Monday, December 13, 2010

How should the bass be presented?

There is no question of the bass sound reproduced
from our hifi system has always being in the mind's
eye of most learned audiophiles to be/ should be
taut/tight/tuneful/with correct amount of decay &
no overhang whatsoever. So far so good? So what's
the big deal about the bass sound, as long as the
above are fulfilled or nearly there?!


However, to the audiophile community there is
still the question of preferences clouding the
thoughts & making some adjustments to the much
subjective(presumably it is) taste of like and
dislikes! As there are audiophiles who will
listen to bookshelf speakers with very little bass
and probably will continue to do so all their life.
And there are others who must have a pair of
floorstander speaker for their sonic diets!
Yet another even smaller group of listeners
who will and can only listen to their music
with subwoofer or subwoofers augmenting
the low registers and may even be the
lowest of frequencies that we could humanly
tolerate!


So we have different tastes and different
preferences and variously different hearing
acumens and ability. How about getting the
bass to sound closer to what we find in real
life events? (Now you are talking!) I now
throw a question to readers : Should the
bass sound be tuned to be close to or like
those of real events? Yes, no?


No! You say! We can never get there!
Alright then, how about a little bit of
excitements to entice our sonic diet?
How about some "chest hitting" bass?
(Are you nuts?) No! Seriously, we can
if we are willing to come up with the molah!
Actually, we can that is if we really want
those earth shaking bass! There are lots
of expensive hi end subwoofers out there
to choose. Make a google and one will find
plenty of brand types!


That seems easy enough, right?! Now here
comes the difficult part! How do audiophiles
tune the bass to get the 'chest hitting' bass
and at the same time have that bass sound
to be a important part of the soundstage?
I will let our readers here ponder for a while
with this idea. Please provide your comments
if you think it could be done!

Saturday, December 11, 2010

A diy task: Refurbish a subwoofer unit






Though this task was performed and completed
in June 2010, it is only now that I could put
this as a blog entry( I mean diary entry)
The dismantle of the subwoofer was a nerve
wrecking event at the beginning, as most of the
circuits are placed at the bottom of the cabinet
and have to be removed in parts, but when I
got a hang of it, I picked up the momentum
to proceed at a faster pace. The several
minor tasks include removing dust from the
components, after I had removed the cover from
underneath the subwoofer unit as it's one
of down firing design. The unit a NEC
subwoofer of the 1970s period, definitely
needed a change of capacitors to the power
supply section, I have to decide if the
original specifications be changed to suit
the type of sound of today or retain the
same signature sound of that period.


Since this subwoofer is part of a pair
(I've 2 units of the same) and to be used
as a stereo pair after the refurbishment,
so I followed back the same component
change as the other earlier acquired
unit but previously used in a mono
configuration. The handiwork was pretty
tedious, as it required dexterity of both
hands, magnifying glasses, and a strong
light source to enable me to see what
I'm doing! And yes, even before the change
of the electronic components, the woofer
cones were worked on, the rubberised(not
rubber but of another material that akin
to rubber like feel) surrounds needed a
change, and my friend Uncle Chew a design
engineer supplied me with a glue that
do not harden with age, and one of several
methods to change the surround. I finally
incorporated some of his method with that
of my own, to get the job done.


The 12" driver I discovered was a JBL
driver with a pressed metal chassis and
not the cast iron chassis frame that JBL
enthusiasts liked so much. Anyway, after
the surround was replaced and double
checked for correct alignment, the new
electronic components were replaced and
the circuit assembly put back in place, and
left to stand for a short while before it's
incorporated into the multi subwoofer
system that I've been using all this while,
and then the final test, the powering up.
This is always the nervous part of any
redo of the system's component units!
The reality test!


All went well and the usual thoughts about
the unit to go thru the customary running in
for the new driver surround and electronic
components change, which I reckoned needed
a few hundred hours. Sure enough the sound
did change, but very subtle indeed! A couple
of months had passed since June! The sound
remained the same, more or less. So a simple
check on the tuning sufficed, and it's music
again! A word of caution though, those who
are diy challenged in this area, should not
attempt this without proper supervision from
the learned hifi & diy gurus.


Friday, December 3, 2010

R's Music System










If one has followed the evolution(or development if u like
to call it that) of friends' hifi system, one will be probably
be amazed as to how the change of equipments could
affect the sound so much! I have one such experience to
document in this diary entry. I've followed my friend Mr.R,
in my neighbourhood over a few years, to know this to be
true!


Then, the time of KEF floorstanders driven by Passlab
amplifications and Classe CD source and now, Marantz
sacd 1, Parasound preamp and parasound monoblocs
driving a pair of Proac 3.8 speakers; depicted a very
significant difference in the sound/music reproduction
of those 2 time periods! As I recalled the big differences
and gradual changes of the sound as the equipments
get some further 'running in' , have me anticipating the
possibility of much greater improvements of the the
overall sound presentations and even more enjoyable
listening sessions to come! From what I heard over
the recent past few weeks when the changes to the
sound of new replacement equipments started to be
more apparent, I have to dismiss the idea of a quick
writeup, but instead waited out to do a writeup till the
sound gets even better!!!


Now what I perceived of the sound presentation, was
centred around the keyword: control. That good control
all round, not superlative yet, maybe there will be more
surprises to come, that I may not know yet. Maybe the
gears could still show sign of greater improvements to
come, as I could find more differences with each visits.
signifcances of those room Pretty sure those room
treatments (to be detailed in part 2 of this writeup)
which were progressively put in place, contributed to
the comfortable sound of the system. One matter is
clear in my mind, room treatments do brings out more
of the music!


