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Sound Cards And Speakers

The
internal speaker–the only PC sound source for quite
a long time, finally gave way in 1987 when the first
Adlib Music Synthesizer card was put in the market.
In1989 came the first SoundBlaster card from Creative
Labs, marrying the humble PC to affordable audio, and
what followed has been quite a revolution.

Multimedia today drives a
major chunk of PC demand. Although the SoundBlaster 16 is
the de facto audio standard for the potential
buyer, the market is full of choices ranging from Rs 500
to Rs 20,000 soundcards, with brands like Creative Labs,
Aztech, ESS, MediaMagic, Genius, and many others vying
for your attention.

Broadly speaking, there
are two ways in which sound is produced by the soundcard:
FM synthesis and Wavetable synthesis.

FM
synthesis

FM (Frequency Modulated)
synthesis (often called the grand daddy of sound
reproduction on PC) uses a method of electronically
modifying different frequencies produced by the FM chip
to output the required sound. The technique not only
allows for reproduction of traditional sounds, but also
completely new sounds. But real instruments sound
unrealistic and cannot be accurately reproduced using FM
synthesis. Even though the technology is quite old, it is
still supported and is required for SoundBlaster
compatibility.

Wavetable
synthesis

In sharp contrast to FM
synthesis, Wavetable synthesis allows for faithful and
accurate reproduction of real instrument sounds.
Digitized samples from real instruments are stored on an
on-board ROM chip (similar to recording wave files of
real instruments), and these are further modified in
real-time using a Digital Signal Processor to reproduce
the entire range of frequencies required.

Even if your current
soundcard doesn’t provide Wavetable synthesis,
there’s hope for you. You can upgrade by adding a
Waveblaster or compatible daughterboard from Creative
Labs, Yamaha, or Roland if your current card provides a
WaveBlaster upgrade connector. Alternatively, you can use
software-based synthesis programs like Wingroove or
Yamaha YXG-50, but these are quite slow and are often not
available across operating systems. All Wavetable
soundcards are not created equal. Since wavetable
synthesis uses samples of real instruments, the source
from where samples have been derived could make a big
difference to playback quality. AWE32 and AWE64
soundcards from Creative Labs use samples from EMU
synthesizers (used by Michael Jackson for his History
album). Other soundcards use samples from Roland, Yamaha,
and the like. Since these samples are stored on the
on-board ROM in the soundcard, the size of this ROM can
also make a big difference to the final effect that is
produced. Soundcards with Wavetable synthesis generally
have 1MB or more of on-board ROM, and some like the AWE32
and AWE64 allow you to add more memory so that you can
add more instruments and samples onto the card.

Polyphony is also an
important factor that determines how good the soundcard
sounds while playing MIDI files. It refers to the number
of sounds the soundcard can play at the same time. Cards
with 64-voice polyphony can playback 64 voices
(instruments) at the same time.

 

The
Audio Codec (AC) ’97 Specification

Recently,
Intel, Creative Labs, Yamaha, Analog Devices, and
National Semiconductor jointly proposed the Audio
Codec (AC)’97 specification (www.intel.com/pc-supp/platform/ac97/) that outlines a new
approach to provide low-cost but high-quality
sound on the PC. Unlike today’s soundcards
which use proprietary codecs and Digital Signal
Processor (DSP) chips, the internals of AC
’97-compliant audio circuitry will also be
transparent to the operating system and system
hardware.

Acoustic
physical modeling

One step ahead of
Wavetable synthesis, acoustic physical modeling increases
the quality of MIDI reproduction on the PC. It’s no
secret to musicians that sound which comes from a cello
behaves differently from that of a trumpet. Although
Wavetable synthesis excels in the accurate reproduction
of acoustic instruments, it does not allow for
true-to-life output as in a real instrument. With
physical modeling, a mathematical model of the musical
instrument is created. Sound is then reproduced by
calculating how the instrument’s physical properties
would shape the resulting sound using a series of
mathematical equations. Currently available with AWE64
Gold (called WaveGuide), this technology provides a new
direction to the future of multimedia on PC.

8-
and 16-bit, and integrated sound cards

The very first soundcards
like the original SoundBlaster, SoundBlaster Pro, and
compatible cards were 8-bit cards and could only playback
to a maximum of 22 kHz. The new 16-bit series of cards
like SoundBlaster 16 can record and playback up to 44.1
kHz. This higher range of frequencies allows for better
quality of sound recording and reproduction. Although
44.1 kHz is generally considered the standard, high-end
cards like Turtle Beach Monterey can playback samples
even at 48 kHz.

