"What a refreshingly honest blog about listening to music through hi-fi. So happy to see views based upon the enjoyment of music rather than so-called sound 'quality'." - Peter Comeau, Director of Acoustic Design at Mission / Wharfedale
Showing posts with label 250DR. Show all posts
Showing posts with label 250DR. Show all posts

Monday, 25 January 2021

System Synergy and Expectation Bias

A couple of phrases you might hear or read from time to time when researching or in dicussion about music playing hardware.  What are they about, and why would I be writing about them right now?

Sometimes how to phrase an audio experience is very elusive.  Some readers might say that continues to be the case, even for published posts!  This particular case has been more elusive than usual - its been a year since I made my notes on this project. How to frame those notes have been through about 6 iterations and I'm not sure I'm there yet. But a lot of time and effort went into this, and its time to just put it out there, good or bad, as the products involved might be old hat before I'm content with the wording.  I wanted to not just list the reviews, but to try and put them into some kind of relationship - finally settling on the synergy and expectation bias frame to hang it all from. So here it is, some kind of a review from circa Christmas 2019:

A 6 week or so period of frenzied (at least by my standards) box swapping, mostly for research purposes, but also to inform some purchasing options, mainly not for me, but for a good friend of mine, who's system features here. And it's all given the opportunity for another few blog posts too.  Elsewhere on the blog you'll soon find some impressions of some of the products involved so I won't go into huge amounts of detail here, but will cover a "flavour" of the systems involved. Long form, no photos and no apologies for that.

Coming to Terms

What do these words mean, in an audio system context?  Well, let me have a go at describing how I would use them, so these aren't definitions as such, but more setting the context of this post.

System Synergy - when putting together a whole series of components into a system - CD player, turntable, amp, speakers, cables, the room - do they work together in the way you would like them to?  Or do they lead to some kind of imbalance in a system?  Do you hear a coherent musical message, or is there something that grates like a bloated bass when you wanted tight tunefulness or a laziness to the sound where you wanted pace and energy?  Well, when it all comes together to meet your hopes, that, to you, would be a system that displays good synergy - the components complement each other to give an overall positive result.  If it doesn't work, the synergy's not there, then there needs to be a further search to find what's causing the imbalance, to work out what needs changing or improving.  Note that there is no mention of cost in this description - it has nothing to do with cost, it has to do with balancing characteristics of components to get a good result.

Expectation Bias - we'd probably all like to think we're impartial and can evaluate what we're hearing without regard to what we think we're going to hear or prefer.  Are we going to prefer one brand over another because its been a favourite for years? Are we going to like the sound of the component that has the nicest finish or a preferred species of wood on the front? Will we expect the more expensive bit of cable to sound better than the cheaper one?  Of course we all have these biases - its part of what makes us human.  I think its possible to try and minimise them by being concious of the issue, but probably not to eliminate it.  Blind testing (where you don't know which component is playing) is often advocated, but it just introduces different problems (such as an unnatural focus on the listening process), so I don't consider it to be the answer.  Just accept that a level of bias is inevitable and that it influences your opinion, but try to minimise this as much as possible.  That's one of the reasons why this blog is just opinion - there's nothing scientific about most of it, and that's just the way I prefer to keep it - the disclaimers make this clear.

So How?

If we're susceptible to expectation bias, how do we know if a system really has good synergy or if we're just expecting it to have good synergy?  Well I don't think there's a way to be totally objective (objectivity is restricted by the measures used anyway, as there's no way of knowing if a set of measures is comprehensive or relevant enough, that's why science keeps evolving) so just embrace the subjective and try to deal with it.  Its also worth noting that listening to music is meant to be an emotional experience and therefore, to me, it seems that choosing a system on some level of emotional evaluation is entirely reasonable.

Rooms

Mustn't leave the room out of the equation either.  Lots of impact on the way a system sounds comes from the room and the interaction of the speakers with the room, so I've included that in these musings to try and cover a little of the less obvious.  Where possible (ie with the Linn front end) SPACE optimisation was set up for each system.  What is often referred to as "Tune Dem" or "Tune Method" was used to position speakers and adjust SPACE.

