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tion with the level of the clean “Channel One.” How do you control the level of “Channel One?” By using
the Gain Control, which controls the level of the clean bass signal in the preamp.

Also, the EQ Controls are located after the Overdrive circuitr y, so they can have a drastic effect on the
distorted tone. (The treble control is especially useful for adding or removing a nasty edge to your
Overdrive sound.) And don’t forget about the Limiter, which, when dialed higher than you might think nec-
essar y, is often useful in combination with distor ted signals to create warm, smooth overdriven tones.
Finally, if you engage the effect and both the Drive and Level controls are set to minimum, there will be
little or no change in your tone. This is normal.

SubWave™ Controls

Once again, based on the circuit from SWR’s Mo’ Bass, the SubWave™ on your 750x is a lightning-quick
sub-octave wave engine with tracking superior to other models of sub-octave ef fects currently on the mar-
ket. In plain terms, it hears the note you play and immediately generates a signal one octave below it—all
the way down to low “C#,” “C,” or even low “B” on some basses!

SubWave™ Activator Switch

Located directly above the SubWave™ Level Control, this is an illuminated push-button switch that acti-
vates the SubWave™ effect. When engaged, the switch cap will illuminate in blue. Push once to engage,
then again to disengage. (The SubWave™ effect can also be switched on and off via footswitch; please
see the heading titled “Effects Footswitch” in the “Rear Panel Features” section later in this manual.)

SubWave™ Level Control

Once the SubWave™ effect is engaged, you can use this control to determine the amount of effect to be
blended in with your original (“clean”) bass signal. Turning the control clockwise will increase the amount
of effect, while turning the control counter-clockwise will decrease the amount of effect. When the control
is set fully counter-clockwise to “MIN”, no effect will be heard, even though the effect is engaged and the
Activator switch is illuminated in blue. This is normal. Also, when the control is set fully clockwise to
“MAX”, the “clean” bass signal will still be present…along with plenty of sub-octave effect. As always,
your ears and the desired musical application will be the best judge in setting this control. 

(Keep in mind that the Bass Level control will have a significant impact on the perceived level of the
SubWave™ effect as well, as it follows immediately after the SubWave™ in the signal chain. Please read
below.)

Balancing Levels When Using Both Onboard Effects

If you wish to use the Overdrive and Subwave™ effects at the same time, here’s something you should
know. The Gain control effects the level of the Subwave™ effect, but it does not affect the Overdrive. So, if
you’re balancing the overall Overdrive signal against the clean sound, it’s worth remembering that if you
turn the Gain Control down, you’re also reducing the amount of Subwave™ present in the final blended sig-
nal. Basically, when it comes to setting levels for using both effects at once and switching back and for th
between sounds, you have three controls you can adjust: the Gain Control, the Overdrive “Drive” Control,
and the Subwave™ Level Control. Experimentation is encouraged.

750x – ACTIVE TONE CONTROL SECTION

Bass Control

The Bass control employs a shelving-type circuit and boosts or cuts the bass re/–15dB, from
about 30 Hz to 100 Hz, centered at around 80 Hz. Star ting at the control’s mid-position (“center-click”),
turning the control counter-clockwise cuts the bass response, and turning the control clockwise boosts the
bass response. 

You’ll find that the Bass Level control will boost or cut the SubWave™ effect along with the “clean” bass
signal; that’s because of the range of frequencies covered by this particular control. You can use both the
Bass and SubWave™ Level controls to get a good balance between how much bass you want in your clean
sound, and how much of a bass boost you want when engaging the SubWave™. Some users will want a sig-
nificant boost, while others may be striving for a more consistent level (or “unity gain”). Again, let your ears
and musical taste be the judge. 

750x OWNER’S MANUAL • 7

Summary of Contents for 750x Bass Amplifier 750x

Page 1: ...750x OWNER S MANUAL SWR CORONA CA USA ...

Page 2: ...on or pinched by items placed upon them paying particular attention to cords at plugs and the point where they exit the product K Lightning For added protection of this product during a lightning storm or when it is left unattended and unused for long periods of time unplug it from the wall outlet This will prevent damage to the product due to lightning and power line surges L Overloading Do not o...

Page 3: ...he famous SWR clean tone and without having to lug around an 80 pound all tube amplifier Second there s our SubWave circuit which produces a tone an octave below the original signal and tracks as well or better than anything else on the market today The effects are foot switchable and we ve provided a dual footswitch for your convenience Additionally the unit is now lighter quieter in terms of ove...

Page 4: ... Off switch 750x REAR PANEL FEATURES XLR Pad Level control XLR Output jack XLR Mode switch Direct Direct EFX Line Ground Lift switch for XLR Output jack Side Chain Effects Loop Effects Send and Effects Return 1 4 jacks Tuner Out Jack Preamp Out Jack Overdrive Activator Footswitch jack SubWave Activator Footswitch jack Fan Mode switch Stereo Headphones Jack Two Speakon and two 1 4 Speaker Output ja...

Page 5: ...r cabinet If your cabinet is a 4 ohm enclosure the 750x will deliver will deliver 750 watts into it If your cabinet is an 8 ohm enclosure it will deliver 450 watts into it This is a loud amplifier Be sure to check the power handling capabilities of your speaker cabinet before connection and operation Using Two Speaker Cabinets Using a speaker cable of 18 gauge or heavier the heavier the cable the ...

