Apologize if this has been discussed previously; a search for "LED replacement" had 0 results, so here goes. Last year I had my 112 tuner in for repair. Opted to change the front panel lights from the original fuse lamps to LED for all main indicators (dial, signal strength). The result can only be described overall as a strong blue (Sapphire). I do like it. But, I was then considering the the same change to LEDs for my 4140 amp. This, to me, was a Big Step. I've owned this amp since 1977 and am reluctant to make any design changes. Of course if a cap or resistor goes out it will be changed with the original or closest replacement, but changing the fuse lamp design to newer technology? I made the decision to keep the original design and just refresh all the fuse lamps with the original 200mA fuse lamps. The resultant color is what I'd call "Mediterranean Blue" or aqua. It's definitely much softer than the LED blue on the 112 tuner next to it, but I'm sticking with it for now. Appreciate any +/- on changing to the LED option for this amp, thanks to all.