logging in or signing up Tasko Speech Lab: New DSP smtasko Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 348 Category: Education License: All Rights Reserved Like it (4) Dislike it (0) Added: September 18, 2009 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... By: savitakandgule (18 month(s) ago) good evening i need this ppt, which will be helpful for my projects Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript An Introduction to Digital Signal Recording : Copyright Tasko & Finan 2008 An Introduction to Digital Signal Recording Stephen Tasko Ph.D. CCC-SLP Western Michigan University Kalamazoo MI http://homepages.wmich.edu/~stasko Topics : Copyright Tasko & Finan 2008 Topics Why focus this talk on high quality sound recording? Sound recording 101 Available recording devices Why focus discussion on sound recording? : Copyright Tasko & Finan 2008 Why focus discussion on sound recording? High quality digital recordings can now be made with fairly common devices at relatively low costs In my view, as both a speech language pathologist and speech scientist, good sound recordings give the SLP the most “bang for the buck” What high quality digital sound recording offers? : Copyright Tasko & Finan 2008 What high quality digital sound recording offers? Provides a permanent archive of client behavior Can allow quick, easy access to samples to monitor client status Has face validity Potential for more objective baseline and follow up evaluation Can support and guide clinical decision making Can serve to streamline and standardize assessment approaches Allows an entrée into More quantitative instrumented analysis Database development for clinician directed research on outcomes Sound Recording 101 : Copyright Tasko & Finan 2008 Sound Recording 101 Tasko’s rating system : Copyright Tasko & Finan 2008 Tasko’s rating system Preferable Highly preferred Not recommended Strongly discouraged Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording microphone Pre-amplifier (maybe) Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier The quality of the recording is only as good as its weakest component! How does tape recording differ from digital recording? : Copyright Tasko & Finan 2008 How does tape recording differ from digital recording? Analog (tape) recording Acquires a continuously varying signal Digital recording Acquires a string of discrete numbers Slide 10: Copyright Tasko & Finan 2008 Analog (Continuous) Digital (Discrete) -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 Digital Recording : Copyright Tasko & Finan 2008 Digital Recording Since sound is converted to a string of numbers, two issues have an influence on recording accuracy/fidelity 1. How often does the device “grab” a number? Sampling rate/frequency 2. How much precision is used when number recording? Quantization level Slide 12: Copyright Tasko & Finan 2008 Sampling Rate High Low Sampling Theorem : Copyright Tasko & Finan 2008 Sampling Theorem If a band-limited signal is sampled at a rate that is at least twice as high as the highest frequency of interest in the signal, no information is lost and the original signal can be exactly reconstructed from the samples Sound Frequency ranges : Copyright Tasko & Finan 2008 Sound Frequency ranges Normal humans hearing 20 Hz – 20,000 Hz Human speech ~ 50 Hz – 8000 Hz Standard phone circuits ~ 300 - 3000 Hz Frequency Range for Speech : Copyright Tasko & Finan 2008 Frequency Range for Speech 1. For good audibility, our recordings must capture the whole frequency range for speech. 2. Sample rate/frequency must be at lead twice the highest frequency of interest (16000 Hz). Digital Devices: Common sample rates : Copyright Tasko & Finan 2008 Digital Devices: Common sample rates 5,562 Hz 11,025 Hz 22,050 Hz 44,100 Hz CD quality Captures range of hearing Problems associated with poor selection of sample rate : Copyright Tasko & Finan 2008 Loosing important parts of the “bandwidth” Possibility of “aliasing” Most sound cards have anti-aliasing filters Low-pass filters sound to prevent aliasing However, you will still have a restricted bandwidth TAKE-HOME MESSAGE DO NOT UNDERSAMPLE YOUR SIGNAL Problems associated with poor selection of sample rate http://www.dsptutor.freeuk.com/aliasing/AliasingDemo.html F= 7 KHz SF=16KHz F=7 KHz SF=8 KHz Quantization : Copyright Tasko & Finan 2008 Quantization Inches less precise millimeters more precise Slide 19: Copyright Tasko & Finan 2008 Quantization High Low Quantization : Copyright Tasko & Finan 2008 Quantization Expressed in “bits” ↑ bits ~ ↑ # of marks on the “ruler” = greater precision X bits/sample = 2x possible units of measure For example, 2 bit = 4 levels 4 bit = 16 levels 8 bit = 256 levels 12 bit=4096 levels 16 bit = 65536 levels http://www.cosc.canterbury.ac.nz/mukundan/covn/Quant.html Quantization : Copyright Tasko & Finan 2008 Quantization Expressed in “bits” ↑ bits ~ ↑ # of marks on the “ruler” = greater precision X bits/sample = 2x possible units of