Page 6: ... to an equal level You should now hear the sound of your instrument amplified through the 750x into your speaker cabinet s Eventually you may want to reset the Gain Control in conjunction with your desired settings for the Overdrive effect but we ll get to that later on in the manual 750x FRONT PANEL FEATURES Input Jacks Both input jacks accept a standard 1 4 phone plug and both inputs can be used...

Page 7: ...se ratio and pre vent unwanted clipping of the preamp section Note The Gain can serve as an EFFECTS SEND LEVEL ADJUSTMENT If your effect is being overdriv en turn down the Gain control and readjust your Master Volume for overall loudness Preamp Clip LED The Preamp Clip LED will light whenever the preamp tone section or output buffer reach clipping run out of headroom This function does NOT monitor...

Page 8: ...lso be switched on and off via footswitch please see the heading titled Effects Activator Footswitch Jacks in the Rear Panel Features section later in this manual Overdrive Drive Control Located on the outer portion of the dual concentric knob underneath the Overdrive Activator Switch the Drive Control adjusts the amount of distortion present in the signal Some people refer to this element of an o...

Page 9: ... and the Activator switch is illuminated in blue This is normal Also when the control is set fully clockwise to MAX the clean bass signal will still be present along with plenty of sub octave effect As always your ears and the desired musical application will be the best judge in setting this control Keep in mind that the Bass Level control will have a significant impact on the perceived level of ...

Page 10: ...ntrol until the desired area you wish to cut or boost is found 3 Adjust the Midrange Level control to the desired amount of cut or boost Midrange Frequency Control The Midrange Frequency control sets the area that is to be cut or boosted by the Midrange Level control If the Midrange Level control is set at mid position turning the Frequency knob will have NO affect Some hints If you need to cut th...

Page 11: ...iter LED will not illuminate when playing at levels not high enough to engage the cir cuit Note If you have the Limiter set at MIN and you hear a loud sharp distortion present in your sound and the Preamp Clip LED is not lighting up engage the Limiter by turning up the control If the distortion goes away you were probably clipping the power amp which is not a good thing Remember the Limiter circui...

Page 12: ... when in the DIRECT position with one important exception the Overdrive and SubWave effects are present What s the benefit of this setting We ve found that most people who use effects pedals prefer to use them in front of the amplifier In other words they run their bass into the effect pedal s input then from the effect pedal s output into the front of their amplifier In live applications where so...

Page 13: ...er trying both positions of the ground lift there is probably 1 A bad cable or connection somewhere between your Balanced Output jack and the snake leading to the mixing console 2 A dirty or miswired A C socket 3 Miswired or poorly wired A C in the building 4 Fluorescent lighting directly above you or in close proximity especially when using single coil pickups 5 A cell phone in your right pocket ...

Page 14: ...0 2 An unbalanced output suitable for recording or live mixing board purposes The output impedance of the Effects Send jack is 100 Ohms Effects Receive This jack s primary function is to complete the Effects Loop circuit by routing the post external effects device signal back into the power amp of the 750x where it can be blended back in with the original signal by using the Effects Blend control ...

Page 15: ...to leave at least a 1 2 clearance between the vent on the top of your 750x and anything you wish to put on top of it This will allow for the heat generated by internal components to escape You have complete operational control of the fan via the Fan Mode Switch Setting the Fan Mode Switch to the On position activates the internal cooling fan Setting the switch to the Off position deactivates the c...

Page 16: ... d call that a good amount without operating too closely to the minimum imped ance or in simple terms without running the amplifier too hot That said the 750x is rated to operate safely when connecting One 8 ohm and one 4 ohm enclosure 2 6 ohms total Three 8 ohm enclosures 2 6 ohms total These two hookups will provide 850 watts of power which should be more than enough for just about any applicati...

Page 17: ...ower and be loud er than the other Since your 750x is a mono amplifier it is best to use cabinets of similar impedances when using more than one The best two cabinet setup is to use two 8 ohm enclosures Note The frequency response of the 750x is far greater than usually found in musical instrument amplifiers 20 Hz to 40 kHz This was engineered in order to give the bass player the same punch and cl...

Page 18: ...ating Do not defeat the purpose of this feature by using a higher rated fuse as it can void your warranty Proper size of the A C fuse for all countries is 3AG Proper rating of the fuse is as follows United States 10 amp slo blo Japan 10 amp slo blo Europe 230V 240V 5 amp slo blo A C Cord Receptacle This receptacle accepts a standard A C power cable supplied with the 750x in the United States used ...

Page 19: ...ation to power produced in the speakers The difference in these two figures can be as high as 300 watts This would be the equivalent of putting a 300 watt light bulb inside a metal box which would obviously get quite hot Most musical instrument amplifiers on the market today use steel for their chassis which does not conduct heat as well as aluminum The 750x uses an all aluminum chassis and front ...

Page 20: ... you may also have other rights which vary from state to state For a complete list of Authorized FMIC Service Centers and the latest SWR news interviews and more check out our website swrsound com SHOULD YOUR SWR AMPLIFIER REQUIRE SERVICE OR REPAIR PLEASE USE THE FOLLOWING PROCEDURE Locate your original receipt showing date of purchase model and serial number Determine the closest Authorized FMIC ...

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