Step by step surgery

[fas42]

OK, new topic for anyone interested in my approach - to prevent the Concert Hall sound thread being mutilated any further ...

 

To repeat my last post there, which Chris may wish to remove,

 

8 hours ago, semente said:

 

Would you mind describing the surgery step by step?

 

 This is grotesquely off-topic now, but for the sake of answering in the first instance here is what I posted in my blog in October 2015, word for word, https://www.blogger.com/blogger.g?blogID=8257461568062445791#editor/target=post;postID=3859634021411227148;onPublishedMenu=publishedposts;onClosedMenu=publishedposts;postNum=31;src=postname:

 

Quote

 

I've been motivated to fix up and optimise another cheap system: some discarded NAD units, almost 20 year old CD player and amplifier driving good, "boombox" speakers. Very promising early signs, tonnes of genuine dynamics in the raw state; has the usual flaws of developing a very 'dirty', unpleasant edge with steady playing - quite a bit of cleaning up and tidying to be done, but excellent potential ...

 

There's a NAD C 540 CDP (CD only player), 304 integrated amplifier, and Sharp boombox speakers - from a classic, modern 3 identically sized boxes with all the electronics in the middle system; the speakers have a solid bass/mid unit, rated to take 200W, so no prob's there.

 

As usual, all the issues are with the electronics: to start with, the full setup had a cheap but cheerful sound, at least for a while from startup, until the electronics got really a dirty tone with ongoing use. As expected, the internals are riddled with weaknesses, poor implementation details, which all have to be sorted - the unfortunate thing is that mildly ambitious units like the NAD get lots of things right, but all the leftovers then combine to drag down the potential dramatically, they often sound considerably worse than a very simple, totally unambitious sound unit, in the sense of being less "musical".

 

Which is a way of saying that I'm in that awkward middle stage of tweaking, where quite a number of flaws have been bypassed, lifting the standard in some aspects, but putting the remaining ones in much sharper focus - the whole now very easily produces downright unpleasant sound, ? . Many people could give up now, saying they preferred the easier to listen to, somewhat gunked up sound of the raw units - but that would be a failure of effort, big time !!

 

The CDP has a pretty hopeless reader mechanism engineered, CD-Rs are a huge obstacle, sound much worse than an LP with continual crackling and popping as the error correction struggles, all my other rubbishy computer and audio CD drives handle these disks with zero audible problems. But, NAD is known for this, ?   - will explore some avenues here.

 

My other recent fiddling with cheap stuff was much easier, because so many flaws were eliminated by virtue of close integration of the electronic elements - the designers got that part right! The NADs, like nearly all of this type of electronics, have flaky elements everywhere  - and each and every one has to be tracked down to get the best out of the whole.

 

A couple of thoughts on current progress: can do big orchestral climaxes with greater SPL than my other recent efforts, but tonality still has some way to go; massed strings, piano and such are often not right, sweetness goes off far too quickly ...

 

 

 

 

 

Woah, time flies!! ... That long ago ...

 

That's part 1, there are 12 more parts to it.

[semente]

Thanks, I'll have a look.

 

As mentioned before, I have a friend who used to modify commercial gear, he's getting ready to go commercial with his own brand soon, and in most cases the improvements were easily noticeable.

My integrated was designed and built him, a design developed over 15 years, and he modified my Pioneer PD-91 CD player. I don't have access to it at the moment or I would post a couple of photos.

But to illustrate my point here's a photo of an integrated amplifier modified by another person I used to chat with in a Portuguese forum:

 

 

A good caption could be from messy to optimised... KISS.

 

All commercial equipment can be modified/optimised, even that which is already performing at a very high level.

[fas42]

See how you go! George has got beside himself with wanting to see what "I had done" - and I popped the lid yesterday to see if it was worthwhile taking a shot ... ummm, no. Barely able to see anything above - the only obvious visible aspects are that the input sockets are bypassed - cable from the CDP are fed through a convenient gap, and hardwired to the board. Likewise, the output is taken from a convenient place within the box, from the wiring going to the output terminals, and clumsily fed over the side. The last bit is that the volume pot has been rewired, and fixed, normal resistors dictate the gain - also impossible to see.

