Tuning and Musical Adventures

Tuning and Musical Adventures

Greetings Michael and Zonees

Sonic thought it might be time to start a new thread to talk about my tuning and musical adventures.  I mean the old thread title “Tuning a New World of Computer Audio Playback” actually dealt with the subject indicated in its title very quickly, with Sonic finding that the whole computer playback set up was relatively easy (I got help) and worked reliably ever since then with the recent addition of some iFi Audio accessories, that was about it. Most of that thread was about a lot of other things, which got Sonic to the point where long-standing problems with the room and system have been solved, resulting in consistent performance from the system and good musick.

This new thread looks at some new directions that Sonic is exploring. Of course, there is EQ, which I have been discussing with Michael and Bill333.

The other thing is an experiment in relation to the doors on the sides of listening room. Sonic got thinking from reading Alan Shaw’s articles on room resonances at the Harbeth Users Group (extract here edited for brevity by Sonic):

“We can use the hands in two ways - clapping together to make a load but brief 'crack' (i.e. a sonic impulse) and that will reveal useful information about the room's upper frequency behaviour. We can also form our hand into a tight fist and strike the walls, floor, doors, even ceiling if we can safely reach. Have you ever tried that? Every surface has its own natural resonant frequency.

Many UK homes like ours have thin decorative internal doors made of lightweight plywood panels lightly pinned onto a frame. They may look like solid objects but they're highly resonant.

Then I walked around the house banging other doors and walls and recorded their sonic signature on a high quality portable sound recorder in CD format. I imported the recording into an audio editor that could simultaneously display the waveform and more importantly for us this time, display the frequency response of the surface being thumped.

What do you think I found? All the doors and all the non-brick walls in this 1960s house have their own sonic 'twang' which you can hear for yourself on the recording. In reality, these seemingly solid surfaces are themselves acoustic instruments - once the critical note in the music is played by the loudspeakers, the sound wave (i.e. the bang from the first) will set them into motion at their natural frequency. And those surfaces will play 'their note' or notes as a continuous drone to accompany the music, but delayed in time and lingering long after the musicians note has ceased. That's what I call 'room bloom' or in a really bad combination of speakers, speaker placement, room construction, door construction and negligible soft furnishings 'room boom'. As I've shown on this quick example just walking around my home, we must consider that what we hear is always a combination of the speaker's latent abilities plus the sonic character of the room. The room's influence cannot ever be completely removed from the home listening experience. Not ever.

By the way, even the window glass has a characteristic low frequency sound and, being a very hard surface, is highly reflective in the middle and upper frequencies too. But for safety reasons, I don't suggest that you go around banging your windows, just in case they break.”

Source: http://www.harbeth.co.uk/usergroup/forum/the-science-of-audio/getting-the-best-sound-in-your-room-using-damping-materials/1160-real-speakers-in-real-rooms-what-to-expect-especially-in-the-lower-frequencies

Very quickly an idea came to Sonic after reading this and thumping my doors -- might the doors be the last frontier in turning my room? Might they be leaking bass and reducing the 360 degree effect that the Magneplanar MG1.5QRs and Michael’s gear are generating?  

Sonic    

Hi Sonic

Welcome to your latest thread

There's so many things I want to get to as well this summer, should be an interesting time on TuneLand

Looking forward to your adventures.

Remark from Sonic: This series of articles from Alan Shaw gives Sonic ideas on what to try on my doors.  Of course Zonees will note that Mr Shaw advocates damping while we at the Tune use controlled "acoustic burn" which is also damping (you'll find this all of Michael's acoustic products though in carefully selected amounts, always less is more, never the audiophile's customary use of huge areas of the room surfaces made absorptive), Sonic in my pursuit will stay close and true to Mr Green's principles.


Alan Shaw on Pressure Waves and an Experiment with a Beer Bottle

Quoted text starts here:

A loudspeaker in a real room ... pumping action

So what actually happens when you put a real loudspeaker (or two, three, five seven) in a real room and start playing music?

The first issue is that the room is swamped with energy - pressure waves from the speakers. If we had a super-dooper highly sensitive barometer in the room (the type that tells you if rain is expected) with an ink-pen that was extremely light weight, the nib would actually move in time with the music. So all the speaker is doing is 'inflating' and 'deflating' the air in the room according to the music, thousands of times every second. In fact, if we had Superman's muscles and lightning-fast reactions, we could achieve the same pressure-pumping effect as (a small speaker) by operating a bicycle pump really fast in time with the music.

So that's all the speaker does - wafts the atmospheric pressure at some point of measurement or listening up and down around the stasis pressure (so many millibars) just as if you were waving a large sheet or towel. And because the forward or upward going pressure can only create music in our ears if it is immediately followed by a reverse of direction giving a push-pull effect on our ear drums, the total volume of air in the room remains constant. So we'd hear music even if we hermetically sealed the room and guaranteed that none of the air escaped, and no new air entered. For example, we know from the Apollo missions that thousands of miles from earth in the airtight sealed command module, without helmets the astronauts could talk and play music. And our vocal chords are merely another way of locally modulating air pressure, and that push/pull pressure leaves our mouths and radiates away from us - detected by an ear (or microphone) as it passes them.

