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The disappearance of darkness

 
 
Me
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      05-09-2013
On 9/05/2013 11:24 a.m., Alan Browne wrote:
> On 2013.05.08 18:52 , Me wrote:
>>>

>> No, the precise reason why valve amps are preferred over solid state for
>> electric guitar amplification is not linearity at < X% THD level, but
>> the characteristic of distortion when the amplifier is (deliberately)
>> over-driven - past the point of signal clipping.

>
> Got it. But I look at amps from the POV of music playback, not
> point-of-performance. In that sense the sole advantage of a tube amp is
> the continuous transition. (Class A transistor amps too, I suppose, but
> they are rather out of vogue).
>
> I don't know how well tube amps are wrt to noise these days. I'll have
> to wander across the street to my richer neighbor and play with his
> system one day using some good CD's. (And CD is good enough for me).
>
> Every time I hear a tube amp I can hear a hum.
>
> On Stevie Ray Vaughn's last album, on Little Wing, the hum from the amps
> is audible. A credit to using the raw recordings, but irritating.
>

Yup - hum is pretty normal and probably exacerbated by high gain setting
from the preamp section, as well as (probably) the amps SRV would have
used probably would have had "tank" reverbs (old-fashioned springs
between two audio transducers - a sender and receiver - still in common
use today), and also IIRC SRV played a standard fender strat with single
coil pickups (as opposed to dual "humbucker" pickups) and wait there's
more - the standard guitar cable and amp input sockets are old style 2
wire (shielded) phono connector with unbalanced signal, even though
balanced signal has been pretty much standard (using TRS phono sockets
or xlr) for other instrument and microphone signal cables for a long
time, with the result being able to do much longer runs of cable, with
much less noise.

I'm using a small "tri-amped" active speaker system as a home hifi
system ATM. In this case, class D for subs and main drivers, class AB
amps for the HF drivers, connected through a small mixer by balanced
XLR. It is phenomenally loud in a domestic setting, "only" about 2000
watts, but claimed maximum SPL is approaching 130dB at 1 metre. At full
volume (only ever used for demo purposes and to /really/ get the
neighbours upset <G>) There's no hum I can hear, but a very faint hiss
which isn't coming from the power amp circuits but the mixer (if I turn
the master gain down, then the hiss disappears). Unlike old-style small
PAs, it sounds excellent at lower volume and the close listening
distances in a typical house. I put most of this down to DSP, with
digital x-over at a very high 28dB/octave, built in digital delay
between drivers to avoid phase difference issues, and pre-set DSP
correction of spectral non-linearity of speaker response. This is not
high-end, but relatively middle of the road equipment (Mackie), in the
same sort of market as JBL etc.
It is however pretty ugly and industrial. It is also a "hifi purist's"
worst nightmare - especially those who believe that small low powered
amps can faithfully reproduce rock music - as it was meant to be heard.

 
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J. Clarke
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      05-09-2013
In article <(E-Mail Removed)>,
http://www.velocityreviews.com/forums/(E-Mail Removed) says...
>
> "Tony Cooper" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)...
> > On Wed, 08 May 2013 14:14:44 -0400, PeterN
> > <(E-Mail Removed)> wrote:
> >
> >>On 5/8/2013 1:10 PM, nospam wrote:
> >>> In article <518a6438$0$10808$(E-Mail Removed)-secrets.com>, PeterN

> >
> > Typical of nospam not to understand that the preference is based on
> > the process and not the result. He must think that a woodworker who
> > lovingly makes a table in his workshop is someone who refuses to
> > accept new technology because he won't buy a mass produced table from
> > Rooms To Go.

>
> This might be true for something hand crafted with aesthetic qualities, like
> a table.
>
> It is not true for items with technical perfomance issues - like a car.
>
> Time was hand crafted cars like Rolls Royce, Bentley and Aston Martin were
> seen as the best. By the 1980's they had been overtaken (figuratively and
> lterally) by mass produced top end cars like BMW, Audi and Mercedes. All
> these grand marques are now owned by big makers and whilst the leather seats
> and wooden dash boards might still be made by loving craftsmen, the engines
> and running gear are made by engineers in factories.


It's rather sad that the job market has declined to the point where
engineers have to work on production lines, however you really need to
explain what underemployment has to do with product quality.
 
