Coaster 1.0 is freeware, though I'd like to hear from people who use this software. Simply send an email to the address mentioned below. Please indicate if you want to be notified by email on updates/bugfixes.
DISCLAIMER: The software "Coaster" is provided AS IS. The author does not take any responsibility for damage (financial/material/immaterial) or loss resulting out of the use of Coaster. Use this software completely at your own risk.
Using Coaster should be pretty straightforward: Set the input characteristics you want using the Popups and Checkboxes, hit record and that's it. When you are done recording, hit stop and then click Save, which prompts for the filename.
Input Source Settings
• Sound Input: This is the Sound Input Device you are using. You set this in the Sound Control Panel under the Sound Input options. Coaster always uses this default sound input device.
• Input Source: Some sound input devices provide several sources where the sound comes from. You can select here which source you want to use.
• Sample Rate: Choose the sample rate you want to use. If you intend to burn a CD from the files you are recording, choose 44100.
• Sample Size: Choose the number of bits a sample is made up of. If you intend to burn a CD from the files you are recording, choose 16.
• Channels: Select if you want to create Mono or Stereo files.
• Automatic Gain Control: Check if you want the sound input device to adjust the gain in a way that you always get maximum possible level without clipping. This is inappropriate for "audiophile" recording as soft passages of music will be raised in level and the resulting sound files are no longer a faithful reproduction of the input signal. So, if you intend to burn a CD from the files you are recording, turn this off.
• Play Thru: Here, you can set the Play-Thru level (in 7 steps on some Macs, on/off on others, e.g. G3s). If the slider is over the crossed out speaker, the Play-Thru function is off.
• Input Gain Sliders: Here, you set the input gain in a way that you record with maximum level, but no clipping. Some devices don't support setting gain for left and right channels independently or even worse, not at all; the slider(s) for the corresponding channel(s) will be dimmed and/or moved along with the left slider. To set up the best recording level, make use of the various display aids like Headroom and Clipping indication (see below). You see the factor by which the input signal gets boosted/attenuated before undergoing AD conversion below the sliders (0.5 … 1.5). Most Macintosh models allow only for few discrete steps here; this will be reflected by the numbers under the sliders accordingly.
• Link L•R: Check if you always want both channels to have the same input gain setting.
REMEMBER: Not all Macintosh models support all the setting options provided by Coaster. If your Mac does not support e.g. separate Gain settings for left and right channels, the right channel slider will be dimmed (and move along with the left one). This applies to other things (like Automatic Gain Control or Stereo recording) in the same manner: If an option is not supported by your hardware, the corresponding control will be dimmed, or some choices won't be available.
Recording Options
• Hold Clipping Indicator: If this is on, once there was a clipping, the clipping indicator will be on indefinitely. This helps in judging a recording if you don't have an eye on the clipping indicators all the way through the recording. To turn off the clipping indicator, click on Reset Clip. If this is off, the clipping indicator will indicate a clipping for about 1 second.
• Beep on Clipping: A horrible sound is played whenever a clipping occurs. This is handy if you want to set the input level not using the Input Gain sliders, but by adjusting the output level of your sound source, and cannot look at the computer screen at the same time. This way, you can "hear" if a clipping occurred.
• Clipping is <x> consecutive MAX samples: Set the number of consecutive samples of maximum level that should occur before you consider it clipping. The default setting is 3 samples.
• Automatic Recording: Coaster detects gaps in the audio material and either pauses automatically during these gaps or starts recording in a new file after such a gap. You can set the desired gap detection characteristics in a separate dialog that opens when you click the Settings… button (see below for a detailed descriptions of this dialog).
• Eliminate Clicks: When you select this option, Coaster modifies your audio files at the beginning and at the end in a way that it's always at a waverform zero crossing point where the recording "ends". This is handled independently for left and right channels.
• Destination for new Recordings: Using the Choose… button, you are presented a file selector box where you choose a folder where Coaster puts new recordings. Clicking the displayed folder name, its window is opened in the Finder.
• Creator Code for new files: Here, you can enter a Creator Code for all newly generated/recorded sound files. If you don't know the Creator of the application you want to open the sound files after recording, choose "Same As…" and open the application you want (you may also select a file that was generated by that application).
• The scissors icon: When you click this button while a recording is in progress, a new file is started at that moment. The transition should be seamless (however, only if Eliminate Clicks is OFF!), so you can splice the resulting files into one single big file afterwards without loosing a single sample!
Displays
• Level Meter: This is where the recording levels are displayed. Three colours help you in judging the recording level, and accurate level calibration adds to this. On top of each bar is the clipping indicator which lights up when a clipping occurs.
Below each bar is the headroom display. There ou can see how much db's are left until clipping occurs. Click on the headroom display box to reset the headroom metering.
Cmd-Click in level meter box to change headroom display from available dBs to maximum absolute level that occurred up to that time and back. This is useful for obtaining accurate values for parameter settings in the Automatic Recording Settings Dialog (see below).
