosure | depends | JBL Stage A120P is ported - a ported box gives more output low down for its size, at the cost of a steeper roll-off below tuning; Definitive ProSub 800 is passive radiator - a passive radiator behaves like a port without the pipe noise, and suits a slim cabinet. Neither is better in the abstract; ported tends to suit films and sealed tends to suit music, and both generalisations have exceptions. |
| Speaker-level inputs | B | Definitive ProSub 800 takes a speaker-level connection as well as line level. That is what lets it work with an integrated amplifier or a vintage receiver that has no subwoofer output at all. |
| Phase control | A | JBL Stage A120P has a phase control. Without one, the only way to fix a cancellation at the crossover is to move the box. |
| Cabinet size | depends | Definitive ProSub 800 is about 53% 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 | B | Definitive ProSub 800 carries 3 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 | JBL Stage A120P costs less - $300 against $399, about 25% less. |
A JBL Stage A120P B Definitive ProSub 800
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?
The usual trade-off: Definitive ProSub 800 measures better, JBL Stage A120P costs about 25% less. In a normal room, placement will make a bigger difference than the gap between these two. Check your amplifier first: if it has no subwoofer or preamp output, Definitive ProSub 800 is the only one of these two you can connect at all. If placement is the constraint - a corner, behind a sofa, under a desk - Definitive ProSub 800 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.