measure For example, 2 bit = 4 levels 4 bit = 16 levels 8 bit = 256 levels 12 bit=4096 levels 16 bit = 65536 levels Checking your own computer : Copyright Tasko & Finan 2008 Checking your own computer Sound Fidelity vs. File Size : Copyright Tasko & Finan 2008 Sound Fidelity vs. File Size Digital memory is relatively cheap Good client records are invaluable Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier Digital File formats : Copyright Tasko & Finan 2008 Digital File formats Mono vs. Stereo Alphabet Soup .wav .nsp .mp3 .mp4 .wma .dss .au etc, etc, etc Digital File formats : Copyright Tasko & Finan 2008 Digital File formats Uncompressed Formats (Lossless) All samples are retained What you record is what you get Most common format “.wav” (PCM) Compressed Formats algorithm used to reduce file size yet maintain good audibility Driven, in part, by music industry Common Formats .mp3, .wma, .dss Effect on speech samples is not well known Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier Slide 28: Copyright Tasko & Finan 2008 Microphones Matter!! What (I think) you need to know about microphone selection : Copyright Tasko & Finan 2008 What (I think) you need to know about microphone selection Type of microphone Underlying operation How it connects to other devices Pick up patterns Frequency Response Microphones: Common Types : Copyright Tasko & Finan 2008 Microphones: Common Types Handheld Built in to recorder Clip on/lavalier Head worn Underlying operation : Copyright Tasko & Finan 2008 Underlying operation Slide 32: Copyright Tasko & Finan 2008 Slide 33: Copyright Tasko & Finan 2008 Slide 34: Copyright Tasko & Finan 2008 Headset Microphone Placement : Copyright Tasko & Finan 2008 Headset Microphone Placement Microphone Frequency Response : Copyright Tasko & Finan 2008 Microphone Frequency Response What is a frequency response curve? Graph that shows how the microphone responds over a range of frequencies Look for a relatively flat line within the frequency range for speech Frequency Response Curve : Copyright Tasko & Finan 2008 Frequency Response Curve Speech Range To pre-amplify or not to pre-amplify : Copyright Tasko & Finan 2008 To pre-amplify or not to pre-amplify Great variation in size of signal coming from mics May need to amplify the mic signal so it is heard by the recording device Often Best mics put out small signals Cheapest mics put out largest signals A Tasko Seal of Approval : Copyright Tasko & Finan 2008 A Tasko Seal of Approval Audio-Technica ATM75 (without powerpack!! - cheaper) Features Condensor type Headworn Directional Acceptable frequency response Decent sized output signal amplification not typically necessary Can be purchased with a variety of connectors REASONABLY PRICED (~ $99) Audio Technica ATM75 : Copyright Tasko & Finan 2008 Audio Technica ATM75 http://www.soundprofessionals.com/cgi-bin/gold/item/ATM75-SP-NP Recording Issues : Copyright Tasko & Finan 2008 Recording Issues Keep mic-mouth distance relatively constant within and across recording sessions Setting your recording levels is very important You really want a device that monitors the recording level Apply the “Goldilocks” Rule : Copyright Tasko & Finan 2008 Apply the “Goldilocks” Rule Not too big and not too small, but juuuust right! That recording level is just tooooo low! : Copyright Tasko & Finan 2008 That recording level is just tooooo low! Environmental noise becomes an issue Does not take advantage of the precision of the recording device That recording level is just tooooo high! : Copyright Tasko & Finan 2008 That recording level is just tooooo high! Signal will be “clipped” resulting in distortion Truncates the largest amplitude components Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier A brief survey of digital recording devices : Copyright Tasko & Finan 2008 A brief survey of digital recording devices Personal Recording Devices Digital dictaphones iPods PDAs (Palms, Smartphones) “Professional” Grade Devices Digital equivalents to the pro-duty cassette recorders Devices developed primarily for music industry The PC (or Mac) Laptop Desktop Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Basic recording performance questions Are the sampling rate options appropriate for speech recording? Is the quantization rate appropriate for speech recording? Is the overall frequency response of the device acceptable for speech recording? Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Microphone/recording level related questions Can an external microphone be used? What kind of connectors are needed? Will you need a mic amplifier? Can recording levels be adjusted? Can recording levels be monitored? Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Data Storage/Transfer Questions What file format is used to save the data? Can it record in a lossless format? What is the recording capacity of the system with the preferred recording settings? Does it have only built in memory or can you use standard memory media (e.g. SD cards)? How easy is it to move the recordings off the device and onto a PC for archiving (i.e. USB)? Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Human Factors Questions Can you easily play back recordings? What is quality of device playback? Is it easy to use? Is it too big or small? … Personal Recording Devices : Copyright Tasko & Finan 2008 Personal Recording Devices Digital dictaphones iPods PDAs (Palms, Smartphones) Many have good specifications File format options can be quite limited Often have serious limitations regarding microphone/recording level flexibility Dictaphones : Copyright Tasko & Finan 2008 Dictaphones Other options: iPod : Copyright Tasko & Finan 2008 Other options: iPod Personal Recording Devices : Copyright Tasko & Finan 2008 Personal Recording Devices “Professional” Grade Devices : Copyright Tasko & Finan 2008 “Professional” Grade Devices Greater flexibility in all areas Minimize concerns about digitization specs Typically use a .wav (uncompressed) format Larger and sometimes bulky Can be quite expensive Good values if you look at devices designed for the music industry Professional Duty : Copyright Tasko & Finan 2008 Professional Duty Marantz PMD660 ~ $500 Professional Duty : Copyright Tasko & Finan 2008 Professional Duty Boss Micro BR ~ $230 Professional Duty : Copyright Tasko & Finan 2008 Professional Duty M-Audio Microtrack < $300 A Significant Disadvantage of Recording with Portable Devices : Copyright Tasko & Finan 2008 A Significant Disadvantage of Recording with Portable Devices ↑↑ Housekeeping duties Sound recording file management Naming files so you know what is in them Moving files from device or portable media to a more permanent archive (PC, CD) Finding software to replay the files you’ve acquired PC Based Recording : Copyright Tasko & Finan 2008 PC Based Recording Free (yes, free) software for recording/analyzing high quality speech signals : Copyright Tasko & Finan 2008 Free (yes, free) software for recording/analyzing high quality speech signals Speech Tool SFSWin (UCL Phonetics Lab) Alvin Wavesurfer Praat Audacity Issues with PC recording : Copyright Tasko & Finan 2008 Issues with PC recording Not all PC sound cards are identical Vast majority work perfectly well Occasional problems include Noise or static Shifts in recording baseline (does not affect how it sound) You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Tasko Speech Lab: New DSP smtasko Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 348 Category: Education License: All Rights Reserved Like it (4) Dislike it (0) Added: September 18, 2009 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... By: savitakandgule (18 month(s) ago) good evening i need this ppt, which will be helpful for my projects Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript An Introduction to Digital Signal Recording : Copyright Tasko & Finan 2008 An Introduction to Digital Signal Recording Stephen Tasko Ph.D. CCC-SLP Western Michigan University Kalamazoo MI http://homepages.wmich.edu/~stasko Topics : Copyright Tasko & Finan 2008 Topics Why focus this talk on high quality sound recording? Sound recording 101 Available recording devices Why focus discussion on sound recording? : Copyright Tasko & Finan 2008 Why focus discussion on sound recording? High quality digital recordings can now be made with fairly common devices at relatively low costs In my view, as both a speech language pathologist and speech scientist, good sound recordings give the SLP the most “bang for the buck” What high quality digital sound recording offers? : Copyright Tasko & Finan 2008 What high quality digital sound recording offers? Provides a permanent archive of client behavior Can allow quick, easy access to samples to monitor client status Has face validity Potential for more objective baseline and follow up evaluation Can support and guide clinical decision making Can serve to streamline and standardize assessment approaches Allows an entrée into More quantitative instrumented analysis Database development for clinician directed research on outcomes Sound Recording 101 : Copyright Tasko & Finan 2008 Sound Recording 101 Tasko’s rating system : Copyright Tasko & Finan 2008 Tasko’s rating system Preferable Highly preferred Not recommended Strongly discouraged Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording microphone Pre-amplifier (maybe) Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier The quality of the recording is only as good as its weakest component! How does tape recording differ from digital recording? : Copyright Tasko & Finan 2008 How does tape recording differ from digital recording? Analog (tape) recording Acquires a continuously varying signal Digital recording Acquires a string of discrete numbers Slide 10: Copyright Tasko & Finan 2008 Analog (Continuous) Digital (Discrete) -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 Digital Recording : Copyright Tasko & Finan 2008 Digital Recording Since sound