The essential point I want to make here is that the transmission of sound requires air to be pumped, and that pumping action both needs energy and radiates energy as a sound wave. Now consider this: we start playing music and we charge the room with sonic energy. We measure that sonic energy (with great difficulty) in acoustic watts by placing an infinite number of probe microphones in the room and adding together how much energy each one detects. Clearly, that's not practicable, so we conveniently sidestep that technical nightmare, and forget all about acoustic watts and think about power amplifier watts going into the speakers and their efficiency and directionality: a backwards but expedient way of imagining all those sound waves sloshing about like water in a fish tank.

Statement: as sound waves radiate from the speakers, they will hit surfaces. Depending upon the angle they impinge on the surface or object, the frequency, the absorptive characteristics of the object or surface, they will be reflected. Not even the anechoic chamber with 2m wedges is perfectly absorptive. Only a vacuum would neutralise the sound waves: if an astronaut removed his helmet, stepped outside the spaceship and attempted to speak, there would be total silence.

Observation 1: It follows that at best, there will be a maximum amount of sound wave energy pumped into the room by the speakers commensurate with the room's ability to fairly rapidly absorb that sound (by repeated bouncing of the sound between the objects in the room). Beyond the critical Room Maximum Sound Input (Rmsi) the room will be driven into acoustic overload, and the following notes will wrap-around into the unabsorbed reflections from the earlier notes.

Observation 2: It must be true that for every room, for a given set of loudspeakers and music, there will be a certain amplifier power needed to drive the room up to its Rmsi and that regardless of how many additional watts, or hundreds of watts are available from the amplifier, these simply cannot ever be drawn without the room's acoustic overload becoming chronic, and the sound a muddy mush. For most speakers in most rooms, probably no more than 100W is ever needed under any circumstances with any music if the room is to be driven up to but not beyond its Rmsi.

Observation 3: It must follow then that we can say, as a general rule, that a certain dB loudness as measured with a sound level meter can be used to estimated the Rmsi considering that most people listen in approximately the same size room with approximately the same absorption to approximately the same music. The critical loudness which just avoids room overload is probably about 80-90dB (a guestimate at this time) - but far lower than most audiophiles would think.

Observation 4: The WHO recommends that the public are not exposed to persistent loud sounds and that 85dB or so should be considered a relatively safe long-term listening level.

Observation 5: The speaker designer should use every design trick available to him to ensure that the speaker sound as natural as real-life even though the listener should be playing the speakers at home below Rmsi hence at a loudness far below that of the music, heard live.

Observation 6: We have to understand how the room corrupts (especially) the low frequency output from the loudspeakers, how audible that is, what can be done about it and whether it is worth the effort.

Acoustic damping - vital to tame room resonances

In the video in my post #11, I used a beer bottle as a handy resonator. I showed how this bottle had its own natural resonant frequency and with just a little energy input from me (lightly blowing across the open neck) it was set into vigorous resonance. And that's exactly how the seemingly solid surfaces in your room behave when they are excited by a little energy radiating from the loudspeakers.

As I mentioned in post #7 ...
... the best, cheapest, easiest and quickest way to reduce bass problems is .....TURN DOWN THE VOLUME. Pump less acoustic energy into the room! Then there is less to bounce around! Sit closer! ...

and that must be true because with both the air in the bottle and the walls in the listening room, there is a certain minimum 'huff' that's needed to overcome their inertia and set them into motion. And motion is an essential prerequisite to them generating sound, even though it may not be apparent to the human eye or even to the touch. But a vibration detector would readily measure their sonic contribution.

In the current version of the Harbeth User Guide here we mention the efficacy of (thick) curtains and drapes in the listening room. They need not be permanently drawn across walls - they could be drawn for listening and then withdrawn - and they should be spaced away from the wall as this magnifies their acoustic benefits. Alternatively, although more visually intrusively, the wall/door/surfaces could have acoustic tiles permanently attached. Or the existing panels could be removed and re-hung on energy absorbing joists. Whatever method we chose, the end game is to increase the amount of acoustic damping in the room because that is sure to eliminate or at least ameliorate resonances. And resonances in the listening room can never bring us closer to the music; they will always color the recorded sound by introducing tonality that just wasn't present at the recording venue. The more minimalist, bare and unfurnished the room the less the absorption, and inevitably the more the walls/ceiling/floor/door/windows will contribute to the sound.

So, back to the beer bottle and its simplistic analogy with a room surface in resonance. How can we damp its propensity to sing-out at its natural frequency? Can we apply damping to tame it and how much do we need? Do we need sophisticated materials or techniques? Will damping the air in this bottle demonstrate the importance of damping in the listening room as a general concept?

Watch my demonstration video .... http://www.screencast.com/t/rKpzH9k4F I was surprised myself.

We have to accept that in the real world, few if any of use can build a $$$ listening room engaging world-class acousticians. But if we can get the idea of acoustic damping firmly in our mind then we just may be able to turn even the most challenging lively room into one that is good enough to enjoy great sound in without spending a fortune. As I've shown with the bottle, we need only the minimum amount of damping optimally positioned. We need no more than that.

