PC Plus HelpDesk - issue 257
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This month, Paul Grosse gives you more
insight into some of the topics dealt with in HelpDesk.
From the pages of HelpDesk, we look at:
- Easy ASCII text;
- Extending ASCII text with outline images;
- Flexible logos with The GIMP;
- Installing The GIMP in Vista;
- No root GUI on Ubuntu;
- FTP to a machine without an FTP server;
- Clever printer server;
- Undoing file associations;
- GRUB - disc identities;
- GRUB - booting different OSes;
- 64Studio - Multimedia on your 64-bit PC;
- MIDI-USB hardware;
- SoundFonts; and,
- Rig-building tips.
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HelpDesk
Easy ASCII text
We've all seen text a the bottom of emails where
normal printing characters are used to produce larger
letters like so...
_____ _____ _____ _
| __ \ / ____| __ \| |
| |__) | | | |__) | |_ _ ___
| ___/| | | ___/| | | | / __|
| | | |____| | | | |_| \__ \
|_| \_____|_| |_|\__,_|___/
...and this can take some time - especially as you
fiddle around with it, getting it right. Of course, you
are limited to 80 characters (or less - once indenting
quotes have been done, you are often left with 78, then
76 [although the signature should be taken out
with the email program when it encounters a double-dash
at the beginning of a line followed by a space and then a
new line like so '-- ']) width so if you want to do
something with a lot of letters, you need to be careful
if you are going to get it all on.
(The one above uses the font 'big')
So instead of doing it by hand, you can install and
use one of the programs that will do this for you but if
it is just one or two designs you need, it is a waste of
time installing one. You are far better going for a
web-based service.
One such service will
create an ASCII text design for you, using just the
characters that you will find in emails - no fancy symbol
characters that won't reproduce properly - effectively
using a number of different font designs. The URL is http://www.network-science.de/ascii/.
Just type your text, select a font and click on the
'do it!' button.
If you want to see what your text looks like using all
of the fonts, choose '_all fonts with your text_'. You
can just highlight and copy the text, pasting it into
your email footer or wherever you want.
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Extending ASCII text with outline
images
Once you have your text just the way you want it,
there is nothing stopping you from adding your own
images.
This example is from OpenBSD - a free, open source,
hardened BSD that is well suited to hostile production
environments. Puffy the puffer fish was adopted to
represent the inclusion of the Blowfish encryption
algorithm for version 2.6 in 1999. We'd love to know who
'VK' is so that he/she can be credited with this
_
(_)
| .
. |L /| . _
_ . |\ _| \--+._/| . (_)
/ ||\| Y J ) / |/| ./
J |)'( | ` F`.'/ _
-<| F __ .-< (_)
| / .-'. `. /-. L___ _____ ____ _____ _____
J \ < \ | | O\|.-' _ / ___ \ | _ \ / ____| __ \
_J \ .- \/ O | | \ |F (_) / / / /___ ___ ____ | |_) | (___ | | | |
'-F -<_. \ .-' `-' L__ / / / / __ \/ _ \/ __ \| _ < \___ \| | | |
__J _ _. >-' )._. |-' / /__/ / /_/ / __/ / / /| |_) |____) | |__| |
`-|.' /_. \_| F \_____/ .___/\___/_/ /_/ |____/|_____/|_____/
/.- . _.< ======/ /======================================
/' /.' .' `\ /_/
/L /' |/ _.-'-\
/'J ___.---'\|
|\ .--' V | `. `
|/`. `-. `._)
/ .-.\
VK \ ( `\
`.\
All of the characters are easily accessible through
the keyboard - note the use of letter 'O' for the
reflection in the eyes. In this case, the characters used
represent the outline of the image but you can use other
characters if you want to represent half-tones.
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Flexible logos with The GIMP
Many image
editors will allow you to create logos but you have to
remember what you have done and how you did it for them
to be consistent enough to be usable for creating themes
for websites. You can use a DTP logo program but you will
probably find that it never produces anything that you
feel happy with
Some image processors have macros that you can use to
record actions and then play them back later - this
facility has been available for at least a decade with
one example being Micrographx Picture Publisher.
