Tuesday 3 May 2016

"Historic" recordings of now defunct Philips HT system

Just to mention that there are now 3 recordings of a Philips Home Theatre in a box, that I used as a test bed for a number of years, on my YouTube channel, https://www.youtube.com/channel/UCzkx85ez3DVxRAnpkbQEA2w. These recordings are over 2 years old, made on a very limited quality Fuji camera, noisy and highly prone to having the recording circuit overloading - but they give some idea of how that system performed.

There's a solo blues guitar effort, some choral work, and just today added a pipe organ piece, https://www.youtube.com/watch?v=iZ9LQh3UbWU - the latter I was motivated to do because there was discussion in an audio forum about such instruments, which I believe should convey majesty and richness in the sound, irrespective of the bass response of the playback system.

Friday 18 March 2016

What do YouTube videos show us? - Part 1

'Bout time I added some more stuff to this place, so here goes!!

I have surfed YouTube audio system videos over the years, largely to get a sense of how the sound would have come across if I were in that particular, recorded space in person. People might dispute that this is possible, because, "YouTube is compressed crap!!", but I find that it's relatively easy to separate the good'uns from the bad'uns. One of the spots I revisit is Peter Breuniger's AVshowreports channel, because he uses a standard recording technique, making comparisons between various sound environments very straightforward.

Just visited his latest clip, https://www.youtube.com/watch?v=WHrXQ8L_IDI, and that inspired this post - unfortunately, in a very negative sense - sorry, Peter!!

This, is exactly what gives audio reproduction a bad name - a very brash, in your face, distorted, "hifi" sound - so many things wrong with it; impossible to live with. Yet, the video is about how to manipulate what's happening in the bass frequencies, so as to "fix" the sound - sorry, boys and girls, ain't gonna happen! Any variation of the bass behaviour will not do one iota of good in resolving the poor quality of what's occurring above those frequencies - a completely different strategy is required to extract competent sound from this setup.

So, this clip is an excellent example of what NOT to do to improve playback quality - unless, of course, one just wants to achieve variations of the typical hifi sound ... which is miles from conjuring an illusion of "real" music ...



Tuesday 23 February 2016

Some history of where I've been so far ...

For a bit of fun, I've uploaded a clip of what I was getting some 3 years ago or so - this was from a well made Philips Home Theatre all-in-one system - internal quality about that of NAD units - which was discarded by a member of the family. Unfortunately, my recording setup was very primitive, a Fuji camera with poor signal to noise ratio, bad automatic gain control that overloaded far too easily - I tried to get a flavour on how the system sounded many times, but the recording was usually unsatisfactory.

Anyway, I just went through listening again to some of those attempts, which make sense to my ears - here is one that conveys the ability of that configuration to project a "full" soundstage, from well outside the playback room: https://www.youtube.com/watch?v=b3b9bk2Gj6o ... https://www.youtube.com/watch?v=7yhR_fYQbbg (clip was tidied up a bit ...)

Update: for those not into classical, here's a grab of a bit of blues guitar playing through that system during the same period: https://www.youtube.com/watch?v=6MSE90cOni4 - where the recorder was in the same room. I had major problems minimising any overloading of the mic and recording mechanism, always - getting a balance between that and noise was hard.

Friday 19 February 2016

It appears a corner has been turned ...

For years I have been waiting for CD, digital replay mechanisms to be "robust" enough to deliver competent sound, continuously, in raw form. Waiting ... and waiting ... and waiting - 30 years worth of waiting!! There were many false excitements along the way, reports of "magical" new components that had it all ... but the really-hard-to-please crowd would knock them on the head in that somewhat contemptuous way, "very good for digital, but not in the analogue class of performance!".

Yesterday, I came across some personal experiences of diehard vinyl lovers who have heard some of the latest, best, most expensive digital source units - and who are converted. Finally, the top end of the development crowd have worked out enough tricks to get the engineering good enough for so that any limitations, weaknesses elsewhere in the replay system are not accentuated or triggered - and the normal consumer can buy these units, plug them in, and get satisfying sound.

Of course, these components are absurdly expensive, to the man on the street - this is Bentley territory. The old story of how man progresses - first the premium level toys are created for those well off, who are willing to pay silly money to get results - and then the trickle down process starts. It seems that it doesn't really work any other way in some fields ... a grotesquely over-engineered version has to be created, and sold in small quantities, as a proof of concept exercise; then, the engineering types begin to work out what the really crucial aspects of this battleship construction are, to get the results that actually matter - and steadily far more efficient, in terms of materials used, versions are devised ... value for money returns to the equation.

The other method of achieving high quality sound from CD recordings has always been available - that which I use, locating the various weaknesses in the overall system which are the most damaging to getting decent digital sound, and countering them, one by one. Luckily, this is highly effective - and far, far cheaper!! The end results are very similar - ultimately, convincing sound, the conjuring of a rock solid auditory illusion can be made to happen ...


