Turbosound Milan M15 & M18
Active PA Speakers & SubwooferReviews : PA system
The M15 active speaker promises Turbosound’s trademark warm sound, while the M18 subwoofer is designed to add some extra low-end level.
Turbosound is a well-respected name in the professional live sound arena, so anything that’s aimed at the portable sound market and bears their famous logo is definitely of interest. The Milan range of self-powered speakers is just that, and I’ve had an opportunity to become acquainted with it.
I had already enjoyed using the smallest family member, the Mi0 (see SOS January 2012), which hugely impressed me with its crisp, fresh styling and larger-than-life sound quality, so I was very keen to get to grips with the larger M15 and M18 combination. Since Turbosound sent me a pair of M15 speakers and a single M18 subwoofer, I decided to spend some time working with the M15s on their own, before using all three of the components together.
Keeping Up Appearances
The M15 active loudspeaker has the same external styling as the smaller Mi0, in that it is made from the same shade of moulded polypropylene (dark blue or dark grey, depending on your eyesight), with silver aluminium side panels and a matte-silver steel grill covering the whole of the front. It’s a real looker, there can be no doubt, and I can’t imagine anyone disliking the classy appearance. The style is fresh and modern but lacks any ‘bling’ factor, so the system should fit nicely into almost any context — as long as it doesn’t have to disappear completely against a black background, that is.
The M15 uses a 15-inch low-frequency (LF) driver, but is somewhat larger than most 15-inch, two-way powered cabs. It’s not all that heavy, though, at 22kg, which means that lifting, carrying and even mounting it on a pole or a stand can be done by one relatively fit person. The side handles (formed by a recess behind the large aluminium side-strip) feel secure and accommodate a fairly large hand, though the edges where the handle meets the plastic cabinet sides feel slightly uncomfortable and could do with a bit of rounding off.
There’s a good-sized handle built into the top of the cabinet, too, which is particularly useful when simply moving the M15 about on the floor or in the back of a van, as it means it’s not necessary to bend down to pick it up. To be really picky, the front edge of this handle would benefit from being fractionally further back, as I think the cabinet would then be perfectly balanced and would lift directly upwards more easily.
The shape of the M15 is designed so that the speaker can be used as a floor wedge, and it’s nice that it’s been made symmetrical, so you can have the high-frequency (HF) end to the left or right. This is a useful feature when space is very tight: for example, in an orchestra pit, where close individual monitoring may be required, and the tweeter-horn mouth might easily be obstructed. It has to be said that the M15 is quite large for use as a floor monitor, and I’d tend to use them as such only for larger stages.
Something I had a doubt about was the shiny silver finish on the side panels, which would prevent me from using them as downstage ‘footlight’ wedges in a theatre production, as they would be visually distracting. It’s worth mentioning the cabinet ‘feet’ at this point: Turbosound have designed a neat, slim rubber strip which follows the cabinet shape all the way round the back and both sides, and provides excellent stability, protection and grip. The rubber strip incorporates rubber locating pegs which fix into holes in the cabinet, and the strip is glued into place.
It’s quite secure, and I tried dragging the M15s across carpeted and wooden floor several times without the strips becoming detached or distorted. A neat and highly practical touch is the inclusion of dual pole-mount sockets, which allow mounting straight or at a downward angle. The latter orientation directs the sound into the audience area and can significantly improve coverage and clarity in difficult venues.
The M18 subwoofer is quite different in appearance from the M15, in that it is of more traditional plywood construction, and has a textured paint finish that matches well with the M15. My initial reaction on unpacking the M18 was that it looked larger than I had expected, but I think this is because of its slightly over-square proportions. It’s slightly wider than tall, and therefore looks squat and very businesslike. It’s equipped with four good, strong swivel wheels, and it does fit through a smaller gap than you might think: the shortest dimension is just under 20 inches, which will see it safely through a half-open double door.
Tipping the M18 onto or off its wheels is an easy one-person job, and the wheels are large enough and positioned sensibly, so the edge of the cabinet doesn’t scrape on the ground when doing this. I was able to transport the M18 on my own because I have a ramp for getting such things in and out of my van, but I’d definitely have required assistance to pick it up or carry it — not because it’s too heavy, which at 45kg it isn’t — but because it’s too wide. Also, the cut-out handles are not designed for this task, being located right at the rear edge of the side panels.
A single, metal, 35mm pole socket is set into the top of the cabinet, and there are rubber feet fixed firmly to the bottom. The M18 is a very sturdy beast, and quite capable of being pressed into service as a trolley for moving other equipment, though obviously it’s not recommended.
Both the M15 and M18 speakers use specially designed modern drivers with lightweight, efficient, neodymium magnet structures. They also employ class-D power amplifiers, which means that the amp power efficiency is high and weight is low: the whole amplifier module in the M15 weighs less than 2kg. The full-range M15 has two identical inputs that can be switched to line or microphone sensitivity settings, which are summed and fed via a two-band equaliser to the power amp, as well as a link output that passes the complete mix onwards.