However, many macros are not particularly flexible and
you might well have to create new ones for different
situations such as font size and so on.
The GIMP, provides a set of macros that will produce
logos in different styles that you can size to make large
headers or small links. Each one allows you a number of
options such as font and various colours, along with any
other relevant parameters. You can get to the logos menu
by selecting 'Xtns', 'Script-Fu', 'Logos' and then you
can start experimenting.
Click on the image on the right to see the output and
a few tips.
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What to do...
This is how to do it.
In the main GIMP menu (on the form that has the
toolbox), click on 'Xtns', Script-Fu', 'Logos', 'Glossy'
(or whatever you want to try out).
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This is one of the more extensive dialogue
boxes - many of them are a lot simpler than this.At
the top, you can type in (or paste in) any text you want
(assuming that the characters you are using are in the
font you are going to use).
Next, you have the font size (in pixels) and below
that, the font itself. Click on this button and a pop-up
window appears, allowing you to select a different font.
These three controls are pretty standard amongst these
dialogue boxes.
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Next, you have the blend gradients for the
text and outline along with a few other options.If you
click on the gradient button (top-right), the gradient
selection dialogue box appears.
You can do with this what you would normally - select
one or edit/create one - clicking on the close button
when you have finished.
Below this, you will find the option to reverse the
gradient and then the blend gradient for the outline,
along with the option to reverse that and then how big
the outline should be.
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Next, you can select a background colour -
again, by clicking on the button.This time, the colour
selection dialogue box opens up with all of its usual
functions and options.
Clicking on 'OK' closes it.
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Following that, there are three patterns to
choose.Again, click on the browse button to display
the pattern selection dialogue box.
Once you have what you want, click on 'Close'.
Below that there are various options regarding what
you can put where and finally at the bottom, you have the
options of including a drop shadow, along with the x and
y offsets.
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Finally, click on 'OK' and your logo will be
produced.
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Note that in the layers dialogue box, you
can see that your image is still in layers.You can
select a layer and drag a colour into it or even a
pattern.
You might find that some layers will overwrite
completely if you do this (click on the image window and
press [Ctrl][Z] to undo it) and others will work out
okay.
Also, you can remove the background layer (in the
layers dialogue, right-click on the layer and then select
'Delete Layer') to make the logo transparent and then
make it into one layer (right-click as before and then
select 'Merge Visible Layers' then select 'Expand as
necessary' and click 'OK').
You can then save this as a PNG file or some other
format that supports half-tone transparency.
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This is the sort of thing you can get by
messing around, dragging patterns into the image.Once
you have something that you like that you can test at
different sizes, make a note of the parameters you used
(from the dialogue box) and then make your logo/style
sets for your web site.
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Installing The GIMP in Vista
Some people have been
saying that the GIMP hangs during first boot when it
starts looking for fonts the first time that it is run in
Windows Vista.
Certainly, it does appear to grind to a halt but this
only happens for the first time and is only a minute or
so (depending upon the speed of your machine, number of
fonts and so on).
In Vista, the fonts are in a different location to
other versions of Windows so The GIMP searches for them
(and finds them).
All you have to do is wait and once it has finished
doing this, it doesn't have to do it again because it now
knows where they all are.
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No root GUI on Ubuntu
It is possible to run
a system without a root GUI - this is something that is
done with Ubuntu.
Ubuntu doesn't allow users to log on as root and all
normal activities are performed as an unprivileged user.
As a GUI user wanting to do something as a super user,
you have to supply your regular password to do this when
prompted.
In fact, root is not permitted to open a GUI session.
This way, ordinary users have an easier time of coping
with security but without the risk of being permitted to
log on as root and then go browsing on the Internet and
opening up the machine to whatever anybody wants to throw
at them.
By having only one password to remember - the one that
they use all of the time any way - they will not be
locked out by forgetting it.
