"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

Thursday 19 November 2015

Listening In A Meadow? Exaktly.

I quite like pizza.  And red wine.  Generally, these are consumed indoors – either at home, or in a restaurant.  Occasionally (it would be summertime), it might be on a terrace overlooking the Med, or perched on a stool outside a tent.  It’s not normal to be consuming these treats in a field, but that might’ve been what was happening the other night, accompanied by Dire Straits playing in the background on a pair of Linn Exakt 350s. Maybe I just have an over-fertile imagination.  It’s strange though, as in reality, we seemed to be sat in a large top-floor room which was as real as the pizzas, and the red wine.

What is this opening ramble?  What does it mean? Was the wine too strong?  Were there too many glasses consumed?  Let’s start back at the beginning and work through to what that opening paragraph is all about.  Maybe.

Cards on the table.  I’ve heard lots of Linn 350 speakers.  And Linn Exakt systems.  Some were combined together.  I tend to like Exakt systems, when they’ve been set up properly (not a given), but tend not to like 350s.  When I’ve heard them both together, they’ve been in inappropriate locations, like a massive double storey hard surfaced furniture shop (not a great approach to showing off your systems Linn), or in the factory in a ballroom with 200 people, etc.  So Exakt and 350s have not been a great experience so far, but then they’ve not had much of a chance either, with the best I've heard them being in the main dem room at HoL - my preference still being for the Akubariks or Komris.

One of the more enjoyable systems featuring 350s belong to Linn Forum member (let’s call him “A”) and uses a Renew DS/0, Akurate Kontrol/0 and a non-Dynamik Twin.  That system still features their special feature – a slightly “disconnected” bass.  A and I meet up from time to time with music and hifi always the excuse – be it at shows, dealer demos or in the listening room.  A lives down South, I don’t.  So we get together when it makes sense.  Through A, I met P, also a forum member and living down South, and we tend to meet up at either of their houses when there’s a good excuse to listen to some music, or compare the effects of software changes and other bits n pieces of new kit.

The 2 guys down South have recently added another member into this happily sceptical band of middle aged music listening blokes.  For simplicity, this new bloke, also a forum contributor, will be called N.  This week was the first time I’ve had a chance to join in, with another trip to London being necessary for work purposes.  Logistics sorted, pizza orders confirmed for the 3rd time (sorry P) and all was set for a bit of Exakt 350 listening.  It even all went to plan.  Decent pizzas, great red wine and we settled into the listening room to munch over the background Dire Straits.

And what a listening room.  Perched on the top (2nd floor) of a substantial place, approx. 6m by 4m and with a sloping wall / ceiling down one long side as it tucks under the roofline.  A pair of rather tasty looking Linn Exakt integrated 350s in piano black stand guard either side of powered grey screen on one of the shorter walls, with a TAG MacLaren centre speaker stood on a pedestal stand.  A venerable Linn Melodik and associated Exaktbox sub are in one front corner. That’s all you see from the listening seat – side / rear speakers are multi-driver MK units flush fitted into the side walls.  There’s a large L-shaped sofa for 5 or 6 and a vast footstool big enough for all.  This is a very comfortable place to settle into for tunes and movies.  Across the back wall there are 2 built-in cupboards.  One houses the very large SIM2 projector (watching movies with all the lights on is no problem), the other the equipment rack.

Piano Black Linn 350 Exakt.  Tasty. And old skool Linn Melodik sub

And what a rack this is.  Much of what’s in there will be on the wish list of many an audiophile / music lover.  Perched on traditional Quadraspire are (from top to bottom): an SME 30 turntable equipped with series V arm and Koetsu Red; Linn Klimax Exakt DSM; Tom Evans Audio Design phono stage, Anthem processor and multi-channel TAG MacLaren power amp (for centre and rears).  Music is normally held on a 4 bay QNAP NAS, but with some currently stored on a Melco N1A and some on a Melco N1Z whilst the resident A is being compared to a demo Z.  All connectivity to the main stereo system is with standard Cat 5 ethernet cables.  Exakt links included, with one cable from the KEDSM to each speaker and the sub daisy-chained from the right hand 350.

