This line:
Serial.println("\x07"); //ascii bel
... when sent to PuTTY plays a sound, but when sent to the IDE serial monitor it prints a box.
Can the monitor be made to play the sound?
Monitor also doesn't honour the ascii BS backspace, x08.
If you send a BS to PuTTY the cursor does actually go back, leaving characters previously printed intact on its right, and subsequent print will overwrite the characters to the right of the backspaced cursor; serial monitor prints boxes for BS.
I wonder if these are settings anywhere?
So use PuTTY to open the serial port to the Arduino rather than the IDE. There is nothing special about the IDE's Serial Monitor - it is just a dumb terminal.
blh64:
So use PuTTY to open the serial port to the Arduino rather than the IDE.
If I hadn't been doing that, I wouldn't have been able to ask the question, would I?
I repeat the questions for those who may actually be able and inclined to answer:
coffeeBean:
Can the monitor be made to play the [BEL] sound?
coffeeBean:
I wonder if these [honouring BEL and BS] are settings anywhere?
Can the monitor be made to play the [BEL] sound?
No.
I wonder if these [honouring BEL and BS] are settings anywhere?
No.
blh64:
So use PuTTY to open the serial port to the Arduino rather than the IDE. There is nothing special about the IDE's Serial Monitor - it is just a dumb terminal.
Not quite true. It's indeed a dumb terminal but it does not interfere with uploads (as it's under control of the IDE) like the other terminal programs do (and tes, I understand that one can't blame the terminal program fir that).
@coffeeBean
It's a debugging tool, not a full fledged terminal program.
sterretje:
@coffeeBean
It's a debugging tool, not a full fledged terminal program.
That's true, and I know that, but it's irrelevant in the context of my questions.
Thanks to groundFungus for actually answering. All it took was a simple "no", see?
The answer, given in reply #2, was NO, but you failed to understand that. Perhaps we do need to dumb things down a bit.
coffeeBean:
That's true, and I know that, but it's irrelevant in the context of my questions.Thanks to groundFungus for actually answering. All it took was a simple "no", see?
The answer was given so I only added my thoughts 
In response to reply #7, coffeeBean sent me a personal message, mostly just foul language.
Evidently it can offer denigrating remarks, but not take them very well. Too much coffee?
In the past I have actually found it somewhat difficult to sound an alarm even from the command line. There seems to be no simple command to generate a "beep" or repetitive tone to signal the completion of another process. "echo ^G" for one, does not work.