If a user does need to use the command line,
they can type 'sudo [command]' or, if they need an
interactive shell, they can type 'sudo -i'. The
disadvantage is, of course, that there is only one
password.
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FTP to a machine without an FTP
server
Sometimes, you need to use ftp or its secure
equivalent but the machine you want to log into has no
such server although you can log onto it.
This
problem, though, is not as difficult as it might at first
seem.
All you need to do is install an ftp server on your
own machine. You should have at least one included in
your distribution and they are fairly easy to configure -
vsftpd is a good one and the vsftpd.conf file is fairly
well explained.
Being your own machine, you have the final say on what
goes on it and what doesn't so you can install your own
ftp server and adjust your firewall accordingly.
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Next, log into the remote machine using ssh
(or telnet if that is what you use) and then ftp back to
your machine.In the diagram above, the command for the
telnet/ssh is in blue as you can see with the command
line for paul@obsidian, 'ssh'ing into 'zircon.
Next, when in zircon, ftp back out to your computer -
this is in green as is the command line for zircon so you
can see that from paul@zircon, I'm 'ftp'ing back to
obsidian.
Finally, remember that when you 'put' a file, you are
transferring it to your machine from the remote and vice
versa with 'get'.
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Clever printer server
Using a printer server like the one on the right, you
can convert a Centronics-interface printer into a network
printer. You can also get these with a 25 pin D series
connector socket as well so if your printer has one of
these instead of a Centronics interface, you can use one
of those instead (or just use one any way as normal
printer leads are 25 pin D series connector to
Centronics).
With such a printer server, there are a few things to
configure but once they are up and running, there is
little that can go wrong.
However, if your printer prints text all right but
won't print graphics properly - adding extra characters
at the beginning of lines that it then messes up - you
might have to tweak the configuration a little.
Especially if your printer worked all right when plugged
directly into the computer.
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One feature these servers have is to convert
a new line character ('LF') to a carriage-return/new-line
pair ('CRLF') which effectively makes the carriage return
to the left and the paper to feed by one line. Think
teleprinter or typewriter here.This is fine for
printing text but with graphics, it is a completely
different issue.
Graphics usually consist of a special code telling the
printer details such as: the length of the following
graphics string; the physical horizontal and vertical
space required for each pixel; the colour depth; and, so
on, followed by the graphics codes which have the range
0..255 (or 0x00 to 0xFF). This range includes the code
for a linefeed.
As a result of this, each time the server sees the
code for an LF (10 or 0x0A), it inserts a 'CR' (13 or
0x0D thus making a 0x0A into a 0x0D0A or 0x0A0D which is
two bytes instead of one), shifting all of the other
codes along by one. As a result, the last character(s)
meant for graphics end(s) up being printed as a character
for each 'CR' inserted as it appears no longer within the
graphics string.
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The solution is to log onto the printer
server's web page. On one of the pages - usually 'Logical
Printers' or similar (see the screenshots on the right
and above-right for two different examples that contain
essentially the same information) - you should find an
option to 'Convert LF to CR/LF'.Make sure that this is
unchecked and save it - you might have to switch the
server off and on again for this to take effect.
Your printer should now work as well as when it was
plugged directly into the computer.
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Undoing file associations
Opening files with a mouse click is easy and adding a
file association is almost as easy but make a mistake and
you need to know about undoing file associations.
If you right-clicked on an image file on a network
share and selected 'Open With', 'Other' and then selected
The GIMP (or any other program for that matter) and
checked the 'remember' box, you might have problems later
on because following that, each time you click on any
directory to open it up, it will try to open up The GIMP
and it, in turn, will give you an error message.
The problem is that with a network share (certainly
for SMB), you managed to associate an inode with the
GIMP.
However, you can
solve this by opening up 'Control Centre (Configure the
Desktop)' and then selecting 'KDE Components' and 'File
Associations'.
In the File Associations pane on the right, expand the
'inode' section of the tree by clicking on the '+'.
Click on 'Directory' and a further section will open
on the right of that.
