Listing Detail Tabs

This is a Dextermods pedal mod kit for the Marshall JH-1 Jackhammer pedal . This auction does not include the pedal.

The kit includes all hardware, resistors, capacitors, and includes a free installation of the mod kit.

I've got a nice collection of these Marshall pedals, and have mods for most of them. The Jackhammer proved to be a real challenge.

There are a lot of generic mods out there that try to fix the muddy tone that plagues this pedal, mostly by changing the diodes that are used to generate the clipped distortion sound. This is a cheap and easy fix but it doesn't really get to the heart of the problem with this pedal, which is the op amps.

It's a shame because a little bit more achieves a whole lot.

The Dexter Mods version of the Jack Hammer begins with removing the problem op amps and in their place new hi fi op amps are placed in sockets.

We can then address the other problems, the muddy overdrive and distortion is fixed by changing the clipping section to open up a livelier and more dynamic dirt that finally delivers the promise of this pedal to players. Some well placed capacitor tweaks fixes the overbearing amount of bass present which formally killed the overall sound of the unit .

I have been working on this mod for a few months now and I have modded several JH-1's but the op amp mods are the key to getting this pedal to be worthy of the Marshall name.

Don't settle for less.

Comes with a super bright blue LED.

The mod is guaranteed. If there are any problems when you receive the pedal simply return to me, I'll service it and send it back.

Questions are welcome but please check the Dexter Mods FAQ here first:

Why do most people choose Dexter Mods?

GST invoice available on request.

Check my feedback.
There were no answered questions or comments placed on this listing.
Your question and answer privileges have been disabled.
You must log in to view questions and answers on this listing. We recommend reading questions before you make any purchases.
You must log in to ask or answer questions posted. We recommend reading questions before you make any purchases. Available only to approved bidders. You must be an authenticated member to ask questions Find out more about becoming authenticated. Your account is in debt Your current account balance is You must credit your account to use this feature.
Firearms licence #
Firearms licence holder name
First name is required
Last name is required
Your current account balance is Please note you will lose your question and answer privileges if your account is in debt for more than 2 weeks. Credit your account.
I confirm that I am over 18 years old.
To prevent your personal details being misused please do not put emails or phone numbers in questions. Failure to comply may result in the suspension of your account. The seller cannot add a Buy Now price once bidding has started.

Shipping options

  • Anywhere within NZ via NZ Post Untracked$8.00
  • Anywhere within NZ via NZ Post Tracked$11.00
  • Seller does not allow pick-ups
  • Seller location: Whakatane, Bay of Plenty, NZ

Payment options

  • Other options
    NZ bank deposit