A new breed of cards
available today like Telemetry 32 from MediaMagic, MWAVE
from IBM, and PhoneBlaster from Creative Labs use
powerful programmable digital signal processors to
combine telephony and sound features onto one card. For a
little more price than a16-bit soundcard, these cards
answer the phone, work as a modem and fax, in addition to
being a regular soundcard. Although such cards are very
cost effective, upgradability could be a problem. If you
want to have a faster modem, you will have to change your
sound card also! Some of the cards also have problems
while doing two or more tasks concurrently, like
downloading a file and playing a wave file.

However, if you are short
on cash, these cards offer good value. Somewhere in the
future, you might see a multi-functional card which will
monitor phone calls, identify the caller using voice
recognition, and use voice synthesizing software to
answer (in your own voice?).

Full
duplex

Full duplexing allows the
soundcard to play and record simultaneously. This is
specifically used for Internet Telephony applications
like Freetel and Internet Phone. If the soundcard
doesn’t support Full Duplex, all your communications
with Internet Phone, etc, could end up like you are using
a walkie-talkie.

Plug-N-Pray?

Installing a soundcard was
equal to getting your teeth pulled till recently. I still
remember the time when I had to fight for my sound
card’s rights to interrupts, ports and DMA channels,
and then row through driver conflicts to achieve Nirvana.
But not today. Plug-n-Play (PnP) support in Win 95 today
helps us escape jumper nightmares. It often makes
installing the soundcard as simple as it sounds.

But beware, if you are not
using the standard operating systems recognized by the
soundcard vendor (like Win 95, NT, etc), you could have
problems with PnP. Operating systems like Linux support
only a few PnP devices. You would be better off buying an
old non-PnP card.

SoundBlaster
compatibility

SoundBlaster by Creative
Labs is the de facto standard for multimedia PCs
today. Soundcards from other manufacturers provide basic
SoundBlaster emulation in order to remain compatible with
whole lot of games, audio utilities, and other software.
SoundBlaster compatibility can be maintained quite easily
by using Yamaha OPL-3 compatible chipsets that are used
for FM synthesis. Although FM compatibility can be
ensured, it is difficult to emulate the now common
EMU8000 synthesizer chip (used in AWE series of
soundcards from Creative) for Wavetable synthesis.

So, should you buy a
SoundBlaster compatible card or an original SoundBlaster
card? Most of the time, the only reason you might like to
buy SoundBlaster compatible card is because of the price
(as mentioned earlier these cards are quite cheap and
often linger around the price tag of Rs 500..1500). But
if you are looking for availability of drivers for all
platforms or want to ensure compatibility with most of
the multimedia programs in existence today, you would be
much safer with the original SoundBlaster.

All sound cards available
today also have a standard set of interfaces like Line-in
(so that you can record from external sources like Tape,
etc), Line-out (for piping the output of your soundcard
to an amplified speaker or hi-fi system), Microphone-in,
Speaker-out, and a Joystick/MIDI port. If you plan to do
some professional MIDI recording, you would need to
purchase a MIDI cable/converter, of which one side would
fit into the game port of the card and the other on to
your MIDI keyboard.

Technologies are being
upgraded, and by next year we will have more options to
handle. So what’s in store? Multichannel surround
sound, higher sampling rates, PCI technology, real time
effects, and probably some new standards. And the day
isn’t far away when hi-fi systems could go obsolete.
Maybe one day I will become James Bond, huh? Who knows!

The
dream sound card

For now—SoundBlaster
AWE64 Gold (PC Quest December 1997) remains the
ultimate soundcard for desktop multimedia. A
comprehensive feature set and good quality sound makes
this card recommendable, both for home and professional
use.

The AWE series of
soundcards has always been one of the most popular
Wavetable boards in the market, and AWE64 Gold uses some
of the best technologies in existence today to offer good
quality MIDI and Wave playback with 3D sound. The card is
integrated with the new Vibra32D chipset, EMU8000
Wavetable synthesizer, and offers 64-voice polyphony.

WaveGuide technology using
Acoustic physical modeling helps in simulating the actual
behavior of sound as it emanates from musical
instruments. MIDI professionals would like 4 MB of
on-board RAM (expandable to 28 MB) that could be used to
add more sounds and instruments, and the SPDIF output
that allows for transfer of digital recordings to a DAT
or CD-Recorder without any audio quality deterioration.
Also included is Vienna SF studio, a powerful MIDI studio
for creating new MIDI samples, the complete suite of
SoundBlaster utilities, MIDI recording studio, and
WebPhone for Internet telephony.