On the 'Application Preference Order' list, click on
the GIMP and then on the 'Remove' button on the right.
This will remove the GIMP from the list.
Next, click on 'system_directory' and if it is there,
remove it from that list in the same way.
Once you have done this, you can also work your way
through the image types as well while you are at it. If
you mostly want to view jpeg and png images with, say,
Gwenview, instead of edit them, you can click on those
types, click on the programs in the list on the right and
prioritise them with the move buttons.
When you have finished, click on 'Apply' and you can
use your account again.
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GRUB - disc identities
Grub needs to be able to boot any operating system,
whether it is Linux, Solaris, BSD or Windows. This means
that it has to make sense of some very different ways of
looking at your system's hard drives and their
partitions. Each OS has its own way of looking at hard
drive space:
- Linux uses hda for the first drive with hda1
being the first partition, hda2 being the second
and so on with hdb being the second drive;
- Solaris uses slices with names like 'c0d0s7'
(channel 0, disc 0 (master), slice 7);
- OpenBSD uses a sliced partition with names like
'wd0a' (disc 0, partition 'a'); and,
- Windows names each partition, regardless of
drive, from 'C:' upwards.
Grub has to make sense of all of these - a thankless
task.
One problem you can have is if you put several OSes
onto one system. Naturally, you want to be able to boot
into each one from a boot menu and this is where GRUB
comes into it.
First of all, let's look at two physical system
configurations.
'Normal'
purchased system with 1 HDD
normal use |
Custom-built
system with 3 HDDs
disc-burning |
| Channel |
0 |
0 |
1 |
1 |
| Master/Slave |
M |
S |
M |
S |
| Linux designation
(/dev/...) |
hda |
hdb |
hdc |
hdd |
| Solaris designation
(/dev/dsk/...) |
c0d0 |
c0d1 |
c1d0 |
c1d1 |
| Use |
HDD |
|
Opt |
|
|
| Channel |
0 |
0 |
1 |
1 |
| Master/Slave |
M |
S |
M |
S |
| Linux designation
(/dev/...) |
hda |
hdb |
hdc |
hdd |
| Solaris designation
(/dev/dsk/...) |
c0d0 |
c0d1 |
c1d0 |
c1d1 |
| Use |
HDD |
Opt |
HDD |
HDD |
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The normal system is what you would get if you went
and bought one from a shop - it has one HDD and, of
course, it makes sense to have both the optical drive and
the HDD as masters on different channels. That way, if
you are burning a CD or DVD - exercises where redundancy
in channel bandwidth capability are essential - the data
flows better through the system.
The custom built system is what you might end up with
if you built one yourself using three HDDs. The first HDD
(master on channel 0) has the OS(es) on it and is used by
the system to run the system - there is little traffic
there once the system is up and running, apart from log
files and other stuff that is more intermittent and not
likely to interfere with CD or DVD burning. Another
consideration is that the main data storage should be on
a different channel to the optical drive. The optical
drive only occupies one slot so it makes sense to have
that on the remaining slot on channel 0 and have a data
drive or two on channel 1 so that either you have one HDD
there and can expand it or, have two to start with -
either way, you are not going to have to move your
optical drive.
So, there goes the myth that the optical drive is
always hdc in Linux.
Grub has to make sense of all of this so it makes the
first HDD the first drive, the second HDD the second
drive and so on. The count starts with zero so now, our
mapping looks like this...