Mr.R being more of a music lover than a hifi enthusiast,
is clearly shown with his choice of music spinned for his
visitors. Very varied and nonetheless shows his love of
music from his very large & impressive collection of CD
based softwares of redbook CDs, SACDs and have
many a visitor salivating over his many CD boxsets!!!
And yes I know he also enjoys fine wines and good coffee.


Alright, you have to ask, and what did I listen to with every
listening sessions. You name it, Classicals, jazz,
progressive rocks, country and western, music from the
60s, 70s, 80s, and some 90s. Each of the listening
sessions, between an hour to sometimes 2 plus hours,
were made up of a good cross section of various music
genres. Almost always calling it a night followed with a
supper session too.


At the first ever listen session of the Parasound monoblocs,
I asked specifically for the replay of the Dream of the Opera
CD, followed by Fleetwood Mac's 'Dream' track, Tracy
Chapman's "Baby Can I Hold You', Diana Krell's 'Look of
Love', some Police tracks, some Karajan's work, Bob
Marley and even Tsai Chin. The content of the music
replayed, come as no surprise, good control at least as
much as the Proac 3.8 could take it! If one don't go for
that brute force test that is. The high, mid range & bass
were more than sufficient for a not so overly aged person
like myself. It will still take some much younger listeners
to provide their views of the overall sound, to know if
different age groups have listened to the same sound.


At subsequent listening sessions, the listen materials
were all different, still the system could hold the music
together and the overall sonic presentations still
provided those many enjoyable listening sessions and
we have always set the sound loudness at a comfortable
level for those many listening hours! And I am grateful to
have The Wise One and Village Boy to keep me
company during the many listening sessions and
contributing to the discussions over supper.




Wednesday, December 1, 2010

B's Vintage Setup










One sunday afternoon, blog master, Kenneth, Uncle Chew
and myself, visited a friend with some vintage gears(for the
purpose of this write up,only the gears in used were
mentioned) that we were not familiar with. The setup was
placed in the spacious living hall of the house, which
was just about in many of opinions to be generally suitable
for speakers of that size. However, I thought this could be
flexible and one has to listen to be very sure, though
general opinions point towards empirical experiences and
proven practical knowledge that big speakers should be
placed in large rooms.


The speakers, a model of infinity series the Q2, from the
late seventies period, and a sound typical of that time.The
speakers appeared to be in the first instance different from
modern day design. First the number of tweeters that were
on each speakers, 3 pieces of ribbon tweeters, front firing
to the listeners and 1 more firing from the back of each
speaker! Arranged in a vertical array with each piece
individually angled inwards to the middle between the
speakers, seemingly able to cater for several choices of
listening positions along a dividing line between the
speakers. Besides the ribbon tweeters there were 2 more
dome tweeters also firing front to the listeners and common
beliefs has it that the dome tweeters would work over a
lower frequency range from those of the ribbon tweeters
and probably into the midrange too, as indication has it,
there is a single midrange driver that could have
complimented the tweeter arrangement design.


A bigger woofer cone type 15 inch driver, one each to
each speaker cabinets, completed the arrangement of
drivers and tweeters combination. The cabinets in it's
original form and aged over the many years of different
ownerships, dark wood coloured and probably some
wood polish or wood oil may bring back the good look
to the wood veneer. A back firing port covered with a
speaker cloth indicates that the speaker placement
could make for careful choices and may influence
how the speakers may sound with different placements.


We did some test listens as the visit was a fact finding
visit which the owner kindly accomodated. We listened
to a jazz sampler courtesy of Interglobal music and the
'Dream of Opera' CD which I may have mentioned in the
write up of visits to other music lover's music room. Not
to confuse readers about how the music sounded, my
personal choice of descriptions will not be provided here,
as different persons in their music or hifi journey
conceived good sounding presentations to be utterly
different from each other. So the opening drum sound
of track 6 of the Dream of Opera cd will have different
meanings to different persons. So to some a drum
sound is just a drum sound, to some others who may
have moved on to be able to perceived the skin of the
drum and how that skin vibrate and how the subsequent
resonating low hz would sound like, and to some others
it may be again with some ever more slight differences,
and again there will be some who have not reached this
level and may not be able to perceived the sonics or
otherwise too subtle to be perceived yet or that the
perceptions of low frequencies may be a very personal
choice, and how low the low bass one wants may
dictate the choice of listening materials.


We have a choice of amplifications between a preamp
unit plus the Odyssey power amp and a vintage
Yamaha integrated amplifier CA2010. Both of which
we tried, and both sounded just as good. However we
unanimously preferred the vintage speakers with the
vintage amplifier as the colourations (called it distortion,
ifyo u like it) add to the flavour of the music for that
afternoon's listening session. It would probably have
been different at another listening sessions with
some other listening materials. As we listened to
some vocals besides some jazz and some chinese
music. We even tried listening at different listening
positions, middle of the hall and all the way to the
back wall, which we thought the presentations of
which to be different, depending on personal choices.


That afternoon we looked for a 'comfortable' music
presentation and a listening session that we can
call 'enjoyable' and not a loudness test, and hence
look into rearranging the speaker placement(the
owner asked us to do the placement for him
anyway) and looked at the choices of listening
spots. We did found one but it wasn't what the
owner would call his ideal choice. So we worked
out something he could like and suggested he
listen for a while to see if he will like it and could
listen over a long listen session.