Active PMC v ATC : The Best Things… Part II

The Best Things, ( Come to Those Who Wait ) Part II
Or… PMC Twenty5 23i v ATC SCM40

Update on a previous thread and direction of thought.
Here is a reminder.

It takes time and patience to arrive at a great system.
It’s a journey, over time, with ideas and perspectives collected along the way. It’s also a symbiotic relationship with a good dealer, patient and happy to work with customers over time. As explained in my last post, the best things come to those who wait. Maybe true for both music lover and their chosen Naim dealer…

Last week, back at dealer Basically Sound, to collect something…
In fact, collecting our CD player - Naim CD5 XS - after some service work.

This being an ideal opportunity to spend some more time thinking about next steps, which is a new pair of floor standing speakers, for our current system at home.

Tony @basicallysound set up a demonstration system, for an afternoon of music and fun.
Which included our nDAC (brought from home) and CD5 XS, (already in the care of Basically Sound, awaiting collection), plus his showroom demo’ stock for SN3 + HCDR and ND5 XS2, to complete the set up we have at home. Tony - thanks for making it so easy.

So, the demonstration system used, same as at home, was as follows:

Digital sources
CD5 XS → DC1 →
ND5 XS2 → DC1 →
nDAC → HiLine →

SN3 + HCDR →

Image : our home system, set up in the dealer demo room.

Long Live the Humble CD
Having missed our CD player from home, the first thing done in the demo room was to play a few CD’s, (with PMC Twenty5 23i passive connected).

Really pleased to rediscover how good CD format can be and how brilliant this CD5 XS player is for replaying CD’s. Even better, as we have it set up as transport only, connected to an nDAC. Originally, we bought the nDAC as an upgrade for the CD5 XS and was reminded why. It’s just a brilliant combination.

After several tracks, couldn’t resist comparisons, with streaming and the ND5 XS2. Having swapped back and forth, playing same tracks, quickly discovered not much difference on 16/44. Maybe slightly different presentation. But not really much at all on SQ. Only when comparing 24/96 did any difference on SQ become apparent. That being a little more detail and nuance available in the recording.

In that moment, being reminded CD is still great format. So glad to get my CD5 XS back from some service work and looking forward to getting it home to play lots of CD’s.

Test CD tracks played, in no particular order…

Trentemoller: “Glow”, from Memoria, (2022)
Elbow : “Things I’ve Been Telling…. From Vertigo Audio, (2024)
The National : “Alphabet City” and “Coat on a Hook”, both from Laugh Track (2023)
Nick Mulvey : “Fever to the Form”, from First Mind, (2014)

But at the same time, I was getting used to the PMC speakers, as passive.

Speakers (again)
The main focus of the afternoon was floor standing speakers.
After much listening and thought, we are down to two options, which are :
(a) PMC Twenty5 23i ; (b) ATC SCM40.

Although we have done this before, about a year ago, (reported in my last post on this topic). In the meantime, PMC have recently launched active kits for their Twenty5 speakers. So, this time, felt it worthwhile to reconsider the passive versions and also compare active versions too.

( Note : For information, always been a fan of active, having run Linn Ninka as Activ and also Meridian DSP 7200 speaker system, both for long periods in a long musical journey ).

First was PMC passive.
Having already listened to a few CD’s to tune in to the room, system and speakers, then started to listen to several test tracks played from streamer combo’ ND5 XS2 + nDAC.

Image : PMC speakers, as passive. Also, cables ready for active connections later.
Plus, Rega items, on show, from a previous demo’.

Next was ATC passive.
The best way to share impressions on these two speakers, is by way of comparison. Comparing one to the other.

First, both are fine loudspeakers and could live with either model. Obviously, they do things slightly differently. So, the challenge is to decide which flavour is preferred?

Image : ATC’s as passive.

The same characteristics noting in my last post came to mind.
Maybe a second serious listen confirmed my earlier thoughts.

The ATC’s clearly have a strength in mid range. So, with acoustic material - voice, piano, cello, etc - all sounding superb. The mid range maybe being more apparent and a bit forward. ( Which I like, having lived with Epos ES14’s as best friends for many years).

