An Edifying Journey ...

[fas42]

Continuing to do fine tuning of the mains filtering - unfortunately, still showing sensitivity to what's happening on the neighbouring socket; and realised that some further benefit could be possible by more dressing of cables.

 

What's the progress? A bit more detail, which is accompanied by a touch of harshness unless absolutely everything is in its best state - the presentation from a single speaker is mighty close to being invisible at peak behaviour; but still betrays itself when very close to the drivers ... I don't know yet whether this will be resolved by improving the isolation of the player and speakers from electrical noise, or only be making changes to the actual components themselves, or doing something to the optical link between the two ... To Be Determined, 😉.

 

A CD which is extremely useful right now is a collection of original Glen Miller recordings, 1939 - 1942 - getting the bite of the brass choruses to not exhibit any edginess is showing the way; the slightest wrong move introduces major unpleasantness ...

[fas42]

Interesting ... continuing the efforts to understand how to improve, and optimise the mains filtering bits and pieces, the latest new bit of data is that changing the position of a decoupling item within the mains cable going to the TV, etc, stuff, which is plugged into an adjacent socket (!!!), made a major change to the sound - it was only moved from one end to the other; why should it have had such an effect?

 

At least two possible reasons: there could have been a RF resonance which went away when the distances altered; or it was filtering some contact noise of the plug and socket at that end. The point is, that electrical noise is notoriously obstinate in wanting to raise its ugly head, and it can take much effort to tame it, or to make the audio circuitry impervious to its presence.

 

Symptoms? That Schubert quartet CD which is right on the edge of SQ pleasantness, yields decent violin tone, or, goes scratchy - the latter is impossible to put up with; there is absolutely nothing subtle about the audibility of the interference.

[fas42]

But ... even that last tweak is not enough, ... a couple of days running confirmed the general uplift, as per the last post - could it be improved ... Yes!! Disconnecting the neighbouring mains plug feeding the other entertainment gear allowed the SQ to very significantly improve - bugger!! Because, it means the decoupling from electrical noise is still not effective enough, necessitating further investigation ... .

 

The good news - there has to be good news, yes? - is that peak performance is now very nice ... easily fills the whole house with the strains of 30's and 40's recordings, lacking any disturbing qualities to the experience. This is what is lost when, say, I add some interference that can impact, by say plugging the TV, etc, back in.

[fas42]

Tested whether the interference was due to the length, and path of the main cable, or because of the proximity of the TV stuff, their internal circuits, to the audio gear - easily done by powering the entertainment components using another(!) extension cord, to a different circuit in the house. This confirmed it was noise coming through that cable - the extra distancing made the issue essentially vanish.

 

So, decided to add quite a bit more distancing to the DVD players power feed - this was the shortest; would it be the main beneficiary? And, yes, it was! In fact, it caused quite a radical change to the sound, on first listen ... why? Firstly, it was adding more isolation; and secondly, quite a bit of cable was disturbed in the adding, meaning a significant lot of static noise was added into the bargain.

 

This was so strong that Bev was very disturbed  ... "it sounds too powerful!", "it's hurting my ears!" - in conventional audio jargon, the sound had become quite forward in nature. She went to the other part of the house, and didn't want to be aware of it ...

 

But I wasn't fussed ... there were very positive signs - depth and detail had picked up, more than making up for the more forceful presentation ... anyone who takes this sort of thing seriously knows that a change needs to "bed in", as the materials relax into their new positioning, and static noise behaviours settle down.

 

And so it has proven ... steadily improving as I write; becoming, "more comfortable" ... .

[fas42]

Next day ... interesting ...

 

First CD, the same as that Bev reacted to, strongly, negatively - to my ears very little had changed, from yesterday, for this album ... lots of detail, but very forward. Which says, to me, that the "bedding in", so far, has been minor - at the moment I feel that the balance from a cold start has shifted from the more comfortable, to one which is more 'aggressive'. But this is not a bad thing, if the status of a full warmed up rig has greater integrity than before this last, addition of mains lead, tweak.