Alan A. Shaw
Designer, owner
Harbeth Audio UK

Source: http://www.harbeth.co.uk/usergroup/forum/the-science-of-audio/getting-the-best-sound-in-your-room-using-damping-materials/1160-real-speakers-in-real-rooms-what-to-expect-especially-in-the-lower-frequencies

Dealing with Doors and a Unique Loudspeaker from Japan

This is what Sonic did to reduce the bass leakage through the doors on the sides of my listening room.  What is used here are woven mats taken from a different part of my dwelling.



And they make a difference! The bass level has increased perceivably and there is a better sense of foundation to the music on everything being played since the mats’ introduction. The treble range is nicely pure.  The sound of cymbals and triangles have a nice sheen so too do the complex harmonics of the sitar and tambura.

In the couple days since this Tune, Sonic is needing the 2dB bass boost from the JVC Japan Victor Company Nivico Sound Effects Amplifier SEA-10 less.

This is a good result and if Sonic perseveres with this Tune and fully treat the doors, it might be the JVC SEA-10 might be employed in bass cut mode often.

We let this settle for a week and let’s take the measure of the sound.  I remember to check to track the progress of Sonic’s order of the Jantzen Z-Superior caps for the Magneplanar MG1.5QRs.

While we all listen and enjoy musick, here is a loudspeaker design to think about.  From Teragaki Labo:



The last picture shows how these unusual loudspeakers work. Sonic must find out more about them.

Sources: monoandstereo and  http://www.teragaki-labo.co.jp/tofficial/works/speakers.html

Sonic

About the Graham Holliman Infra-bass Subwoofer

Sonic posted something on Graham Holliman and his quest for infra-bass as the key to realism in reproduced music.  He designed a subwoofer to pressurise a room. Here are some comments from someone who experienced the Holliman infra-bass subwoofer:

Source: https://www.avforums.com/threads/graham-holliman-infrasonic-generator.1445418/

Quoted text starts:

I just wanted to post this so it would be easier to find if anybody wanted to construct a VLF subwoofer. It is an old design from the 1970's but a goody.

It is likely that the original drivers and crossovers are unobtainable now because of the age of the design, however, one could email (Welcome to the UK's largest loudspeaker supplier) or call Wilmslow Audio (01455 286603) for advice on feasible substitutions.

One friend made one in Preston (which I didn't audition) and another knocked one up in Lancaster which I did.

I think it was around about '95-'96 when I bumped into Jack who I knew from uni who said he had a friend called Rob with a DIY sub that I must check out and a few weeks later I was in this little gable attic room experiencing mind-blowing bass.

It was coming from a hand-painted white blanket box shaped thing about 3 1/2-4 foot long with a 12" woofer in the top; I can't remember the make of it but I do recall that the pre/power amp was an A&R Cambridge SA200 with the matching pre - SC150 or SC200? Dark grey with wooden side cheeks.

The wattage was about 150 per channel and you didn't need a lot of volume to 'experience' the bass wave.

It was intoxicating but it could get the better of you if you over did it.You just felt "out of sorts" and giddy and sometimes physical sickness which affected everybody that was near it when it was 'rockin.' Definately not for long-term high-level use but used sensibly it was unbelievable, totally effortless extension.

I felt it more than heard it; the room pressurisation was so intense it made me nauseous and I've never seen or heard anything like it before or since; I think that it messed about with the balance centres of my ears as well as pulverising all my organs.

You couldn't be near it for long when it was loud; maybe a couple of hours maximum.

Sonic remarks:

I have concerns about this description because any speaker that can create nausea must be pumping out lots of signal in the 6hz -- 8hz range at high levels. This sort of signals are not in any music enjoyed by people.

It might not be the fault of Mr Holliman's design, it could be the infra-bass sub was turn up too high. Though the question must be raise: where did these signals come from when playing records.

And these very low frequencies are dangerous because they don't strike one as loud. Sonic once tested a subwoofer that was pumping 20hz very cleanly.  I heard no sound but felt pressure on my ears and objects in the room started moving about.  A check on the sound level meter (dBC weighting) showed we were running at about 110dB!
   
If Zonees want to see what the Holliman device looks like and how to build it, diagrams, plans and discussions can be found at DIYAudio.

Sonic

Empirical Wisdom

You probably wonder sometimes why I don't come up a debate some of these theories, maybe not.

There's basically two reasons. One is the lack of time and repeating myself. The other is, you are past the stage of beginner audiophilia-ism.

When I have taken the time to read some of the theories by others you report on and quote, it throws me back to when I was in my late teens or early 20's when I needed to do these tests and listening sessions for myself. You try something and get a result, and then go on to develop a reason why, or theory. That's what I see when I read these reports by others. It's also why I prefer developing something that I feel is deeper and more personal than theory building. For myself, theory building has too much ego involved and tends to stop the student approach to knowledge. Empirical wisdom however always stays fresh and in motion. Being empirical is a process, an art form, more than a fixed rule or measurement.

