PMC Twenty5 / Twenty5i Active Module Review

What's an active loudspeaker?

A passive loudspeaker has a power amplifier connected to a set of components inside the speaker cabinet that separate the music frequencies between the drivers. These components are unpowered and sap power from the musical signal - typically they need to be quite large components to cope with the power flowing through them which leads to lower levels of accuracy in their manufacture and performance.

Done properly, like this option from PMC, an active loudspeaker means a set of powered crossover components fed from a pre-amplifier which send the split signal to a power amplifier dedicated to each driver in the loudspeaker. The powered crossover components deal with low power signal levels so can be manufactured more accurately and better quality crossover designs are possible. Sometimes the powered crossover and power amplifiers are external to the speaker, sometimes internal and in the case of the PMC Twenty5 and Twenty5i conversion they're a module which fits into the back of the cabinets, directly replacing the standard passive crossover panel.

Above I say "done properly" because some manufacturers (usually in lower priced products) call a loudspeaker active when really its just powered by an internal amplifier that drives a standard passive crossover.

So what are PMC up to with active modules in the Twenty5 and Twenty5i speakers?  The first of the Twenty series speakers were called just that - the Twenty range and they were launched to celebrate 20 years of the company.  In the domestic audio market I would say that this was the range of speakers that turned PMC from a respected but relatively little known manufacturer into a much higher volume well known brand.  Five years later they launched a replacement range called Twenty5 which had different cabinets across the board and then a couple of years ago these were tweaked into the Twenty5i range.

The Twenty5i range consists of a very small 2-way standmount 21, a large 2-way standmount 22, a slim floorstanding 2-way 23, a larger floorstanding 2-way 24 and the range topping (far more impressive as a performer) 3-way 26.  More details at PMC.

What's in the box?

There are 2 options here - you can buy a Twenty5i 21, 22, 23 or 24 speakers with the active module already fitted into the speaker in place of the passive crossover, or, if you already have Twenty5, 21, 22, 23 or 24 or Twenty5i 21, 22, 23 or 24 passive speakers you can buy the active module to be retrofitted by the dealer.  If buying a brand new speaker the active version is approx. £1500 more than the passive equivalent.  As a retro fit to an existing speaker the cost is around £1800.

Note that only 2-way speakers are currently covered by the active module.  The Twenty5 and Twenty5i 26 3-way speakers and the C centre channel are not included at the moment (even though the C is a 2-way design - I would speculate that there isn't room in that cabinet).  It seems that there's no current plan to add these models.

Demo

In the interests of transparency, I've not been a fan of the Twenty / Twenty5 / Twenty5i models with the smaller bass driver - ie the 21 and 23 models, even though its the 23 that's the mainstay of sales.

The demo system featured 2x pairs of Twenty5i 23.  Front end source was a Linn Selekt DSM streamer with the Organik stereo DAC module (approx £10k).  Output from this was fed to an ATC CDA2 combined CD player / pre-amp acting as a pre-amp (approx £3k).  The passive version of the speakers were driven by a Linn Akurate 2200 stereo power amp (approx £3.4k).

Our host played 3 tracks on the passive system - "Hey Laura" by Gregory Porter, "Here Comes The Sun (2019 version)" by The Beatles and "Happiness Is Easy (12" Mix)" by Talk Talk. Resolution is good, bass weight is fine for the size of the speaker but it feels a little "lazy". This is the main characteristic of the 23 models that I find to criticise - it just doesn't boogie, the music doesn't drive the along the way you might hope for a £4.5k speaker. Vocals are nicely resolved and have the emotion you'd hope for but are a little polite and recessed in the mix.

