JAMES LEBIHAN, All linear power supplies and Switching Mode Power supplies need to use an external AC power conditioner unit to block and filter out AC line frequencies other than 60 cps, harmonics, spikes, surges, noises from power tools and machinery equipment like refrigerators, dishwashers, garbage disposals older EM pinball games, soda machine compressors, various lighting equipment at bars/clubs. Most power conditioners can't block and filter out all these different types of noises, harmonics, imaging harmonics frequencies, which get passed through into the guitar pedals power supplies. What would you recommend using to fix this problem when using very dirty AC outlets? use an AC isolation transformer but what else. If you look at the older guitar pedals power supplies its rating says for 115vac so if the AC outlet is 120vac or 125vac or 110vac the power supply transformers primary winding was not designed for other than 115vac so the transformers primary inductor winding will resonant because you can put your hand on the transformers Core and feel it vibrating. This causes the guitar pedals transformer primary winding to have a prematurely lifespan plus it induces noises and harmonics riding on the secondary winding because of the design of the primary windings was meant for 115vac not for 120vac, 125vac or 110vac.
JAMES LEBIHAN, All linear power supplies and Switching Mode Power supplies need to use an external AC power conditioner unit to block and filter out AC line frequencies other than 60 cps, harmonics, spikes, surges, noises from power tools and machinery equipment like refrigerators, dishwashers, garbage disposals older EM pinball games, soda machine compressors, various lighting equipment at bars/clubs. Most power conditioners can't block and filter out all these different types of noises, harmonics, imaging harmonics frequencies, which get passed through into the guitar pedals power supplies. What would you recommend using to fix this problem when using very dirty AC outlets? use an AC isolation transformer but what else. If you look at the older guitar pedals power supplies its rating says for 115vac so if the AC outlet is 120vac or 125vac or 110vac the power supply transformers primary winding was not designed for other than 115vac so the transformers primary inductor winding will resonant because you can put your hand on the transformers Core and feel it vibrating. This causes the guitar pedals transformer primary winding to have a prematurely lifespan plus it induces noises and harmonics riding on the secondary winding because of the design of the primary windings was meant for 115vac not for 120vac, 125vac or 110vac.