While your doing your dampening, you should do a test and report on what you find. Stand up from your listening chair and walk toward the direct dampening you put on the door talking and using your voice and body as your measuring tool. The closer you get to the door the more you will hear it's plus and minus contribution to the room and how the room and your body is reacting to the direct material. By the time you get about a foot from the material you will be feeling and hearing the interaction taking it's plus and minus toll on your bodies system. Once you get inside the laminar flow you will hear, and sense, the affect on you and the entire wall.

Without the theories tell us what happened. Take down the material and do the same thing. Now have a friend and you do the same tests with you taking turns being on each side of the door.

The reason I'm saying try this is because I have made (built myself and had built for me) my share of listening doors and studio doors. I've also tested a lot of doors for studio applications from other designers. Tunable and none tunable, as well as double compression doors, and even vacuum seals. Reading some of the audiophile theory, and we can extend this to studio theory, I find quite a bit difference between the reality and the assumed theory. I'm not trying to 'dampen' (pun) these guys, what seems to me to be some what limited views and theory building, but, there are some common sense issues in their writings.

the bottom line for me is

I enjoy watching you grow, and as I see with Bill333, becoming your own masters of your hobbies. With Bill and you and the audio folks you quote, it all comes down to learning and how you (we) all as individuals become 'expert' in any of our tests and findings. This is certainly a hobby where winning takes practice. And finding the truths is both individually and variably based.

recorded codes, audio codes, audio chain and the tools and Empirical Wisdom we develop

always good reads Sonic, just wish I had more time in the day

"a.          the material of what is on the doors affects the sound:  Presently what I have up is a kind of woven mat of a plastic material which is made in Finland – which is what I been reporting on."

noted

Could be a nice blend for your room, as well as being a front for some slight burn behind them.

If you have a website on the material please forward it to me, thanks.

Hi Michael

Those rugs were bought in person on a trip to Finland many moons ago, and they have no tags indicating brand name or material.
They are not Ikea stuff.

However, there are a thing called swedish plastic rugs which are popular and one website that has them for sale is:
https://www.scandinaviandesigncenter.com/Products/usd0/Scandinavian_Carpets/Pappelina+carpets

In the meantime, Sonic is learning more about tuning the doors. There is more to it than hanging semi-absorptive surfaces on them.

My Learning -- Coupling the Doors to their Frames is the Source of the Improvement
This is what I mean -- some testing has shown Sonic that the bigger, deeper bass from treating the doors come from actually coupling the door panels to the frame and the walls tightly. The effect of a mat hung on the doors has the same effect but not to such a great extent.

What I mean is the door pairs when untreated are actually hanging free from just the hinges at the sides, a pair of bolts and a lock. The rest of the doors do not touch the door frame.

Michael, how shall I couple the doors to the their frames along the door panels' edges  

In the DIY stores, there are sound and weather-proofing products that are rubbery D-section tubes that one can glue to the door frame and when the doors are shut, they compress the rubbery D-section tubes and offer some coupling to the frame.

How would you create the coupling and seal along the edges of the doors? For the tune I know rubber, like cotton, is to be avoided wherever possible.  

Sonic

Greetings Zonees!

Michael’s got a point (doesn’t he always?) when he suggested to Sonic:

“While your doing your dampening, you should do a test and report on what you find. Stand up from your listening chair and walk toward the direct dampening you put on the door talking and using your voice and body as your measuring tool. The closer you get to the door the more you will hear it's plus and minus contribution to the room and how the room and your body is reacting to the direct material. By the time you get about a foot from the material you will be feeling and hearing the interaction taking it's plus and minus toll on your bodies system. Once you get inside the laminar flow you will hear, and sense, the affect on you and the entire wall.”

Following Mr Green's pointer, Sonic has tested and the learning is that the doors are significant but while the Scandinavian plastic rugs on the wall help some, they have a “minus” contribution to the room sound. The bass has increased but the life and transient pace is weakened. Moreover, after settling there was slightly but perceptibly more bass on one side of the room than the other. Not exactly satisfactory.

I am waiting to apply the TPU polymer seals and that might stabilise the doors while allowing the rugs to be removed. This will be next week.

So for today here is an article Sonic found by someone who was something of an audiophile authority in my town at a time in the past, this piece dating from the early 2000s. T S Lim is a designer of gear like phono stages and amplifiers. Lim is reportedly an expert harmonica player and a member of the Singapore Mahler Society. While this post is not Sonic's endorsement of any of these views or the products mentioned, I hope Zonees will find their views a good read and an insight into audio in this part of the planet.

Musicality
By Richard Seah

A RICH AUDIOPHILE once invited a musician - a Chinese orchestra conductor - to visit his home and listen to his hifi system. This was quite many years ago, when the audiophile's $60,000+ set-up was one of the most costly in all of Singapore.

When he entered the house, the musician was visibly impressed with the audiophile's collection of paintings, calligraphy, ceramics and other works of art. This was indeed a man of fine taste.

But when the music came on, the musician was not impressed at all. He frowned. He shook his head.