Wednesday 17 February 2016

Audio Conjuring don't come easy! - A Case Study: the Kii Audio Three

This audio replay component is an interesting example of the dilemma the industry is in at the moment. It's an active speaker system, which includes the capability of digital input - meaning, that all is needed for reproduction to occur is to feed the right input with material from any capable source, a very cheap storage device that can output digital audio would be sufficient; it has been designed and developed by a highly capable audio circuitry design engineer, Bruno Putzeys, he has an excellent reputation for conceiving and bringing into existence fresh approaches to elements of the audio reproduction chain, high levels of praise have been bestowed upon products originating from him, both people coming from a technical viewpoint and those only interested in "what it sounds like" are impressed by his efforts ... but, this new product, under the banner Kii, has been getting very mixed reports - everything from "dreadful to listen to", to "can't imagine it being better!!"... so, what's going on ??

Particular of note is that very negative reports have been garnered from its presence at major audio shows in the USA, the two most recent being RMAF and CES. People who are familiar with decent audio sound are completely unimpressed, indeed found its sound quite offputting - at CES 2016 nearly every well known reviewer completely ignored it in their summaries. Why??

Luckily, a means of hearing what it sounded like at CES 2016, at least at one point of time, is available: https://www.youtube.com/watch?v=XZt6DokXi1s, a video report by AVshowreports on YouTube. This includes a long segment at the end of the clip of the speakers in operation - and, it is relatively easy, even on a YouTube video(!), to hear that the sound is deficient - it has a "shouty", uncomfortable quality to it, which seems to get worse as the clip progresses ... what is happening?

And ... just read a post on What's Best Forum: http://www.whatsbestforum.com/showthread.php?18437-Kii-Three-speaker-review-english-version&p=379168&viewfull=1#post379168. These are the impressions by a buyer of the units, who will use them to analyse recording mixes ... and his comments are extremely familiar: the quality is close, very, oh so very close to being "there" - yet, there is something not quite right ...

To me, these are the classic symptoms of digitally based replay which has the potential of producing superb sound ... when it is in the "zone" the result is music which is immensely satisfying to experience, but, the slightest weakness in the integrity of the complete chain can easily cause a quality which is very unpleasant to listen to, a complete contrast to the previous situation - Jekyll and Hyde, if you will ... hopefully, the degradation is not too great; but if it is not resolved then the playback will never totally satisfy ... which it is always capable of achieving, if the right efforts are made.

The big question is, will anyone go to this effort? If it doesn't happen then it's likely this product will also join the long, long list of also-rans, it will slowly fade as a prime target for enthusiasm by searching music lovers ...

Sunday 7 February 2016

Recordings of system behaviour for evaluation - Part 1

Finally! I've threatened to put up something of "better" quality on YouTube for awhile, and finally got around to it! This is something that probably more people will tune into, a combination of violin and piano, from a Decca recording with Perlman and Ashkenazy: https://www.youtube.com/watch?v=tfhJII7PNRM. This was just done, the system is in better shape than the first posted efforts, and the recording procedure was more carefully carried out.

The microphone is now in a "correct" position - centred in front of the speakers - so the sound more directly matches the ambience of the actual recording, and, of course the level of the raw capture was significantly higher - only 3dB of gain was needed to bring the peak level to within 1dB of the maximum. The playback system overall was not in a fully optimised state, I just wanted to get this recording out of the way, but it does give a decent sense of what the current status of the, A More Ambitious Upgrade (NAD based), system is.

The details of the previous Takes can be found in the blog entry, A More Ambitious Upgrade - Part 10 ...

Saturday 6 February 2016

So close you can smell it ...

Another satisfying session last night with the audio friend down the road, who I mentioned in an earlier post. He has taken on board my approaches to conjuring convincing sound, very much so - worrying about the most minute details at every stage. We had determined that his volume control, a motorised Alps unit, was definitely on the nose in the previous visit; so in the interim he had gone through a major exercise of trying to replace the resistive element and wiper segments with genuine Alps bits, keeping the old motor - a full replacement was ridiculously expensive! Extremely fiddly, tiny clutch mechanisms within, a problem arose ... will have another go down the track, but in the interim running with simple fixed resistor voltage divider setup that I suggested.

Along with newly adding isolation transformers and standard mains filtering parts to the rig he was very upbeat about what it was achieving ... and, the scale of the presentation was of a high order; the playback at times couldn't be obviously faulted: the bite and drive of a local R&B band recording was much improved from the previous visit. One of my favourite test albums, the original Led Zep I CD, was able to throw up cavernous soundscapes, making what is usually heard from this on audiophile systems quite farcical ... but, there was still an issue with the cleanness of the treble - the old bugbear!!

Trying to sort this out many variations were tried on the spot - the system is now at the point where the slightest alteration is immediately obvious, and the quality went up and down correspondingly. No clear conclusions as to what needed to be done to finally resolve this were reached, but there was plenty of optimism as to what was still possible to extract from the components, as is.

At times mighty close to "invisibility" of the speakers - a true mono recording makes it easy to pick this behaviour, the image of the event remains in front of your head at all times, is never perceived as originating from the drivers - this was tantilisingly near on occasion. My feeling is that he likely will manage knocking over enough of the last issues sufficiently very soon, and achieve true "conjuring" at least for a transient period ...