 

I'm not in the mood to manoeuvre everything to be able to take the bottom plate off - subtle open and short circuiting of traces has occurred here; which tell one nothing, visually.

 

A much better link to dive into this "story"  is https://artofaudioconjuring.blogspot.com/search/label/Tweaking. And I note now that I had posted 18 instalments - I had gotten the wrong tally from elsewhere.

 

The clearest message is that it's all about listening - feedback from how it sounds guides one; it's the starting point, and one becomes more demanding for higher standards to be met as the SQ is steadily pushed upwards.

[fas42]

This track,

 

 

was pointed to in another thread,

 

This is good material, as I stated in a following post, for diagnosing system issues - a first step before actual "surgery" .

 

OK, hands up those who can see what I'm talking about, after watching this clip - and also comments from those who think I'm mad ...

 

[fas42]

I was reminded of a favourite from years ago, by this clip ... the ending of this next song is the point of this one - how does it come across?

 

 

[fas42]

Went to a meeting of creative people in the area, i.e., artists, last night who want to branch out a bit in what they do, the ol' cross-fertilisation concept - mentioned the ability of creating convincing playback, and the organiser was quite intrigued; suggested having evenings, in the meeting area, where such can be put on show, to provoke thinking and interest in audio as a means of being creative, and inspired, etc.

 

This could be the push to motivate me to get the NAD rig in proper shape ... stay tuned ... .

[fas42]

My 'method' mystifies people, it seems - because at its heart it's so simple . Just had a thought, about presenting it slightly differently - perhaps it might trigger something of value for someone ... after all, miracles do happen ... .

 

Step 1)  Accept that the circuitry of the gear in the system is essentially good enough to do the job, no fundamental alterations have to be made with "how it works" - irrespective of cost, street cred, etc, etc.

 

Step 2)  Pick a recording to assess the playback quality; ignore your "good" recordings - ideal is one that you so wish was better than it comes across, but has a major factor in its perceived quality that really irritates you, that occurs throughout the track - a single instance of some "glitch" or peculiarity is almost useless; it needs to be a "running sore" that makes you almost hate listening to it. For me, at one stage this was the quality of cymbals in a drumkit - white noise didn't strike me as musically interesting ... .

 

Step 3)  Play the track and then start altering the system, and the environment, in any which way you can think of - and pay very close attention to precisely how that irritating quality comes across - the only thing that matters is whether the character of the disturbing sound alters, whether it gets better or worse is not the point - all you are looking for, is a change ... . Many things may do nothing whatsoever - and that's a good thing! When, or if, you stumble across some factor which impacts the sound element you're paying attention to ... Bingo !!! You have now established that the setup is sensitive to some factor which is altering the audible distortion spectrum and/or levels in the playback !

 

So, what do you do to "alter the system, and the environment"? And what do you do, when you've found a "sensitivity"? ... ... I'll leave that to a next post ... .

[fas42]

As a slight diversion, I'll describe what's happening with one of our vehicles - it has, gasp!!, electrical problems; the battery went flat, dead for no obvious reason - apart from age ... and it's been a little circus since. Well, I'm a DIY chappy from way back - will I pay someone exorbitant money, to sort it all in the comfort of his hideout? ... Guess not ... .

 

This means, on goes the troubleshooting cap - the very exact same one I use with an audio rig ... so, will this save the day?!! Well, I'm getting a lot closer to resolution - wait for the next thrilling installment! And when I have a satisfactory result, I'll spill the beans ... all of them .

 

This is magic, conjuring, in action, folks ...

 

BTW, I'm sorry I didn't use a DBT, or an in depth statistical analysis to determine if I really had a car problem ... maybe, next time.

[fas42]

The battery saga continues ... no final resolution so far, waiting for a part.

