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MXR M103 Blue Box Octave Pedal , $99.99 - Add to Cart Skip to Product Information

MXR M103 Blue Box Octave Pedal

2-octave Down Fuzz Pedal
MXR M103 Blue Box Octave Pedal
MXR M103 Blue Box Octave Pedal

Or we have a Certified Open Box model for just $89.99! Learn more
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MXR M103 Blue Box Octave Pedal
In Stock!

Only 2 left in stock! More on the way.

Chaotic - With a Healthy Dose of Fuzz!

This article was Written By

Our Product Research Team

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Are you bored with "conventional" distortion boxes? The Blue Box from MXR is a monster distortion pedal, giving you both an aggressive fuzz that'll rip your head off and an unpredictable (in a good way!) two-octave-down tone generator. It's dead-simple to use: turn the Output knob to dial in the amount of fuzz you want and use the Blend knob to dial in how much double-octave sound you want. More conservative settings on the Blend control yield familiar sounds ("Fool in the Rain"). Dial the Blend up to 100% and the MXR Blue Box starts spitting and glitching 8-bit-style nonsense on par with smashing an Atari (again in a good way!). There's a ton of fun and chaos to be had here, which is why the MXR Blue Box has become a go-to pedal for the sonically adventurous.

MXR Blue Box Fuzz-Octave Pedal Features at a Glance:
  • Aggressive fuzz tones
  • 2-octave-down tones
  • Output and Blend controls
  • 9V battery operation or optional power supply
A staple of noise rock and beyond - MXR's Blue Box!

Warranty Info

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Offer applies only to single-receipt qualifying purchases. Select manufacturers may require that only the manufacturer’s products qualify towards the minimum purchase amount needed to be eligible for promotional financing. Otherwise, an invoice that meets the minimum purchase amount and contains at least one qualifying manufacturer product is eligible for promotional financing. No interest will be charged on promo purchase balance, and equal monthly payments are required on promo purchase until it is paid in full. The payments equal the amount financed divided by the number of months in the promo period, rounded up to the next whole dollar. These payments may be higher than the payments that would be required if this purchase was a non-promo purchase. During the last month(s) of the promo period the required monthly payment may be reduced due to the prior months’ rounding. Regular account terms apply to non-promo purchases. New Accounts as of 07/31/2025: Purchase APR is 34.99%. Penalty APR is 39.99%. Min Interest Charge is $2. Existing cardholders: See your credit card agreement terms. Subject to credit approval.

Offer applies only to single-receipt qualifying purchases. No interest will be charged on the promo balance if you pay it off, in full, within the promo period. If you do not, interest will be charged on the promo balance from the purchase date. The required minimum monthly payments may or may not pay off the promo balance before the end of the promo period, depending on purchase amount, promo length and payment allocation. Regular account terms apply to non-promo purchases and, after promo period ends, to the promo balance. New Accounts as of 07/31/2025: Purchase APR is 34.99%. Penalty APR is 39.99%. Min Interest Charge is $2. Existing cardholders: See your credit card agreement terms. Subject to credit approval.

The estimated required monthly payment shown which excludes taxes and delivery equals the amount financed divided by the number of months in the promo period, rounded up to the next cent. During the last month(s) of the promo period the required monthly payment may be reduced due to this rounding. These payments apply only with the financing offer shown. If you make these payments by the due date each month, you should pay off this amount financed within the promo period, if it is the only balance you are paying off. If you have other balances on your account, this payment will be added to any other minimum monthly payments.

Applies only to select items from this manufacturer. Ask your Sweetwater Sales Engineer for more details.