We get the first couple of minutes of Talk Talk again and then we swap from the passive system to the active system - the speakers now being directly connected to the pre-amp and the Linn Akurate power amp gets to rest a while. The speakers were positioned in the same marked location in the room (more on this later) and we went straight back to Talk Talk.  It only takes half the track to hear the differences the active conversion brings.  Everything is much more clearly presented - treble is tidier - bass is fuller and vocals stand clearly in the mix. Any downsides?  Probably not. The only downside we discussed between us was that perhaps the bass was a little too full - to be fair it would probably be worth experimenting with room positioning as this is a significant system change at play.  Remember here that we're looking at replacing a £3.4k power amp with a £1.8k active module.  That's not to say the Linn is a poor amplifier, its a testament to how fundamental it is to move the crossover from sapping power in passive mode to replacing it with far more accurate circuits in front of the power amp.  And I've saved the most important change to last - each driver has its own power amp and they are connected directly together - no power sapping passive components getting in the way.  And that will be part of the biggest improvement this option brings - the starting and stopping of the notes is in a different league, as is the impression of the music driving along - there's pace, dynamics and enthusiasm.  But its not aggressive nor wearing - we listened to another hour's worth of music and it was far more enjoyable - foot tapping in action.  It made a big difference to enjoyment of the music.

Conclusion

So no hesitation in saying this is a significant improvement on passive - and in this comparison, significantly better value for money.

Oh, and I've now heard a 23 I can enjoy :)

Thanks are due to Rob and Phil at Adventures in Hifi, Chester for the demo.  I'm sure they'll be happy to offer a similar demo for you.

Product Review: Songcorder Software by Meraki Acoustic

The Linn DS (digital streamer) family is, at the time of writing, just over 13 years old.  The first internationally recognised true HiFi company to take streaming seriously, Linn launched their top of the range Klimax DS as a market leader.  There have been several iterations since, all versions able to be upgraded to the current specification.

But the family has grown since then.  There are pure DS players (network connection, streaming capability, onboard stereo DAC), DSMs (all the above plus pre-amplifier capability, including analogue inputs) and other DSMs that do what DSMs do but have a built-in stereo power amplifier. Spanning the complete range too - from the designed-to-be-hidden Sneaky, through Majik, Akurate and Klimax ranges.  Most recently the  modular Selekt DSM has been launched which can be all sorts of combinations of streamer, pre-amp, all-in one stereo, all-in one surround sound and more.  Surround modules can be added to DSMs too. Then we throw in the choice of outputs - traditional stereo analogue, Linn proprietary Exakt digital link to Exaktboxes or Exakt integrated speakers and a combination of analogue & Exakt on some units.

That's probably pretty confusing to the uninitiated, and understandably so. But there's even more to it than that. Software. Without software these players would be expensive (or very expensive) decorative (or in some cases not so decorative) items.  The software that makes them operate is vital.  But one of the beauties of the Linn DS / DSM is that the software continues to evolve. And every DS / DSM since that first one back in 2007 is capable of being upgraded to today's software versions. And Linn releases the software updates without charge. That's right, a 13 year old product is still being upgraded by Linn on a frequent basis - and it doesn't cost the original, nor subsequent, owners a penny.  Buyers need to keep that in mind when they think Linn gear is too expensive. Some of these software releases have unleashed even greater sound quality and musical enjoyment from the streamers, not just new functionality.

So even though Tidal and Qobuz streaming services weren't available back in 2007, they are available on the DS/DSM today through those software updates. As is the ability to tune the output of the music to counteract the worst impact of the room on your music.

Why do I mention all of this? Well where there is software, there needs to be ideas. Creative ideas. Ways to make hardware perform tasks that weren't originally envisaged. New ways to exploit, new services to offer, new functionality for the user. And that's where Meraki Acoustic comes into the Linn DS/DSM picture.

Many of the DSM devices have a built-in analogue turntable input - MM or MC - and this was the inspiration behind the Songcorder app from Meraki Acoustic. The DSM turns that incoming analogue turntable sound into a digital signal. What if there was a way to capture that digital signal, feed it to a computer and capture it as an audio formatted file? Could that be a way to digitise all that precious and delicate vinyl? Could a DSM customer capture their favourite music in format that doesn't wear out? Would they finally be able to get that vinyl only release from 1976 into a digital file to listen to on the move, in the car, in rooms without a turntable?