Now the audiophile, although very rich, is also very humble. He sincerely asked the musician, "What's wrong? If you have any suggestion on how I can improve the sound of my hifi, I will surely implement it."

"I don't know " the musician replied. "I have played this same music in my home many times and I am very moved whenever I listen to it. But here, I don't feel anything."

"What hifi equipment do you use at home?" the audiophile asked.

The musician was embarrassed to say. But when pressed, he finally revealed: "A Philips mini-compo."

The above story was told to me by DIVA designer T S Lim, who often uses it to illustrate what is meant by "musicality". It is a term that is, ironically, seldom understood by audiophiles who spend a great deal of time supposedly listening to music.

Audiophiles usually talk about bass, midrange and highs, about soundstage and imaging, about resolution and detail, about dynamics, including macro dynamics and micro dynamics. They talk about sound, not about music.

Yes, sometimes they talk about "musicality" too. They would make a statement like "this amplifier is very musical". But the term is often used very loosely and generally. What, exactly, does it mean?

It took me a long time to find out. It took me a long time to understand why Lim, when he listens to hifi, would make comments about the singer's vocal techniques, or about the conductor's reading of a score, rather than about the highs and lows that "normal" audiophiles talk about.

After a while, I begin to get the idea. A few times, while listening to "unmusical" hifi systems, I ever got the feeling that the performance was somewhat mechanical, as if it was a machine rather than a human playing the instrument.

I had this feeling once during the harmonica solo on Holly Cole's Tennesse Waltz (Don't Smoke in Bed album.) This was in a customers' house. I suggested switching his preamplifier, and the feeling changed.

I think it is easier to detect this feeling on musical instruments because the human voice will somehow sound "human" even in "unmusical" hifi systems.

Bach's music, especially his solo violin and solo piano pieces, are a good test. The nature of the music is itself somewhat mechanical. So when it is "unmusical" it will sound terribly mechanical and downright boring. But when it is musical, the same music can be a joy to listen to.

What makes music musical?

First and most of all, it is the performer. If the performer has little musicality to begin with, even the best hifi system will not help. In fact, hifi equipment can never help improve any music. The best they can do is minimise the extent of damage to the music.

After the performer comes the recording - the recording equipment, the process, the pressing, and so on. If you have a chance to compare different versions of the same recording, you will have a good idea. For example, in the Japanese pressing of Faye Wong's Tian Kong album, Faye's voice actually sound a lot sexier!

The way your hifi is set up will also have an effect. This happens all the time in my shop. In the process of swapping equipment and cables for demo, the isolation cones get shifted. (I use mostly DH Ceramic Cones, plus now a new brand, "Qi Cones".)

When the cones get shifted, the singer's expression changes! And it is frustrating for me not to be able to it get back right. I do not yet have enough set up skills.

Of course, the actual equipment plays a big part. Almost everyone who auditions the DIVA amplifiers remarks that they are "very musical". Because DIVA designer T S Lim is more concerned about making his amplifiers sound musical than anything else.

One recent DIVA customer, Lee Fatt, puts it well when he wrote: "It's never before since the last 8 years that I have enjoyed music more - sounds so musical, the voices so emotional, so involving. I can even enjoy songs from badly recorded CDs because of the amp's musicality and emotional involvement, yet forget the rest of the audio quality."

Musicality need not come with a heavy price tag, as the above example of the Philips mini-compo shows.

T S Lim has told me for many years that the inexpensive Marantz CD63 is a "very musical sounding CD player". He says it is more musical than even many of the ultra-expensive CD players or CD Transport / DAC systems, including those costing tens of thousands of dollars.

Really? I was never really convinced until early this year at CES 2000 in Las Vegas. Lim and I had taken part in THE SHOW (which is held in conjunction with CES) to exhibit his DIVA amplifiers. We shared a room with ReTHM horn speakers and DH Ceramic Cones.

We paid considerable money to take part in THE SHOW and we had to compete for visitor attention with several hundred other exhibitors, including some of the world's "best" hifi brands. We had to get the best possible sound - the best possible music - from our set-up.

So Allen Chang of DH Cones offered to bring along a Sony SACD player, the latest new technology CD player which many audiophiles and audio reviewers have been raving about.

Lim's reaction was "But is it musical?"

He felt it would be wise to bring along his (modified) Marantz CD63 just to be safe.

When we compared the two CD players, the three of us (Lim, ReTHM designer Jacob George and myself, Allen was not present) very easily decided which was more musical: the Marantz wons hands down!

On the Marantz, the music simply sounded more "correct". It sounded more like music. I don't know how else to describe it. But the difference was so great that, in less than a minute, we unplugged the SACD. We did not even think about resolution, detail, soundstaging, etc etc. All that was irrelavent.

On to a more recent hifi show, AV Fest 2000 in Kuala Lumpur, Malaysia, 4 to 6 August 2000.

At a seminar during AV Fest, Lim was scheduled to give a talk on "The Art of High Fidelity", to be followed by a talk by Jacob George. Since Lim's DIVA and Jacob's ReTHM were exhibiting together, they decided to present their talks jointly, with a live demonstration.