I would also say they are an honest speaker, quite transparent. Playing familiar pieces, they reconstructed all of the recording with aplomb. Lots of “accurate” detail.

However, as before, I discovered the ATC’s need some power to get them moving. ( Maybe 10 o’ clock plus, on the SN3 volume dial). Last time, I found the same “sweet spot”. Once they are moving air, they really do rock. At this point, they become very enjoyable, with real authority. As music is often enjoyed at louder levels in our house, this is attractive. The downside is we also listen a lot at lower levels. In fact, most of the time as back ground. The ATC’s loose their magic at lower levels.

So, I’m starting to better understand forum comments about the SN3 maybe being underpowered with these ATC’s. I see they work okay. You could happily pair the two and just enjoy the music. But now understand the ATC design maybe needs more power to get their very best. Perhaps a NAP250 DR or better ? So, going to active version, with more watts available - later in the session - becomes an intriguing prospect…

The PMC’s do most things well, seeming to be better “all rounders”.
Playing music at lower volumes is more “enjoyable” too.
For me, I really liked their bass extension which is maybe an attribute of their Transmission Line design. They really reach quite low, subterranean, in an entirely satisfying way. Double bass notes, or kick drums or electric bass being sublime.

I’ve since read comments on the forum. The ATC SCM40’s appear to be well controlled, neutral speakers, you probably can’t go wrong with them. The only thing lacking perhaps is a full bass extension, they don’t go as deep as some other comparable speakers. Subs might be an option, maybe at more cost?

Lastly, the PMC speakers are more compact, easier (smaller ) in a room setting.

ATC active followed, which was a different speaker.
The weight of these speakers is obvious when they are moved about. They are hefty solid units.

Basically Sound have both ATC SCM40 passive and also ATC SCM40 active, in their demo stock. (Doing active ATC’s next, this also allowed some time for Tony to swap the passive cross over for active modules in the PMC Twenty5 23i’s, coming next).

Image : ATC’s as active.

The move to an active speaker was very impressive. Just more of everything.
From previous experiences, would suggest a bit like adding an external psu to a Naim item.

More power, more control over notes, a little more detail from the recording, better noise floor, etc. A little surprising was being able to hear the difference in the higher register, not just the lower notes.

Using SN3+ HCDR, comparing passive 40 vs 40A there was much stronger bass, more authority, overall very much better dynamics and bigger sound with the actives.

Yes, the active ATC’s do better with bass. But still need “winding up” a bit to get this going. They really rock.

Finally, the PMC Twenty5 23i’s as active now, were brought back into the room and swapped in to the system again.

Another noticeable improvement over the passive version.
Same basic characteristics, more control, grip, power, accuracy.
The music was more forward and at the same time, effortless.

Active & the Maths
Thinking about the two speakers as active…
My thoughts are the active integration in the ATC’s is maybe a more accomplished solution. (Compared to the PMC’s). It clearly has more power, as the power output from the internal active amplifiers is considerably higher. As a three way design, the ATC’s offer six amplifiers with higher output, six active cross overs and six drive units. All integrated in a coherent way. Not surprisingly, this is maybe reflected in the cost differential, as the active versions are £3,550 more than passive. (Prices current in May 2024).

The PMC’s are still good. A simpler two way design. Could easily live with these.
The active version can be bought complete for just £1,420 more than the passive versions.

So, costs and relative value for money are a consideration?

Even at £1,795, think the PMC active upgrade modules are exceptional value. (This option allows purchase of the passive model, then upgrade as retrofit, later, when budget allows). The difference and improvement in SQ is obvious and worthwhile. In my case, using the pre-section of an integrated amplifier, the improvement over the SN3 power amplifier section, plus then benefits of active integration were a positive step forward.

Both active versions were obviously so much better than their respective passive options.

Both actives had an appealing degree of realism and detail the passives couldn’t quite achieve, which was also an assault on the senses, but in a positive way. For less concentrated listening I would understand some might find this to be fatiguing. Personally, feel I could live with this, (for myself).

Like them both, for different reasons. So, still undecided.

Tony and myself debated the merit of active speakers…
Adding a better power amplifier is one simple way of improving SQ. Maybe adding a NAP250DR into this system would have a similar effect of creating more grip, better control, etc. All the characteristics mentioned above. This alternative approach might cost around £2k, (maybe at current pre-loved prices). However, also assume a separate power amplifier may not offer quite the same result as a properly engineered and integrated solution, combining separate matched amplifiers, active cross overs, direct connections to speaker drive units etc, etc. For SQ, active might be a better, more elegant execution of these inter-related items.

Box count and costs are also another consideration?

Food for thought?

Adding a Separate Pre
At this point in the late afternoon, we had already learned a few things with passive and active speakers. So, with a little time left in the day, we decided to add a separate pre-amplifier into the system. Which is one good reason for considering active speakers in the first place!

The PMC twenty5 23i active’s were left in place for what happened next.

Having left the room briefly, while Tony set up a NAC332, music suddenly started playing from afar. So, I immediately knew I was in for a treat before entering the room again. As the music playing was so much sharper, cleaner, easier. And that was from outside the room.

Image : Swapping NAC332, for SN3 + HCDR.

So, to sit down and listen to another 6-8 tracks, with so much more musical substance to enjoy, was a real pleasure.

What does a better pre-amplifier bring? To my ears, more details.
There was a little more information available on notes and with the timbre of instruments. The soundstage opened up a little, with space between the instruments. A bit more colour emerging in the sound scape. All together, as a whole, this makes for a more pleasurable listen. The music had more “boogey”.

At the time, I remember thinking, listening to passive to active speakers had already shown one significant uplift in SQ during the day. A second is a gift. That’s two big steps forward in SQ. The realisation of discovering two simple ways - in the day - to improve this system being awesome.

This experiment also proved there is a lot more music in the digital sources to be squeezed out. (And that’s before the nDAC has the benefit of an external psu too).

More importantly, this quick experiment showed that moving to a separate and better pre-amplifier is a viable option, with these digital sources and active speakers in place. A question being maybe NAC 282 or NC option NAC332, in time?

Initial thoughts on this, a pre-loved NAC282 being straight forward, by swapping SN3 for 282 and moving the HCDR over as psu, etc. Probably do this for not much money exchanged in a swap, with these two items. Moving to NC NAC332 maybe more expensive, so might take longer, but any cost being off set by swapping both SN3 & HCDR as a 332 has its own internal psu, etc.

One to ponder?

It’s All About The Music : Test Tracks
Test tracks used for the main speaker demonstration, in no particular order.
Most at 16/44 and some at 24/48 and 24/96.
Some old classics that have served well over the years, plus a few new favourites…

Go Go Penguins : “Wave Decay” and “Ascent” and “Friday Film Special,” all from From the North (live), (2024).
Blue Nile : “Tinsel Town In The Rain”, from A Walk Across The Rooftops, (1984).
The Bad Plus : “Everywhere You Turn”, from These are the Vistas, (2003).
Kate Bush : “Nocturn”, from Ariel, (2005).
Madonna ( feat. William Orbit) : “Nothing Really Matters”, from “Ray of Light” (1998).
Hannah Peel : “Sunrise Through the Dusty Nebula”, from Mary Casio : Journey to Cassiopeia, (2017).
Elbow : “Things I’ve Been Telling Myself For Years”, from Audio Vertigo, (2024).
Genesis: “Your Own Special Way”, from Wind & Wuthering, (1976)
The Crusaders : “Street Life”, from Street Life, (1979).

Next Steps ?
The 2024 objective is to add new floor standing speakers.
Next steps, when time allows, maybe a home demo’ in the weeks ahead.
I’m now thinking that might be the active versions of these two speakers.

Beyond that, still thinking a psu for the nDAC is likely the next move, next year or so.
However, now see an option for moving to separate pre-amplifier, which I will keep “up my sleeve” for the time being and think about this.

As always, my sincere thanks to Tony, for moving things around, being patient with my curiosity and answering lots of questions.
Also, several cups of tea, some cake, a few jokes and lots of great music too.

Finally, hope these thoughts are useful for others, with their own journeys…
After all, isn’t this the purpose of our great forum, sharing the joy of music and HiFi ?

Best wishes to all on a rainy day.