• Elapsed: Tells you how long the recording currently is.
• Remaining: Tells you how much you can still record in the folder you chose for new recordings.
• Clip Count: Tells you how many clippings have occurred. To reset the counter, click the display box.
Automatic Recording Settings Dialog
All level settings can be made either in absolute sample values ("Absolute"), dezibels of attenuation, i.e. negative values ("dB") or in percentage of the available sample value range ("%").
All time settings can be made either in milliseconds ("ms") or in number of samples ("Samples").
Simply choose the desired setting method using the popups to the right of the value entry fields.
IMPORTANT: When switching between units, rounding of the values might occur!
• Auto-Pause/Threshold: If the value falls below this level for at least the time specified in Postroll, the corresponding part is recognized as "silence", the recording is paused and the desired Silence Action is executed.
• Auto-Pause/Postroll: Recording continues for the specified time even after the audio level has dropped below the Threshold. You can think of this time the minimum duration of silence you want to detect as such.
• Auto-Resume/Threshold: If the audio signal level rises above this value and Coaster is in recording paused mode, the recording continues automatically.
• Auto-Resume/Preroll: If the signal level rises above the Threshold value and recording continues, the specified duration of audio that lies BEFORE the point where the Threshold was reached is written into the current audio file before the now current signal. This is used to be able to safely detect real audio material by setting a relatively high Threshold value, but not to lose the important attack phase of the signal that actually lies BEFORE the point where the Threshold value was reached. Coaster provides an internal pre-recording buffer to accomplish this task. The size of this buffer is limited to about 3 seconds at 44.1KHz/16Bit/Stereo.
• Silence Action: Select what sould be done when Coaster detects silence (a gap) in the audio material. If you choose Pause Recording, Coaster simply halts/pauses the recording until the Auto-Resume/Threshold value is reached, when recording resumes. If you select Pause & Split File on Resume, Coaster pauses recording when it detects a gap, immediately creates a new file und when recording resumes, audio data is recorded into the new file.
TIP: The following values have proven to be quite useful for a 44.1kHz/16 Bit recording from a CD or DAT source: Auto-Pause/Threshold: 50 (abs), Auto-Pause/Postroll: 1000 (ms), Auto-Resume/Threshold: 220 (abs), Auto-Resume/Preroll: 120 (ms)
Keeping or Discarding a Recording
If you have finished a recording, you may wish to keep or discard it. If you wish to keep it, click Save and Coaster prompts you for the name of the recording. If you have generated several files (using e.g. the Automatic Recording feature), the name you provide here will be used for all files generated, suffixed by the number of sequence they were created in. The number consists of only one digit if fewer than 10 files have been created; it consists of two digits if more than 9 files have been generated (so you can always "sort by name" in the Finder and get the right creation sequence).
If you want to discard the recording, click Delete, which deletes all temporary files which have been created during the most recent recording process.
Keyboard Shortcuts in the Record Window
Cmd-T: Toggle Automatic Recording on/off
Cmd-K: Same as clicking "Split File Now!" button
Cmd-B: Toggling "Beep on Clip"
Cmd-H: Toggling "Hold Clipping"
Cmd-. : Same as clicking Stop button
Cmd-<Tab> or Cmd-F: Opens the recording destination folder in the Finder
Cmd-, : Same as clicking Pause button
Cmd-R: Same as clicking Record button
Cmd-E: Toggling Eliminate Clicks option
Cmd-click in level meter: Toggle between available dezibels and absolute maximum value occurred so far
<Return>: Same as clicking Save
<Esc>: Same as clicking Delete
Cmd-W: Close the Record Window
Why yet another Recording Utility?!?!
Because I have not found one that has all of the following key features that Coaster has:
• Runs on 68k Macs (requires processor Motorola 68020 or higher)
• Accurate level display in db.
• Catches EVERY clipping that occurs (even in background) by not relying on the Toolbox functions for determining the input signal level, but by scanning the complete input signal that gets written to disk.
• Can record in background extremely well by using variable-sized record buffers. If Coaster tells you that the disk or your Mac ist too slow, simply allocate a bigger memory partition to Coaster and try again. 5000K have served me well on a Q660AV (68040/25MHz) machine.
• Provides Headroom display.
• Sound feedback for clipping. New clipping shuts up playing sound and is not scheduled AFTER a currently playing sound.
• Records all settings in the application's Preferences file.
• Restores Sound Input Device settings to original values when closing the Record window or quitting.
• Splits files on the fly without losing a single sample
• It's free :-)
Bugs & Suggestions
If you have found any bugs or want to make suggestions, please contact me via Email at rothc@in.tum.de .
You can download the current version of Coaster from
<http://www.in.tum.de/~rothc/coaster.html>
Note: The given addresses might change around April 1999. Please check back for more information. If you want to be notified about address changes, please tell me your email address.