Wednesday 3 February 2016

A More Ambitious Upgrade - Part 18

A short update, not much has happened, but a couple of items to be noted ...

A nuisance, hopefully doesn't deteriorate more, but the NAD CD player now often is down the right channel at switch on from cold - takes some minutes of playing before it suddenly comes on line, or starts crackling and buzzing before steadily working itself fully back to stable sound. To me, this is an active component part playing up, not liking to get out of bed in the morning - once in its stride, no audible artifacts from then on in the listening, etc.

No matter how much one is aware of the fact that little things that matter, it is still easy to make mistakes! I normally carefully route all cabling, everywhere, for minimum possible interference effects to occur. But ... the speakers are mounted on flat, large slabs of MDF, to somewhat stabilise them in their very temporary location while the system is being fiddled with ... and, I had cabling, etc sitting across these boards. To cut to the chase, the vibration the speakers were transmitting to these boards was causing too much movement in the materials of these bits and pieces - the sound was being negatively affected! Tidy this up - problem solved ...

I have computer networking in the same room, no wireless, just ethernet - and it connected up and functional still causes audible interference ... I need to make the isolation and shielding yet more robust. Unfortunately, complete isolating this or any other audio system electrically from any external noise making gear is a real headache, there are no easy answers that I have found - one needs to keep plugging away until all the "gaps" are closed, for optimum sound.

Friday 22 January 2016

A More Ambitious Upgrade - Part 17

Unfortunately, not much more to report - too many tussles with other parts of the household in the interim, having things go wrong seems to go in cycles! The only real progress with the audio is that I have started experimenting with adding some interference reduction measures, which appear to be helping matters - the CD player, as I would have expected, seems to be the more susceptible - meaning, it needs an extremely clean electrical environment for there not to be obvious degradation. Wireless phones, as in mobiles and home units, are as bad offenders as they have been in the past, and I have yet to find a definitive solution for this in general - perhaps only a 100% thoroughly re-engineered system will be completely immune from audible effects ...

The system currently hovers between conjuring and non-conjuring - if all the stops are pulled out then the quality constantly delights, I can put on a CD I haven't heard in years and it's a real pleasure, the texture of the sound draws me in and immediately there's a skip in my step. But, it only takes something like a mobile phone operating in the house to cripple that, the injection of the accompanying electrical disturbance is enough to contaminate the low level detail, and the speakers become very obvious, they don't "disappear".

Also, I really must get cracking and do some proper recordings of the system playback, and upload - at the moment I can get stuck too easily in Round Tuit territory ... more effort is needed!!

Monday 4 January 2016

A More Ambitious Upgrade - Part 16

Okay, time for a quick recap ...

I'm satisfied I've got the combination of NAD CD player and integrated amplifier, and simple Sharp shelf speakers over the first hurdle: if enough care is used to control the electrical environment around it then it  conjures, very nicely. At the moment I'm playing a EMI 1964 opera CD, lovely full rich sound that expands as far anyone could want, with the speakers totally "invisible" - and the same goes for a real roughie, like the original Rolling Stones London album, played yesterday; the sound completely lifts out of the speakers.

But, I've got fixed volume, so to speak - I still haven't resolved the final solution for this, which will require trying at least one better quality potentiometer - on the To Do list. And, as I've experienced over and over again, external and possibly mutual electrical interference are problematic, the "good stuff" is only wrought when all sorts of "silly" fudges are organised for the electrical items in the house - this is a pain(!), and must be properly sorted by adding filtering and shielding as appropriate. Plus, the fixed volume I'm using is not pushing the amplifier into areas where it is substantially stressed - will the quality sustain for continuously elevated levels, like modern, heavily compressed pop?

What is very significant, is that from cold turn on the sound is highly competent, very little warm up time, if any, is necessary for satisfying replay to be had - and, almost no component substitution has been done so far: no electrolytic capacitors replaced, no swapping of other passive, and active parts done; not even the power supplies have been touched. So, there is plenty of manouvering room to enhance quality further - this is an excellent sign, the potential appears to be there for some impressive reproduction capability ...

Sunday 3 January 2016

A More Ambitious Upgrade - Part 15

Regarding the robustness of the sound quality, and awkwardness at this point of tuning, as mentioned in the previous chapter - I have a real issue with a mobile phone at the moment: switched on, even at the other end of the house it is coupling in some manner to the system, most likely via the mains power cabling - and results in the sound deadening. A flatness, major drop off in sparkle occurs, the particular interference, distortion mechanism doesn't create noise in the usual sense, but turns the sound into a much duller, "smaller", 2D version of the event - one loses interest quickly, the "life" has been sucked out of the music ...

This has been the case with all my system experiments so far in our age of the wireless phone, and it is very difficult to cure - by far the easiest solution is to simply turn off, fully, all such phones; but in this day and age this is not really a reasonable approach. A fully comprehensive solution I have not yet devised ... something for the future to sort out ...