JBL PRX815 vs QSC K12

The sound of the JBL PRX815 can be thoroughly edited via Wi-Fi on the free PRX connect mobile app, giving the user wireless control over volume levels, gain and 8 parametric EQ’s, letting the user boost a wide range of frequencies.

The app allows configuring speakers to have a delay of up to 50ms. This helps when managing different acoustic environments, or for achieving distributed delay in the case of a bigger speaker setup, so the back of the room has the same listening experience as the front.

The app also packs a "preset" feature, allowing users to save setups for specific environments or venues if the need to play in the same place arises.

On top of the asymmetrical build (for possible stage monitor use), the speaker also features a handle on the side and 12 M10 suspension points, so it is possible to suspend the speakers from the ceiling or a stage proscenium.

Coming in at 47.5 lbs (21.6 kg), the speaker doesn’t quite excel in lightness, but it’s still on the lighter side when compared to other 15” speakers, and it’s also easier to grip because of the finish.

The speaker has a coverage pattern of 90 degrees x 50 degrees nominal, which is a common and widely used pattern in DJ speakers, but the PRX815 does particularly well with providing good frequencies off-axis thanks to the built-in wave guide, delivering consistent sound for the crowd. This also makes placing the speakers an easier job to do.

Being a 1500-watt class D amplifier, it packs more of a punch than the visual might suggest. The PRX815 covers almost the whole frequency range of human hearing and provides a flat frequency response in this spectrum. According to the frequency response graph, the peaks don’t vary past -4 dB in the hearing spectrum, meaning the speaker has clear, accurate sound even at high volumes.

In terms of sound quality, this speaker truly shines because of the strong bass – it packs two heat-dissipating voice coils for greater low-frequency extension and higher low-frequency output.

The speaker has a monitor mode, which means that it can be used as a stage monitor instead of a front of house (FOH) speaker. This is done by taking some of the bass out of the equation.

Though it is not recommended to push this limit, it can reach a peak of 137 dB (in comparison, this is approximately as loud as a jet engine at take-off), so playing for larger crowds (200-300 people) won’t be an issue at all.

The PRX815 also has a built-in variable-speed fan that activates automatically at high volumes, letting you push the speaker a lot closer to its limits without fear of damaging it, because it activates only when the speaker is getting overheated, not only preserving it, but also letting music be played for a longer while. The signal light on the back of the speaker is a good indicator whether peak output has been reached.

The speaker is made from a combination of 25 mm and 18 mm plywood and a dent-resistant 16-gauge steel grille. The wood is covered with fiberglass reinforced plastic, which is used in manufacturing body kits for cars, making the JBL PRX815 very rugged and tough – it can easily sustain scratches and hits without visible damage.

The QSC K12 is very powerful for a 12” speaker. It's very loud, peaking at 131 dB, which is equivalent to a marching band of 200 members. Basically, using this speaker won’t be a problem for both smaller and bigger crowds, it can easily handle 200+ people.

The speaker features extensive DSP (Digital Signal Processing). What this means – the speakers offer matched low-frequency and high-frequency clarity all around the spectrum so something like a guitar won't get overpowered by a kick-drum in the final product you hear being played from the speaker.

What’s more, the speaker’s coverage pattern is 75 degrees conical and it features DMT (Directivity Matched Transition) for a matched listening experience and an equal performance in the whole area.

The speaker packs a rugged ABS enclosure and a 16-gauge steel grille, so it can sustain regular and long-term gigging.

If the speaker happens to be pushed closer to its limits, not only is it indicated by a signal light, but a cooling fan turns on, which, luckily, isn’t hearable.

One of the more impressive features the speaker packs is the onboard mixer with switches for equalizing.

The HF (high-frequency) setting can be set from "_Flat_" (normal mode) to "_Vocal boost_". This enhances the mid-frequency area where the human voice is located for additional clarity, making this a good enhancement for people using the QSC K12’s for karaoke or playing vocal-heavy tracks.

The LF (low-frequency) switch can be toggled from "_Norm_" (regular mode) to:

1. "_Ext sub_" for the removal of low frequencies from the speaker in the case of an external subwoofer being present,
2. "_Deep_", which extends the bass frequency response without distorting the signal or adjacent frequencies, smoothly and effectively enhancing the bass output from the speaker.

This is ideal for people wanting to play bass-heavy music such as hip-hop or electronic music without fear of having to spend more money on a subwoofer.

While the QSC K12 is quite heavy (41 lb / 18.6 kgs), it’s still reasonably portable due to the two handles.

A feature that is unique to this speaker is that it has a dual angle pole socket that offers you the possibility of tilting the speaker 7.5 degrees downwards. This is very useful for achieving maximum coverage from a high-positioned speaker.

The M10 suspension points also offer the possibility of suspending the speaker from the ceiling, though this requires a K Series M10 kit, which is sold separately.

Since the speaker is asymmetrical, it can also be used as a stage monitor.