Scheduled just before them was Kondo San, famed designer of the world's most expensive - and some say, "the world's best" - tube amplifiers: the Ongaku (S$100,000+) and Gaku On (S$300,000+). Kondo San's topic was similar: "What is Good Sound?"

Lim, Jacob and I discussed the issues over several nights: What is High Fidelity? What is Good Sound?

High Fidelity means "highly faithful". It means reproducing sound that is as close as possible to the real thing. Among other things, it means accurate sound reproduction, with the lowest possible distortion.

But is this also "Good Sound?"

It is easy enough to agree that lower distortion is not always better sound. Many cheap brands of mass market amplifiers have extremely low distortion - in the region of 0.00... % Yet they don't sound good at all compared with some high quality tube amps with distortion figures of 2% or 3%.

Can highly distorted music sound good?

Take, for example, the ablum of old Chinese songs, recorded by Lee Hsiang Lan during the 1930s. The music is highly distorted, sounds very far from real, live music. Yet Hong Kong audiophile magazines say the music will "transport you to audio heaven". It stirs the emotion, it moves the spirit.

"That is good sound," Lim declares.

Jacob and I disagree. We argue that while it may be good music, good performance, it is still "bad sound".

Distortion reminds me of modern paintings such as those by Piccasso: one eye here, another eye there, nose and mouth totally out of place, totally out of proportion, totally distorted. Yet they are considered "good art". Why?

"Because it captures the soul!" Lim explains. "Not everyone has Piccasso's ability to paint a distorted picture and still capture the soul."

Yah! Agree!

By the same token, not everyone can snap a photograph - which gives an accurate picture - and capture the soul either.

We spent many hours talking about such things. In the end, the conclusion I draw is that, yes, "High Fidelity" means "highly faithful to the real thing, the real music." But there are two levels of reality - the physical reality and the reality of the soul.

Physical reality is about sound vibrations - how close does the music from your hifi approach real, live music. Reality of the soul is about the emotional content - to what extent does your hifi convey the emotion of a musical performance?

This second reality can be called "musicality".

It reminds me of yet another story which I once read in a US hifi magazine.

A hifi dealer wanted to impress his customers, so he played a solo piano recording through his hifi. Midway through, he faded out the music and his wife took over, playing the piano "live" in the next room.

The audience could not tell the difference. They were impressed.

Except for one. He told her hifi dealer: "Congratulations! You've just succeeded in making a world famous pianist performing on a Steinway sound like your wife playing on an upright piano!"

Source: http://www.echoloft.com/soulofmusic/musicality.htm

Ever Wondered What Is The Difference Between VTA And SRA?

VTA adjustment is passe. Now audio people are talking about adjusting the SRA (the Stylus Rake Angle). Here is a good piece explaining the difference.

Source:  https://www.audioasylum.com/audio/vinyl/messages/1240.html

Quoted text starts:

SRA vs. VTA

Enough is enough! Here is a summary of the differences between SRA and VTA.

VTA or vertical tracking angle is the angle the cantilever makes with the surface of the record. Typically in the range from 10 to 30 degrees for cartridges, this should be matched to the VTA of the cutter head cutting stylus's pivot angle as it cuts the record, which can be likened to a defined length and pivot point, ala the phono cartridge.

The cutter head swing arm angle is a relatively fixed value for the various brands of cutter heads, and unless adjusted in the field, should remain very consistent in the field for all cutter heads of similar make and model. The range of modern VTA is approx. 24 degrees to 18 degrees, with most cutter heads being adjusted to around 22 degrees.

If the VTA of a phone cartridge is off, it will generate FM distortion (2nd order), and in almost all cases, will not be audible unless the cartridge is more than about 4-5 degrees off, and then only under ideal conditions of perfect alignment otherwise, and a highly resolving system.

One factor that CANNOT be matched by the user is if the arc length of the cutter head's effective swing arm length matches the cartridge cantilever length from pivot point to stylus tip. This mismatch will generate 3rd order FM distortion products, but again, has to be fairly far off to cause an audible problem.

SRA is stylus rake angle, or the angle the contact edge on the side of the stylus makes with the record groove. It is usually expressed with respect to the surface of the record, with straight up and down being zero degrees. For spherical sytlii, there is no SRA, only VTA, and then you can adjust for VTA without regard to the stylus angle. For eliptical and fine line stylii, there is a defined and relevant SRA.
Getting the stylus contact line to line up with the HF modulations of the groove wall is similar to aligning a tape haed to the recorded waves on the magnetic tape: you want them to be totally parallel with one another. When a fine line stylus is not aligned with the groove wall in terms of matching the SRA to the record walls groove angle as cut by the cutting stylus, then the footprint of the stylus will be riding over more than a single HF groove wiggle at a time. This results in a loss of HF's, and a blurring in time of the recovered signal, just like on a tape deck. If that was all that occurred, then incorrect SRA would be rather benign.

However, the situation for the groove wall is not like that of the tape deck, the groove wall and stylus are a mechanical interface whereby the groove wall modulations can torque on the stylus edge as it passes over the modulations at a rake angle that is not the same. This tends to generate spurious signals that are not harmonically related to the original signal, and the torquing tends to cause the intrisnic cartridge cantilever/moving system resonances to be excited and stimulated. The result: hash and HF frazzle that reaches surprisingly low in the audio band due to intermodulation with the signals being recovered from the record groove.