 

In the meantime, I will comment on the Lush^2 thread here, rather than pollute Peter's platform. I note that some people are using this cable to season their system's tonality - and this is not the point! One is aiming to hear what the recording contains; not add viewing filters, like a Photoshop exercise - honesty to the capture of the recorded event is the best solution, because it gives the maximum long term listening satisfaction.

[Ralf11]

thread title suggests emergency tracheotomy

[kumakuma]

Frankendectomy

[fas42]

On Tuesday, 25 September 2018 at 4:01 PM, fas42 said:

As a slight diversion, I'll describe what's happening with one of our vehicles - it has, gasp!!, electrical problems; the battery went flat, dead for no obvious reason - apart from age ... and it's been a little circus since. Well, I'm a DIY chappy from way back - will I pay someone exorbitant money, to sort it all in the comfort of his hideout? ... Guess not ... .

 

This means, on goes the troubleshooting cap - the very exact same one I use with an audio rig ... so, will this save the day?!! Well, I'm getting a lot closer to resolution - wait for the next thrilling installment! And when I have a satisfactory result, I'll spill the beans ... all of them .

 

This is magic, conjuring, in action, folks ...

 

BTW, I'm sorry I didn't use a DBT, or an in depth statistical analysis to determine if I really had a car problem ... maybe, next time.

 

Resolved.

 

It was the voltage regulator, a small, intrinsic part of the alternator - on some designs you have to remove this device for charging the battery from the vehicle - with some accompanying swearing; dismantle the alternator end, and changeover the tiny part; and then reverse removal procedure, with more swearing. I was lucky, it could be done with all remaining in place; took about ten minutes or so to do.

 

What made it tricky was that the charge warning light behaved completely normally; it illuminated when key went into the ignition, and then extinguished. And stayed that way until the electricals died.

 

The battery "died" one morning in the garage, when the car was needed for an errand. We had had exactly the same thing happen for the other vehicle, which was sorted by a new battery - the battery was many, many years old - it had to be the battery! Okay, run down and get a new one, on special - bugger!! Even though there was nothing I came across that made this clear, the terminal posts were the wrong size, too small! Okay, devise some shimming, big thick copper to get a decent connection for the starting current - beautiful!

 

Did some short trips, everything fine. Then went for the regular two hour exercise - and right at the end, the car wouldn't start ... What!!! Checked the battery connections, wasn't happy with how the shims were making the connection secure - must be my fault! Got it home, from jump starting, everything fine. Did an extra round of making the shims secure - this will do the job!

 

Long story short, this happened three times! Yes, three times - car was sweet after I made extra effort to get the battery leads firmly locked onto the battery - in the final round, it was super rigidly locked on. After securing tightly I checked the voltages, yes, good healthy volts were present while the engine was running.

 

Looked up other people's experiences - couldn't see anything matching. Did I have a dud new battery?! Unlikely, but always possible ... went to the store, they played hard ball - wisely it turned out - and charged the battery overnight, and did a full round of checks - it was good! So, what now?

 

It had to be the charging circuit! But, once the car was jump started, it ran perfectly to get it home, and started again cleanly when it needed to - the battery was being fed lots of lovely amps some of the time, but not all the time - with no indicator of malfunction.

 

More Googling - ah-ha!! Someone had had the precise same symptoms as me, but because of the circumstances he got the answer straightaway. The charging circuit worked perfectly when the engine wasn't in a fully hot state - but suddenly went missing in action after a solid mileage was under the wheels. With no indication from the warning light. Did some laps in mine, and confirmed the abrupt loss of charging voltage, at a certain point.

 

After some phone calls to confirm best action to take - replace alternator, or just the suspect part? - was told by chap who reconditioned these units that he didn't use the correct replacement part - they were unreliable!! So, organised a sample of the substitute he used to be sent, and after an unexpected delay to arrive, it was in. And so far, so good ...

[fas42]

Something like, "It never rains but it ..." ...

 

Only just sorted the car, now the HP laptop has decided to go bad on me, .

 

Will retrieve the hard disk data, and pull the case apart, see if anything obvious to be seen ... it's mighty elderly, so just might let it pass on gracefully ..