 

Definite are the gains in the presentation throwing up another reality, that of the recording space - the window into that is less blurred; the focus is sharper.

 

One marker is very close to being fully realised - a true mono track aligns to your position with respect to the speakers; if you are slightly left of the the right hand speaker, then that slightly left position is the precise centre of the soundstage you perceive.

[fas42]

A little update ... the gains have sustained, but the peak quality is still fragile. At its best, currently, true invisibility of a speaker on one side, standing close to and directly in front of it, is within reach - but this is easily lost. A key reason is that the setup is very messy, of the nature of a prototype - as I have mentioned many times - and the integrity of some aspect is disturbed far too easily. Consolidating and stabilising the physical arrangement would make this go away; but then I lose the ability to easily modify what's there, to test how changes alter things - it's a tricky path to navigate; but I want to persist until I'm certain I have very close to an optimum.

 

The good news appears to be that I may get away with not touching the internals of the speakers any more ... yes, the performance could undoubtedly improve if mods are done there; but the idea is to see if the raw capabilities of the units are up to delivering competent sound, if the tweaking is almost completely kept external to them.

[fas42]

Okay, another status update. Turned out that the dressing of power cord plugged into the adjoining socket, that feeds the TV, etc, could be improved - was picking up too much noise close to the wall socket. Just minor reorganising of that made some degradation go away; unplugging that particular cord demonstrated, before doing the adjusting, that the impact was audible.

 

Very pleased with where the setup is now. Speakers are say, 98% invisible, close to and directly in front on one side. Sounds very good from a dead cold start; it's in the region where "there's no such thing as a bad recording!" , old recordings throw up huge acoustics with no trouble.

 

What could be better? Well, it's still audible that the treble could be better as the components warm up, still takes about 3 CDs worth for that to fully stabilise; the sideways tracking of the soundstage of a true mono recording to go, say, well left of the left speaker needs to be better. And, the isolation of the rig from noise on the mains is still not good enough, as I mentioned at the start of this post.

 

Should be mentioned ... this latest combo uses technologies mighty far apart from the previous rig; the NAD duo used a CD player, with linear PS, fed the analogue signal into a variation of class AB amplifier with linear PS, that drove cheap, passive speakers. By contrast, the Edifiers pick up an optical digital signal from a DVD player which uses a switching PS, and are active speakers which do the D/A internally, and amplify using class D amps, all fed by a switching PS. Yet, the same CD essentially "sounds the same" between the two, now - the 'vibe' is identical ... and how could it be anything else, if they have any claims to being accurate ... .

[fas42]

Good, another bit o' progress! Now, I haven't ever used Ethernet in any area associated with audio, which means, say, no streaming ... but, I have the TV between these speakers linked up, via a pretty long cable. And the cable snakes its way through the, old, house - largely hidden, but not especially prettied up, to suit a show home arrangement, .

 

I was suspicious of this cable, which motivated me in part to do the adjustment mentioned in the start of the previous post - and that helped, as stated. Okay, let's pull the sending end of this cable from the network box ... yep, did the trick; big uptick in quality. So, where was the interference coming in, still? Looking around, the mains feed to the amplifier, before all the heavy duty filtering crossed the path at a single point, at right angles, of the Ethernet run by about 10" or so, - surely that was enough? Ummm, no! Increased the spacing to a number feet - and, yes, that made all the difference ... lesson learnt ...

 

Now I can understand why people fuss about Ethernet issues - the noise generated by the constant electrical muttering on these links is easily picked up through proximity, if nothing else - and sucks some of the life out of the SQ.

 

Easily tested ... just shut down the networking in your house completely; pull the power leads of everything related to such from the wall - and see if it makes a difference. If it does, then you now have another fun area to try tweaking ideas ... .

[fas42]

A CD which I used a lot with the NAD combo shines well, on these speakers ...