'Normal'
purchased system with 1 HDD
normal use |
Custom-built
system with 3 HDDs
disc-burning |
| Channel |
0 |
0 |
1 |
1 |
| Master/Slave |
M |
S |
M |
S |
| Linux designation
(/dev/...) |
hda |
hdb |
hdc |
hdd |
| Solaris designation
(/dev/dsk/...) |
c0d0 |
c0d1 |
c1d0 |
c1d1 |
| Use |
HDD |
|
Opt |
|
| Grub disc designation |
hd0 |
|
|
|
|
| Channel |
0 |
0 |
1 |
1 |
| Master/Slave |
M |
S |
M |
S |
| Linux designation
(/dev/...) |
hda |
hdb |
hdc |
hdd |
| Solaris designation
(/dev/dsk/...) |
c0d0 |
c0d1 |
c1d0 |
c1d1 |
| Use |
HDD |
Opt |
HDD |
HDD |
| Grub disc designation |
hd0 |
|
hd1 |
hd2 |
|
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If you only installed
one OS, you would never need to know any of this but if
you install several, you need to understand how Grub
allocates the names to each drive and partition because
here, we have hdc (the third drive) as hd1.On the
right, you can see how the partitions are allocated (I've
put the numbers in brackets to make them clearer). The
master boot record for the first drive is hd0
and that is what you would use if you wanted to install
grub there. The first partition of the first drive is hd0,0
and if you want to install grub into the boot record for
that partition, that is what you use. When you install
other operating systems, you get a chance to install grub
where you want with them and for the sake of preserving
your system, I would recommend choosing a partition boot
record that has not already got Grub in it - this way,
the configuration files will be preserved.
One way of being able to boot into all of your OSes is
to edit the first copy of Grub's menu file so that it
includes them. All you do is add a line to the
/boot/grub/menu.lst file for each one a bit like the
following.
title OpenSolaris 10
root (hd1,0)
chainloader (hd1,0)+1
This will will make it chainload into Solaris' copy of
grub so you end up with another boot loader menu. And,
there is nothing wrong with that.
However, you might want to have all of your OSes
accessible directly through your first Grub menu. To do
this, you need to do the following
Once you have another copy of grub installed with
another partition, you can log on as root in that OS and
make a copy of /boot/grub/menu.lst which is where the
menu is stored and save that on a drive you can get at
from both systems (you might want to use a small
partition formatted in vfat, a network drive or maybe a
pen drive). Once you get back into your first OS (the one
that the system boots into by default) you open its
'/boot/grub/menu.lst' in a text editor and add the extra
lines (don't delete the old lines, just remark them out
by starting each line you want to remove with a hash mark
'#'. Grub will just ignore these and they will not
appear. You can also do this with commands in grub if you
are experimenting). Now, when you boot the computer, you
should get each OS with a line of its own
However, there are some things that can go wrong.
When you install Linux (or Solaris, FreeBSD and so
on), you get the opportunity to install Grub (the GRand
Unified Bootloader) wherever you want. This includes the
disc's master boot record in addition to each
partition's.
For the first hard drive (normally the master on
channel 0), the master boot record is hd0 and for the
second, it is hd1. For a machine that has been bought
with one hard drive, normally, your optical drive would
be the master on channel 1. However, if you want to have
a smallish drive for your OS and enormous DVD-editing
storage, you might have three HDDs so that any CD/DVD
writing you do will be from a drive on channel 1 (as in
the configuration in the diagram) to the optical drive in
the slave on channel 0 as noted above.
Of course, with Grub, the optical drive is ignored so
in this instance, hd1 is the master on channel 1 which,
under Linux, is hdc. The problem is that: unless you have
run into problems with this, there is no reason why you
should know any of it. As a result, when you have
installed your new, second OS, you can install grub on
the partition boot sector where you think it needs to go
- which will most likely be wrong.
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This can lead to the situation on the right
where you chainload into versions of Grub that are on a
different drive to the one where the OSes they refer to
are installed.Again, this is not a problem unless that
hard drive fails or you do something that overwrites one
of its partition boot sectors.
Putting all of your OS Grub menu list files into one
will solve this but be aware of which OS is installed on
which partition so that you can refer to it correctly.
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GRUB - booting different OSes
Linux will load using Grub, which copes with it well.
You can pass options to it and it understands the file
system. However, there are some where you do have to
chainload. Examples below are OpenSolaris, OpenBSD and
Windows.
