Grant Avanti Amp Restoration
A friend of mine brought me this fairly rare Vancouver-made amplifier to fix up. It had some scratchy pots, but more importantly it was made in the “Widow Maker” style, lacking a power transformer. This can be quite dangerous. Depending on how the AC plug is inserted, and the wiring in your house/studio, it’s possible that the chassis could be connected to live AC, and consequently your guitar would be as well.
The solution is to install an isolation transformer and to install a grounded AC plug. This would bring the potential of the chassis to earth ground, and keeping everybody safe and shock-free. Redditor burkholderia found me an appropriate transformer at Allied Electronics, a Hammond 6K140HF, and the price was right.
Along with this upgrade, I cleaned out the controls, and replaced a few aging capacitors and input jacks, bringing this great-sounding amplifier back to life.