Main Quadraspire Rack,  Untidy Cables Due to Experimenting with NAS Storage (see later pic below)
SME 30 / Series V / Koetsu Red

It’s gonna be good, right?  

The 350s are stood very close to the front wall, to enable them to be positioned either side of the off-centre screen (off-centre due to the sloping ceiling).  This is possible due to Linn’s SPACE Optimisation+ feature.  During set up, the room is measured, the speakers are manoeuvred until they’re at the point they sound best in the room (the ‘ideal’ position measurement), then their position is also measured.  The speakers are then moved to their practical position and measured in this position, relative to nearby walls.  All this data is then entered into Linn’s Konfig software, algorithms are crunched and the signals sent to each speaker allow for their compromised position in the room.  I’ve heard this demo’d a few times and its very impressive.  It doesn’t perfectly recreate the sound generated in the “ideal” position, but its very close, considering what it allows in terms of much more physically discrete speaker locations.

What about the sub?  Well Linn have just added subwoofers to their Exakt system with the Exaktbox Sub which is designed to take the Exakt signal to a sub with built-in power amps.  N had just hefted the sub into the room a couple of days before (his and his mate’s back are probably still recovering – its not exactly lightweight), and it hadn’t been set up.  We had it powered up to start with, but then chose to shut it down and come back to it later.
Pizzas done, music was loaded up into a playlist on the iPad Mini (or the iPad, or the Macbook!) and we got on with some listening.  It was very quickly clear that there’s only one sweet spot in the room – the intended listening seat.  Being elsewhere in the room was a real compromise – even just one seat to the right of the hotspot.  Not to worry, that’s not at all unusual.  We listened to some classical organ music (vague, sorry about that, it’s not something I know much about), some Clapton on video and some Seal.  We settle into focused listening with something we’re all very familiar with – Daft Punk’s Georgio Moroder from the Random Access Memories album.  It has an interesting opening with a narrative by Georgio, underpinned by background chatter and some bass meanderings.  Then of course it kicks in with some driving bass lines and electronic tuneage.  It’s very good for understanding system resolution and tunefulness.  Tune dem anyone?  We don’t discuss that, as everyone has their own way of listening for what they like, but we all do try to figure out if we’re just enjoying the flow of the music and if it’s causing foot tapping or not.

It was difficult to establish what’s going on away from the hot seat, so we take turns to try it out.  For me the sound was OK, but not overwhelming.  I suppose I was expecting something special, and to hear that from the off.  We mess about a bit more with some more material – including a great scene in the film Fifth Element.  I’d forgotten just how quirky and amusing that film is – must get around to watching it again sometime very soon.  Having got used to the sound, we start thinking about tweaking a few things and start with the QNAP and Melco options.  Various combinations were tried – each Melco on its own, then with the QNAP fed through one of them.  I think I heard some small differences, with a very slight preference for the N1A Melco, but there was nothing there that was making the system sing, nor were any changes (real or imagined) very significant.  Another aspect was a serious lack of imaging – there was no single point for the singer’s voice and London Grammar’s album just didn’t shimmer and fill the space in the room.

To the left, QNAP NAS main storage and a couple of Melco NAS boxes, the N1A being resident, the N1Z being a demo unit

I think it was P who finally bit the bullet and we cranked up Konfig on the Macbook.  We switched SPACE Optimisation on and off a few times, but I really couldn’t hear it making any real difference.  Strange, it’s normally very obvious.  We checked the SPACE filter graph and found a straight line.  Those familiar with looking at what SPACE does, will know that this is unusual.  Essentially, the software calculates where the room is likely to give bass humps (due to the dimensions of the room) and then feeds a signal to the system that has very narrow, often quite deep, notched attenuation filters – the idea being that the deep notches in the signal cancel out the humps created by the room.  Most rooms have 2 to 4 nodes.  Yet here we have a completely flat profile.  And a room map with no speakers or furniture identified.  Now, there have been some recent software updates that have had odd effects in Konfig, such as completely shutting down one speaker, forgetting which speaker models are in use etc., all fixable by restarting the software and the system, although forgetting the speaker model did actually need the model to be re-input.  So maybe a software bug has caused the problem, but it’s not really possible to track down what’s happened here.  The cause of the lack of filtering was soon obvious and I hope it’s been down to an error somewhere along the line as N clarified that there had been notches on the graph previously.  Perhaps a software or hardware change had caused the problem.  One for owners to check back on from time to time (rather like I discovered that my speaker model had been dropped from the standard SPACE config in my own system – noticed one day after a software upgrade seemed to have degraded the sound a bit).

