Speaker
Frequently Asked General Audio Questions
1. What Does "Clipping"
Mean and Why is it Bad?
Clipping usually means that the maximum output of the amplifier
is being exceeded and the tops of the signal peaks are being "clipped"
off. During these times the cones of the loudspeakers are essentially
receiving a DC signal. This means that most of the energy from
the amp is heating up the voice coil instead of moving the cone.
Usually loudspeakers fail or burn-up because of this heat. (aka.
Thermal Failure) You should also be aware that any clipped signal
in the chain can blow a loudspeaker even if the amplifier isn't
at full output. Most loudspeakers fail because they are driven
by too small an amplifier. The power ratings for a loudspeaker
are only valid for unclipped input signals. So, to avoid problems,
always operate your gear safely below "clip level".
2. How Much Power do I Need?
In general the bigger the amplifier the better. Once you reach
an amplifier's maximum output, you cannot get anymore out of it.
Push the amp input signal any harder and your output will be distorted.
It is also true that most speakers will handle momentary peaks
far in excess of their rated power handling, if these peaks are
clean. (not clipped) SBAL speakers are so efficiently designed
that you could easily use as little as 10 watts for certain applications.
We would recommend however that you have at least a 400 watt per
channel amplifier ( 8 Ohms). This will allow you to get more out
of your system and provide you some safety margin in the event
you need it. (headroom)
3. How Many Speakers Can I Put
on One Amplifier?
Most SBAL speakers are rated as a nominal 8 Ohm load. This means
that the amplifier "sees" an average of 8 Ohms of most
of the musical range when it is hooked up to one speaker. Some
times it is a little less but most of the time it is a lot more.
Most professional amplifiers would prefer to have an 8 or 4 Ohm
load on each side of a stereo amp. If you connect two speakers
in parallel to one side of an amp, the amplifier "sees"
a 4 Ohm load. In most cases this is about as low of an impedance
as you should use. This is true even if the amplifier is rated
to 2 Ohms. If you run a cable from the amplifier to an SB speaker
and then come out of that speaker into another (daisy chain) you
should have a 4 Ohm load. In the case of a stereo amp we recommend
no more than two speakers per channel. If you would like to hook
up more, you should consider more amplifiers or wiring the speakers
differently.
When it comes to wiring speakers, here are the basic rules:
Speakers in parallel - divide the impedance of the speaker by
the number of speakers to determine the load of the amplifier.
Speakers in series - multiply the impedance of the speaker by
the number of speakers to determine the load of the amplifier.
4. How Should I Aim the Speaker
Stacks?
You want to aim your speakers so that they cover as much of the
audience as possible. Try to aim the speakers so that as little
mid/high sound gets reflected off of the walls as possible. If
you have a pair of speakers aim them towards an imaginary point
about half to two-thirds of the way back into the middle of the
audience. If you have more than two speakers on a single side,
it is often a good idea to "splay" them out some to
widen your horizontal coverage angle. For "long throw"
application it is often a good idea to stack your speakers on
top of one another with tweeters in each box as close together
as possible. [For example- place the top cabinet upside down on
top of the bottom speaker and aim them both straight ahead.] Remember
that low frequencies (below 100 Hz) have very long wavelengths
and are fairly non-directional. It is a good idea to keep your
subwoofers low on the floor and next to boundaries like walls/corners.
On the other hand high frequencies have very short wavelengths
and dissipate very quickly. So, keep these aimed high over peoples
heads in the front row.
5. What Kind of Speaker Cables
Should I Use?
It is always a good idea to get heavy gauge speaker wire to connect
your speakers to the amplifier. There will be a lot of current
going to your loudspeaker. In the real world nearly 90% of your
problems will stem from bad connections between your equipment.
We recommend at least 16 gauge wire but prefer 12 gauge. It is
also a good idea to keep your cable runs from your amplifiers
to your speakers as short as possible. Try not to exceed 35 feet
- and do not coil up the excess wire. If you must go further than
35ft, consider moving your amps or getting heavier gauge wire.
