
5th August - by Ozhan Atalay
22 Tips to Obtain Better Sound in a High End Audio System -
PART II
9. Grounding the Metals for Static Electricity; especially in
wet weather and in fully carpeted listening environments,
static electric become an issue. The carpet is charged with
static electric which can be passed through the electronic
equipments via the rack and/or via human touch. Static
electricity on the carpet is such powerful that when checked in
the morning before somebody walks on it, can be clearly seen by
simple tools sold in Radio Shack
In order to eliminate the effect, the loudspeaker stands and
the equipment racks should be connected to earth by a thin
wire. Moreover, the loudspeaker cables and interconnects should
be lifted away from the floor due to the same effect.
What benefits you may expect from this tweak is I don't know
why but less blurry and more tide lower bass.
10. Loudspeaker Distance from the Front Wall; Loudspeaker
producers generally recommend the distance of the speaker by
the front wall (the wall behind the speakers). Generally
speaking, the speaker should be located as far as possible from
the front wall. (Side walls as well) If they are so close to
the wall, bass standing waves will be reinforced (explained in
article five) and mid/treble band will be compressed due to
excessive bass energy.
Some audiophiles find the desired bass volume by placing them
closer to front wall which is not correct. One thing should be
considered that such bass increase is not due to the original
sound but it is the consequence by the room response called
coloration.
11. Auto former / Transformer Passive Line Stages; The new
developed technologies in hi-end industry made the
pre-amplifiers questionable.
Before end, the reason of a preamplifier was stipulated in four
basics;
a- To connect more then one unit together
b- Recording to tape from some sources
c- Low volume output and inverted polarity signal of turntables
(as the only source component)
d- Bass, treble adjustment requirements
Nowadays, CD, SACD units can provide 5-8 Volts of outputs which
are more than enough for the power amplifiers. Audiophiles are
not interested in tone adjustments but focused on simplicity
anymore. Dedicated phono stages are in common usage, hence, the
majority of the requirements are not valid anymore.
The main and the only basic job of a modern pre-amplifier is to
lower the volume level, not step it up !!
Just try to imagine a pure signal from a CD, or DAC through the
power amplifier, then cut this link, add four plugs, four
female plugs, a pair of interconnects, lots of resistors,
capacitors, tubes, transistors and all that stuff in the link.
How can you keep the signal purity and can you make something
better then its original !
An active line stage demolishes the neutrality and the purity
of the original sound. Such a corruption may not be so evident
in most of the lower resolution systems or disregarded by some
people on purposely. Every active line stage has its own
tonality and coloration. As a matter of fact, audiophiles
generally use line stages to balance their tonality problems in
systems. For instance, a tube line stage is used to calm down a
firm sounding solid state power amplifier or a treble rich line
stage is used to compensate the treble poor power amplifier and
vice versa. If this is the case in a system, fully natural line
stage and lack of coloration will not be regarded by the
audiophile.
Following me, the consideration should be to change the power
amplifier till finding the desired sound rather then playing
with pre-amplifier. In other words, to deal with the original
problem rather then trying to mask the problem.
It is almost in consensus that using a very simple volume pot
adds so much neutrality and purity to sound. But in such cases,
some other problems appear. A volume pot which is either a
potentiometer or a stepped alternator works with the resistance
principals. Every volume step adds different resistive path to
signal, thus lowers the volume. Due to the complexity of the
music signal ( 20 Hz-20 kHz), such a resistive load will act
like a barrier for different frequencies. For instance when
turning down the volume level, the treble is lowered and the
bass is condensed or when you increase the volume, mids are
excessive or vice versa. Not to forget to mention is the lack
of dynamic range as well. A line stage eliminates these
problems.
Due to these facts, volume control pots or analogue volume
controlled CDs can not be used stand alone as line stages
By the new technology, new auto former and transformer passive
line stages are developed for volume control.
Such units do not work with resistance principals and do not
add resistance to the signal path. The only resistance of such
amps is approximately 200 Ohms due to the cable in
windings.
Transformer passive line stages consist of two transformers,
one for the left channel, and one for the right. They have one
primary winding and multiple (12-24 steps) of secondary
windings. Their principal is to lover the volume by changing
the volts, rather then adding resistance. Up to my knowledge,
there are only three producers of such line stages. I used two
of them. Both of them are providing extra ordinary natural,
calm and undistorted sounds.
