Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

MELJUN CORTES computer organization_lecture_chapter_18_sounds

37 views

Published on

MELJUN CORTES computer organization_lecture_chapter_18_sounds

Published in: Technology
  • Be the first to comment

  • Be the first to like this

MELJUN CORTES computer organization_lecture_chapter_18_sounds

  1. 1. Chapter 18 Sound MELJUN CORTESMELJUN CORTES
  2. 2. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Overview In this chapter, you will learn to Describe how sound works in a PC Select the appropriate sound card for a given scenario Install a sound card in a Windows system Troubleshoot problems that might arise with sound cards and speakers
  3. 3. How Sound Works in a PC
  4. 4. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound-Capture Basics  Four components for capturing and outputting sound 1. Sound card 2. Speakers 3. Microphone 4. Recording/Playback software
  5. 5. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound-Capture Basics Sampling—capturing sound Sampling rate is measured in cycles per second (KHz)  Low quality (11 KHz) to high quality (192 KHz) Doesn’t capture every nanosecond of sound Takes samples and extrapolates, or predicts, what the data is between samples  Dotted line—can you connect the dots?
  6. 6. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound-Capture Basics Sampling—capturing sound Bit depth—Number of characteristics of a particular sound (for each sample)  Amplitude (loudness)  Frequency (tone)  Timbre (qualities from different instruments)
  7. 7. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound-Capture Basics Waveforms are commonly sampled with either 8 or 16 bits per sample 8-bit stores 28 or 256 different characteristics 16-bit stores 216 or 65,536 different characteristics Tracks Monaural—one track Stereo—two tracks CD quality 44.1 KHz 16 bit depth
  8. 8. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Recorded Sound Formats Pulse code modulation (PCM) Developed for telephone calls Better known as the WAV format Large files  Four-minute song at 44.1 KHz and 16-bit stereo is greater than 40 MB Compressor/decompressor (CODEC) programs  Algorithms developed to compress sound files  MPEG-1 Layer 3 codec or MP3 is one example of a codec
  9. 9. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Playing Sounds Every sound card can play WAV files using sound player software Windows Media Player comes with Windows iTunes is Apple’s media program Many other good sound players are available
  10. 10. © 2007 The McGraw-Hill Companies, Inc. All rights reserved MIDI Musical Instrument Digital Interface MIDI file is a text file Contain a series of commands that describe What note to play How long to play it Which instruments to use Tiny in size compared to WAV files Beethoven’s Fifth Symphony is 78 MB as a WAV file and 60 KB as a MIDI file
  11. 11. © 2007 The McGraw-Hill Companies, Inc. All rights reserved MIDI  Sound cards play MIDI files using one of two technologies 1. FM synthesis • Strictly electronic—software says what to play 1. Wave table synthesis • Uses recorded sounds (WAV files) to start • Modifies characteristics of sounds to create amplitude, frequency, and timbre desired • Polyphony of card—how many instruments it can play at once (128 instruments is common)
  12. 12. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Other File Formats Over 100 sound formats Table lists just a few Acronym Description AAC Advanced Audio Coding—native format for Apple’s iTunes AIFF Audio Interchange File Format—popular with Macintosh computers ASX Microsoft Advanced Streaming Redirector AU Can be played in Windows, Sun, Next, UNIX and Macintosh OGG Vorbis format—open source codex RM RealMedia—audio, or audio and video WMA Windows Media Audio—proprietary
  13. 13. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Video Videos typically have sound built in Some common video formats are Acronym Description AVI Audio Video Interleave MPEG Moving Pictures Experts Group MOV QuickTime ASF Advanced Streaming Format RM Real Media WMV Windows Media Video DivX Often used for ripping audio and video Flash Used on YouTube
  14. 14. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Applications Many applications (especially games) play sounds Most use the standard WAV, MP3, or MIDI file formats
  15. 15. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Streaming Media Broadcast of data that is played on your computer and immediately discarded Internet radio stations Most popular players are  Windows Media Player  Winamp  Apple’s iTunes
  16. 16. CompTIA A+ Essentials Essentials Getting the Right Sound Card Getting the Right Sound Card
  17. 17. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound Cards A sound card typically has many built-in features Two separate processors (one for MIDI and one for the rest) Support chips for joysticks Recording capabilities MIDI support More Can be a separate sound card Often just a chip built in to the motherboard
  18. 18. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound Card Differences Sound cards differ in five basic areas: - Processor capabilities - Speaker support - Recording quality - Jacks - Extra features Processor handles communication between the application, OS, and CPU Low-end sound cards let your CPU do most of the work Better sound cards do most of the processing, which accelerates the sound process and provides better sound quality
  19. 19. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound Card Differences Speaker support Basic support—two speakers or headphones Better sound cards support five or more speakers Often have a subwoofer 5.1 means 5 speakers with 1 subwoofer Recording quality Signal-to-noise (S/N) ratio expressed in decibels Low end have S/N ratio of 30 to 50 decibels  Records artifacts (noise) when there is no actual noise High-end cards offer a 96 to 100+ S/N ratio
