Blaupunkt PCA2120 Stereo Receiver User Manual


 
8
1 Channel Bridged Subwoofer Mode
By electrically connecting a subwoofer speaker in the way shown
above, you are able to greatly increase the output power delivered
from the amplifier to the speaker. Such a circuit increases the
voltage “swing” across the speaker which increase the power seen
by a factor of 2 to 4 times that in stereo mode.
This is a very logical set-up for systems that are space limited to
allow for only one subwoofer in a vehicle. The number and box
volumes are compensated by simply more amplifier power pushing a single speaker.
Such a configuration is also a surprisingly good performer. These increases in power are always welcome but you must
take care to avoid low impedances (below 4 ohms) since most amplifiers will overheat and shut down if over-driven into
such a configuration. You must also take care that you are not exceeding the thermal, or excursion, power limiting values
for the woofer. Surprisingly high power levels can be achieved with such a system without realizing it thus quickly
damaging the woofer.
SYSTEM CONFIGURATION #1
Subwoofer
Full-Range
Full-Range
Full-Range
Full-Range
4 (main)
For higher output, you can connect a subwoofer
to two output channels. Look for the + and – to
indicate the correct connections.
2 Channel Dual Subwoofer Mode
The largest improvement in sound quality always comes when
adding some kind of subwoofer via a dedicated subwoofer
amplifier and electronics crossover. The electronic crossover
ensures minimal overlap of the bass response with the mid and high frequencies from the other speakers resulting in a
more accurate performance compared to conventional coaxials with additional power.
By installing this amplifier in the stereo mode, you are able to drive two subwoofer speakers and in to low impedance loads
(e.g., 2 ohms) without over heating the amplifiers. Also, such an installation more easily supports a standard 2 speaker
woofer box that may already be constructed. Since two woofers can play 6 decibels louder than one at a given power
(due to acoustical laws of “mutual-coupling”), the resulting sound pressure level is substantial. This is probably the most
common use for a conventional two channel amplifier there is.
SYSTEM CONFIGURATION #2
Subwoofer
Full-Range
Full-Range
Full-Range
Full-Range
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