 

 

[fas42]

Also, first time I tried this recording,

 

 

Has no trouble doing full justice to these tracks, the raw impact is conveyed at realistic volumes, with ease ...

 

 

[fas42]

Comfortable enough now with the setup's peak performance to try some simple tests to see if some of the tweaking, especially the expensive stuff, is not actually necessary, any more; that is, the attenuation of noise is done adequately by other filtering mods, and hence the pricey parts can be discarded without a SQ loss.

 

First up, the DIY isolating transformer used for the Edifiers feed; which has filtering parts in the assembly - can it go? Ummm, looks like, No - bypassing that part of the filtering chain appeared initially not to be so problematic; but the longer I listened, the more the removal was apparent - a flatness, a boring quality was more and more audible. Reinserting that filtering link immediately restored the life and sparkle - yes, currently, it is necessary ...

 

There is always the possibility that beefing up other parts of the filtering arrangement may still do the job; using cheaper parts which are just as effective. But this requires lots of experimentation - all takes time, and motivation, to try things . On the ToDo list ...

 

The joke is that such an isolating piece of kit, in a proper box, all tizzied up, would cost nearly half of what the the actual pair of speakers were to buy; and that's for me buying the best value for money items to do the job. Which is part of the craziness of this industry ... the extra bits and pieces needed to get the last, and essential 10% of the quality are easily as much again in cost as the stuff that does 99% of the work ... something to think about, .

[fas42]

Tried shortening the run of extension lead to the DVD player; removing a section that was the first tried, in case it was the specific nature of the lead used that made a difference ... another, No! SQ was definitely less; and was now allowing detectable interference from the TV gear to pass through - as part of this, decided to reorganise how some parts of the filtering were distanced from each other, to improve any possible cross-interference. Reinserted the removed section; and the prior SQ was back again, and if anything was a notch of two better than before the removal, it seemed - was this because of the spacing refinement, or something else? The setup is messy, and there are so many factors at work - it can be very hard to determine precisely which is "The Weakest Link!"; and at this level of optimising the slightest variation in how things are done can mean a lot; the hard work is nailing exactly which area is the dominating bottleneck.

 

Transparency, , is very, very good - the 'dreariest' recordings show tons of detail and depth, and are highly satisfying ...

[fas42]

The prototype nature of the filters came back to bite me ... the SQ was not quite right today, and was getting worse; and it took a bit to work out what was going on: in the exercise of the previous post there was a bit of jiggling of the input lead of one of the filters; how it was mounted loosened, and it started to twist; ultimately a connection inside the filter came adrift, and the DVD player lost power. Which made me realise what was going on: the loss of integrity of the securing of the input lead was enough to introduce noise, from the cable being able to move, ever so slightly, with respect to the platform and parts of the filter. I then did a better job of locking that bit of lead more securely, and it showed a solid improvement; the tracks earlier in the day which weren't convincing came good.

 

Which yet again demonstrates the importance of checking and rechecking everything when changes are made - it is so easy to disturb something which is critical, when trying variations to determine what matters, in setups which are experimental. Unfortunately, this means it takes time to properly evaluate - is it sounding, say, worse now because of my last intentional moves - or is it because I accidentally lost some integrity elsewhere, because of clumsiness or narrowness of focus?

[fas42]

The rig at the moment keeps surprising, and delighting me - switched it on this morning, from cold, and tried a compilation CD of The Who - the very early songs are a solid test; they can sound edgy, and very raw. But not today ... threw out a solid acoustic, nice depth, good drums; a solid 👍 ...

 

 

[fas42]

Huge acoustics, and bite on this album - brilliant to listen to,

 

 

[fas42]

Right, I was hoping that the umbilical connection from the right speaker to the left had a high enough integrity - it uses DIN type connectors - to do the job. But it appears not - wriggling them around enough to refresh the metal to metal contact brought the SQ up - making the slow onset of a 'flatness' to what I was hearing vanish.

