amplifier longevity

ARC D400MKII going on 29yrs and still kickin azz!

One never hears one ask what the amp sounds Like

I’ve gone  through five amps this month

class d

class ab

class A

tube and SS

v v hard to tell difference 

major conclusion- it’s the quality of the recording!

that a mess

Typically, the most reliable amplifiers are class AB or D SS devices, which are kept ON all the time and which has UNREGULATED big iron SIMPLE power supplies. The reasons are:

- Heat is the number one enemy of any electronics. Class AB and/or class D generates very little heat when there is no input. Minimal quiescent bias currents. Valve amps lose out in this area.

- Keeping it on continuously ensures that the amp does not experience inrush currents, which MAY reduce the reliability of power supply capacitors.

- Unregulated simple power supplies are the MOST reliable power supplies. When SMPS comes into play, reliability will be less.

All the above are more easily achievable in an SS amplifier. So, all things being equal, SS amplifiers are likely to be more reliable.

I've had my Quad 405 power amp for 44 years. Other than having it recapped 3 years ago, it's been 100% reliable. . 

I have a 46 year old GAS Ampzilla and a 41 year old Conrad Johnson MV75A-1 amplifier, and both work and sound great after heavy usage over the years. Both amps have been recapped only once, and the Ampzilla has had all of its driver and power transistors replaced.

Good stuff lasts. The new power transistors in the Ampzilla are 20 amp rented Toshibas vs the original 15 amp Motorola’s. Parts in most, but not all cases can be swapped out. I also have a 30 year old, never been repaired Adcom GFA-535 II in my bedroom stereo that still sounds great.