the Soundcard Input
It is important to get a good signal from
your soundcard, with the minimum of electronic noise. A VU meter can be
shown to give a sense of the signal strength while you view the tuning
graph. This will be visible on the right edge of the window, but you
can position it instead at the top (or you can hide it, but it is
generally useful to display). A good signal should show more than half
the height at the loudest volume.
Tuning Meister has a simple oscilloscope function
begun under Options | Waveform Graph.
This is useful for determining the quality of your soundcard's signal.
So if you can't get a proper tuning trace this mode might help you
discover certain problems. You can see whatever noise might be lurking
when there is no input signal, such as a 60-cycle hum or little blips
from other electronic interference. You might also check strong signals
for clipping (discussed in detail below). While this is often indicated
in the VU meter with a red
flag, some sound cards create clipping situations without going full
scale; in this situation Tuning Meister will not detect the clipping
and no red flag will show. Even more disastrously, some sound cards
invert signals that go
beyond full scale, and that will create major problems with the tuning
analysis. A good signal might look like this on the 'scope function.
A poor signal means the tuning function will struggle to decide
on the pitch; and the tuning trace will be very unfocused, broad and
You can "Pause" [press keyboard "P" most easily] the
display, just as with the tuning trace, if you want the scope trace to
freeze. [Resume with any other keypress].
Windows provides a Recording Control,
similar to the Volume Control which can be launched by double-clicking
on the speaker icon in the System Tray. However, the path to this
control is well-hidden (indeed, I had to call tech support to find it,
when I moved to W95 from the old W3.1). So to make it easy, the
Recording Control can be launched from Tuning Meister at Soundcard | Input Volume Control.
This Control is what
you use to select which physical lines coming into the soundcard are to
be read by the computer. These lines might include a microphone, a
cable (this is a signal that is amplified, such as from a microphone
pre-amp, or the output from your stereo), and lines hidden inside the
computer such as the output from the computer's CD player. So if you
are not getting the desired signal into Tuning Meister (nothing shows
up in its VU meter) then probably you need to select something
different in the Recording Control. For instance, you might wish to
analyze some CD performance. You will have to be sure that CD Player is
selected, or more commonly today, Stereo Mix (see further discussion
below). You have to keep an eye on the settings; sometimes they get
changed by another program, without your realizing it. For instance,
when you launch Skype it automatically (quite sensibly) selects the
microphone as input; if you were using Stereo Mix and returned to
TuningMeister expecting Stereo Mix you would have trouble, which might
not be immediately obvious since the microphone might pick up the
speaker out. So TuningMeister would tune, but it would probably not
give a strong result. Just keep these hidden stumbling blocks in mind.
In the Recording Control you will also adjust the
input volume so that it is
strong but not clipping (this means, that
the signal is too strong for the range of the soundcard, and the
waveform displays a flat top and/or bottom, as below).
A slight amount of clipping as below will not affect the tuning
accuracy, but will definitely cause distortion in a recorded
microphone inputs are almost all monophonic, so if you want a stereo
signal, it must come from Line-In.
Unfortunately, many new computers, especially
laptops, save a few pennies by not including a separate Line-In input.
They may show Line-In in the Recording Control, but it is mostly a
fake. It's a sad situation. There then will be no way to input an
outside stereo signal into the computer, without investing in an
external sound card. (Many devices are available that connect,
primarily with a USB plug).
The Recording and Volume controls reflect the
particular design of the mixer functions supplied with the soundcard,
and they vary somewhat from one computer to the next. Windows has no
standard format for them. The two main
differences I have found are that some mixers allow you to select only
one input line at a time, through a box labeled "Select",
while other mixers are set up to allow
inputs; ones you don't want are stopped by checking their corresponding
If you haven't used the Recording Control before, it
may not display all the mixer lines that are available that you want to
use. In that case, from Options |
Properties within the Recording Control you will encounter a
dialog listing all the available
controls. Check all the ones you wish shown. Some may not be of
interest such as telephone input and you can hide them for less clutter.
Some mixers offer
a control which adjusts the overall input volume (in the lower
image, the left-hand control), in addition to the separate volume
controls for each particular line. Perhaps it would have been better to
call it Master Recording or something like that.
In the controls
for the Santa Cruz soundcard, it might seem as if the possibility of
mixing inputs doesn't exist at all. But the selected control, Stereo Mix,
actually means the mix
of all the inputs but doesn't seem to give any way to control the
constituents of the mix itself. In this case the soundcard comes
own mixer applet, which contains that functionality. So if your
soundcard has its own special mixer program, that instead of the
Windows generic mixer should be your
primary way of controlling input. That mixer you will have to launch
directly yourself; TuningMeister won't know about it. And under some
operating systems this link to the mixer does not seem to work - again,
you are on your own.
With 16-bit data,
the usual mode of operation, [not many soundcards are less than that
these days], the oscilloscope
an automatic gain increase with quiet signals, which it indicates by
drawing the expanded signal in various colors. You will see several forms superimposed at
different magnifications. So
as the most sensitive trace, red, gets bigger, it gives way to a green,
then a blue trace, and finally black. [Illustrated below]. That way you
can see the shape
more easily. Simultaneously, the regular trace continues in
black. The red trace has 256 times the sensitivity of the black trace.
If I just showed the black trace, you could not see that was some noise
in the signal, affecting quiet input.
the noise in this image of my laptop's microphone input at rest,
much more obvious in the magnified [red] trace,
which comes from some
electronic interference affecting the sound card. You can not always
get rid of that noise, but a stronger signal will lessen
its effect on the
The noise has almost completely disappeared when I plug a (cheap
Radio Shack) external microphone into the computer. [You might not be
Now with a soft tone sung into the microphone.
As the tone gets
louder, it moves beyond the scale that the red trace can handle, so
Louder still and the
green trace disappears.
Finally, only the
black trace remains. If it gets somewhat louder than this, clipping
will be seen.
that this flexible changing scale is easily understood.
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