Expectations

I'll go straight into listing the systems that I listened to over those few weeks a year back and that have fed this post, along with my expectation bias - as without that the rest of the post will be a bit meaningless.  The premise of the post being that my expectation bias wasn't met and I'll describe where and in what way.  Perhaps this is part of trying to be aware of my own bias and trying to rationalise how I have, at least partially, probably, tried to put it to one side and listen to what's actually going on. Still a big "if" though.

Systems

I won't go fully into every detail of the systems here, such as precise cables etc., but the main components that differentiate the systems.  I suppose its fair to say that my expectations are in comparison to my everyday system.  They're based on a mix of hearing 2 of these systems frequently and hearing the other components in other systems. It is fair to say that every single one of the components in these systems is highly respected, so there are no "duds" at all, and that's where the synergy element becomes so intriguing.

System 1: 

Melco N1ZH server, Linn Akurate DSM / Exaktbox Katalyst streamer, 3x Lejonklou Tundra Stereo 2.5 power amps, PMC Twenty.26 converted for active use, medium size pretty much rectangular room. This Exakt system uses filters for the PMCs available from SpeakerFilters.com, not the standard versions.
Expectation Bias 1: this is my everyday listen - its taken a long time to get to this system - it has a great deal of  detail but also a very musical flow to it.  Its not the last word in dynamics and slam but I can listen to it for hours (and do so, most evenings), following the tunes, enjoying the emotional impact of the music.  Its not perfect, no system ever is, but its what works very well for me.  What's my expectation?  Well, its more a reference point for comparison than an expectation really, but I would say that I expect it to be very difficult to beat in this evaluation with other systems having some benefits but not the overall balance of this system.

System 2: 

Melco N1ZH server, Linn Akurate DSM / Exaktbox streamer, 2x Lejonklou Tundra Stereo 2.5 power amps, Kudos Titan 505 on their dedicated stands and configured for active use, medium size pretty much rectangular room
Expectation Bias (comparative to System 1): more detail, a more dynamic presentation, a touch of brightness. Perhaps a little looseness in the bass.

System 3:  

Melco N1ZH server, Linn Akurate DSM / Exaktbox streamer, 2x Naim 250DR power amps, Kudos Titan 505 on their dedicated stands and configured for active use, medium size pretty much rectangular room
Expectation Bias (comparative to System 1): more detail, a more dynamic presentation, a touch of brightness, possibly assertiveness approaching aggression, more impact in the lower frequencies.

System 4:  

Melco N1ZH server, Linn Akurate DSM / Exaktbox streamer, 3x Naim 250DR power amps, PMC Twenty.26 converted for active use, medium size pretty much rectangular room
Expectation Bias (comparative to System 1): a more dynamic presentation, a touch of brightness, probably assertiveness approaching aggression, a loss of musical flow.

System 5:  

Naim NS01 server, Naim NDS streamer with 555DR PSU, Naim 252 pre with PSU, SNAXO crossover, 2x Naim 250DR power amps, Kudos Super 20 configured for active use, a medium sized room but L shaped, using the larger part of the L, which is smaller than the other listening room.
Expectation Bias (comparative to System 1): a system I'm already very familar with - a more dynamic presentation, too bright for my taste, assertiveness approaching aggression, a loss of musical flow somewhat compensated for by the enthusiasm.

System 6: 

Naim NS01 server, Naim NDS streamer with 555DR PSU, Naim 252 pre with PSU, SNAXO crossover, 2x Naim 250DR power amps, Kudos Titan 505 on their dedicated stands configured for active use, a medium sized room but L shaped, using the larger part of the L, which is smaller than the other listening room.
Expectation Bias (comparative to System 1): a more dynamic presentation, slight brightness, assertiveness approaching aggression, perhaps retaining the music flow, extra weight (because of the smaller room mainly), more information delivered.