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PeterN
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      05-09-2013
On 5/8/2013 3:51 PM, R. Mark Clayton wrote:
> "Me" <(E-Mail Removed)> wrote in message
> news:kmddkj$1bv$(E-Mail Removed)...
>> On 8/05/2013 10:16 p.m., R. Mark Clayton wrote:
>>> "Alan Browne" <(E-Mail Removed)> wrote in message
>>> news(E-Mail Removed)...
>>>> On 2013.05.07 16:25 , Me wrote:
>>>>> On 8/05/2013 1:02 a.m., R. Mark Clayton wrote:
>>>>>
>>>>>>
>>>>>> There might be a bit of nostalgia for vinyl records and even some
>>>>>> misplaces
>>>>>> preference for valve amps, but I doubt many other than Kodak will
>>>>>> mourn the
>>>>>> passing of wet film.
>>>>>>
>>>>>>
>>>>> Some of the preference for valve amps isn't misplaced. They're still
>>>>> the standard for some instrument amplification (guitars).
>>>>> There's also a parallel there with film/digital photography, as digital
>>>>> sond processing is used in sound-processing in so-called "modelling
>>>>> amps" (solid state) to replicate the "tone" (non-linear response) of
>>>>> valve amps. It's a bit like using a "velvia" filter in photoshop etc,
>>>>> to replicate the look of film.
>>>>
>>>>
>>>> The sole advantage tube amps have over transistors is the continuous
>>>> smooth transition of -ve to +ve voltages through the signal range
>>>> whereas
>>>> transistors have a discontinuity near 0 volts (for both the "push"
>>>> transistor (+ve side) and "pull" (-ve side) of the output in a class B
>>>> amplifier).
>>>
>>> Doh! you normally bias transistors, so it doesn't go -10V to +10V, but
>>> +5V
>>> to +25V.
>>>
>>> Valve amps do demonstate tonality and high [thermal] noise.
>>>
>>> Transistors were adopted in amps (and much else) because they
>>> outperformed
>>> valves on linearity / distortion, frequency response, reliability, noise,
>>> size, energy consumption and last but by no means least cost.
>>>
>>> Example - a basic EF81 (AF valve) was over 1 retail in 1973, when they
>>> were
>>> still in mass production - that is about 11 ($16) today. Even now an
>>> equivalent transistor would cost less than a dollar and out perform it in
>>> every way.
>>>

>> Some still are in mass production - perhaps just not in the kind of volume
>> as 50 years ago, ie:
>> http://www.jj-electronic.com/
>> There are also makers in Russia and China.

>
> No doubt - quite a good design IIRC.
>
>>>
>>>

>> It's moved on a bit recently too, with class D amps setting efficiency
>> standards, increased efficiency means less heat, smaller size. For large
>> concert PA systems - this type of audio amp may be used these days:
>> http://www.powersoft-audio.com/en/pr...eries/k20.html
>> 2 x 9000w in a small rack mount unit, 12kg weight.
>> (but you can almost guarantee that the guitarist will still be using his
>> valve amp, miked in to the PA)

>
> My partner worried when I bought a Sony AV amp (7x100W) - note sure what she
> would make of 18kW!
>

I didn't know I had such pretensions. And I don't know what you mean by
inferior technology.


--
PeterN
 
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PeterN
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      05-09-2013
On 5/8/2013 4:05 PM, R. Mark Clayton wrote:
> "PeterN" <(E-Mail Removed)> wrote in message
> news:518aaa9f$0$10819$(E-Mail Removed)-secrets.com...
>> On 5/8/2013 2:33 PM, nospam wrote:
>>> In article <518a960c$0$10823$(E-Mail Removed)-secrets.com>, PeterN
>>> <(E-Mail Removed)> wrote:
>>>

> SNIP
>>>
>>> the kodachrome look or velvia look can be done in software. grainy b/w
>>> films can be done in software. whatever film you prefer can be done in
>>> software.
>>>

>>
>> Stop shape shifting.
>> You said: "the only people who prefer film are those who refuse to accept
>> new technology." I called you on it. Now when do you want to meet real
>> people who do not fit your classification.