Anyway, thinking back to some stuff I’ve read on the Linn forum, the problem was soon identified.  The room dimensions are supposed to be entered into Konfig in metres.  Here they had been entered in cms.  So a 6.3m long room becomes a 630m long room, as far as the calculations are concerned.  And when that room is also recorded as being 410m wide and 255m high, the speakers imagine they are living in a field.  And when a set of speakers live in a field, they don’t create any bass humps as their field is too big to have bass humps.  So SPACE sets a correctly flat profile.  Except we weren’t in a field, we were definitely in a room.  The measurements were quickly corrected to metres, and we entered a rough position for the subwoofer.  But when we did this by roughly guessing its distance from the room boundaries, the Konfig diagram showed the subwoofer was half outside the room. Hmmm.  Something not right there.  A quick run of the optimisation software delivered 4 notches and we were clearly starting to head in the right direction.

N quickly dug out the laser measure and we got to work stepping through Konfig’s measurement requirements.  Even when converted from cms to metres, some of the dimensions were out – the room width was recorded as 4.1m, but turned out to be 3.66m – an error of 0.5m is quite significant.  About 15 minutes of measuring, checking and entering the data and we had a new optimisation ready, with 3 notched filters – the lowest frequency notched to about -29dB with the other 2 much further up the frequency range and much shallower.  Due to time restrictions, we just converted the speaker’s “ideal” location from the cms already in the system.  With much more time it would be worth revisiting the ideal position data too, but that involves removing speaker spikes and shuffling the speakers about in the room – there wasn’t time this evening.

Daft Punk went back on, Leonard Cohen, Seal and some London Grammar.  Some listening, some small tweaks on the depth of the optimisation notches.  We dial in a +1.5dB treble shelf to compensate for the heavy soft furnishings between speakers and listening position.  I think we ended up with the notches back to the SPACE recommended settings in the end – quite unusual.  This was quite some improvement.  Bass lines are now tuneful, and there’s real imaging going on – still a little shallow front to back (possibly an effect of being so close to the front wall of the room), but very wide left to right and instruments and voices easily pinpointed as individual parts of the whole.  The opening to the Georgio track had a stable, central voice, the background noise was recognisable as chatter and the quiet underlying bass line is playing a clearly distinguishable tune. Excellent.  What a difference a few measurements can make (although, to be fair, changing from cms to metres isn’t exactly a subtle tweak).  Next we mess about with some cables and the system really starts to sing.  Now, we’re listening to the best pair of 350s I’ve heard.  The bass lines are even in time with the rest of the music, which is not a 350 forte – Exakt must be doing its stuff, and perhaps the latest 4th order bass roll-off changes have been really fundamental to getting the best from the 350s.  This system is now really enjoyable – something quite special, given my previous challenge with enjoying 350s.  Sitting position in the room is now much less critical, although still best from the hot seat of course.
N then played Porgy and Bess Summertime, Procol Harum performing A Whiter Shade of Pale with the Danish National Concert Orchestra, Eva Cassidy Fields of Gold and some of his other favourites (he has a very extensive and eclectic music collection) which all sounded very engaging.

There’s probably more to come.  Given that we have relied here upon the “ideal” speaker positions that were existing in Konfig (but converted to metres), there’s probably scope to go right back to the beginning and determine the “ideal” speaker position again.  If that’s not right then the SPACE Optimization+ facility for positioning the speaker into the practical position will be based on some incorrect calculations.  If that is the case, then this system really could move on from excellent to truly stunning.  That’s the work of at least half a day.

Now I’m hoping to get back again soon (probably in early 2016) to spend the evening listening to music, to give that SME a good listen and to put that fantastic screen and projector to good use. Hopefully, over the next few days and weeks, N can enjoy settling into some serious music listening too.  Thanks for your hospitality N, a very enjoyable evening.

(with thanks to P for a contribution on the tracks played and correction of some of the details).