400/600 MANUAL.QXP 7/17/98 11:10 AM Page 8
that the 400 and 500GTi should always befrequency operation, it should have its highperfect, it is advisable to keep your crossover
connected in the same polarity as the tweeterand extremely low frequencies blocked bypoints away from the range where your
however. It is possible, that due to theelectrical means in order to achieve the besthearing is most sensitive. Therefore we
difference in the distance the sound travelssystem fidelity and the widest dynamic range.recommend that you try to keep the high-pass
from the woofer/midrange to your earsFor the best performance, we recom-frequency below 250Hz and the low-pass
compared to the distance from the tweeters inmend that an active crossover with aabove 2500Hz. This lets the 400 or 500GTi
a typical system, and the short wavelengths ofminimum of 12dB per octave slope be usedreproduce the entire range of frequencies,
sound at the crossover frequency, that afor the transition point between the subwoofercovering the most important vocal and
connection where the tweeters are connectedand the 400 or 500GTi. The optimumlead instrument fundamentals without a
in reverse polarity from the other drivers in thecrossover frequency for this transition is de-crossover point.
system may actually result in better sound.pendent on the specific components used, theIf you prefer to use all passive
Because there is no way to accurately predictvehicle, and other installation details. crossovers, you will need to construct orAs a
this before installation, we recommend thatgeneral rule, the crossover frequency shouldpurchase either a low-pass or band-pass
you try the connection both ways, and leave itbe as low as possible to achieve the best sys-filter for the midrange driver and match it
in the polarity that gives the smoothest audibletem imaging. You can fine-tune the crossoverto a high-pass filter for the tweeter. When a
transition between the woofer/midrange andafter the installation is complete for the bestmatched GTi Competition Series system
tweeter.sound. Agood place to start your tuningis used, the best crossover choice is the
process is between 50Hz and 150Hz whenlaboratory-optimized, system-matched
System Connectionsusing the 500GTi and between 80Hz andcrossover which is included with the 408GTi or
150Hz when using the 400GTi. In 4-way sys-508GTi system. If you have not yet installed
There are a variety of system optionstems using a midbass driver such as theyour components, we suggest that you
available with the 400 and 500GTi. The600GTi, the crossover point may be raisedconsult your dealer for this system package.
simplest configuration is to use the 400 andhigher without detrimentally affecting imagingThe most advanced system designs
500GTi connected in parallel to a tweeteras long as the midbass drivers can be use active electronic crossovers such as
which includes a high-pass crossover such asmounted reasonably close to the midranges.the JBL GTX2, GTX4 or GTX47 at both the
the 08GTi, GT03 or GT07. Because the 400This higher crossover fre-quency will allow thesubwoofer(or midbass) to woofer/midrange
and 500GTi is specifically designed for midsystem to play louder. Since no crossover istransition point and at the woofer/midrange
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ACEC