>
> Peter is basically right. There may be a few niches left for film (X-rays
> for instance, but even then...), but essentially almost all who still use
> film do so because they are set in their ways or they have not got around to
> buying new equipment yet.
>
> Again, when I was a kid in the sixties I used to be able to tell which
> pictures in National Geographic were Kodachrome and which Ektachrome just by
> looking and this was after process colour printing. Even with the highest
> standards of professional shooting and production there was a big colour
> cast on both (slate grey / blue on the former; orangy red on the latter).
> Sure film has improved since then, but has now been completely overhauled by
> digital.
>

I seem to recall Ecktachrome as haveing the blueish cast, and Kodachrome
as being warmer. For that reason, and its higher ASA, I used Ektachrome
for my underwater photography.


> Similarly in the late 1980's I could tell when Signal Radio was playing CD's
> by ear as I drove along the M6 because the sound quality was so much better.
> This was despite the fact that Signal obviously had top quality vinyl decks,
> it had a radio segment and was playing in my relatively noisy car.
>
> On my home system it is easy to forget and leave the amp is on because the
> noise level is so low with no signal you just can't hear it. There would be
> [intrusive] audible hiss from a valve amp.
>
> People who think vinyl is better than CD, valves amps are better than
> transistor and since fairly recently film is better than digital are just
> deluding themselves.
>
> These are the same suckers who buy silver speaker leads and $100+ [even
> digital] interconnects...
>
>
>>
>> that is the sole issue.
>> --
>> PeterN

>
>



--
PeterN
 
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PeterN
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      05-09-2013
On 5/8/2013 5:02 PM, nospam wrote:
> In article <518aaa9f$0$10819$(E-Mail Removed)-secrets.com>, PeterN
> <(E-Mail Removed)> wrote:
>
>>>>>>> the only people who prefer film are those who refuse to accept new
>>>>>>> technology.
>>>>>>
>>>>>> I would be happy to introduce you to some who would easily demonstrate
>>>>>> the gross inaccuracy of your statement.
>>>>>
>>>>> go for it. i would be happy to convince them of their mistaken beliefs.
>>>>>
>>>>> there is absolutely nothing inaccurate about my statement. it can be
>>>>> proven. it is not a matter of opinion.
>>>>
>>>> When will you be in New York. Or perhaps Downeast in Maine?
>>>>
>>>> BTW Your statement was
>>>> "the only people who prefer film are those who refuse to accept new
>>>> technology."
>>>>
>>>> When you let me know who you are and when you are available, I will make
>>>> a proper introduction.
>>>>
>>>>> digital is better than film and has been for many years, and as time
>>>>> goes on, the difference will get bigger.
>>>>>
>>>>> digital has higher resolution, higher dynamic range, more accurate
>>>>> colour, usable at *much* higher isos, more consistent (no variation
>>>>> batch to batch), does not expire and does not need to be kept cold.
>>>>> it's also cheaper per photo and no need for noxious chemicals to get
>>>>> results.
>>>>
>>>> Not the issue - see above
>>>
>>> it's *exactly* the issue.
>>>
>>> the film luddites think there's something magical about film. there is
>>> not. all of its characteristics can be modeled digitally, whatever film
>>> it happens to be.
>>>
>>> the kodachrome look or velvia look can be done in software. grainy b/w
>>> films can be done in software. whatever film you prefer can be done in
>>> software.

>>
>> Stop shape shifting.
>> You said: "the only people who prefer film are those who refuse to
>> accept new technology." I called you on it.

>
> you did not call me on anything nor am i shape shifting.
>
>> Now when do you want to meet
>> real people who do not fit your classification.

>
> i have no immediate plans to go to new york. maybe photo plus next fall.
>

Naturally, your statement would be proven wrong.

>> that is the sole issue.

>
> your inability to understand basic english is the issue, along with
> being an argumentative twit.
>


That's typical of you. When proven wrong you shift to name calling.

BTW by most standards, the word "most" has a very well understood and
BASIC meaning.

--
PeterN
 
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PeterN
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      05-09-2013
On 5/8/2013 6:01 PM, Tony Cooper wrote:
> On Wed, 08 May 2013 14:14:44 -0400, PeterN
> <(E-Mail Removed)> wrote:
>
>> On 5/8/2013 1:10 PM, nospam wrote:
>>> In article <518a6438$0$10808$(E-Mail Removed)-secrets.com>, PeterN

>>
>> <snip>
>>
>>
>>>>> the only people who prefer film are those who refuse to accept new
>>>>> technology.
>>>>
>>>> I would be happy to introduce you to some who would easily demonstrate
>>>> the gross inaccuracy of your statement.
>>>
>>> go for it. i would be happy to convince them of their mistaken beliefs.
>>>
>>> there is absolutely nothing inaccurate about my statement. it can be
>>> proven. it is not a matter of opinion.