This full duplex, PnP card
is obviously SoundBlaster compatible. It comes
with gold plated connectors, MIDI cables, and a
hands-free microphone.

Multimedia
speakers

Given the same soundcard,
your speakers determine the quality of sound
reproduction. Multimedia speakers, as they are often
called, are available in the market in prices ranging
from as low as Rs 400, and upwards. Speakers that carry
brand names tend to be expensive, but often are a safe
bet.

Speakers for use with
computer equipment need to be magnetically shielded so
that they don’t create interference with rest of the
equipment, and don’t pose any danger to magnetic
media like floppies placed near them. If your monitor
flickers when you keep speakers near it, then magnetic
shielding is missing from those speakers, and it is not a
good idea to keep such speakers near your computer.

The General MIDI
Standard

Almost all
soundcards in existence today adhere to the
General MIDI standard. If you plan to use your
soundcard for composition of music, look for
MPU-401 compatibility for input and output.

The General MIDI
standard provides for playback of 127
instruments, and there are quite a few extensions
of General MIDI standard of which the XG (from
Yamaha) and GS (from Roland) are the most known
ones. These extensions often provide better
control of effects like chorus, and extend the
number of instruments and sounds available with
General MIDI, often upto 300 and above. However,
you don’t need XG or GS for basic MIDI
playback or for extra MIDI sounds. With cards
like Turtle Beach Monterey and AWE64, you can add
more instruments and samples by using on-board
ROM.

 

Before you decide on
speakers, think on how you plan to use them, and consider
your room’s dimensions carefully. If your room is
small, then a speaker set with an output of 10..20 W
would be sufficient to give the volume you require. Also,
consider the size of the speakers and whether you can
accommodate them on your desktop or not. Often you can
attach speakers to the sides of your monitor to save
space. For optimal performance, keep the speakers away
from the wall, and if you are not sure about the
placement, try out different placements. Also, make sure
the speaker’s cords don’t cross power cords as
it could cause interference and hissing.

When buying a set of
speakers, you could look for built-in 3D or surround
sound amplified speakers. 3D sound speakers are a good
idea if your soundcard doesn’t provide 3D sound.
Some of the speakers from Altec also provide Dolby
Pro-Logic support. The final effect with 3D sound largely
depends on what you are playing, and it isn’t a good
idea to use 3D sound speakers if your soundcard already
provides 3D sound.

When buying speakers it is
best to buy a speaker which is self-powered and amplified
(if the speakers has an adapter or takes batteries, it is
powered). Amplification provided by the soundcard is
often not good enough to produce good quality sound.

In conventional speakers,
Wattage rating indicates the maximum output you can pump
into the speakers before they fry themselves. Most of the
computer speakers, however, are amplified, and here the
wattage rating indicates the maximum power the built-in
amplifier can produce. PMPO (Peak Momentary Power Output)
is generally meaningless in the world of audio because it
represents an instantaneous Wattage rating at only one
point of the amplifier cycle. What you should look for is
the RMS (Root Mean Square) rating, as it represents the
average output. Most computer speakers don’t carry
that rating, although many high-end hi-fi systems from
Sony and alike have started carrying the RMS rating.

So, how do you decide
which speakers are good for your soundcard? Your ears are
often the best judge, if you don’t have access to
state-of-the-art testing equipment. Play a CD-ROM with a
deep rich bass sound, preferably instrumental. I prefer
recordings by Yanni as it has a wide range of frequencies
and real instruments. Most of the low-end speakers have
problem in producing the low frequency 30 Hz bass tone,
and when listening keep the volumes at marginal levels.
Be careful if the speaker has high levels of distortion
and produces buzzing or rattling sound. My advice, if
possible ask for a demo or buy speakers on a money-back
policy. Asking a friend, who has similar speakers, also
will help you decide.

If you are short on cash
or have a good quality amplified or hi-fi system, you
could avoid the additional expense of buying a separate
speaker set and connect the output of your soundcard into
the input of the music system. However, don’t ever
connect the soundcard directly to the big speakers of
your hi-fi system, unless you want to fry your soundcard.
Also, make sure the hi-fi system speakers are not kept
near your computer equipment as they are not magnetically
shielded, and generally have huge magnets which could
mean instant loss of data from floppies kept near them!

For better bass, you can
add a subwoofer to your existing speaker system. Only
meant for bass effect (which means you can’t just
use a subwoofer alone, unless accompanied by a pair of
speakers), subwoofers, unlike the speakers can be placed
anywhere in your room.

And last but not the
least, sizes don’t really matter too much. If you
don’t believe me—hear a Bose speaker in action,
and you will know what I am talking about.

PCQ Bureau: