Mackie SA1530z

I bought a second-hand pair of Mackie SR1530 powered speakers about three years ago, and they've remained one of my favourite choices for a variety of live sound work. The active three-way design is particularly clear and natural-sounding, and I like to use them for acoustic instruments and small-scale theatre work. I even bought a second pair to provide more coverage for modest outdoor events. But for slightly bigger work I always wished they had more power, so when the SA range was extended to include an up-rated version — the SA1530z — out came the credit card and in came a pair of new speakers.

The basic design hasn't changed, in that they are full-range, three-way enclosures with built-in power amplifiers (there are actually three separate amps that drive the three drivers). And all the necessary active electronics are incorporated within the power amp module, so all you have to do is connect a full-range signal and away you go. The drivers are now lightweight neodymium versions, the LF power amp has a much bigger output and the electronics have been tweaked to obtain maximum performance from the revised setup. The only obvious external difference is the front grille, which is silver on the 'z' models, as opposed to the original black on the (still available) SR series.

The SA1530z has three separate power amp modules, each powering its own driver covering a specific part of the audio spectrum. The HF section consists of a Class-A/B 100W amp, paired with a neodymium compression driver, having a one-inch exit diameter and mounted on a moulded horn, which gives a nominal coverage pattern of 90 degrees horizontal by 40 degrees vertical. The dedicated mid-range driver has a six-inch diameter reinforced cellulose cone and again makes use of neodymium for its magnet material; mid-range power is provided by another dedicated 100W Class-A/B amplifier. Low frequencies are powered by a Class-G power amp delivering a huge 1100W, and driving a 15-inch woofer with a four-inch voice coil and a (more traditional) ferrite magnet assembly. Crossover points are set at 700Hz and 3kHz; the use of a dedicated mid-range driver allows the upper crossover point to be set pretty high, which means that the compression driver can work with great efficiency and reliability. A big feature of the Mackie three-way design is the alignment of the mid and high drivers, in that the HF section is angled slightly to fire down into the mid-range path to create a well-focused wavefront at MF and above. The mid driver handles the whole of the normal vocal spectrum and is not therefore affected by the use of a crossover circuit or multiple driver types. The vocal clarity from these speakers is very impressive and they give excellent results with acoustic instruments, particularly acoustic guitar, which comes across beautifully. The 15-inch woofer occupies the lower part of the cabinet, which has two large, round ports at the very bottom — the generous amount of power available dictates that this driver must be capable of taking a generous amount of stick for long periods of time, and the four-inch voice coil should help to disperse heat and minimise the effects of power compression. When I rig these speakers to run full-range, I have always been more than happy with the amount of low end, which stays well controlled even when driven very hard and packs a tremendous wallop.

Because the 1530z is a 'Plug and Play' product, it needs some sophisticated internal electronics to (a) get the best audio performance and power from it, and (b) ensure it doesn't get stupidly overdriven or become too hot. The amplifier module provides dynamic bass protection, RMS power limiting, and thermal protection of both power supply and amplifier stages. The internal limiting circuit will prevent clipping at the amplifier outputs and will also prevent overdriving the speakers — operation of the limiter is indicated by an LED on the rear panel. Thermal protection circuitry monitors the operating temperature of the amplifiers and automatically mutes the audio signal if the temperature rises above a safe level, then resumes normal operation when the amps have cooled down. The performance of the whole system is optimised by onboard processing, ensuring that the amps and drivers function together and are perfectly matched, requiring no external processing.

On the physical side of things, the SA1530z cabinets are about the same weight (50kg) as my older SR1530 versions. I'm guessing this is because the reduced weight of the HF and MF magnets is balanced by the addition of a much more powerful (ferrite-equipped, four-inch voice coil) LF unit to handle the increased power. I'm glad that the external dimensions and basic appearance haven't changed from the SR version because it's a nice thing to look at. And also, at a pinch, the old and new cabs could be used together (for example, a pair of the lower-powered SR cabs could be used splayed out for side coverage at lower power) and still look like they're part of the same system. The SA1530z is made of 18mm ply, with moulded resin top and bottom panels that are well finished and have no sharp or vulnerable corners to worry about. The cabinet is about 44 inches high and 19 inches wide at the front, narrowing at a 15-degree angle to 14 inches at the rear, and the height in particular is a mixture of useful and problematical — if you use them on their own as full-range cabs without subs, then they really need to be stood on top of something a couple of feet high or so to get the horns above head height (they can't under any circumstances be pole- or stand-mounted), which would mean that bass performance would be compromised. Personally, I always use these speakers standing on a pair (or even better, two pairs) of subs because this puts the horns at a useful height and lets the true subs work the low end as they are designed to do, letting the full-range cabs put all their available power into dealing with the signals above 100Hz or thereabouts.

Lifting the SA1530s is quite easy, provided there are two of you — I can just about hump them around for a few feet at a time, but I couldn't carry one any distance. Fortunately, they are a perfect size and shape to ride on a sack barrow, and I have a compact folding one that travels with the Mackies. The side handles are substantial metal castings, the grip bars are comfortable and there's a good deep recess to get your knuckles into. When standing these speakers side by side in the van, I slide a piece of cardboard between them, as the middle of the metal handles protrude slightly and can chafe against each other — an even better idea would be to use proper covers! I particularly like the oversize rubber feet on these cabs, although they can come unscrewed if the cabs are pivoted on them when 'penguin-walking' them into position.