This is what a menu.lst file might look like if you
had all of these on your system (note that the partitions
refer to this hypothetical situation - see above for
actual drive/partition designations).
default 0
timeout 12
gfxmenu (hd0,0)/message
title OpenSUSE 10.2
root (hd0,0)
kernel /vmlinuz-2.6.18.2-34-default root=/dev/hda4 vga=0x31a resume=/dev/hda3
initrd /initrd-2.6.18.2-34-default
title 64 Studio
root (hd1,1)
kernel /boot/vmlinuz-2.6.17-1-multimedia-amd64-k8 root=/dev/hdc2 ro vga=791
initrd /boot/initrd.img-2.6.17-1-multimedia-amd64-k8
title Ubuntu
root (hd1,2)
kernel /boot/vmlinuz-2.6.17-11-generic root=/dev/hdc3 ro quiet splash
initrd /boot/initrd.img-2.6.17-11-generic
boot
title OpenSolaris 10
root (hd1,0)
chainloader (hd1,0)+1
title FreeBSD
root (hd1,3,a)
kernel /boot/loader
title OpenBSD
chainloader (hd0,1)+1
title Windows Vista
chainloader (hd0,2)+1
This will give you a menu that looks like this...
| |
OpenSUSE 10.2
64 Studio
Ubuntu
OpenSolaris 10
FreeBSD
OpenBSD
Windows Vista
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64Studio - Multimedia on your 64-bit
PC
With a 64-bit,
multimedia machine running a stable, specially compiled
kernel, what more could you need?
You don't need a lot of power to edit MIDI and if you
have a dedicated sound card that can do all of the
processing for you, even a Pentium 200MHz machine running
Cakewalk Professional 2.0 on Windows 98SE will do an
excellent job.
(Click on the image on the right to
show the image at its true size.)
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However, if you want to do sound
processing, post-production and CD image burning (as well
as CD cover design and so on), you'll need the power of a
modern machine.For a production environment, 64Studio
is excellent. This Linux distribution has a
custom-configured, multimedia kernel, compiled for AMD
64-bit and Intel EM64T processors ( http://www.64studio.com/
) and will handle dual core processors as well.
In addition, it has the stability and security of
Linux and, it's free.
64Studio uses the Gnome interface so it is all fairly
straight forward and easy to follow.
Under 'Sound & Video', you have all of the audio
tools that you should need to write, play and record
virtually anything - whether you are transcribing Rossini
to MIDI for a university project or producing an album
for distribution on CD.
Drum editing can be done with Hydrogen without using
any other programs on 64Studio. You can save the files
from this in MIDI format to import into other songs if
you wish.
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If you want to set up the system to do
general MIDI editing with sound, you need to load the
JACK Audio Connection Kit (Jack Control). Click on
'Connect' and you can see the Audio and MIDI patches.
Next, if you aren't using a sound card, load QSynth and
for MIDI editing, use Rosegarden.(Click
on the image on the right to show the image at its true
size.)
If you want to have all of the fun of a Moog
Synthesiser, run the Alsa Modular Synthesiser (AMS) which
takes MIDI and audio as input and generates audio output.
You can see the audio and MIDI connections in the Jack
Connections kit.
|
| Behind the AMS is voltage control. You
can use a low frequency oscillator to generate a voltage
that changes slowly. This, you can then use as the
control voltage for a voltage controlled oscillator,
voltage controlled filter and so on. You can change the
waveforms of these and even how they change by
restricting slew rate (like a portamento), adding other
voltages or signals to them, using a sample and hold
which will take a sample of the voltage and add it to the
voltage that it already has (integrating it) and then
hold it for a time (which you can also change) and so on. |
 |
| Using a ring modulator, you can do
anything from producing a Dalek voice to making sounds
like bells. The AMS can either be used to produce a live
sound from midi output (say, from Rosegarden) or to
produce a recorded sound for inclusion on a track. Once
you have a patch system set up the way you like it, you
can save the configuration by opening the patchbay form
and clicking on 'New'. In the new patchbay definition
dialogue, where you are asked if you want to create a
patchbay definition as a snapshot of all actual client
connections, click on 'Yes' and then 'Save'.
