Cerwin-Vega P1500X & P1800SX

Offering built-in mixing facilities and DSP functionality, there's more to these self-powered speakers than meets the eye.

The name of Cerwin-Vega has been around a long time in the pro-audio world, and the company's latest portable speakers are the new P-series self-powered cabinets. The range currently consists of just two speaker models: the P1500X full-range speaker and the P1800SX sub. These are, of course, designed and marketed as a complete system — although either can be teamed up with other suitable equipment, for example as part of an upgrade to an existing installation. I had the opportunity to try out a pair of each, spent a couple of weeks getting to know them in the workshop, and managed to get them out on a couple of band jobs, too.

From The Top

The P1500X is a two-way, active design with a 15-inch woofer, a one-inch-exit HF driver mounted on an integral waveguide, and a dual power-amplifier section (ie. it uses an 'active' crossover and two separate amp circuits). The moulded-polymer cabinet is shaped to allow it to be used on main PA duties, or as a floor wedge monitor at a 45-degree angle. It is equipped with pleasingly chunky rubber feet on the bottom (two 'doorstop' types to the front and a solid bar toward the rear), and two decent-sized bar grip handles on the side and top surfaces. The top handle was particularly useful for getting it out of the shipping box!

The whole enclosure is quite compact considering its 15-inch-woofer format, and it weighs only 24kg, which is definitely on the lighter side for a unit of this size and power. My first impressions were of a solidly built unit with a good standard of finish.

Both the P1500X and the P1800SX are equipped with pole-mount sockets of good quality. They are also both fitted with strong, black, steel grilles, shaped to fit the contours at the front of the cabinet. These look more than capable of providing a good degree of protection to the driver units within.

The pole-mount socket on the P1500X has a dual-angle arrangement, whereby rotating the socket results in the cabinet sitting at a downward angle of 7.5 degrees — which should be useful for smaller venues, or any situation where ceiling reflections might be a problem.

As with most integrated powered speakers, no specs other than dimensions are given for the drivers themselves, but from a company with Cerwin-Vega's long loudspeaker pedigree, I'd imagine that they are well matched to the power amps and perfectly capable of handling all the available power. The Class-D amp output is given as 540W continuous power, or 1500W 'dynamic'.

Mixing It Up

The P1500X features a three-input mixer section on the rear panel, which can accommodate mic and line inputs. Also on this panel are switches for engaging the various EQ and filter settings.

Worthy of further investigation is the P1500X's input section, which features a three-channel mixer and various other features. The control panel provides two identical balanced input channels, each with a combi-type XLR/TRS connector and a link output jack, as well as an LED clip indicator. These inputs can be switched, independently, for line- or microphone- level operation. A third input is available for connecting unbalanced 'consumer' equipment, and this has a pair of RCA sockets to which a stereo source can be fed, but which is summed to mono in the preamp stage.

All three input channels feature a rotary level control, and the mixer section has a balanced XLR master output which feeds the mixed inputs to another speaker, or wherever else you want it to go. The mix output is not controlled by the P1500X's master level control, which is good in that it allows individual daisy-chained speakers to be balanced separately even when linked to the same mixed signal. It's worth noting, though, that the 'thru' outputs are not hard-wired — they will only give an output when the P1500X is switched on.

The 'master' section contains all the important signal-processing and speaker-protection features, and these are implemented digitally, thanks to onboard DSP. Three switches allow access to EQ options, although the DSP also has functions that you can't control, such as the subsonic filtering, crossover and limiter.

EQ Options

Let's take a look at the EQ settings. The 'Vega Bass' function is like the bass end of a traditional loudness control: it boosts the level of the lowest frequencies by a varying amount, depending on the overall output level, and is very effective at rounding out the sound when you're playing the P1500X at lower levels (for background music, say). I liked the dynamic action of this feature, and I imagine people who use the P1500Xs without subs will appreciate it a lot.

The 'enhance' switch introduces a broad dip in the mid-range, giving the impression of clearer high- and low-frequency content. This function is worth spending some time with, especially in challenging acoustic spaces: I found that the best way to decide whether to switch it in was to move to a reasonable distance from the speaker (where your audience would be) and decide whether it improves the overall sound in the room, rather than listening from right in front of the speaker.

Finally, the high-pass filter switch does exactly that: it cuts below 80Hz, which is essential for floor-monitor use, and also when the P1500X is operating in conjunction with a subwoofer but is being fed a full-range input. The master section provides warning LEDs for power on/off, limiter operation and auto-protect, which will show if the unit has shut down automatically in response to a potentially damaging condition.

The P1500X boasts a couple of other interesting features. There's a handy switch that enables a front-mounted limiter LED, so that an out-front operator can see when things are being pushed too far — a great idea, this, and one which I wish all powered speakers used! There's also a three-terminal connector block, which enables a wired remote volume control to be connected. This is handy for install use and could also remotely control distributed PA coverage over relatively long distances.

The Low-down

The subwoofer has two inputs for left and right channels (internally summed to mono), as well as thru outputs and a mono link out for connecting to another sub.

The P1800SX subwoofer is based around a single 18-inch woofer. The cabinet has a black finish to match that of the P1500X, but it is, as you'd expect, of 18mm wooden construction, rather than being moulded plastic. It's supplied with a set of good castor wheels that bolt straight on to the captive fittings. The P1800SX's control panel is similar in layout and design to the P1500X, but has only two inputs. These allow a stereo signal to be summed to mono, and each input has a link output that would normally be used for feeding a full-range speaker. Like the P1500X, the 1800SX has a mix output for linking to another sub, and features the same indicator LEDs.