[fas42]

Well, all the clever people reading this should be able to tell me how to make my HP work again, by now  ... I'm waiting !!! ,

[Ralf11]

just tune it

[fas42]

Might actually need - shock, horror!! - reseating of connectors ... ... Nahhh!!

 

In the throes of a 12 (!!) hour (where does Windows get these crazy estimates from??) copying recovery of the disk data at the moment ...

[fas42]

The hard drive has a problem - it's partitioned into two volumes, and the primary one has gone ta ta - "Please format ...". But the drive is happily working, extracting the other volume.

 

Why did it corrupt? Because the drive surface has gone bad, or because the laptop sent 'nasty' signals to the drive?

[Ralf11]

because HDDs have a limited lifespan

[fas42]

Agree ... but I've been lucky over the years, and find it hard to recall ever having one go bad on me - it's always been something else.

 

I will go through the hoops, and try to resolve what is primarily at fault. The laptop was behaving a bit "funny" the previous day -  eg., an application process halted for no apparent reason; and a new version of a reliable utility refused to run, and no-one else seemed to have this problem.

[fas42]

Some good news ... the HP is back on line!

 

Did a full recovery of all the files, just in case - Recuva did its job nicely; then ran CHKDSK against the primary drive; errors found, corrected - all good! Drive back in, and all's well ...

 

But, did the corruption occur because of a hard shutdown, or some subtle glitch elsewhere in the hardware, still? Will take it carefully for a bit, keep a sharp eye on anything not exactly as it should be.

[fas42]

On 10/13/2018 at 10:54 AM, fas42 said:

The laptop was behaving a bit "funny" the previous day -  eg., an application process halted for no apparent reason; and a new version of a reliable utility refused to run, and no-one else seemed to have this problem.

 

Crazy stuff! That "utility" was Audacity 2.3.0, and I've been looking for an answer for a week or so - was suggested that a specific, empy folder be manually added to the installation - and lo and behold, the program emerged from behind the veils!

 

Talk about making systems robust ...

[fas42]

And, the latest Audacity is still 'bad' ... as good an example of step by step, as anything  else, .

 

In the meantime, until this is sorted, I'll have to drop back to version 2.2.2 - to get real things done ...

 

A side note: I hate things having a "bad feel" - which is why I react to people getting terribly technical in dealing with a situation, when there are obvious, glaring problems that cry out to be fixed first. Case in point: people  asking whether a corrected FR sounds "better" - I say, First sort out that terrible treble distortion - I can't hear past that!

[semente]

9 hours ago, fas42 said:

And, the latest Audacity is still 'bad' ... as good an example of step by step, as anything  else, .

 

In the meantime, until this is sorted, I'll have to drop back to version 2.2.2 - to get real things done ...

 

A side note: I hate things having a "bad feel" - which is why I react to people getting terribly technical in dealing with a situation, when there are obvious, glaring problems that cry out to be fixed first. Case in point: people  asking whether a corrected FR sounds "better" - I say, First sort out that terrible treble distortion - I can't hear past that!

 

Frank, I think you need new speakers... ?

[fas42]

12 hours ago, semente said:

 

Frank, I think you need new speakers... ?

 

Hopefully said in jest ... I suspect many people would be astounded how good really, really cheap speakers sound if driven properly - I gave up on speakers "solving things" decades ago; the main advantage that premium drivers, etc, give is that they should require far less conditioning from a cold start in the day to reveal low level detail well.

 

The current Sharp boombox speakers show how easy it is these days for big manufacturers to get raw components of decent quality to do the job at low cost. Even from immediate turn on in the morning, a heavy duty solo piano recording comes across very well - as contrasting with the poor standard often heard from audiophile setups.

 

 

[fas42]

Keeping an eye on what professional pilots are commenting on, in regard to the Lion Air plane crash, and there is a building up of a sense that the pilots were confronted with a situation where the plane went into an unstable mode, where it would have been exceedingly difficult to react correctly to what was going on. IOW, the plane was 'faulty', aided by inadequate design of the system - will be interesing to see how the investigation pans out ...