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MIDI-USB hardware
Unless you have a sound card, you are not likely to
have MIDI sockets on the back of your computer (and even
then, they are likely to be in the form of a 15-pin
D-Series connector socket). There are, however, a number
of devices that will allow you to use MIDI in and MIDI
out and plug them into your computer via USB.
If you go to your local music shop, you will probably
be offered a substantial device that is easily capable of
taking all of the knocks that on-the-road life has to
offer. Some of these also have built-in ADCs which are
completely unnecessary with a PC as they already have
them.
On the other hand, if you are just considering
home-use or, you have a studio where things that have
been connected don't get moved, a cheaper device such as
the one in the photograph will do nicely - it runs on and
integrates into 64-bit Linux without any driver issues.
The problem with built-in leads is that if the leads
are moved around and eventually fail, you have to replace
the whole unit. However, if you never move it, that is
not an issue so a model like the one on the right is
suited ideally for home use or static studio use.
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SoundFonts
There
are many ways of taking the signal input from MIDI and
outputting a sound - AMS and others generate their own
sound but if you want something that sounds like an 1880
Barbe double bass with the original varnish and
silver-wound gut strings, bowed with a black hair bow or
an alto ophicleide, you really need a SoundFont (or learn
how to play one yourself).
The SoundFont format used by QSynth is '.SF2'. These
files can contain just one instrument or a whole General
MIDI set of 128 instruments from an acoustic grand piano
through to a gunshot (plus the drums of course).
Unless you happen to have just what you want, the best
place to look is, of course the Internet. There are many
sites that have free sound fonts. Some are free to use
under any circumstances, some have restrictions that they
can only be used for non-commercial, personal use and
others, you will have to buy.
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Whilst many single-voice SoundFonts are
quite small - a few hundred KiB to several MiB - a full
sound font is in the order of 100MB or so.This is
something worth considering if you are not on at least a
T1 connection.
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Rig-building tips
We hear of all sorts of precautions about static when
assembling hardware but are any of them worth doing?
It is a fact that static electricity will destroy
electronic circuitry such as memory and mother boards.
However, these are a lot less sensitive to it than they
were - things have advanced and whilst CMOS and similar
technologies will still die, they are better protected
now.
Although it is safer,
it is still risky. However, if you take these basic
steps, you can build your own rig or add a memory stick
without any significant risk to the hardware. You need to
make sure that the opportunity for static build-up is not
there and, if it should be, the components are not put at
risk.
So, here is a non-exhaustive list of precautions -
some of which might sound a little odd but they are all
reasonable:
- Don't wear synthetics - wear cotton if possible.
Nylon is a good insulator and charges can build
up on it that will blow up a petrol station so
keep it away from your kit;
- Don't wear shoes. These are thick insulators that
turn your feet into laden jars. Take them off and
wear cotton socks instead;
- Don't use a chair with wheels (unless you are in
a wheel chair of course). These little plastic
wheels turn your office chair into a Vandergraff
generator, especially if you are on a plastic
floor;
- Do keep components in their conductive bags until
the last moment. These aluminiumised bags act
like a little Faraday cage so there is no
electrostatic field inside;
- When you assemble a computer from scratch, the
first thing you install in the case is the Power
Supply Unit (PSU). Installing it places it in
electrical contact with the case. Plug the PSU
into the mains but don't switch it on -- the
earth conductor in the mains lead will keep
everything at zero charge;
- When you take components out of their bags, make
sure that you are in contact with a bare part of
the chassis so that you, the bag and thus the
components also carry no charge;
- The mother board's screw holes have areas of
tinned copper plate to make contact with the
chassis. Once one of these is screwed in (either
to a brass spacer or an indented hole) it is
safe. Plug in the power leads and carry on with
the rest.
Your mobile phone doesn't need to be switched off;
and, your torch doesn't need to be BASEEFA-certified.
Note that at no point did you need a wrist band
although if you are in a wheel chair, that would be a
good thing to use in case you have to move around a lot.
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