The answer is yes - with Songcorder.  Meraki kindly sent me access to a copy to download to investigate further.  As most will know, although I have a turntable, its not the main source in my system.  Even so, I thought it would be interesting to give Songcorder a try.

The download was easy as was install on my up to date version of Windows 10 running on a Dell Latitude E6440 laptop which has a 3 year old Core i5, 8GB of memory and an SSD.  I tested it along with my Ariston RD80sl / Linn Basik Plus / Goldring 920 turntable and my Linn Akurate Exakt DSM through its built-in MM phono stage. The instructions recommend a wired connection for the computer running Songcorder and for the DSM - wifi being "potentially" troublesome.  In practice I found wifi to be almost always troublesome so stuck with an ethernet cable throughout, which was totally stable. Your DS or DSM must have Songcast enabled for Songcorder to do its thing.  It must also be listed in the compatible devices list here: https://meraki-acoustic.com/songcorder/#Compatibilty

If you're as old as I am you'll remember pressing pause and record on your tape deck, gently lowering the stylus onto the record and then pressing the pause button before the track started - the way we used to be able to play our own music in the car or the kitchen or later on a Walkman or similar.  Well Songcorder is similar in concept - whatever you're playing through the DS or DSM will be captured and recorded as a digital file ready for use with your streamer or loading to your DAP.

Once installed and fired up, this is the simple interface: 

Select your wired connection in the Network Interface drop down, select the Linn DS/DSM you want to record from (the software found all 3 Linn devices on my network) and select which directory you want to drop your recording into, and that's it. Nothing fancy but nothing complicated nor confusing - refreshing.  I really like the simplicity.  Start your turntable playing and click on that big red button. Done. Of course, you need to keep on top of what's going on.  You could record a whole album side and leave it at that. Or you could then use some software tools to break down the side into individual tracks. Or you can do what I did and capture individual files for each track on the LP.  When recording you get the simple screen below, just click Stop when you're done.

For each vinyl recording Songcorder creates a file at 24 bit 192kHz resolution using my Akurate Exakt DSM - I suspect that this is the resolution used by Linn when converting analogue to digital. Recordings from earlier Majik DSMs would be resolved at 24 bit 96kHz due to its lower resolution ADC stage. Songcorder generates what looks like a unique filename in FLAC - a widely supported format that can be converted to other forms by many of the popular digital music file handing programs available. You'll need a music file editor (I use TagScanner but there are lots of choices) to rename the tracks and input your own meta data such as Artist, Album, Track, Year, Genre etc.

Only one element of Songcorder I didn't enjoy is that it goes back to its default folder every time, rather than remembering where you prefer to capture your recordings. Its a very minor point and doesn't take away from the fact that this is a superbly simple tool that does exactly what it sets out to do.  The good news is that this gave me the opportunity to test the bug reporting process and happy to say that work is underway to address this as I type.

Sound quality is excellent - when playing back a vinyl recording, as far as I could tell, there was no degradation from the original analogue conversion I was listening to as recording took place. 

Whilst vinyl is the inspiration for Songcorder - to preserve those rare recordings or to create back up copies, for example, I did find that Songcorder will capture any stereo audio input on the DSM that's connected by toslink, SP/DIF or analogue inputs. Streaming works, but HDMI was less successful - theoretically it should work with stereo unencrypted content, but I didn't find any. Streaming works equally as well as the analogue input and captures the file in the resolution of the original source.  Of course an anlogue stereo output from such devices would work. Songcorder picks up the signal before any of Linn's SPACE Optimization or Exakt processing is applied.

Of course, one should be careful about copyright issues and only capture music already owned, or material that is free from copyright. 

An impressive piece of very effective software - I was so pleased by its performance I have purchased a copy, an equally smooth and simple process. At the time of writing the software cost a mere 20 Euros and is highly recommended.