is converted to a string of numbers, two issues have an influence on recording accuracy/fidelity 1. How often does the device “grab” a number? Sampling rate/frequency 2. How much precision is used when number recording? Quantization level Slide 12: Copyright Tasko & Finan 2008 Sampling Rate High Low Sampling Theorem : Copyright Tasko & Finan 2008 Sampling Theorem If a band-limited signal is sampled at a rate that is at least twice as high as the highest frequency of interest in the signal, no information is lost and the original signal can be exactly reconstructed from the samples Sound Frequency ranges : Copyright Tasko & Finan 2008 Sound Frequency ranges Normal humans hearing 20 Hz – 20,000 Hz Human speech ~ 50 Hz – 8000 Hz Standard phone circuits ~ 300 - 3000 Hz Frequency Range for Speech : Copyright Tasko & Finan 2008 Frequency Range for Speech 1. For good audibility, our recordings must capture the whole frequency range for speech. 2. Sample rate/frequency must be at lead twice the highest frequency of interest (16000 Hz). Digital Devices: Common sample rates : Copyright Tasko & Finan 2008 Digital Devices: Common sample rates 5,562 Hz 11,025 Hz 22,050 Hz 44,100 Hz CD quality Captures range of hearing Problems associated with poor selection of sample rate : Copyright Tasko & Finan 2008 Loosing important parts of the “bandwidth” Possibility of “aliasing” Most sound cards have anti-aliasing filters Low-pass filters sound to prevent aliasing However, you will still have a restricted bandwidth TAKE-HOME MESSAGE DO NOT UNDERSAMPLE YOUR SIGNAL Problems associated with poor selection of sample rate http://www.dsptutor.freeuk.com/aliasing/AliasingDemo.html F= 7 KHz SF=16KHz F=7 KHz SF=8 KHz Quantization : Copyright Tasko & Finan 2008 Quantization Inches less precise millimeters more precise Slide 19: Copyright Tasko & Finan 2008 Quantization High Low Quantization : Copyright Tasko & Finan 2008 Quantization Expressed in “bits” ↑ bits ~ ↑ # of marks on the “ruler” = greater precision X bits/sample = 2x possible units of measure For example, 2 bit = 4 levels 4 bit = 16 levels 8 bit = 256 levels 12 bit=4096 levels 16 bit = 65536 levels http://www.cosc.canterbury.ac.nz/mukundan/covn/Quant.html Quantization : Copyright Tasko & Finan 2008 Quantization Expressed in “bits” ↑ bits ~ ↑ # of marks on the “ruler” = greater precision X bits/sample = 2x possible units of measure For example, 2 bit = 4 levels 4 bit = 16 levels 8 bit = 256 levels 12 bit=4096 levels 16 bit = 65536 levels Checking your own computer : Copyright Tasko & Finan 2008 Checking your own computer Sound Fidelity vs. File Size : Copyright Tasko & Finan 2008 Sound Fidelity vs. File Size Digital memory is relatively cheap Good client records are invaluable Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier Digital File formats : Copyright Tasko & Finan 2008 Digital File formats Mono vs. Stereo Alphabet Soup .wav .nsp .mp3 .mp4 .wma .dss .au etc, etc, etc Digital File formats : Copyright Tasko & Finan 2008 Digital File formats Uncompressed Formats (Lossless) All samples are retained What you record is what you get Most common format “.wav” (PCM) Compressed Formats algorithm used to reduce file size yet maintain good audibility Driven, in part, by music industry Common Formats .mp3, .wma, .dss Effect on speech samples is not well known Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier Slide 28: Copyright Tasko & Finan 2008 Microphones Matter!! What (I think) you need to know about microphone selection : Copyright Tasko & Finan 2008 What (I think) you need to know about microphone selection Type of microphone Underlying operation How it connects to other devices Pick up patterns Frequency Response Microphones: Common Types : Copyright Tasko & Finan 2008 Microphones: Common Types Handheld Built in to recorder Clip on/lavalier Head worn Underlying operation : Copyright Tasko & Finan 2008 Underlying operation Slide 32: Copyright Tasko & Finan 2008 Slide 33: Copyright Tasko & Finan 2008 Slide 34: Copyright Tasko & Finan 2008 Headset Microphone Placement : Copyright Tasko & Finan 2008 Headset Microphone Placement Microphone Frequency Response : Copyright Tasko & Finan 2008 Microphone Frequency Response What is a frequency response curve? Graph that shows how the microphone responds over a range of frequencies Look for a relatively flat line within the frequency range for speech Frequency Response Curve : Copyright Tasko & Finan 2008 Frequency Response Curve Speech Range To pre-amplify or not to pre-amplify : Copyright Tasko & Finan 2008 To pre-amplify or not to pre-amplify Great variation in size of signal coming from mics May need to amplify the mic signal so it is heard by the recording device Often Best mics put out small signals Cheapest mics put out largest signals A Tasko Seal of Approval : Copyright Tasko & Finan 2008 A Tasko Seal of Approval Audio-Technica ATM75 (without powerpack!! - cheaper) Features Condensor type Headworn Directional Acceptable frequency