>>
>>
>> When will you be in New York. Or perhaps Downeast in Maine?
>>
>> BTW Your statement was
>> "the only people who prefer film are those who refuse to accept new
>> technology."
>>
>> When you let me know who you are and when you are available, I will make
>> a proper introduction.
>>
>>>
>>> digital is better than film and has been for many years, and as time
>>> goes on, the difference will get bigger.
>>>
>>> digital has higher resolution, higher dynamic range, more accurate
>>> colour, usable at *much* higher isos, more consistent (no variation
>>> batch to batch), does not expire and does not need to be kept cold.
>>> it's also cheaper per photo and no need for noxious chemicals to get
>>> results.

>>
>> Not the issue - see above

>
> Typical of nospam not to understand that the preference is based on
> the process and not the result. He must think that a woodworker who
> lovingly makes a table in his workshop is someone who refuses to
> accept new technology because he won't buy a mass produced table from
> Rooms To Go.
>


Wow you just hit a chord. I once made a hand inlaid chess table, out of
birch and maple. It took months. When my daughter was in grade school,
she wanted to play the cello. After renting one for the first year, I
picked up an old beat up cello that had been carelessly covered with
shellac, for $5. We spent a summer stripping the instrument to bare
wood, staining it, and hand finishing it with violin varnish. Her music
teacher commented that it was rare to see a beginning student playing
such a fine instrument, and that it was worth over a thousand dollars.
My original reason was so that my daughter would help finish the
instrument, therby having an investment in it. She kept her interest for
about seven years. But, I guess nospam would prefer a machine made
Chinese instrument.

--
PeterN
 
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nospam
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      05-09-2013
In article <kmeqgp$2ni$(E-Mail Removed)>, Doug McDonald
<(E-Mail Removed)> wrote:

> > the film luddites think there's something magical about film. there is
> > not. all of its characteristics can be modeled digitally, whatever film
> > it happens to be.
> >
> > the kodachrome look or velvia look can be done in software. grainy b/w
> > films can be done in software. whatever film you prefer can be done in
> > software.

>
> You may be right about film. I won't argue.
>
> But I will about B&W prints. There as aspects of silver ... not
> to even include platinum or palladium or gold ... that cannot be
> duplicated. Certain types of papers have reflection characteristics that
> cannot be duplicated without metals in the emulsion. Of course,
> digital images can be printed on those papers.


print the digital image on silver based paper, as you mentioned.

in fact, that's what photofinishing shops do. the negatives are scanned
and then digitally printed on photo paper.

don't tell the film luddites though. they'll probably have a fit.
 
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nospam
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      05-09-2013
In article <518b22f2$0$10806$(E-Mail Removed)-secrets.com>, PeterN
<(E-Mail Removed)> wrote:

> >>>>>>> the only people who prefer film are those who refuse to accept new
> >>>>>>> technology.
> >>>>>>
> >>>>>> I would be happy to introduce you to some who would easily demonstrate
> >>>>>> the gross inaccuracy of your statement.
> >>>>>
> >>>>> go for it. i would be happy to convince them of their mistaken beliefs.
> >>>>>
> >>>>> there is absolutely nothing inaccurate about my statement. it can be
> >>>>> proven. it is not a matter of opinion.
> >>>>
> >>>> When will you be in New York. Or perhaps Downeast in Maine?
> >>>>
> >>>> BTW Your statement was
> >>>> "the only people who prefer film are those who refuse to accept new
> >>>> technology."
> >>>>
> >>>> When you let me know who you are and when you are available, I will make
> >>>> a proper introduction.
> >>>>
> >>>>> digital is better than film and has been for many years, and as time
> >>>>> goes on, the difference will get bigger.
> >>>>>
> >>>>> digital has higher resolution, higher dynamic range, more accurate
> >>>>> colour, usable at *much* higher isos, more consistent (no variation
> >>>>> batch to batch), does not expire and does not need to be kept cold.
> >>>>> it's also cheaper per photo and no need for noxious chemicals to get
> >>>>> results.
> >>>>
> >>>> Not the issue - see above
> >>>
> >>> it's *exactly* the issue.
> >>>
> >>> the film luddites think there's something magical about film. there is
> >>> not. all of its characteristics can be modeled digitally, whatever film
> >>> it happens to be.
> >>>
> >>> the kodachrome look or velvia look can be done in software. grainy b/w
> >>> films can be done in software. whatever film you prefer can be done in
> >>> software.
> >>
> >> Stop shape shifting.
> >> You said: "the only people who prefer film are those who refuse to
> >> accept new technology." I called you on it.