6. How Can I Protect My Speakers
From Being Over-Driven?
If you are having problems with "blown" speakers you
may want to consider some added protection. You may want to use
a compressor/limiter in the signal chain before the amplifier
that will keep your signal from clipping. If you want some protection
but cannot afford this solution try adding some inline fuses on
your speakers. You can use standard fast blow AGC fuses in series
with one of the speaker leads. To calculate the proper value use
the following formula:
Amps=square root (Watts/Ohms)
For example begin with the speakers' continuous power rating
(i.e. 450Watts)
Amps=square root (450/8) Amps=7.5
Be conservative and experiment, start with a lower value and work
your way up. Ideally you want the fuse to blow before your amp
goes to clipping.
7. How and Why Do I "Biamp"
a Speaker?
There are several ways to "biamp" a speaker. Several
of the Soundbridge speaker models feature a switch that will allow
the user to quickly switch between the internal full range "passive"
crossover and biamp mode. Biamp mode requires an external active
crossover and another amp. So, why biamp?? There are several reasons
. . . First, your system will have more overall flexibility. Second,
it is easier to control the sound of each speaker. Be aware that
all passive crossovers use up some of the amplifier power and
you have more overlap in the frequency between the drivers inside
the speaker cabinet. When you biamp, more power can be channeled
into the woofers and distortion level often goes down. The trade-off
again is that you must use another amp and an external active
crossover. If you want to biamp it is usually wise to first acquire
a subwoofer. You can then biamp between the subwoofer and the
full range cabinet.
8. How Do I "fly" a Speaker?
Please stop - read and understand the application instructions
thoroughly before flying any speaker. Misuse of a product may
result in damage, injury, and even death. Never suspend a speaker
from the handles!! Always consult the speaker manufacturer to
ensure the working load limit on the speaker hardware and enclosure
is not exceeded. Consult a professional rigger or structural engineer
prior to suspending loudspeakers from a structure not intended
for that use. Always know the working load limit of the structure
supporting the loudspeaker array.
9. Why use a Subwoofer?
True subwoofers greatly enhance the response in an audio systems'
very low end. The difference can be heard and felt! A subwoofer
can provide the punch or impact that is lacking in many small
systems. But, in order to feel bass you have to move a great deal
of air. A subwoofer is designed to do just that and is really
more of a specialist in reproducing the lowest fundamentals in
music. In most cases it is the best way to improve an existing
system. It is a great way to lower system distortion and make
your sound system clearly more understandable. It is often more
cost effective than buying bigger amplifiers or more amps.
10. How Do I Get More Gain in the
Mains and Monitors?
Here are some basic methods you can try to solve this problem:
Try placing a microphone in the middle of the room in the middle
of your speaker stacks. Slowly bring up the gain until the system
starts to feed back. Now, bring down the levels of each of the
squealing frequencies on the main system eq. Be careful not to
bring it down too much - just enough to stop the squealing. Keep
bringing the gain up until you have the levels you want. Now,
try playing a CD you know very well and adjust the eq until it
sounds the way you want. Finally, grab the microphone and speak
into it. Now adjust the vocals until it is clear and crisp. This
is the quickest way to get up and running without a great deal
of hassle.
If your monitors are not loud enough - try to reduce the overall
stage volumes first. Pull all of the frequencies below 80 or 100Hz
down. Move the monitors closer to the performers' ears by placing
them on cases or using them as side fills. If all of this does
not work, try cleaning and/or changing out the microphones. Remember
- its an art as much as a science so be patient. Good Luck!!
The Turbosound range of loudspeaker products, control electronics
and amplified systems has in common one single purpose - to provide
you with the best solution for your application.
Turbosound's unique, award winning designs have been developed
around unorthodox principles, resulting in a special harmony between
high technology in its purest form and a natural approach to the
art of acoustical and electronic engineering. Many principle patents
have been awarded to Turbosound over the years.
Turbosound speakers are very uniqe in sound and design. Ask a
sound engineer about thier quality and sound to see if it fits
your needs.
1-877-477-6432
