SWR 350X Instrucciones De Funcionamiento página 18

350x Power Amplifier Minimum Impedance Ratings
Here's what this means to the power amp in the 350x. As mentioned previously, the 350x contains a
mono power amp, which makes things fairly simple. The Minimum Impedance Rating of the 350x is 4
ohms. This means that you can safely connect:
• One 8 ohm speaker enclosure
• Two 8 ohm speaker enclosures
• Two 16 ohm speaker enclosures
• One 4 ohm speaker enclosure
The optimum operating impedance for the 350x is 4 ohms. This way you get a good amount of power from
the amp (350 watts) without operating too closely to the minimum impedance—or, in simple terms, with-
out running the amplifier too hot.
(For an even more in-depth discussion of impedance and power rating issues, go to the SWR Website at:
www.swrsound.com, click on "Press," then click on "Articles," then click on "Plug and Play – Setup Tips
for Amps and Speakers" – an article by SWR founder Steve Rabe that ran in the August '92 issue of Bass
Player Magazine.)
350x Power Delivery Capabilities (Power Ratings)
After determining how the number of cabinets you wish to run affects the total operating impedance, you
need to take into account the power handling capabilities of your speaker cabinets as compared to what
the 350x can deliver at that impedance. Those ratings are as follows:
350 Watts @ 4 ohms
240 Watts @ 8 ohms
So if you have two 8 ohm speaker cabinets, they will each get up to 175 watts of power, and more during
transient peaks. A single 4 ohm cabinet will get 350 watts of power, and again, more during peaks. Make
sure your speaker cabinet(s) can handle the power.
Remember, it's always better to have a little too much power than just barely enough. If you find yourself
constantly wanting more power than the 350x provides, either:
a) Tell your bandmates to turn down;
b) Tell the monitor engineer to turn you up;
c) (best option) Take the time to investigate getting an external power amp and/or additional speaker
cabinets to supplement your rig.
NOTE: The frequency response of the 350x is far greater than usually found in musical instrument
amplifiers (20 Hz to 40K Hz). This was engineered in order to give the bass player the same punch
and clarity on stage as found in the studio or concert P.A. systems. Therefore, it is doubly important
that you are aware of the impedance and power rating of the speakers that you intend to use, and
that they are compatible with the 350x. Speakers that have been overdriven are easy to detect and
generally do not fall under a manufacturer's warranty.
Speaker Output Jacks
Two 1/4" phone jacks and two Speakon Jacks (all wired in parallel) are provided for connection of the
350x to your speaker system. Whenever possible, use of the Speakon jacks is recommended. Speakon
jacks and connectors offer the best possible connection and are far superior to banana or 1/4" phone
jacks in that they not only lock in place (preventing accidental disconnection), but also offer a greater and
more stable connection surface. This solid connection provides a more effective transfer of power to your
speakers.
Only SPEAKER CABLE of 18 gauge or heavier (the heavier the cable, the lower the gauge) should be used
to connect your 350x to your speaker system. Do not use shielded instrument cable to connect your ampli-
fier to your speaker enclosure, as this can result in intermittent power loss, cause your amp to oscillate
and damage itself and/or your speakers, and render the cable useless for any purpose.
Note: Unlike most amplifiers on the market, the 350x can be used for recording purposes without
speakers attached to the speaker output jacks (using only the Balanced [XLR] Output).
18 • 350x