 

Which means that I will have to address this. I will very carefully examine the nature of the connectors and how they mate; and see whether some contact surface treatment might work. If that doesn't work out, then the next step will be to discard the connectors, and hard-wire through. Which I very much prefer not to do ...

[fas42]

First look ... the plug and socket are good quality; plenty of metal on the socket pins to make contact with the plug pins. Which means that enhancing the contact quality between the two is worth trying. The other thing, because of the nature of the DIN design itself, is that the plug is not held rigid by the socket part; it can wobble sideways when one puts some pressure on the plug in that direction. Which is never a good thing with any connector, when used in audio; free movement means various mechanisms can easily generate noise, and that is something that needs to be minimised. So, either lock the parts into a solid, 'cemented' relationship; or add damping. The latter I had already added, but not in a fully considered way.

 

So, will carefully insert damping material into the heart of the connectors, and add contact enhancing to the contact areas - as a first try. Will this be good enough to achieve adequate integrity? I don't know, and so that will be the first round of experimenting; if it turns out not to eliminate issues at this link in the chain, then I will need to explore further - ultimately, soldering the cables directly to the interior parts will be resorted to, if it makes sense to do so ...

 

 

[fas42]

Decided to just try damping the connection area first - for one end of the cable only. Because of the fiddling it took a day or two for the sound to stabilise; and at this point I could again hear the loss of SQ after some time starting from cold. Then wriggling the connector at the untouched end restored the quality - which indicated that the improved damping at the treated end was doing its job ... otherwise, I would have needed to reseat that end as well, to get the improvement.

 

So, today I added the damping at the untreated end - wasn't happy with how well I did it, so might have to redo the application if it shows signs of not being optimum - will leave it for a day or so before making a judgement.

[fas42]

Well, I ended up unhappy, ... yesterday it showed up a symptom I hate: the SQ "goes off", and the only way to resolve it is by resetting the rig; that is, powering down, letting power supplies fully discharge, and then switching on again - this is a sign that some mechanism is causing a voltage to build up, somewhere, which doesn't dissipate with ongoing use; which upsets the normal functioning. Only having all voltage rails go to zero, throughout, gets operations back to normal ...

 

Not certain whether the less than optimum damping on the other end connection was the cause; anyway, redid the 'treatment', taking more care - and will see how it goes today, .

[fas42]

Hmmm ... symptoms repeated themselves - tried resetting just the DVD player, and that was inconclusive; the SQ did pick up again, but not enough to be convincing.

 

There is a problem when trying to diagnose system ailments - you concentrate on one aspect, trying to find the correct or optimum arrangement; but while you are doing this, over some days, another part of the system loses some of its integrity for completely unrelated reasons. If you don't realise this, all the experimenting you have just done is largely useless - because the SQ has been altering over this same time, from this separate, not known issue. And I have been caught by this a few times over the years.

 

Have I got this situation now? Before more fiddling with the umbilical connections I going to 'refresh' the connections on the filtering assemblies, to see if that is where I'm getting this behaviour - IME it only needs a tiny bit of electrical noise coming in, more than is acceptable, to start building up a SQ damaging unbalance somewhere; if this can be kept below needing resetting over 24 hours I can live with that .

[fas42]

And, what I said in the last post came to be ... what had happened is that I adjusted the supporting damping of the umbilical cable, thinking I had improved it; done at the same time as adding damping to the end connection. Well, this had sagged, and the cable was at the point of touching a hard surface ...

 

Easy to fix - just put damping at the point where it was too close for comfort - and the SQ jumped right back up, to a solid, peak level .

 

Lesson? Cables are important. Very important. Very, very important. Very, very, VERY important. And not because they're a simple combination of R, L and C, so beloved by those of an objectivist stance; but rather because the materials in their construction have parasitic electrical behaviours, which need to be kept under control. Ignore this, and it's highly likely the full potential of the playback chain will never be realised.

