Loudspeakers

The ever-changing shape of hi-fi systems has been something of a boon for active speakers. As well as the rise of the self-contained ‘smart active’ speaker, in a world where large swathes of source equipment is also a preamp, more conventional active speakers are also seeing a resurgence. PMC has considerable experience in this field, but the bulk of its active models keeps the amplification external – simply using a powered crossover in front of it.

The latest offering is a little different. It makes use of the existing twenty5i models and places the amplification within the cabinet and it quickly becomes clear that the passive speakers have been designed with a view to this happening. What appeared at the time to be an odd styling flourish of using a massive metal plate to mount two small speaker terminals on the passive model turns out to give PMC the room it needs to build an active module in the same space. To simplify this further, there is only one module for four models (which is why the 21i, the smallest speaker in the range still has the whopping back plate). Before it is screwed in place you can select which model you have via a dip switch and the crossover will set accordingly. It then attaches via an actual connection rather than needing any soldering.

The module itself contains both the powered crossover and a pair of 100W Class D amps – one per driver. This doesn’t sound like a vast amount when you look at some of the numbers being bandied around, but with a relatively sensitive input the PMC should not have any headroom issues in the real world. This is made available to a single RCA and XLR input per speaker. Unlike ‘smart’ rivals, the PMC is dependent on external inputs to function but, given how many candidates there are for that, it’s not much of an impediment.

The active 23i is mechanically identical to the passive version (HFC 473). It is a compact, two-way floorstander that makes use of a 19mm tweeter with a rolled surround making it 34mm across in total. This hands over to a 140mm long-throw mid/bass driver. The relationship between the two is quite unusual. They crossover at a low 1.7kHz in a more substantial and structured manner than many products from notional rivals. Like all PMC speakers, the low end is assisted by a transmission line that is 7ft 8in long and features the proprietary ‘Laminair’ vents at the end to control the flow of air leaving the cabinet.

It’s important to mention that if you are reading this in possession of a pair of passive twenty5i (or indeed the preceding twenty5 models) and are thinking: “I wish I’d known there would be an active version”, the good news is that the active modules can be retrofitted to existing passive cabinets at a cost of £1,975. Even so, it’s not hard to argue that the £6,575 asking price of the active 23i is pretty significant – taking it relatively close to offerings from companies with an equally formidable reputation in active loudspeakers.

In terms of how it is built and finished, however, you can see where some of the money has gone. This is a small and unobtrusive speaker, but it has a significant and appealing level of presence. You don’t have to be invested in acoustics to know that this is a pretty serious bit of kit. Details like the damped metal spike bars and adjustable spikes speak to a thoroughness and attention to detail that will win over more than a few people and both the wood options and the Gloss Black feel like they have been executed to a high standard.

As luck would have it, I have also tested the passive version of the 23i in the same room as the active version – which provides a useful point of reference. It quickly becomes clear that the move to active operation doesn’t change the character of the 23i – instead it serves to frame and focus it even more.

Sound quality

It also maintains an element of the presentation that really made itself felt with the ‘i’ versions of the twenty5 Series. The gorgeous soundscapes of Zola Blood’s Black Blossom, extends well beyond the cabinets without ever sounding vague or diffuse. What I also find impressive is that it is able to repeat this in two different test locations without any huge effort put into placement. Not too long ago, PMC speakers could do some amazing things, but they required you to put the effort in. Now they do the same things, but in a more fuss-free way.

Where the 23 Active really steps up over the passive version is that some of the slight forwardness with some amps has been entirely eliminated. As PMC has had complete say in how the amp modules behave, it means that even when pushing the 23i Active hard with the shouty but magnificent Superabundance by The Young Knives doesn’t see you wanting to back the volume off in any way.

Interestingly, something I’ve long regarded as a slight shortcoming of the 23i might also have been dealt with too. Pushing the speaker at high levels with bass-heavy music can result in the bass taking on a quality that isn’t so much the port becoming audible, but there being a sense of air moving to help achieve it. I had felt that this was a baked-in element of the performance and something that’s an acceptable trade-off for the sheer heft that the 23i delivers. The presence of the Bluesound NODE ICON on test at the same time – able to function as a preamp with Dirac room optimisation – demonstrates that this need not be the case. It tightens up the low-end of the PMC considerably, keeping the impact but tightening up everything to be even cleaner and more potent. I suspect that the same can also be achieved with a little room treatment if you’re invested in extracting the most from the PMC.

I reckon quite a few people will want to put that effort in too. This is in its own way every bit as clever and modern a solution as the self-contained wireless active speakers because the nature of its control point – be it classic analogue preamplifier or modern streaming preamp – can be chosen in the context of what you need in your home.

Conclusion
It certainly isn’t cheap, but the twenty5.23i Active demonstrates a means of combining the performance the company is renowned for with a level of convenience and user-friendliness that will allow it to work in a huge variety of different systems. It’s a brilliant update to a well-regarded speaker and PMC deserves to do very well with it. ES    

DETAILS
Product: PMC twenty5.23i Active
Type: Two-way active floorstanding loudspeaker

FEATURES
● 19mm tweeter with 34mm surround
● 140mm midband/bass driver
● 100W Class D amplification per driver

Read the full review in  Issue 527