Play-Thru! is a little application that allows Macintosh computers equipped with sound recording hardware to play audio coming in to be recorded out the Macintosh’s own speaker. In other words, you can now throw away your stereo amplifier! Well, maybe not—I mean, the Macintosh speaker isn’t exactly a contender for the next audiophile sub-sub-sub-woofer, but it is nice to have music-’n-stuff while one is working with the old Mac.
As far as I know, only Macintosh LC’s and IIsi’s have the requisite hardware. You see, your sound recorder (you don’t have one of those third-party things, now, do you?) must support the play-through feature that went in with the new sound manager in System 6.0.7 and 7.0. If Play-Thru! puts up a box that goes something like “Sorry, but play-through couldn’t be set for the standard sound input device,” then you are outta luck. Of course, this means you must be using System 6.0.7 or later to use Play-Thru! (That is, you must be using System 6.0.7 or later to use Play-Thru! successfully; I mean, if you just want to keep it lying around and not doing anything, then you can use pretty much any System you want.)
Operation is really simple. Just open the Play-Thru! application to start playing through, and then crank up some audio source into the sound input port of your computer or whatever. Any audio the computer makes (such as game sounds, your system beep, or what-not) will be mixed with the audio coming in and will be played through the Macintosh’s speaker—it’s really neat. To turn play-through off, hold down the delete or backspace key as you open the Play-Thru! application.
Play-Thru! allows you to set the volume at which the incoming audio plays through your internal speaker. This setting is independent of the volume setting in the “Sound” control panel (which is for computer-generated sounds). To set the play-through volume, hold down the command (that’s the little clover-leaf-like, squiggle thingie) key as you open Play-Through! You’ll get a dialog box that will let you type in a volume from 0 to 7 (0 is off, 1 is the softest, and 7 is the loudest), and then you can click either “Set Volume” to set the play-through volume, or “Apply” to just hear what that volume sounds like. “Apply” is a good way to see (I mean hear) what each setting is like, as you can quickly try them all and stay in the dialog box. Play-Thru! will remember the setting so when you next run it that’s what the play-through volume will be set to. There’s also a “Cancel” button and an “About” button in the dialog, and these should be relatively self-explanatory. If they’re not, too bad.
By the way, Play-Thru! is about bursting with Balloon Help for you System 7 people. (You say you aren’t using System 7? I know, I know…) The application’s icon in the Finder has a summary of the keys to hold down when opening the application, and all of the items in the Set Volume dialog have their own balloons as well.
The best way to use Play-Thru! is to put it (or an alias of it) in your Startup Items folder. That way, whenever you turn on your machine Play-Thru! starts play-through, and your music can immediately spring forth without any human action other than hitting that power button. You System 6.0.x people can set Play-Thru! as the start-up application for the same effect; see your manuals (you still have them, right?) if you need help. Another good place for Play-Thru! is in your Apple menu. (Place Play-Thru! or an alias of it in your Apple Menu Items folder; System 6.0.x people will not be able to do this.) As a last resort, try your desktop.
The author of Play-Thru! (also known as “me”), Shawn Cokus, is a freshman in Mathematics/Computer Science at Carnegie-Mellon University, who may have to work inordinately hard now to maintain his “A” in Calculus and Economics after spending way too many hours reading Inside Macintosh VI to write this application.
Since I’m a starving (literally) college student with no money (look up CMU’s cost these last few years) I must ask that if you decide to keep Play-Thru!, please send $5 or so to my home address at:
Shawn Cokus
5261 Knolltop Terrace
Syracuse, NY 13215–1571
Alternatively, you can use my campus mailbox, but it will only be valid until May 7, 1992. The address is:
Shawn Cokus
Box 4880
5115 Margaret Morrison St.
Pittsburgh, PA 15213-3811
If you have comments, bug-reports, etc… please send them to either of the above snail-mail boxes or use my Internet e-mail address of sc5h+@andrew.cmu.edu.
Besides being an exercise in System 7-savvation, Play-Thru! was written to see just what paranoid error-checking is all about. Suffice it to say that you shouldn’t have any crashes; you’ll get nice, cryptic alert boxes instead!
The Play-Thru! application may not be modified in any way by any means.
The Play-Thru! documentation may not be modified in any way by any means.
The Play-Thru! application may not be distributed without this documentation under any conditions.
Permission is granted to freely reproduce the Play-Thru! application and this documentation, provided that the above conditions are met and no distribution fee is involved. Individuals or organizations wishing to include Play-Thru! in packages distributed for a fee must contact the author through one of the means listed above for prior permission.
The author is not responsible for any damages, direct or indirect, of any kind by the acquisition, storage, use, or distribution of this application or its documentation. The user acquires, stores, uses, and distributes the software and its documentation at his or her own risk. The storage, use, or distribution of the software or its documentation constitutes acceptance of the above terms.