[fas42]

Bold move now, ... what happened yesterday demonstrated the importance of getting that umbilical cord just right, and less than pristine replay of a particular CD provoked me into making a Big Change. Well, not really - what I had on the ToDo list, for a long time, was to improve the physical stability of that cable; by changing how it was routed between the right and left speaker - the original path hadn't been touched from way back in the beginning ... could it be improved?

 

Indeed it could - currently it was "attached" to various surfaces which weren't the most solid, or steady. So, biting the bullet, I completely reworked the path, having it now only contacting very stable surfaces. And, at least some of you can guess what's coming, .

 

Yes, the SQ dropped down quite considerably ... what the? Ummm, to be expected - I had to unbend and make new bends on the cable to get the new postioning done; what I had effectively done was to undo all the 'burning in' of the cable materials; the plastics were now stressed again, and the strands of the copper wiring had slightly shifted against each other, breaking down poor internal contacts; which changed how the currents flowed in the overall conductor. It's now a waiting game, seeing how long it takes for all the disturbed physical equilibrium to again settle down ... hopefully at that time the overall SQ is up a notch or two - shall see ...

 

What were the losses? Well, now back into the world of "good" and "bad" recordings; that is, recordings which critically require all low level detail to be accurately presented have lost the necessary integrity in the replay; they are gritty, clogged, far poorer soundstage - sort of like normal hifi sound, now .

[fas42]

And indeed it turned out to be a 'bold' move, !

 

Next day, any turnaround? ... Naaahh!! I said to Bev, this is sounding bloody 'orrible!! She just looked at me, and nodded her head in vigorous agreement ... .

 

So, start a countdown now for how many days it takes for that damn cable to settle down ... which it hopefully will. And this, boys and girls, is why you can't just take a system which is running nicely to somewhere else, in order to demonstrate a point; you're almost guaranteed to disturb some critical equilibrium - and, it will sound like shite - and, you will have lots of egg on your face, . So, welcome to the bizarro world of achieving consistently competent audio replay ...

 

Solution? Ditch the current umbilical cord, and build one which can be physically manipulated, with absolutely minimal consequences - this is not a trivial exercise; and makes the cost of the tweaking go ever higher, for a high value for money setup. Will I do this? Perhaps, will see how long it takes for the manufacturer's cable to stabilise again ...

 

Edit: Just in case anyone is not clear on what that "bold move" actually was, absolutely nothing was changed elsewhere, no cables were unplugged and replugged - and that means, especially the umbilical cable. The end connections remained locked solidly in place the whole time, and merely the bundle of conductors inside the cable proper were jiggled a great deal, as I pushed and pulled on various parts of the outside insulation ...

[fas42]

Well, some good news! Yesterday, after a pretty awful start, as noted in previous post, it steadily settled down, over the day. Today, first thing, put on the very same CD that sounded bloody off; and, big improvement! Not yet as good as the setup can sound first thing, but highly acceptable.

 

Which says what? That the cable has taken less than two days to reach a decent physical equilibrium, after being heavily manipulated, with a new set of bends in place. I can live with that; but it shows how important it is to take such changes in a more ambitious rig seriously. The alternative is to replace less than optimal cable constructions with ones that can take major stressing of the materials in their stride, by not increasing the electrical noise substantially as they conform and relax into their new arrangement.

[fas42]

Interesting one today ... Bev said, it sounds worse! But, to me I was hearing more detail, at the cold start - we were both right; and it says that the cable needs more settling down time ...

 

As the cable becomes less a major contributor to being audible, it goes through a phase of enabling the ear to unravel more detail, but that detail is still mixed with too much distortion - hence plenty to hear, but accompanied by an unpleasant edge. People have often noted this progression with audio updates - starts off sounding reasonable, then goes through a phase of being pretty unpleasant; and, finally, rounds out ... this is a natural progression, of the materials fully stabilising, in their new situation.

 

Should mean that tomorrow it will have similar detail as today, but be more relaxed in the presentation - shall see!