So there we are, cards on the table. Something else worth mentioning - those who say "all competently designed solid state amps that measure within a gnats whisker of measurement-of-the-week all sound the same".  I have an expectation bias about that too - its just not true - I've heard far too many amplifier changes in systems to know that this is not true.  Unless I've only ever heard incompetently designed amps with bad measurements, which is also not true.

LISTENING WITH BIAS, OR NOT. MAYBE.

So here we go, here are the descriptions of systems 2 to 5 and a conclusion, that's not what I thought it was going to be:

System 2: the biggest suprise for me really.  The Titans give a far more detailed presentation than the PMCs, its suprising how much more they reveal in the recording. The extra brightness is certainly there, as per expectation, but is this just brightness or is it more detail too?  I'm going with the latter as there's more expression too in the vocals.  In fact the greatest strength of the Titans in this and the other systems is their vocal expression - its quite outstanding by any standards of the many systems I've heard.  Another element that was as expected is that, compared to the Titans driven by the Naim amps, there is a softness in the bass with the Tundras.  And here I think we see the first of the synergy issues - perhaps the Tundras and the 505s don't sit all that comfortably together as there was another element here that I wasn't expecting as the Tundras have never sounded like this in any other system I've heard - a sense of relentlessness.  Not shouty aggression, just a bit too much going on and losing some of that lovely flow that the Tundras present in partnership with speakers such as the PMCs and Graham Audio LS5/9. That, juxtapositioned with the lack of pace in the bass lines, meant that this wasn't the best of the combinations compared here.  There was a fair bit of experimentation with toe-in with the Titans in this room as there's definitely not the width or precision of soundstage compared to the PMCs. Don't get me wrong, we're talking about a decent sounding system, but in absolute terms, it lacked the right synergy.

Expectation bias 0: Systems 1

System 3: its long been a thing, a Linn front end with Naim amplification into a pair of speakers of choice.  Traditionally, of course, that was an LP12 and a passive Naim pre-power combination. Here we bring the tradition up to date with Linn streamer/pre and Naim power. Yep, more impact in the lower frequencies, no doubt about that - nearly reaching as low frequencies as the PMCs too - impressive. Mind you, the 505 standmounts on their dedicated and structurally massive stands are actually much more intrusive in the room than the much more constrained PMCs (which I always use the the grilles on). Definitely more detail from that (very) expensive tweeter - is it too bright? Its touch and go and track dependent, sometimes just tipping over the edge. But here's the thing - music, because listening to the music on this combination was very engaging - but its different to the regular system 1. There's an immediacy without shoutiness and that detail mentioned earlier but there's not the same musical flow that a Tundra delivers (in partnership with speakers they work happily with!). Whilst the Titans have very impressive bass power and immediacy, they still didn't quite fill the room like the PMCs do. Vocals are excellent again and there's plenty of engagement into the meaning of the music. This is good, but is very much along the lines of the expected.

Expectation bias 1: Systems 1 

System 4: before I go any further, just consider this: moving from Tundra to Naim power amps is a 50% price hike in amplification prices. And they do have a very different mix of abilities. I can also say that the Naim NAP250DR is a heavy beast.  Not too easy to lift onto a shelf and keep the shelf edges in pristine condition.  Those massive toroidal transformers are very heavy indeed. And noisy, good grief they're noisy. Not through the speakers, no issues there at all. But my goodness do they hum. I know my incoming mains typically carries about 2.5% distortion (the PS Audio regenerator displays this information) - I'm not sure if that's high, typical or low, but its certainly enough to get the NAPs a buzzin'. Just to be clear - neither of the power amps in this sequence of tests were plugged into the PS Audio, only the low current source electronics are fed from the regenerator. So there is no doubt that the 250 boxes have a tighter grip on the PMCs. There is more slam, there is more immediacy. There is a little more enthusiasm in the upper frequencies but it never becomes wearing in this system. All of this as expected.  What I didn't anticipate at all was the way everything hung together as a piece of music in very much the same manner of the Tundras into these speakers. Even that very taughtly controlled bass didn't disrupt the ability to follow the tune. Very good indeed. Except for gaps between tracks when the boxes from Salisbury irritated me significantly. Expection or surprise - calling this one a score draw.

