Fender Twin Amplifier owner manual Low Power Option

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of the slave amps such that they NEVER clip with full output from the Twin. Here’s why: Since the signal at the BALANCED LINE OUT is derived directly from the output transformer, the signal is a replica of the voltage present at the speakers in the Twin. If the output of the slave amps never clip, then the voltage at the output of the slave amps will also be a replica of that on the speakers in the Twin. This will preserve the Twin sound. As for the 300 watt minimum rating...

In order for a “slaved” solid-state amp to reproduce the sound of a tube master amp, a solid-state amp needs lots of headroom. For example, because of the way a tube amp interacts with a speaker load, a 20 watt tube amp, when driven into heavy clipping, can pro- duce output signals equivalent to a 180 watt solid-state amplifier. This nine-to-one ratio can get excessive when a 100 watt tube master amp is used. But, if the solid-state slave amp has enough headroom to never clip, and if the speakers used on the slave amp are the same as those used in the Twin, voila! You now have the capability of obtaining large amounts of on-stage Twin sound. We recommend using a Fender Electronics SPL9000(s) with an additional Fender speaker enclosure(s).

If the BALANCED LINE OUT is used as a send to a mixing console, it should normally be pre-equalized before going to the console input. What works well is to run the BALANCED LINE OUT signal through a low-pass filter set to 5 to 6 kHz. The slope of the filter needs to be steep, 18 dB per octave minimum. A handy way to do this is to use the low-pass output of an active crossover, or to use a parametric equalizer. By tweaking the equalization, some very useful sounds can be obtained.

Q. EXT. SERIES JACK — Plug-in connection for extension speakers. This should be used in conjunction with the MAIN SPEAKER jack (item R). By using the EXT. SERIES JACK, the extension speaker is placed in series with the main speaker; therefore, the impedance of the extension speaker adds to that of the main speaker. For exam- ple, by connecting a 4 ohm speaker to each jack, the total load is 4+4=8 ohms. The IMPEDANCE SELECTOR switch (item T) would then be set to 8 ohms. (Note: an additional 8 ohm speaker could be added to the EXT. PARALLEL JACK (item S) for a total of 4 ohms, with the IMPEDANCE SWITCH set accordingly.)

R. MAIN SPEAKER JACK — Plug-in connection for speakers. For proper operation, this jack should always be used first as connection to the primary speaker(s). If this jack is used alone, set the IMPED- ANCE SELECTOR switch (item T) to equal the total speaker load impedance connected to it.

S. EXT. PARALLEL JACK — Plug-in connection for extension speak- ers. This jack should be used in conjunction with the MAIN SPEAKER JACK (item R). By using the EXT. PARALLEL JACK, the extension speaker will be placed in parallel with the main speaker; therefore, reducing the total load impedance. For example, by connection a

16 ohm speaker to the MAIN SPEAKER JACK and a 16 ohm speaker to the EXT. PARALLEL JACK, the total impedance will be (16X16)/(16+16)=8 ohms. The IMPEDANCE SELECTOR SWITCH (item T) would then be set to 8 ohms. (Note: An additional 8 ohm speaker could be connected to the EXT. SERIES SPEAKER JACK (item

Q)for a total load of 16 ohms, with the IMPEDANCE SWITCH set accordingly.)

T. IMPEDANCE SELECTOR SWITCH — Sets the output impedance of the amplifier. The setting should equal the total load impedance as determined above using the three speaker jacks. (The Twin is sup- plied with two 8-ohm speakers connected in series; therefore, the IMPEDANCE SELECTOR SWITCH is set to 16 ohms at the factory.)

LOW POWER OPTION

The Fender Twin can be run with only two output tubes instead of four. This is done by removing the inner two 6L6GC tubes (the 2nd and 3rd large tubes, counting left to right), and setting the IMPED- ANCE SELECTOR SWITCH to one-half of the total speaker load; e.g., with a total speaker load of 16 ohms connected, the OUTPUT IMPED- ANCE SWITCH should be set to 8 ohms. (Remember — half the tubes, half the impedance.) This will produce 60 watts RMS in the OUTPUT HIGH setting, and 15 watts RMS in the OUTPUT LOW setting.

LINE CORD

Your amplifier is equipped with a grounding type supply cord to reduce the possibility of shock hazard. Be sure to connect it to a grounded AC receptacle. DO NOT ALTER THE AC PLUG.

TUBES

The Fender Twin tube complement consists of four Fender Special Design 6L6WGC/5881’s (part number 039214), three Fender Special Design 12AT7’s (part number 023531), and five 12AX7A’s (part number 013341). Fender’s Special Design Tubes provide opti- mum performance in the amplifier. For best results, replace with Fender original equipment tubes only. Tube location lable is in cabinet.

BLACK TOLEX COVERING CARE

The exclusive Fender Tolex covering on your cabinet is especially designed to provide years of lasting beauty. A very light soapy solu- tion on a sponge may be used to remove dirt and residue that may accumulate in the grain. Be careful not to let any liquid come in con- tact with the operating surfaces. DO NOT have the amplifier plugged into a power outlet when cleaning.

TROUBLESHOOTER’S CHECKLIST

-Is the power cord properly plugged into an electrical outlet?

-Is there power at the outlet?

-Is the fuse blown?

-Is the speaker(s) properly connected to the amplifier?

-Is the amp on standby?

-Are all the control knobs turned up above “4”?

-Is the volume control on the instrument turned up?

-Is the instrument plugged into the amplifier?

(Eliminate any effects devices and try another cord.)

If, after checking all of the above, the system is still not operating properly, consult your authorized Fender Service Dealer.

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Contents TwinOwner,sAmpManual TYPE PR266Twin Amp Sound Settings IntroductionTwin Front Panel Functions Fig.1 Twin Rear Panel Functions FigFig. Fig Output Tube Bias Adjustment Instructions LOW POWER OPTION Twin Block Diagram 1 2 GainSpecifications