  20. 20. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound Card Differences Jacks Line In and Line Out converters enable the sound card to send and receive input and output from other devices The Line In connector runs to a Line Out or Aux connector on the back of a stereo receiving system Rear Out connects to the rear speakers for surround sound Analog/Digital Out for external digital connections Microphone & Joystick
  21. 21. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound Card Connections Main stereo speaker is blue Line out connector is green Microphone connector is pink
  22. 22. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Sound Card Differences Extra Features Almost all motherboards have built-in sound Extra goodies needed to entice buyers Digital output to integrate PC with home entertainment system DVD receiver Surround-sound speaker connections Breakout box adding ports to front of PC More
  23. 23. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Audio Cables To play audio CDs through your sound card requires a cable from your optical drive to the sound card Most optical drives come with an MPC2 audio cable for this purpose
  24. 24. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Speaker Standards Stereo Left and right 2.1 systems Pair of speakers called satellites and a subwoofer
  25. 25. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Surround-Sound Standards Dolby Digital Supports five channels plus subwoofer (5.1) Front right, front left, front center, rear left, rear right Digital Theatre System (DTS) Competing standard that also supports 5.1 Sony/Philips Digital Interface (S/PDIF) Uses single connector for entire 5.1 system
  26. 26. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Surround-Sound Standards DirectX provides applications, primarily games, with direct access to hardware Offers developers easy-to-use commands Easy to program sounds in the desired channel DirectSound3D (DS3D) Can place a sound anywhere in 3D space Known as positional audio Environmental audio extensions (EAX) Creative Labs’ response to DS3D
  27. 27. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Speaker Features Controls Volume controllers On/off switch Can be on speakers or on special box Headphone jack Some systems can automatically sense when plugged in
  28. 28. Installing a Sound Card in a Windows System
  29. 29. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Physical Installation Installs like any other PCI card Plug in the card Load the drivers Test Hardest part may be identifying where to plug in speakers Refer to documentation Typical stereo or 2.1 speaker system plugs into Speaker or Speaker 1 port Surround-sound speakers use single S/PDIF
  30. 30. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Physical Installation Basic steps Shut down your computer, unplug it, and open the case Find an open PCI slot and install card Connect the CD audio cable to the drive and the card
  31. 31. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Installing Drivers Let Windows install drivers If necessary/desired, use CD that came with sound card If installing a USB sound card Follow the cardinal rule for USB drivers: Install the USB driver before the USB device Verify driver is installed by checking Device Manager Test
  32. 32. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Configuration Applications Most sound card configurations can be done within Windows Use the Sounds and Audio Devices applet in Windows XP’s Control Panel Or Sounds and Multimedia in Windows 2000 Five tabs  Volume  Sounds  Audio  Voice  Hardware
  33. 33. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Proprietary Configuration Apps Many sound cards install proprietary software Adds access to other features that aren’t otherwise available Autosensing—allows hardware to be plugged in using different ports and the ports adjust  Plug microphone into speaker port and speaker port becomes a microphone port
  34. 34. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Installing Applications Some sound cards install extra software Goal is to provide user with extra free software These programs aren’t needed to use any of the features Intended to provide extra value for the purchase
  35. 35. © 2007 The McGraw-Hill Companies, Inc. All rights reserved IT Technician CompTIA A+ Technician Troubleshooting Sound
  36. 36. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Hardware Problems Volume Check physical controls Check software controls  Windows Volume controls Speakers Ensure they are turned on and getting good power Make sure they are plugged in Check for visual indicators that a sound is playing  Replace speakers if blown speakers suspected
  37. 37. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Configuration Problems First place to check: Device Manager Consider reinstalling driver Ensure the latest device drivers are installed Check the manufacturer’s Web site for updates Review the Sounds and Audio Devices applet settings
  38. 38. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Application Problems First, look for an error message Check the application’s support site Second, check the sound file Sound files might be corrupted Last, reinstall the application
  39. 39. © 2007 The McGraw-Hill Companies, Inc. All rights reserved Beyond A+ Sound card benchmarking PC performance issues may be related to your sound card Analyze your sound card with RightMark 3DSound from iXBT.Com/Digit-Life
  40. 40. © 2007 The McGraw-Hill Companies, Inc. All rights reserved

×