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Amptweaker Curveball Jr EQ/Boost Guitar Effects Pedal

Amptweaker Curveball Jr EQ/Boost Guitar Effects Pedal, 3 Band EQ w/ Dual Boost Functions, True Bypass Switching, Works Great w/ Guitar/Bass/Acoustic/Other Instruments, Made in the USA


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Discounted Price $189.00
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The Curveball is a 3 band EQ with dual Boost functions and can even be used as a clean channel preamp.

Product ideas Amptweaker has received for EQ have ranged from graphic EQ's, to fully adjustable parametric EQ's and all points in between. The Curveball sets up various EQ curves using a simple to understand 3 band active EQ, so it's flat when set straight up. The all important Mid frequency is selectable using the Mid switch, to easily simulate 3 band passive EQs from classic US amplifiers, UK amplifiers, and the Thrash EQ setting puts the middle right in the sweet spot for metal. The Mid knob also boosts in a peaky way through that same frequency range, making this a great way to dial in great parked wah tones by boosting it. It's also easy to boost some mids when changing to a second guitar that is hollow and hard to match up to your rig.

The Curveball can be used in front of distortion to add more gain while tailoring the attack and thickness of the distortion, and Amptweaker's Tight switch helps dial that in with the Fat-Normal-Tight settings. The Low knob boosts in a shelving way, but cuts more like a Tight control so you can further optimize the attack. The High EQ also boosts in a shelving way, but rolls off highs more like a guitar tone control. This provides the most flexibility in tweaking your front end boost.

The secondary boost feature is a great way to either make up for two different guitars or set up two different boost amounts (open battery door to set the boost for either more gain or more volume). By pressing and holding the footswitch, the LED changes from Orange to Green to let you know that the EQ is locked ON, and the secondary boost is primed and ready to go. Press the footswitch again and the LED turns red, and gives you up to 10dB of additional boost. This works exceptionally well after distortion, since you can use it for solos to give you a noticeable volume increase. Used in front of distortion, you'll get a secondary heavier gain boost than with it off.

Another obvious use is to put the Curveball after distortion pedals, or in the effects loop of your amp. It can be used to change a moderately normal sounding amp in to a metal monster just by judiciously cutting the mids and boosting the volume back to about unity volume. This is when the secondary boost feature comes in handy.

And lastly, with a lot of Amptweaker's customers using distortion pedals as preamps direct into the power amp or effects return, the Curveball makes a perfect companion since you can easily get great clean tones with it. Patch it into your TightMetal Pro's SideTrak loop, and then run into the power amp, and the Curveball will work as your clean tone when the TMP is off. You can even get some distortion from it if you run it at lower voltages, but for the cleanest tone use 18V.

As with all of Amptweaker's pedals, the Curveball also features true bypass switching, and a thumbscrew-removable bottom plate with special holes to even accommodate tie-wrap or screw-in pedalboard attachment methods.


  • Works Great w/ Guitar, Bass, Acoustic Guitar, or Other Instruments
  • Low, Mid High Active EQ, Flat When Straight Up
  • Fat/Normal/Tight Switch to Adjust the Guitar's Attack
  • US/UK/Thrash Mid Switch Sets the Mid Frequency to Standard Passive EQ Spots
  • Crank the Mid for Parked Wah Sounds
  • Volume Control to Cut or Boost Level
  • Press & Hold Footswitch to Access Extra Boost Knob
  • Internal Switch Sets Boost to Gain or Volume Boost
  • True Bypass Switching
  • Made in the USA
  • 5 Year Limited Warranty
  • Runs on 9V to 18V Battery or Power Supply (Not Included)

Get your Amptweaker Curveball Jr EQ/Boost Guitar Effects Pedal today at the guaranteed lowest price from Sam Ash with our 45-day return and 60-day price protection policy.

Things You Will Get:

  • EQ/Boost Pedal


by PowerReviews
Effect Type EQ/Boost
Inputs 1 x 1/4"
Outputs 1 x 1/4"
True Bypass Yes
Control Layout Low Knob, Mid Knob, High Knob, US/UK/Thrash Switch, Volume Knob, Fat/Normal/Tight Switch, Gain/Volume Boost Switch (Internal), On/Off Footswitch
Battery Power Yes
Battery Type 9V
Power Supply Type 9V or 18V DC Adapter
Power Supply Included No
Weight 0.5 lbs.
Dimensions 2.7 x 2 x 4.65 inches (WxHxD)
Series Drive/Boost
Model Curveball Jr
Warranty Info:

5 Year Limited Warranty, Amptweaker, LLC warrants this pedal against defects due to faulty materials or workmanship for a period of five years from the date of original retail purchase. This warranty is non-transferable, so please keep your receipt for proof of purchase. If the pedal becomes defective within the warranty period, Amptweaker, LLC will repair or replace it free of charge, only after contacting Amptweaker, LLC and receiving authorization and instructions to return it freight prepaid by the purchaser. This warranty is void if the product has has been repaired or altered by anyone other than the manufacturer, or if damage to the product resulted from accident or misuse. There are no warranties which extend beyond the terms described herein.

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