The distortion levels for SRA are much higher, and much more irritating than for the VTA distortion. This is because they are aharmonic in many cases, and the IM reaches down into the midband.

So when adjusting the angle of the cartridge/tonearm system, SRA should be the parameter being adjusted for, not VTA.

If you have any doubts about how to set this via my info, follow your cartridge manufacturer's recommendations. They usually specify that the top of the cartridge body be parallel to the records surface at the nominal recommended tracking force. However, if you use a tracking weight different than the middle of the tracking range, or the "recommended" weight, then the angle will be slightly off.
You can actually see the angle of the diamond chip that is the stylus, as most stylii have the diamond chip shank axis the same as the contact line axis. One of the notable exceptions was the old Shibata style stylus, which had the angle of the stylus rake different from the angle of the whole diamond chip/shank, and the contact line was actually slightly curved in the vertical. Using a penlight or maglight flashlight, have someone illuminate the stylus tip from behind (center of record) while you look at the cartridge from the side while it is in an outer groove on a flat non-warped record. With either a bit of squinting or the aid of a magnifying glass, you should be able to see the diamond stylus shank extending down into the groove. Really, all you will be able to see is the part that sticks up from the groove, and through the cantilever on the top side.

After studying the range of modern cutting lathes, it was determined via measurement and listening tests that the optimum SRA was a value that would provide decent playback on most records, without resetting the SRA for every individual record, was approx. 1 degree forward (top away from the tone arm pivot).

If you back illuminate the stylus as related above, you should be able to see the diamond chip's angle, which corresponds to the SRA. It should definately not be tilted back (the shank top toward the tone arm pivot).

If you make up an index card with a straight up line and a line 1 degree off of that tilted in the proper direction, you can use such a card as a visual aid in aligning the stylus chip angle. [Remark from Sonic: Jon issued a subsequent correction -- that it was 2 degrees not 1 degree as given here, that is 2 degrees leaning in the direction of record rotation]

This set it and forget it SRA alignment will playback 80% of all records with a minimum of average SRA error, usually within a degree or two of the record groove walls rake angle. Anything less than 0.5 degrees off of exact alignment for a particular combination of groove wall rake angle and SRA is not very audible, although an error in the direction of too high at the tonearm pivot (shank top more away from the tone arm pivot) will tend to sound worse. That is why this average SRA angle is biased toward a slightly higher average error in the benign direction, and not the other way.

This adjustment will at least get you in the ball park for a starting point. It helps to remember that if you adjust the SRA by ear for a particular record, you may be as much as 5 degrees or more off for another record.

For the published version of this, see:

November 1980 Popular Electronics article titled: "Phonograph
Playback: It's better than you think." by myself and Dr. Maier, p. 48.

AND

High Fidelity in the March, 1981 issue on page 31.

AND

Audio magazine, March 1981, page 21, "More Than One VTA",
again by Dr. Maier and myself.

Jon Risch

The Primacy of "King Tone"

Sonic will only get the next batch of TPU seals this weekend to complete sealing the doors.  Though with a week of settling I am very pleased with how the sound has gained tonal fullness.

This brings me to an idea that has been growing in Sonic’s head – that tonal correctness and beauty is the Primary Defining Quality of a music system ahead of everything else.  King Tone they call it.

What I mean is when we are first introduced to an audio system and hear the first notes, the first thing that strikes us as good or off is the Tone – only after we take the measure of the Tone that we think about imaging, soundstage width, holographic effects and all those other things.  I will venture that after Tone, the thing that very quickly strikes us next may be Dynamics – the attack and “jump factor” or the absence of it. Then step by step we take the measure of imaging, soundstage etc.  
 
And if the Tone is wrong, any of those things following even if they are right or even spectacular become irrelevant.

Meaning Sonic has heard orchestral music through some very expensive mini monitors and I recall the sound as thin, bass-light, foundationless.  Yes, the soundstage was much wider than the spacing of the speakers, the imaging had what some will call “layering” but with the Tone wrong, this mini monitor system with all its expensive tubed amplification was unpleasant.

“King Tone before all else” thinks Sonic.

Till I report on the completion of the door sealing project, have a look at this:



Source: http://jeffsplace.me/wordpress/?p=9495&cpage=1

Sonic

"Following Mr Green's pointer, Sonic has tested and the learning is that the doors are significant but while the Scandinavian plastic rugs on the wall help some, they have a “minus” contribution to the room sound. The bass has increased but the life and transient pace is weakened. Moreover, after settling there was slightly but perceptibly more bass on one side of the room than the other. Not exactly satisfactory."

BINGO



Welcome to my world Sonic

Always being a student of what is missing, as much as what is there, builds tuning wisdom.

Stuff from Bob Ludwig including a view on “What is Musicality?”

For the full interview go to: http://tapeop.com/interviews/105/bob-ludwig/

On the other hand, there's music that works especially within the boundaries of limited sound quality. Bruce Springsteen's Nebraska comes to mind, which is haunting, despite its "lo-fi" 4-track cassette sound.