> >
> > you did not call me on anything nor am i shape shifting.
> >
> >> Now when do you want to meet
> >> real people who do not fit your classification.

> >
> > i have no immediate plans to go to new york. maybe photo plus next fall.

>
> Naturally, your statement would be proven wrong.


that would be quite the feat, because for it to be wrong, everything we
know about sampling theory, semiconductor physics and electrical
engineering would be invalidated.

nevertheless, if your buddy really thinks he can prove it, then best he
take that proof to mit. it's an easy drive from new york.

> >> that is the sole issue.

> >
> > your inability to understand basic english is the issue, along with
> > being an argumentative twit.

>
> That's typical of you. When proven wrong you shift to name calling.


you haven't proven me wrong and you are talking out your ass.
 
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nospam
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      05-09-2013
In article <(E-Mail Removed)>, R. Mark Clayton
<(E-Mail Removed)> wrote:

> Indeed one of the more sensible Hi-Fi mags tested regular mains cable
> against a group of expensive speaker cables. Virtually no difference. I
> did use [cheap] chunky speaker cable for my mains, but at full pelt they can
> be carrying quite a lot of current (10A+).


i got my speaker cable at a hardware store. 14 gauge wire is 14 gauge
wire.

there's nothing special about 'audiophile cable.' it's the same stuff,
but with a nicer looking insulation and a significantly higher price.
 
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Chris Malcolm
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      05-09-2013
In rec.photo.digital.slr-systems Alan Browne <(E-Mail Removed)> wrote:
> On 2013.05.07 16:25 , Me wrote:
>> On 8/05/2013 1:02 a.m., R. Mark Clayton wrote:
>>>
>>> There might be a bit of nostalgia for vinyl records and even some
>>> misplaces
>>> preference for valve amps, but I doubt many other than Kodak will
>>> mourn the
>>> passing of wet film.
>>>

>> Some of the preference for valve amps isn't misplaced. They're still
>> the standard for some instrument amplification (guitars).
>> There's also a parallel there with film/digital photography, as digital
>> sond processing is used in sound-processing in so-called "modelling
>> amps" (solid state) to replicate the "tone" (non-linear response) of
>> valve amps. It's a bit like using a "velvia" filter in photoshop etc,
>> to replicate the look of film.


> The sole advantage tube amps have over transistors is the continuous
> smooth transition of -ve to +ve voltages through the signal range
> whereas transistors have a discontinuity near 0 volts (for both the
> "push" transistor (+ve side) and "pull" (-ve side) of the output in a
> class B amplifier).


That's not an inherent charcteristic difference between transistor and
tube amps, it's simply a difference in the way te amplifier is
designed, e.g. class A, B, etc.. Neither device inherently can make
the +ve to -ve transistion. Tube amps managed it by simply biassing
themselves high so that the zero signal point was handled half way up
its voltage range. In the earky days of transistor amps the devices
didn't have the power to do that, so they chose to switch between
devices, one handling the +ve side, the other the -ve.

But teansistors are now powerful enough to run in the smae mode as
tube amps, i.e. with the zero signal point biassed half way up their
voltage range. And for those who care there are transistor amps made
to that design.

> That discontinuity in transistor based circuits


or tube amps operating the same mode.

> is audible to about
> 1/1000th of a percent of listeners. IOW, even "audiophiles" <cough>
> with the best trained ears would fail to pick it out in an ABX test.


> Anything related to the "tone" can be done in analog or digital circuits
> - more so in processing.


There were more differences than that. When tube amps were pushed past
their limits the distortion started rising, but it did so gracefully
and slowly. Whereas transistor amps pushed past their limits move very
rapidly into higher levels of distortion, and also a kind of
distortion which has a harsher sound. Since the loudest music tends to
be when lots of instruments (or voices) are playing at once, this
difference was most obvious as a muddying of clarity in loud
orchestral or large choir passages. Those with keen ears could also
pick up it with instruments which had very large sharp transient peaks
in the attack of their notes, such as a piano.

--
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