Line 6 repair

Line 6 Helix repair

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Line 6 Helix Repair

We don’t just do valve amps repairs here at Keld Ampworks. We’re just as happy with Digital modelling equipment repairs!

Line 6 Helix Repair – No Audio on Guitar Input

A customer recently sent in a Line 6 Helix Floor for repair after the guitar input stopped working. The unit powered up normally, all menus and controls functioned correctly, and audio passed perfectly through the auxiliary input. However, there was no signal whatsoever from the main guitar input.

The reported fault was straightforward:

  • No audio from the guitar input.
  • Auxiliary input operating normally.
  • Unit booted correctly with no error messages.
  • All other functions appeared to work as expected.

When a fault is isolated to a single input on a complex digital processor such as the Helix, the problem can lie anywhere from the analogue front-end circuitry through to the analog to digital converter to the DSP chip itself. The first step was therefore to confirm the fault and trace the signal path.

The Line 6 unit uses a clever multi level analog circuit to capture a greater dynamic range with two sepeate ADCs

Signal tracing showed that the guitar input signal was failing before reaching the converter stage.

Further investigation identified several failed capacitors in the analogue input circuit. Although these components showed no visible signs of failure, electrical testing confirmed they were no longer performing correctly, preventing the guitar signal from being coupled through the input stage.

Testing the other caps found several that were on the point of failing.

The defective capacitors were replaced with high-quality equivalents matching the original specifications. Once fitted, the guitar input immediately returned to normal operation.

The Helix was then subjected to extended testing all inputs and presets, with all inputs, outputs and switching functions verified. The repaired unit operated flawlessly throughout the test period, with both the guitar and auxiliary inputs functioning exactly as intended.

Modern digital guitar processors rely on both analogue and digital circuitry working together. While software faults are often suspected first, relatively small analogue components such as capacitors can prevent an otherwise fully functional unit from passing audio correctly.

This Line 6 Helix repair was completed at component level, avoiding the unnecessary replacement of expensive circuit boards and returning the processor to full working order.

If your processor has no signal on the guitar input, intermittent audio problems or other input-related faults, a professional Line 6 Helix repair can often restore full functionality without the expense of replacing the entire unit.

If you’ve got a Line 6 Helix repair please get in touch!

Wireless mic repair – Line 6 XD-V30

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Wireless mic repair - line 6 XD-30

This wireless mic repair came in from the singer of Newark soul band the Acetones.

Both units powered up but no sound came from the receiver when the mic was used.

Upon investigation I discovered that the transmitter and receiver were able to communicate. They use 2.4GHz. The unit has 6 wireless channels, all of which were communicating, but not passing audio.

wireless mic repair

I discovered that the connection between the capsule and the transmitter was broken. The connection was made by 3 sprung pins on the transmitter and 3 concentric gold plated rings on the capsule. It’s a nice idea to allow easy swapping of capsules and easy manufacture, but here it wasn’t working properly! I soldered the two modules together permanently to ensure a good connection.

If you have a wireless mic repair, please get in touch.

Line 6 Repair – Pod XT live

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Line 6 Repair

Oh dear! This line 6 repair was a bit of a mess – you can see on the right hand side of the pic that the board has been burnt by some over heating rectifier diodes.

Most pedals run from a DC supply, but a lot of line 6 gear uses and AC supply. A popular reason for doing this is to allow the designers to simply create positive and negative DC power rails in the unit. They don’t just do it to confuse guitarists! The AC supply must then be rectified by diodes and filtered with caps to create a DC supply. Its these diodes that were destroyed.

Anyway, I was surprised to see that the diodes on this unit look like 1A packages when the unit is specced for 2A intake. The line 6 repair procedure was therefore to replace these with meaty 3A diodes to prevent further problems. The owner is lucky that none of the sensitive DSP and microcontrollers appeared to have been damaged as these could not have been replaced.

Due to the complex nature of the DSP kit that they use, line 6 repairs can sometimes be uneconomical – whole boards sometimes have to replaced in line 6 repairs. However this line 6 repair was completed in the first hour and was cheap for the customer. If you have a line 6 repair job for me, please get in touch and I’ll try to advise.

Myth avoidance: Pedals made with surface mount technology are not that hard to repair, though very fine pitch SMT can be harder. What is next to impossible is the replacement of DSP and MCU chips. Since I don’t have the code that was loaded onto these I can’t repair them, and so these repairs can only be done by a board replacement.