With Nebraska, Bruce and his producers remixed the 4-track Portastudio cassette through a Neve console and an SSL console, but Bruce liked the cassette. I got a Nakamichi Dragon, a state-of-the-art cassette machine. I corrected the azimuth and speed of the tape, but Bruce liked it left alone — running quite slowly when played on a proper cassette deck. A few times during the years, when "Atlantic City" became part of a compilation, I would ask Bruce if he wanted the speed corrected to the same 440 [Hz] pitch he used when he sang it, and the answer is always, "No." It is what it is, and it is a work of high art.

Just recently I did a project with Jack White and Neil Young, called A Letter Home. Jack White refurbished a 1947 Voice-o-Graph vinyl recording booth, used to make one-off disks to keep, or mail to someone, to hear on their phonograph. It's almost impossible to keep on-speed, and, by design, the recording sounds not only like a 78-rpm disk, but a well-worn and ravaged one at that! Jim Farber at the New York Daily News brilliantly said it was "like some audio equivalent of a message in a bottle, long ago tossed into the sea." The record is sometimes hard to listen to, with lots of ticks, pops, and other noises, but it is 100 percent vibe and it works beautifully. A project totally worthy of the extreme effort they went through to create it.

You've referred to mastering as "the idea of bringing out the musicality of the material." Could you try to define musicality a bit further?

Musicality is a function of one's reaction to what one is hearing. Good mastering can bring out many details in the sound that might have been lost in the original mix. One can hear the details better and react to the subtleties that are inherent in the music. I would say it brought out the musicality inherent in the sounds that were recorded. When I master, I not only treat each song differently, if it needs it, but I consider every note of a piece to be sure everything is as good as it can possibly be. Sometimes a single bass frequency may need to be dipped for one note.

With digital masters, does a transfer to analog tape help to imbue musicality?

It is a case-by-case situation as to which is better. For most mix engineers, mixing to analog tape can beautifully glue the sound of their mix together in a way that digital can't — so far! However, for engineers like Bob Clearmountain or Chris Lord Alge, what comes out of the console is exactly what they want to hear. The soft saturation and head bumps — the warmth of analog tape — now become a bit muddy and lacking in clarity. Some producers of projects with limited budgets, where it was recorded and mixed in digital, have asked me to transfer the approved takes to analog tape and master from that.

I would say that 30 percent of the time it works beautifully, and 70 percent of the time it doesn't. Those times that it does work, it is an amazing thing, and I still wonder why a transfer can imbue so much musicality into the sound. If you are doing a pop project, checking out the sound of capturing your mix on analog tape is a worthwhile exercise if you can afford it. For me, the choice of tape machine, the choice of the electronics, the brands of tape, and the way the tape machine is aligned can give me plenty of choices to determine how the transients and saturation sound.

You once said that today's converters, with great clocking, cannot be differentiated from the analog source by anyone you've tested.

I'm not saying that no one can ever hear the difference, I'm merely saying when someone comes into the studio for a quick visit and I play the source vs. high resolution digital, a 96 kHz, 192 kHz, or DSD copy, no one can immediately pick out the difference. Don't forget, these are all awesome converters. The quality of the engineering of the analog-to-digital converter and DAC is much, much more important to the musicality of the sound than the sampling rate could ever be.

Our $8,000 converters at 16-bit/44.1 kHz sound way, way better than a 192 kHz playback from a $5 chip on a DVD-Audio player. I think the higher resolution sounds reveal themselves not in A/B testing, but in long periods of time. Play an entire album in a relaxed atmosphere at 96 kHz/24-bit, then, at the end, listen to it at 44.1 kHz/16-bit, and you'll get it right away. A/B testing, while the only scientific method we have, does not reveal too much with short-term back-and-forth comparisons due to the anxiety the brain is under doing such a test. The brain becomes very left-brain-technical, rather than right-brain creative and musical.

sonic

1. So Michael, since our recall of musical events is prone to inaccuracy.  You offer tuneable speakers, tuneable rooms and tuneable room treatments.  How do I ever know if I got it right?  

mg

The simple answer is, if you don't use the same method used to create what is "right" your playback will always be inaccurate.

sonic

2. Is accuracy and fidelity important at all?

mg

I've yet to come across any audiophiles who interpret a piece of music the same. What is accurate, and important to me, may be way off from what is important to some other listener. Playback is a sport of 'variables', so is the recorded code.

Audiophile myth creators tell their stories of what should be, many times, based on if the universe was not a moving continuum. If we truly got into how many versions of listening there were of the same recording the collective audiophile brain would explode. The variables and opinions is what keeps the hobbyist's mind engaged. However there are even huge differences between the many types of audiophiles. Each of these types look at any performance through their own lens.

My job is to create tools, as usable as I can, that allows the listener to be part of the debate of accuracy and fidelity. Does the end user get to their listening goal, is always on my mind. Me saying "something is accurate" would take an entire forum to explain. Thank goodness that's exactly what we have, an entire forum.