This mixer output is a useful feature, especially if the M15 is being used as a portable stand-alone PA system, as it offers the option of a simple link across to the other speaker for a mono system, as is often used in worship and assembly spaces. The ability to plug a dynamic or self-powered microphone straight into the M15 is great for solo or duet performers, but you need to be careful not to accidentally switch the input from ‘line’ to ‘mic’ while the system is operating at performance levels, as the resulting level change will be dramatic.
The M15 is designed to be used as a full-range main PA speaker, but also as part of a larger system with the M18, or as a monitor. There’s a 100Hz high-pass filter labelled ‘bass mode’, which will almost always be used in the latter two cases.
It’s easy to overlook the M18 subwoofer when talking about the features and pretty appearance of the M15, but running good full-range cabs with a well-matched sub allows you to release the full potential of the main speakers, as they are not trying to cover the entire frequency range. The subwoofer itself is a single, 18-inch, band-pass design with a built-in, 1kW, class-D power amplifier.
Like the M15, the M18 has two input channels (line level only this time, of course) but each input has its own filtered output setting of 80Hz or 125Hz and a full-range link output for connecting to another sub. The inputs are summed, and fed through a low-pass filter to the power amp, where a single level control is available. The subwoofer is capable of producing a maximum SPL of 131dB, and is continuously rated at 125dB.
Looking at the audio performance figures for these speakers, it’s interesting to see that the low-frequency -3dB point of the full-range M15 is, at 36Hz, below that of the M18 sub, which is 44Hz at the same point on the curve. This doesn’t in any way mean that it will out-perform the sub, but it is a good indication of the M15’s flexibility as a go-anywhere sound solution.
The M15 on its own is more than worthy of the description ‘full range’, and has the best low-end performance I’ve heard from a two-way powered design. The output falls off to only -3dB at a very impressive 36Hz and believe me, it really does push out some serious low frequencies. Upper-end output falls off by 3dB above 17kHz, and the HF dispersion is 90 x 60 degrees, horizontally favoured. In practice, I thought the dispersion sounded usable at a wider angle than this, and in a ‘typical’ reflective space (a bar) the HF programme was still clear and strong when stood well outside the specified field of fire.
Check, Protect & Serve
The M18 sums the stereo input signal to mono, then applies a low-pass filter at one of two fixed frequencies.
The M18 sums the stereo input signal to mono, then applies a low-pass filter at one of two fixed frequencies.
When I tried a single M15 as an open-air announcer rig, I found the high-pass filter very handy for reducing mic handling and other extraneous noises, including wind rumble. The M15 has a single power amp, and uses a passive crossover to feed the LF and HF drivers, which are physically aligned within the cabinet and don’t require additional delay processing. The amp has a rated output capability of 450W (programme) but what’s more important is the continuous SPL figure of 125dB, with a maximum output reaching an impressive 131dB.
Another essential feature and strong selling point of self-powered speakers is the built-in peak protection, which allows the user to just ‘plug and play’. The M15 and M18 are so equipped, using DSP circuits that apply fast limiting to the signal before it reaches the power amp. I like to set the system gain structure when I rig up a portable PA, and I like to know what my mixer output level is relative to the limit point of the powered speakers, because warning LEDs are usually on the back where they can’t be seen from the mix position.
I ran pink noise through the Milan rig and set the M15 and M18 level controls to the point of ‘just limiting’, wishing, as usual, that designers of powered speakers would one day provide a mute switch so that I could test this without frightening the neighbourhood! I then ran programme material (starting, as always, with Zena James’ lovely ‘Captivated’) and immediately reduced the sub level, not because it was limiting but because it was just too loud. In my opinion, just a single M18 will keep up with a pair of M15s running at a sensible level, providing the right amount of solid and very satisfying bottom end.
The Milan system sounded powerful and it sounded smooth. I first listened to the M15s in my workshop, and could detect no harshness or unnatural high-frequency lift. Whatever programme material I put through them sounded warm and full of character, by which I mean that these speakers sounded well-behaved and ‘flat’, but definitely not bland. There was a liveliness to the sound, and I didn’t immediately think that the top end or the low end or the middle range particularly stood out, rather that the sound was somehow ‘complete’ across all ranges.
The Milans are simple to connect and adjust, and they’re nice and quiet in use. There’s a very slight click as the speakers are powered up and down, but no annoying or driver-damaging pops even if you cycle the power quickly.
I wish I had time to take the Milan speakers out on a few more jobs, as I’m getting to like them a lot. I did test them outdoors (with recorded music and a single live performer), with very good results. Judging by their indoor performance, where I never got anywhere near to using their full output, I’d say they’d be more than capable of doing justice to a full band, and I certainly wouldn’t hesitate to run them on the limit for a couple of hours or so.
In combination, the full system is easily portable, very powerful, and will deliver the goods in a wide variety of live sound applications. Even used without the M18 sub, the M15 is a very good full-range powered speaker, with great looks, sound quality and level in abundance. 0
Alternatives to the M15 include the HK Audio PRO15XA Premium PR:O, Yamaha DSR115 and JBL’s PRX615M 15-inch active speakers, while the M18 competes with JBL PRX618S 18-inch, QSC HPR151i, and KW181 18-inch subwoofers, to name a few.