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Sound Cards And Speakers

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PCQ Bureau
New Update

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.

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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

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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.

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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.

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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

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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?).

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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?

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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.

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