Expectation bias 2: Systems 2

System 5: nearly all change.  Change of front end, speakers and room. As I'm very familiar with this system as it as grown and developed over the last 5 years with the Super 20s, then my "expectation bias" notes above are really all you need to know - they're more about experience than expectation. So let's call this one a no score draw!

Expectation bias 2: Systems 2

System 6: Would we expect (or have a bias!) that the 70% more expensive 505 with their stands would have a family feel when contrasted with the Super 20 floorstanders? Would there be a family resemblance from the North East parentage? Yes. And No. The Titans have that same family immediacy but the way they feel more "grown up" was far greater than my expectations.  Especially in the treble - where the Super 20 appears to major on detail, I find it gets too much after a while. What seems to be the case with the 505 is that the detail is real and it knows that it doesn't have to try too hard. I was a little worried about the size of the bass that comes with the upgrade to Titan (yes, the standmount has far more bass output than the floorstanders, in part due to their isobaric loading) in this smaller room, but it worked very well indeed - and there's an important reminder that system synergy includes the room.  Here, of course, there is no SPACE optimisation to make the best of the room so its all down to component choice and speaker positioning. What was just a touch underwhelming from these speakers in the bigger room is just right here. I don't get the same sense of ease of musical delivery compared to the Linn front end with Naim amps and these speakers, but I can see how their immediacy could appeal. No stridency, no experience of fatigue.

Expectation bias 2: Systems 3

OUTCOME

So you can now decide if any of this tells you anything about expectation bias or system synergy (which needs to include the room).  I certainly was surprised that the weight of the 505 could work in the smaller room, that the Tundras and Titans just didn't get on together at all and that I'd enjoy the Naim power amps in my regular system anywhere near as much as I did.

I wish the Naims amps didn't have 2 faults: that hum I can't just dismiss nor excuse, and their price. So I shall continue to be extremely happy with the Tundras as they work very well indeed with the PMCs.  As for my friend with the largely Naim system - he bought the 505s and has them working even better now the speaker cables are Super Lumina.

Saturday, 23 September 2017

ACTIVE SERVICE - Naim with Kudos T-707

Yesterday Acoustica Hifi in Chester had a Kudos open day.  T-808, T-707 and T-606 were on offer.  Thanks to Acoustica for the invitation.

I turned up towards the end of the day and all three pairs of speakers were crammed into the room.  A big sounding Deadmau5 track was pumping out and I assumed the T-707s were in action.  However, local Naimist R was sat there having a listen to the T-606s in passive mode - so a very impressive introduction.

There are quite a few reports on Audiophile Musings about the development of the Kudos Titan family, most of them are here:

Acoustica Show 2015

Acoustica Show 2017

Munich High End Show 2017

National Audio Show 2015

Indulgence Show 2016

The T-606s tonight were not ideally placed, in fact it was remarkable that they could sound anything like decent, given their position in the room.  Just enough to get a taster.  They did not disappoint and their performance here (being driven by an all Naim system, culminating in a 300DR amp and SuperLumina cables) just reinforced the view of their performance in Munich back in May.

T-606 in the centre flanked by T-707 and the T-808s on the outside


But the main course tonight were the T-707s, the mid-size speaker in the Titan range.  If you look at the above links, you'll find much praise for these speakers.  They don't have quite the finesse of the 808 and they don't go quite so deep, but boy do they boogie.  There's a real sense of fun in what they do - they party and let the music flow along very well.  Back at the Acoustica Chester show in March, they were driven actively by a development Naim SNAXO crossover.  Here they were in a similar set up, but the SNAXO has been back to Naim for some tweaks to the components and the box is now described as pre-production.  Hopefully Naim will find a slot to crack on with production soon.

The room was joining in quite a lot tonight, so conditions weren't perfect, and some tracks from Tidal sounded good (the Deadmau5, Kiasmos, for instance) and some sounded pretty ropey (for example, Eric Bibb).  So for proper listening we focused on locally stored rips on the NAS.  Daft Punk's "Georgio Moroder" and a Janis Ian track that I didn't get the name of were used for the focussed listening.  After enjoying the 707s active for a while, it was time to get down to a worthwhile comparison, despite the rather compromised room setting, at least the comparisons would be on a consistently inadequate set up and could therefore deliver a level playing field.

The speakers were switched back to passive.  As is usual with the Titan range, this just involves a few u-shaped metal links - with the links in place the internal passive crossover divides the signal between the drivers - remove the links, hook up 2 stereo power amps and the splitting of the signal needs to happen before the power amps - in this case a Naim SNAXO.  This SNAXO is now described as pre-production and will work with T-707 and T-808 with a small tweak to one of the internal potentiometers.

In passive form, the Janis Ian track was a pleasure to listen to.  The room was joining in to an extent but it was easy to hear that and ignore it to get to what was going on directly from the speakers.  The track is fairly funky by JI standards, which is to say its a not very funky track by funky standards, but there's some decent electric bass lines along the way.  The track starts quietly then adds extra instruments and complexity along the way.  The music was joined up and enjoyable in passive form, bass tuneful, imaging is good but not exceptional (but hey, look at the way they were set up on this occasion, that's no surprise), vocals nicely rendered - this is a very good pair of speakers in action.  We listen to the whole track, then go back and listen to the first 90 seconds or so to try and get the beginning of the track stuck in the memory.

Conversion to active takes a couple of minutes.  Understanding the magnitude of the difference it brings is a matter of seconds, then, as the track plays that understanding develops and deepens.  The active conversion brings much of what I'm used to hearing in equivalent changes in Linn active systems.  Its that clarity thing, the edges of notes are better defined, instruments start and stop with more conviction, the bass lines are crisper, tunes are easier to follow, the reverb on a guitar goes on that much longer but doesn't crash into the other instruments, there's a space between and around each instrument that wasn't there before.  Ian's vocals are better rendered, they've taken a step forward from the mix - there's subtelty in there that wasn't there before.  But all this is still joined up as a single musical message.  Back to that first few seconds of going active, and the thing that I really wasn't expecting but was quite a stunning change - the Ian track has a number of quiet elements right at the beginning of the track and that quietness was soooo much quieter than before.  With passive, I wasn't really concious of any background noise and hash in those quiet elements, but with active, the lack of that noise is very apparent (I'm sure there's still some there, but its notably less obvious).
I wish I'd made a note of this track - I've been trawling through the Janis Ian tracks on Tidal, but its a long list and I haven't found it yet!  I have discovered lots of tracks that I like along the way though, so that's a plus.

We then listened to the Georgio track and the way these active 707s can power through this piece of Daft Punk inventiveness is very impressive.  The intro clearly reveals the sounds of the 3 different mics used to record it, and the chatter in the background is easy to follow.  But the real test of this track is about 3/4 of the way through when the very complex bass lines play at tremendous speed and there majority of systems just can't do this bit very well - they end up playing monotone thumps rather than several complex and tuneful notes.  The active 707s do a great job on this not only maintaining the tune but revealling a really growly edge to the note, far better than some more expensive systems.  And playing loud doesn't phase them at all.

So, for me, an easy conclusion to reach.  But here's the sting in the tail, that will be of interest particularly to Naim system owners.  The passive system was using a single NAP300DR with Naim's expensive SuperLumina speaker cables.  The active system used 2 of the "lesser" NAP250DR power amps and the far more reasonably priced AudioQuest Rocket speaker cables.  Game set and match to active!  Get that SNAXO on the production line Naim!

Thanks to the gents from Kudos and Acoustica.

I look forward to giving the T-707 a listen in my Linn Exakt system - I think they could be on the Musings system roadmap.  Just need Kudos to finish up the Exakt crossovers in the next few weeks.

Thursday, 30 March 2017

Linn Exakt and Kudos Super 20: World First Review

There's a bit of a back story, so please bear with me.

First, I'm going to assume a working knowledge of Linn Exakt and what it can do to process the musical signal coming from a DAC, through a set of power amps and on to each driver in a loudspeaker.  If you're not so sure, you can follow these links for some more information:

Also, there's lots on the blog about my current system of Linn Akurate Exakt and PMC Twenty.26 which forms the basis of comparison here, so have a dig around if you need to catch up on the reference point for this review.  But before the PMCs, I tried some different options, one of which was the Kudos Super 20.  At the time, this was with a Linn Klimax system using a more traditional, passively driven, approach.  That review is here, but to summarise on my view of the Super 20s in that system in my room:
"So its a mixed bag.  I really understand why they're a good seller and why their owners enjoy them so much - I get the appeal of the etched instruments, I get the speed, I get the way they do female vocals. If I was in the market for speakers at this price point, I would say that they could be on a short list. But I need to relax into my music.  I like chilled out music to wash into the room and give a warm feeling as I sit back after work and wind down. When a system doesn't let me do this, its not right for me.  Others will have a different view.
As such, these aren't the right speakers for me or my room.  They're different to the M140s, but they're not the right mix of abilities to justify a change to the Super 20s.  I'm looking for a bigger difference, but perhaps, more of what I have, rather than a different direction."
 
So not a ringing endorsement in my system and room, but certainly something to consider in the right size room - they work well in their owner's own listening room which is somewhat smaller in volume than my own room.

Kudos Get Activated
Since then, Kudos have committed to delivering all their "upper" range speakers (at the moment, that's Super 10, Super 20, T-707 and T-808) with the ability to run with active amplification - ie, the passive crossover in the loudspeaker is by-passed, an active crossover is placed in front of the power amplifiers and each power amp channel controls just one driver each. This has been successful for T-808 with both Linn Exakt and Devialet implementations which you can read about at those links. Most recently, I had my first taste of Kudos's newly launched T-707 being partnered with Naim electronics including a SNAXO active crossover. This is a deeply impressive combination, heard at the Chester Hifi Show 2017.

A little while ago, the Super 20 (re-named 20a) has been treated to the Kudos connection panel which allows passive or active use of the speaker. Conversion from passive to active is extremely simple - just pull out 4 jumper hoops and connect your amps to the appropriate driver connections. So simple, in fact, that Kudos don't explain how this is done on their instruction sheet. Perhaps there is an expectation that the dealer is involved in most installations.

New Kudos Super 20a ready for listening
 Review Caveats
There are a couple of caveats to this review to bear in mind. First, and crucially, we had a pretty much brand new demo pair to work with. So new, the Cherry veneer was still very pale indeed - I know this darkens over time to something much deeper and richer. We estimated the speakers had about 50 hours of use on them - this is important to bear in mind as you read the review, as speakers often take a while to settle down or 'break-in' from new and their character can change a surprising amount over this time. Second, we only had a 3 hour window to work within, so there's a chance there may be more to come given more set up time - on this one, we saved a good chunk of time by going straight to the speaker position we'd found had worked best for the speakers in passive form. I think that's a very reasonable approach to take and should result in something pretty close to optimal.

Local friend R has earlier passive Super 20s in a Naim NDS/555, 282/Supercap DR and 250DR system with SuperLumina cables throughout. This lot feed a pair of the earlier Super 20s which don't permit active operation. This means there are 2 of us with experience or extensive experience of the Super 20s in this system. R's Super 20s are the ones reviewed in my previously passive Linn Klimax system. This gave the opportunity to directly compare the brand new speakers against a set with thousands of hours of use. Hence the first caveat - straight out of the box the newer pair were over bright and the bass was 'stiff' and inarticulate in comparison. To the extent that both of us found listening rather tiring. So they were left playing away to themselves, facing each other with one out of phase to reduce the amount of sound they produced. This is how we know they have at least 50 hours of music under their belts.