I heavily modified the Antique Sound Lab myself which is very
good product and quite cheap too, (don't underestimate its
price) but Audio Consulting's Silver Rock made of pure silver
is something else.
It should be also mentioned that such a passive line stages can
not be suitable for every system. In such a case, input
impedance of power amp should be driven directly by the output
stage of DAC or CD player. Input impedance of the power amp
should be as small as possible. The best way to learn this case
is to write the impedance values to producer and request
assistance prior to purchasing.
12. Good Tubes (NOS Tubes); is it logical to pay 100? to and
old tube while the new one costs 10 ? I believe it is. A good
tube can change the characteristics of a tube electronic as if
you replaced the entire unit. Nos tubes are not easy to find,
quite expensive but worthwhile to use. Especially the upper
frequency hiss is quite lower with Nos tubes.
13. Very Easy Polarity Finding Method; Generally speaking,
European (German) standard AC plugs do not have the signal
direction. US, UK, Swiss AC plugs have one way to connect to
AC, so + and - phases can not. So in such cases, it is not easy
to find out the correct polarity.
Electronic components can work properly regardless of the
polarity. Our televisions, refrigerators, bulbs, computers
everything. Why the AC polarity is quite important in Hi-Fi
!
Electricity arrives from (+) passes the electronic circuit and
departs from (-) Generally the mains current arrives in the
power supply of the unit first then reduced to desired voltage
by of the electronic circuits. At this case, mains is
automatically filtered by the power supply section. The
transformer of the power supply section behaves like isolation
transformer, input and output currents are physically
separated. If the polarity is not correct, the mains will
arrive to system directly from the back door and will carry all
the pollution like RFI/EMI into the unit. Due to the fact, it
is important to find out the correct polarity.
Most of the electronic' polarity is similar. If the unit has
detachable power cord and IEC kind of input, the right hole
should be the (+) mains when do you look at the plug front the
front face (as seen below)
Another simple method is to check the mains fuses. If the unit
is equipped with an exterior protection fuse, release the fuse
and check it by an electricity check pen while the unit was
connected to mains. It should be (+) signal. If not, reverse
the AC plug from the wall
14. Listening Volume Level; It is for sure nobody's business to
tell you that what the correct listening volume setting is.
Some audiophiles like very low listening level, some turn on
the volume till the windows are broken.
If the outcome is to achieve the ambiance of the recorded
venue, volume level should be adjusted accordingly but not more
or not less. This case is applicable to acoustic instruments
only but not to electronic music, jazz or disco etc.
What ever the listened record is, correct volume setting should
be the one which does not enlarge or shrink the original
instrument. Higher volumes may For instance a guitar should be
played with the original volume of a guitar by correct volume
setting. If volume level is increased, the body of the guitar
will became bigger in obsolete terms, on the other hands, full
body of a Mormon chorus will not be so realistic at low
volumes
15. Warming Up the Speakers and Cables Before Critical
Listening; Apart from the theory that "Solid state electronics
provide their best sound for a few minutes till the transistors
became warm." every single audio equipment needs a warm up
time. This time is at least 1/2 hour or even 1 hour in spite
the manufacturers recommend less. Up to my knowledge, the
reason behind this is the specifications of the resistors,
capacitors, tubes and other stuff vary if they are cold or
warm. Manufacturers make final settings when the units are
warm, otherwise they would play perfect for the first half an
hour and worse after warmed up.
That principal is applied by every audiophile for the
electronics but not always for the speakers and the cables.
Speakers are quite important since their passive components
should be warmed up such as crossover resistors. Their voice
coils should be warmed up as well. The cables are also
important. Warm up term may not eligible for the cables but the
cables should be run for sometime till their dielectrics are
charged.
As a result, the warming up time should be completed by playing
(may not be listening) the entire system.
16. Proper Loudspeaker Selection for Listening Room;
Loudspeaker should be selected in conjunction with the
listening room dimensions. Unfortunately the general tendency
in audiophiles particularly in US is "the bigger is better"
It is like some new starting skiers that choose the best ski
equipments prior to learning and facing with so many problems
afterwards.
Big loudspeakers are difficult to position, difficult to drive,
affected more from the room boundaries. If the speaker is
bigger for the room, excessive bass energy will diminish rest
of the sounds. The bigger speaker means bigger problems.
Driving big speakers requires challenge, experience, sources,
time and money.
Article Source: http://www.megamusicsite.com
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