Image credits : Images by kind permission of Basically Sound


Giving that a like before I’ve even read the majority of it! Thanks for posting the experience, will sit down and read that at leisure later :slight_smile:

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Great, informative write up. Thanks!

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Hi @ratrat
What a great read! Thank you so much for such an excellent post and for taking the time to share your thoughts so clearly. This is an excellent example of the value of this forum and the many great folk who are on here. Brilliant job. Excellent choice of test music!!


Sure. Thanks.
We’ve touched on musical taste before :+1:
I’m sure we would have a lot to share, and enjoy, in a musical evening.
Music is such a brilliant hobby.

Happy listening

Super thx for sharing Your experiences.

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Thanks a lot for the wonderful review! Love to read! Exiting times when testing new gear

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I run active 40’s with a 552/NDS/555 and it works a treat. Prior to that I had a nap300 powering focal Kanta’s. I tried the 300 with passive ATC and the actives were so much better it was silly…. 300 was sold and I joined the world of active speakers.

I did find my ATC’s are quite sensitive to what they are fed and cabling / internet connections made a difference.

A pre and source or streaming pre with active speakers is an elegant solution…and ATC and Naim do that very well together.

Great write up, Tony’s customer service is second to none, it’s good to have a dealer of his quality in our good old county of Norfolk!



Thanks for that feedback :+1:

Think that comment maybe supports a simple hypothesis.
That is, all things being equal - with external power amps - an effective internal active design might be better?

In your case, ATC SCM40A active preferred to the entirely capable 300.

Interesting :thinking:
Helps me lean into active options

p.s. my early preamble matches your other point. Tony at BS is first class. Long term relationship are better and best.


Excellent write-up, thanks. G


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That’s the conclusion I made after listening to both passive and active and my very capable nap300 was partnered by super lumina interconnects and speaker cable and still got outperformed in every way by the active versions.

My suspicion is a lot of performance is lost in the cross over of passive speakers

Each to their own of course and tastes and room acoustics vary but for me active ATC and Naim work very well together.

I sort of get the low volume thing too but I have found that at relatively low levels of volume the music is just as enjoyable but it does sound better with the right level of volume.

I have added a pair of rel subs which work well with my set up so a consideration for down the line too.

This is thread is tempting me to look at the 50’s again now I have moved rooms….

Let us know what decide


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man, you took sh,t… out of this thread. this is fully detailed! great!

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Hi ratrat a superb write up of what sounded like a great day out, I have very similar thoughts to yourself direction wise, have added a 282 into the mix and intend to add a xps to the ndac then the next step will be exactly what you have been through, sounds like something to really look forward to.
Cracking job and many thanks for taking the time to post in great detail👍

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Interesting review @ratrat, I went from the PMC Twenty5 23s to the ATC 40A and pretty much agree with your views.


Now that is an interesting post. Thanks for sharing your insight.
So, different journey, but maybe same destination?

In our case, we need to do speakers. So that’s the next move. At the same time, attempting to make a choice with next few steps and an “end game system” in mind. It’s so tricky.

Wishing you the best with your own journey.

Fascinating feedback

If active module had been available for your PMC Twenty5, would you have explored that option?

I think I’m sold on active. Now just need to make a choice on which speaker ?

Best wishes

You have noticed one of the drawbacks with ATC as compared to PMC, that being the loss of resolution at low volume with ATC. I also found, having had ATC SCM40 passive and actives, they are brutal in their presentation of a poor recording. If you only listen to great recordings, then no problem. Unfortunately all great albums are not stunning recordings. :blush:


Nice that you thought it was fair analysis.
Thinking it’s fair too. In the final analysis, it’s a function of their closed box design and being less efficient to drive. They’re still great. Just now understand them a bit better for listening and studying.

Thanks for that.

Do you know if other speakers in the ATC range work differently. For example SCM20 Towers ?
50’s are ported. Have heard and liked these. But won’t stretch to that price point.

I have only heard 40’s from the Entry range. A fiend has the 19’s, but they are bit bright, especially as he plays Kate Bush all day……different strokes, for different folks. Get the right recording and volume with either version of the 40’s and you will find it hard to better for the price.

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Do not forget, that the PMC actives are using Class D amplification, whereas ATC are using Class A/B.

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