Unusually, the P1800SX has some EQ options of its own. The Vega Bass boost is present, providing some real bottom-end deepness, and there is a combined filter switch, which introduces a high-pass filter before the 'thru' outputs, and a low-pass filter to feed the sub's amp section. The final control is a switch that inverts the sub's polarity. The P1800SX's amp is a bridged design and is rated at 725W continuous power (2000W 'dynamic').

Power Up

I set up a single P1500X and P1800SX in the workshop to get an initial impression of the sound and performance, before taking the whole system out on a couple of real jobs. The P1500X has only a single side handle, but I was able to mount the speaker on its pole above the sub quite easily by myself; the top handle is effectively redundant in this situation, as it's too high to reach if you're standing on the floor. The P-series units are quiet at switch-on, with an initial mute state preventing unwanted pops or thumps. The automatic fans give a reassuring little kick on power-up too, although at normal room temperatures they will stay off until needed.

I started with some tracks playing at low level, and noticed that the P1500X has a clear and 'forward' upper mid-range with no unpleasantness or harshness around the woofer/horn crossover region. The system sounded good with all my test tracks, and I tried switching in the various EQ options, which seemed to support the descriptions in the manual. At higher levels, and in the confines of the workshop, I couldn't decide whether I preferred the mid-cut switched in on the P1500X or just a gentle dip on the mixer, but whether the filter was in or out, the clarity remained even when I began to push the speakers quite hard.

Sense & Sensitivity

One thing I did notice early on was that I wasn't getting as much output from the P-series units as I had expected with the usual settings on my test setup, and I had to turn up the speaker level controls quite high to compensate. This was most noticeable when I started comparing the P-series speakers with other similar products: feeding the P1500X as well as three other powered speakers (all similar full-range boxes, and without subs) with the same signal level gave me noticeably less output from the P1500X than the other brands. Just to check, I fed each speaker in turn with the same pink-noise source and, at moderate volume with the speaker controls all fully clockwise and all EQs disengaged, I did a quick SPL measurement and found that the P1500X was giving between 4dB and 6dB less output than the others. This isn't actually a problem, however, given that the P1500X can be driven to its full specified output, provided you have a desk capable of delivering the full required professional standard +4dBu into the line-level inputs. When I ran the P1500X up to full output, it went into limiting at exactly the same point as my desk meters went into the red, which is perfect gain structure right out of the box.

I contacted Gibson Pro Audio (Cerwin-Vega's parent company) about this, and asked if there was any reason for the apparent lower sensitivity. They told me that, as the P-series is designed to be run at 'pro' levels, they have resisted the temptation to hype the input sensitivity just to give the impression that it sounds loud compared to the competition in a demo — perhaps a brave move on their part! They also pointed out that the balanced input channels actually sum, so you could feed the speakers the same balanced signal twice, to increase the overall sensitivity by 6dB. Of course, the third input is set to operate at the consumer standard of -10dBV, so in reality I reckon they have all normal uses covered.

The only down side I came across was when feeding the P1500X via the filtered 'thru' output on the P1800SX. With the sub's combined HPF (for the Thru output) and LPF (for the sub signal) switched on, the sub introduced a bit of low-frequency idling noise in the P1500X. This would be practically unnoticeable and therefore irrelevant when the system was playing at anything more than a very low level, but might well be an issue for some types of AV or small-space presentation work. There is a workaround for this, however, as all you have to do is feed the source input signal to the P1500X first, then link out to the sub (in other words, the opposite way to the hook-up suggested in the manual), and the problem goes away.

Hit The Road

I got the P-series speakers out to a couple of band rehearsals, where I was able to put them through their paces in a more realistic environment, and although I didn't end up driving them at insane levels I was more than happy with what I'd describe as a big, clean output. At the second session, I was in a larger space, and with more people in the room I found that the 'flat' EQ settings worked best for me, and the crisp mid-range from the P1500Xs really came into its own. On piano and acoustic guitar, I reduced the mid-frequencies on the desk channels, but left everything more or less flat on both male and female vocals, with good results.

One noticeable property of the P1500Xs is that the sound balance doesn't seem to change much between 'pretty loud', 'loud' and 'very loud', and once I worked out a good mix I was basically able to leave everything alone for the rest of the session. In purely practical terms, the only thing that caused me a problem was the design of the P1800SX handles, which are strong and good-quality fittings, but the recess isn't really big enough for your hand to fit in, and I found this made carrying it quite uncomfortable. Performance-wise, though, the P-series speakers have plenty of power available, and the high-frequency dispersion (nominally 90 degrees horizontal by 65 degrees vertical) is good for most small to medium-sized venues.

I had really wanted to try these speakers in an outdoor venue, but my one open-air gig was cancelled because of snow, so unfortunately I never got to really push these speakers except in the workshop — although I did manage to frighten the guys in the next-door unit by playing a recording of fighter jets and tanks firing! My neighbours will testify that these subs have much bottom end...

After working with the P-series for a while, I'm left with an impression of toughness. They are built and perform solidly, and are capable of banging out loud and clear audio all day and night. They're pretty versatile, too, with their various EQ options, remote volume-control capability and three-channel mixer on the P1500X, all built into a modest and manageable size. In short, the P-series is well worth looking at if you're in the market for a powered PA system.