The entire front surface of the cabinet is protected by a strong, curved, steel grille, which has the Mackie trademark blue LED near the bottom — this can't be switched off, so I cover mine with black tape for mobile theatre productions. Build quality appears to be very good, and I know that my speakers have been bounced around in the van and used at all kinds of indoor and outdoor events without collecting any noticeable battle scars.

The control panel is inset in the rear panel, and has an IEC mains power connector and on/off switch at the bottom, and XLR input, link output, level control and indicator LEDs at the top. In between (and occupying most of the panel space) is a huge, vertically-finned heat sink for the power amps, with the fins sensibly profiled so as not to protrude beyond the back surface of the cabinet itself. There's no fan and heat dissipation relies on convection cooling, so it's very important not to obstruct the heat sink or impede natural ventilation in this area, although I have run my speakers flat out for a couple of hours at a time without them getting hot enough to cause any concern. I like the addition of a level control on the back panel — my older SR1530s didn't have this luxury so they were, in effect, turned fully up as soon as they were switched on. The SA1530z has more in the way of LED indicators too — as well as 'power on' and 'limit' there's one labelled 'Thermal' that warns when the unit has gone into self-protect mode because of over-temperature. And there's a useful 'signal' LED, which shows that a signal is present at the input connector — very handy when trying to trace problems with cables etc.

Using these powered speakers is about as easy as it gets; assuming that everything is connected up properly (ie. you stick an XLR in the back) and the cabinet is sitting at a reasonable height relative to the listening position, all that remains is to turn up the level and enjoy the music. As I said, over the years I've used my old SR1530s for all manner of events, and I've always been very happy with their performance, but upgrading to the SA1530z models has brought significant new depth and power. They sound really well-balanced on their own and with my SWA1801 subs, but the additional power and projection has meant that they can now be used for an even wider range of applications. And because of the increased output, I get away with only a single SA1530z each side of the performance area, so frequency cancellations aren't an issue.

Just out of personal interest (and having nothing better to do on a miserable cold morning), I took one new SA1530z outdoors and did a rough, highly unscientific comparison with the old SR version. The published specification claims a significant increase in maximum sound pressure level (135dB at 1m), because not only does this speaker have a much more powerful LF amplifier and 15-inch woofer, but it also has newer, more efficient HF and MF components, and the whole thing has been retuned by Mackie's boffins over at EAW. First, I ran subjective A/B listening tests with a bit of unexciting, but clean Larry Carlton, and got a couple of colleagues to wander around with me just 'having a listen'. We agreed that the SA1530z had noticeably more power for the same input level compared with the SR1530, mainly due to the massive bottom end, which really kicked out to a good 20m or so. I didn't bother with a sub, but just used flat EQ settings and stood the cabs on some grass, aiming them out into the open field so as to avoid too much reflected sound. The top end on both was clean and clear, and I was reminded of why I've always liked the old SRs so much. The SAz model, though, definitely sounded crisper all round, and the sound balance sounded even and pretty constant no matter how far away we stood, at least for the first 20m or so. Coverage off to the sides was very good and I wouldn't argue with the published 90-degree dispersion figure. The additional low output really hits you and, at least in this context, there was no suggestion that the LF balance has been overcooked just to make the numbers look good — it just works.

To see what the difference in output might look like on a display, I rigged up a spare dbx DriveRack PA as a pink noise source, fed it straight to the speaker under test, then placed a measuring microphone approximately a metre in front (measured from the front edge of the blanked-off 'pole hole' on the top panel, which looked roughly where the HF driver throat would be) and at a height in between the HF and MF horn sections. The mic was then fed back via a small Soundcraft mixer to a Tektronix 2012 oscilloscope set up to operate as a simple spectrum analyser, and the outputs from the two speakers compared. The screenshots illustrate the difference that we heard. I also did a quick SPL measurement — from the microphone position — by increasing the pink noise input level to the point where the speakers' internal limiters kicked in. With the sound level meter set on fast response and peak hold, I got some consistent results over three or four attempts, and was able to measure a difference of 8.8dB (119.8dB for the SR1530, 128.6dB for the SA1530z). These figures seemed to bear out the difference we had listened to, and although I wasn't using a 1kHz tone, this simple test does illustrate the big increase in real, useable output level that the SA1530z produces over the SR model. It's interesting to note that the official figures (maximum long-term SPL at 1m) for these two speakers are in fact 123dB and 132dB respectively, which puts them 9dB apart — pretty close to my 8.8!

I've been very pleased with my SA1530z speakers, and looking back on how much use I've already had from them, I reckon they definitely fall into the category of money well spent. Having taken the time to really listen to (and measure) the difference, I would recommend this upgrade to any SR1530 users who are looking for a substantial power increase without losing the sweetness and clarity of the original design. There are, of course, other three-way speakers in the SAz range, including 2 x 12-inch and 2 x 15-inch LF driver variants, and these may be well worth a look if you want to thump out even more power. If you need something physically smaller, there's a two-way 500W model called the SA1521z, which can, technically, be pole- or stand-mounted. The Mackie website contains all the relevant technical information, and part of the user forum deals specifically with their live sound products and is a good place for advice once you've figured out which members really know their stuff. For the kind of live sound work that generally comes my way, the SA1530z remains my choice, as I think it's a great blend of quality and power at an affordable price. Given the newer generation drivers, increase in amplifier power and the expert retuning that has been done to an existing successful design, it's not surprising that the SA1530z sounds so good or projects so evenly. For club, acoustic and small venues, the vocal and instrumental clarity is excellent and there's more than enough bottom end. For bigger gigs, team these up with four subs and you've got a really nice versatile rig. 0

Mackie SA1530z

Active three-way PA system