Set Up
Distinguishing the Super 20a from the Super 20 is the connection panel. At the base are the normal single-wire passive inputs. The second row down are normally vertically linked to the top row by u-shaped links during passive operation.  Here the top row of connections are being fed active treble and bass signals from Naim SuperLumina cables.

So some perspective from the above in the context of a familiar system and a current (very happy) owner.
2 days later and they're set up in the Musings listening room, positioned where the passive pair had sounded best. A quick look at the brief instructions soon told us that we had to work out the active connectivity ourselves, but it is simple. Pull out the 4 connecting loops and hook up the correct speaker cable to their respective 'active treble' or 'active bass' connection.  Linn Konfig was spun up on the laptop and the Exakt filters for the Super 20s were selected from the menu and installed into the Exaktbox whilst the power amps were still switched off. After confirming the Exaktbox connections against the Konfig diagram, it only took 15 minutes or so for everything to be ready to go. As is the way with active systems - care with connecting is critical.  Connect a bass channel to the tweeter and you can expect a short puff of smoke, silence and a bad smell.  So the bass driver is always connected first - if you accidentally send treble information to this driver its no big deal.  So make sure the bass drivers are connected then listen to music at low volume and make sure the bass driver is producing bass.  If its all good, then connect up the treble and listen to it very quietly to make sure its only handling treble.  If all is good, on with the music...

System

Here's the system driving the Super 20a with an Exakt feed, in source to speaker order:

  • 16 bit and 24 bit uncompressed FLAC files
  • QNAP 251 NAS with WD Red drives
  • Minimserver UPnP database
  • Cat 7 ethernet cable
  • Netgear GS-108T network switch with Friwo medical PSU
  • Chord Anthem streaming cable
  • Linn Akurate Exakt DSM streamer / Pre-amp (with power from PS Audio P5 regenerator)
  • Chord C-Stream streaming cable
  • Linn Akurate Exaktbox 10 DAC/processor (with power from PS Audio P5 regenerator)
  • Linn "silver" analogue interconnects
  • 2x Linn Akurate 4200/1 power amps (with power directly from the mains)
  • 2x 3m pairs of Naim SuperLumina speaker cables
  • All electronics supported by Cyrus Isoplats on Quadraspire EVO racks

 Tracks used:
  • Falling Out of Love - Mary Gauthier
  • Six Blade Knife (24 bit from DSD) - Dire Straits
  • Gula - Deadmau5
  • Keith Don't Go - Nils Lofgren
  • Fender Bender - Chris Jones
  • Breathe You In (ft. Laura Hahn) - Ficci
  • Wicked Game - London Grammar
  • Walking With Elephants - Ten Walls

First Impressions


Here you can see how fresh the Cherry veneer is on this pair - contrast with the Quadraspire cherry shelves.  Akurate Exakt DSM is on the far right hand rack, the Exaktbox 10 is on the middle shelf under the TV with the 2x 4-channel 4200/1 power amps on the lowest shelf
 
That brightness noted in R's home system was still in evidence here, making the system difficult to listen to, but bear with me as this isn't the end game here.  One thing we also noticed immediately was the articulation, drive and rhythm in the bass line - although there were some room modes being driven here, leading to a touch of boom - that initial stiffness noted at first listen in R's system isn't evident in the Exakt system - either due to the different system, some benefits of the 50 hours of playing time, or perhaps a combination of both. Vocals immediately stood out as crisp and clear with tone and intonation clear in the expression of the words.  So, some work to do.  I think it would've been good to leave them playing for a couple more days, but time was against us.