response Decent sized output signal amplification not typically necessary Can be purchased with a variety of connectors REASONABLY PRICED (~ $99) Audio Technica ATM75 : Copyright Tasko & Finan 2008 Audio Technica ATM75 http://www.soundprofessionals.com/cgi-bin/gold/item/ATM75-SP-NP Recording Issues : Copyright Tasko & Finan 2008 Recording Issues Keep mic-mouth distance relatively constant within and across recording sessions Setting your recording levels is very important You really want a device that monitors the recording level Apply the “Goldilocks” Rule : Copyright Tasko & Finan 2008 Apply the “Goldilocks” Rule Not too big and not too small, but juuuust right! That recording level is just tooooo low! : Copyright Tasko & Finan 2008 That recording level is just tooooo low! Environmental noise becomes an issue Does not take advantage of the precision of the recording device That recording level is just tooooo high! : Copyright Tasko & Finan 2008 That recording level is just tooooo high! Signal will be “clipped” resulting in distortion Truncates the largest amplitude components Components of Sound Recording : Copyright Tasko & Finan 2008 Components of Sound Recording Microphone Digital Recording Device Digitization of sound Storing of sound as file Playback ability Amplifier-Speaker Headset +/- amplifier A brief survey of digital recording devices : Copyright Tasko & Finan 2008 A brief survey of digital recording devices Personal Recording Devices Digital dictaphones iPods PDAs (Palms, Smartphones) “Professional” Grade Devices Digital equivalents to the pro-duty cassette recorders Devices developed primarily for music industry The PC (or Mac) Laptop Desktop Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Basic recording performance questions Are the sampling rate options appropriate for speech recording? Is the quantization rate appropriate for speech recording? Is the overall frequency response of the device acceptable for speech recording? Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Microphone/recording level related questions Can an external microphone be used? What kind of connectors are needed? Will you need a mic amplifier? Can recording levels be adjusted? Can recording levels be monitored? Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Data Storage/Transfer Questions What file format is used to save the data? Can it record in a lossless format? What is the recording capacity of the system with the preferred recording settings? Does it have only built in memory or can you use standard memory media (e.g. SD cards)? How easy is it to move the recordings off the device and onto a PC for archiving (i.e. USB)? Questions to ask about portable recording devices : Copyright Tasko & Finan 2008 Questions to ask about portable recording devices Human Factors Questions Can you easily play back recordings? What is quality of device playback? Is it easy to use? Is it too big or small? … Personal Recording Devices : Copyright Tasko & Finan 2008 Personal Recording Devices Digital dictaphones iPods PDAs (Palms, Smartphones) Many have good specifications File format options can be quite limited Often have serious limitations regarding microphone/recording level flexibility Dictaphones : Copyright Tasko & Finan 2008 Dictaphones Other options: iPod : Copyright Tasko & Finan 2008 Other options: iPod Personal Recording Devices : Copyright Tasko & Finan 2008 Personal Recording Devices “Professional” Grade Devices : Copyright Tasko & Finan 2008 “Professional” Grade Devices Greater flexibility in all areas Minimize concerns about digitization specs Typically use a .wav (uncompressed) format Larger and sometimes bulky Can be quite expensive Good values if you look at devices designed for the music industry Professional Duty : Copyright Tasko & Finan 2008 Professional Duty Marantz PMD660 ~ $500 Professional Duty : Copyright Tasko & Finan 2008 Professional Duty Boss Micro BR ~ $230 Professional Duty : Copyright Tasko & Finan 2008 Professional Duty M-Audio Microtrack < $300 A Significant Disadvantage of Recording with Portable Devices : Copyright Tasko & Finan 2008 A Significant Disadvantage of Recording with Portable Devices ↑↑ Housekeeping duties Sound recording file management Naming files so you know what is in them Moving files from device or portable media to a more permanent archive (PC, CD) Finding software to replay the files you’ve acquired PC Based Recording : Copyright Tasko & Finan 2008 PC Based Recording Free (yes, free) software for recording/analyzing high quality speech signals : Copyright Tasko & Finan 2008 Free (yes, free) software for recording/analyzing high quality speech signals Speech Tool SFSWin (UCL Phonetics Lab) Alvin Wavesurfer Praat Audacity Issues with PC recording : Copyright Tasko & Finan 2008 Issues with PC recording Not all PC sound cards are identical Vast majority work perfectly well Occasional problems include Noise or static Shifts in recording baseline (does not affect how it sound)