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Cyberpunky's Staging and Imaging
Tips page
What does imaging and staging even mean?
Staging is about where we would here a live band coming from,
if we closed our eyes, and could accurately hear this band playing on a stage
in front of us, the hence the term stage, providing this band was recorded well
of course. Do we hear the stage out over the bonnet or is it over the dash,
is the stage wide, and does it have depth, is it at the right height, and does
it have ambience. Imaging is about the focus and placement of instruments or
sounds, across this stage.
How Do We Judge All This
To judge all this we can break it down into 4 sections, relating
to staging, plus imaging and ambience. All of these factors are interrelated
and so it is hard to do well overall, if one or more areas are poor. If we play
a live bands music and we can clearly hear they are out over the bonnet or beyond,
the car would have good stage position relative to the listener's position.
If we can hear that the band is playing over wide area, across the bonnet, then
the stage is considered wide. Stage depth is the ability to hear a singer up
front and a bass guitar down the back for example. The height is wether the
band sounds up in the air or below the floor or just right (dents in the bonnet
:)).
When listening for imaging we like to hear clearly the point
something comes from. Sometimes vocals may be sharply placed and focused, but
other instruments are less defined, and so having good imaging and staging,
is far harder than simply mounting tweeters on the A pillars. Then we also have
ambience, and this about, does it sound big and large, if it is an orchestra
in a large concert hall, or small and confined, if it's a small acoustic ensemble
in a small venue, etc.
Listening
The best way to listen for these factors is to use a reference
disc that comes with tracks with stage maps, so you have an idea of what instrument
is meant to be placed where, for each track. I use the IASCA disc and manual
but I believe Chesky and others make similar set up discs with maps etc. The
next thing to do is to shut your eyes and listen carefully, as sometimes these
things are very subtle, and having eyes open can influence, or distract us,
from actually listening properly. Now armed with all this info and set up discs
etc, its worth trying to get a listen to a high end home stereo to see how all
this works in reality. Often stores that sell this hi end stuff will allow you
to audition stuff capable of revealing all these desired factors to do with
staging/imaging. Once you have heard what you are trying to achieve, it will
make it easier to tell when you have mounting position right or at its best
in your car.
Kick Panel Mounting
The kick panels in most cars, place the speakers the furthest
away from our ears, compared to the doors or dash, where the nearside speaker
will be very close. This kick panel mounting is said to be more equidistant
than door mounts, as both speakers are closer to the same distance away, from
our ears. This is closer to a home set up where we can sit in the exact middle
of speakers to maximise the stereo effect, and be same distance from left and
right speaker. Putting the speakers just in the kicks is not all there is too
it, as the angle and position have a significant effect on imaging/staging.
Mounting
Now the tough part, how do we make sure our kick panel mounts
image/stage properly or to their best? The simple answer is it takes a long
answer :) Due to position and angle being critical it often is hard to play
around with the speakers you will use, due to midrange needing enclosure and
once you build this, you are committed to mounting angle and position and so
cant adjust for angles or slight position changes etc. The answer is to use
a small pair of speakers like Tandy's minmus7 speakers or similar. These are
small but produce a fairly full range sound and so can be used to try positions
and angles, to judge effect. Using back-strapping or small bean bags underneath,
to support these test speakers, as this can allow you to accurately adjust positions
etc and take time to evaluate each adjustment. Once the position and angles
are determined for the best results, it is a matter of replicating or transferring
these factors to final enclosure/panel. Making kicks is another story :) Do
not be scared to play around with angles of up to about 45 degree from flat.
The speakers should literally disappear, and placing where they are, with eyes
shut is almost impossible, in a well-executed set up. Once we achieve this ideal
situation, stage height usually is not an issue.
What If Kicks Are Not an Option
Does this mean that if you cannot use kicks you are doomed
to poor stage/image? No, it just means perfection may be hard, if not impossible,
to achieve, but improvements over factory mounting will still occur, but may
take experimentation. If limited to door mounts then the first step is to angle
the midrange up at least 15 degrees from flat. This will stop the speakers firing
directly at each other and avoid standing wave issues. The trick is then to
play around with tweeter position and angles to try to get the best possible
results. I find a handy rule of thumb is to avoid moving tweeter any more than
a hand span away from the midrange, as often going any further can result in
a noticeable separation of mid and highs A pillar mounts don't suffer any height
issues, that's for sure, but usually cause noticeable separation between mids
and highs. The highs may appear to image well but if you play the 7 snare beat
track, as used in IASCA competitions, then you will hear that this position
does not usually image well with this track. A snare beat covers a lot of the
frequency range and so, a lot more information than just the tweeters provide,
is needed, to get these 7 snare beats, to line up ruler straight. The other
problem with A pillar mounts is the reflections issue. Due to glass being highly
reflective of sound waves, it usually pays to keep tweeters below any glass
to avoid any possibility of a reflection. Glass will usually make treble overly
bright and due to reflections will tend to blur or defocus imaging. It certainly
does not help anything and can often result in extreme EQ adjustment to tame
brightness, with out adding to imaging, apart from at a superficial level, and
only compared to another poor position. There are no easy answers to a good
stage and it is a very rare car, which exhibits a great stage.
Horn Loaded Compression Drivers
Some competitors resort to Horn Loaded Compression Drivers
(HLCDs), as these always stage and image well, if mounted properly, but can
suffer if not EQed heavily, and are a major hassle to fit in most cars and simply
cant be fitted to some cars. HLCDs have the advantage of working from 20,000
Hz down to around 600 Hz, which is a huge section of the frequency range we
are trying to reproduce, and so provides single point source (ideal). HLCDs
can suffer from a honkyness, that is often due to resonance, poor design, cheap
compression drivers etc, and often this effect is impossible to remove via EQ,
and the better HLCDs, that don't do this, are often out of reach of the average
person, due to high price. In Angelo Kanci's award winning BMW, the top of the
range, Veritas HLCDs are used, these are then coated for resonance and have
had the standard compression drivers replaced with Radian units. The Radian
drivers are over $5000 worth alone, and this is added to HLCDs that cost around
$4000 in the first place. This is obviously not the answer for most people,
even if very serious about their sound quality. Anyway its never easy getting
good results in any car, as we are compromised from the start, but often that
means when we do get great results, the extra effort is worth while, and can
be very rewarding.
Hope it helps
Peace
Cyberpunky
©Cyberpunky2001
Copyright ©cyberpunky 1997©
Last revised: March 01, 1999.