SPACE

Turning once again to Linn Konfig, the first thing to address was the room modes which were giving a touch of boom in the room - it wasn't at all excessive, but it was there.  Whilst the room measurements themselves were untouched, the position of the speakers in the room was amended to suit the positions of the Kudos boxes and the optimise button was pressed.  The newer SPACE implementation - where each left / right speaker receives different settings - was evident in the profile graph - much more so than with the PMC 26s.  This brought an immediate improvement to the punchiness, tunefulness and articulation of bass line.  But it was a touch light so we took a couple of dB out of the notch and narrowed it significantly and that worked a treat.  As usual with SPACE this opened out the mid-range and treble too - a mixed blessing.
Sometimes, its possible to tackle some vocal harshness by adding notches in space in the 65 to 74Hz range and whilst these gave some subtle benefit, it just wasn't significant.  So we moved up the range and added a -1.8 then -2.0dB treble shelf which Linn allows you to add from 8kHz upwards - and this was a little helpful, but not the answer.  So that was moved up to 17kHz and then we added a custom filter - a -2dB dip centred around 8.5kHz but with a very high width value which effectively gave us a 3.5kHz to 17kHz wide shelf. And that really hit the spot.  Notching this down to -3dB across the same frequency range got us to the right place.  Everything clicked at that point and we started to settle down into listening to the music rather than to the system and its tendancy to spotlight every single thing in the upper frequencies.  This is the first caveat - it would be great to get the speakers back again soon when they've had a lot more hours of use - to see if this treble attenuation can be dropped over time as the speakers break-in.

Listening to Music

So now we had a very satisfactory sounding system, we cracked on with listening to some tracks.  Bear in mind here that R has been listening to these speakers for around 3 years now and has been through a good few system upgrades during that time, so he's very familiar with their capabilities.  It turns out, whilst they might be familiar, they haven't really reached their full potential in the Naim passive system. What we heard in about 90 minutes of listening with Exakt was a revelation.  These speakers, whilst not carrying the same weight and authority as the PMCs (which have a somewhat larger visual and physical presence in the room), they're no longer out of their depth in my room.  They go astoundingly deep from such a small box, with plenty of drive and give a bass line that, had we not already heard the PMCs, would be thought of as very good indeed - add in their relatively small dimensions and that makes them quite remarkable in this area.  Tunes that needed to boogie along did so, attack is good as is the timing of the tune.
What about detail? Well, its astounding - these speakers really can resolve tiny tiny details that is beyond the capabilities of the PMCs and significantly beyond how they sound at home in the passive system. Both acoustic guitar tracks (Lofgren and Chris Jones) deliver string sounds that are crisp, clear and easy to pick out - delivering initial attack in spades and long long decays into the background. Spitty anger in Mary Gauthier's voice make you feel a bit uncomfortable and pleased that you're not the subject of her aggression. Vocals are superb - a good bit more texture, inflexion and intent than with the PMCs.  Imaging is spot on too - rock solid, easy to place, 3 dimensional and a little unsettling on those tracks (such as Ficci) that use processing to give a wrap-around effect in the room.
Is there a downside? Well, its difficult to find anything to fault but I would prefer a little more subtlety in treble leading edges - R found it just to his taste, for me its still a bit sharp.

But here's the thing - throughout, we could both follow tunes and feet were tapping - and I mean throughout. On top of that, R kept giving little involuntary smiles and shaking his head in disbelief.  These speakers are very much more capable than either of us really knew and Exakt with active amplification has brought that out from under the covers of passive operation.

I'll leave it with some of R's words - stunning, outstanding, and several more that I won't repeat in a public forum.

Post Script

We hope to get the speakers back again in a couple of weeks time to follow up on if they've settled in and need less treble attenuation - if this happens I'll report back here.  Also, after the Super 20s left the building, the SuperLumina speaker cable stayed in the house for a little longer.  Interestingly, using this cable on the treble of the PMCs reduced the gap in detail resolution by about 50%, bringing the PMCs closer to the Kudos boxes in this area.  Would I swap the PMCs for a pair of Super 20s? No, but that's no reflection on the capabilities of the Super 20a, more that there is a different set of priorities from which to choose.  Having lived with the superb bass performance of the PMCs, their relative lower level of detail resolution and lesser capabilities in vocal resolution are a reasonable compromise to live with.  And I'd be looking for a substantial improvement if moving on - not a different compromise.  Roll-on the Kudos T-606 in the summer! 


Thanks to Kudos and Acoustica for the loan of the speakers.