My Musical Fidelity A5 CR Power Amplifier one day went “Pop!!!” and smoke started emitting from the unit! and tripped all the electric out in my house! I stupidly took the unit to a local repair guy (who has a shop!!!) who diagnosed fault as “Tordial Transformer gone, cant get parts, could maybe make one!” A costly lesson for me, he had taken the transformer out cutting it from the circuit board and unwrapping it! I then found John online and he rang back straight away. Even though John did not have the unit he seemed to know several things it would be straight away and said it was very unlikely to be the transformer. After reading the testimonials I decided to send the unit to John. Next day John called with a full diagnostic, quote and service/upgrades available with no hard sell, just professional information about what it may improve. I decided on full service/upgrade. 10 days later I had the unit back on my rack and looking like new! now that’s service! I’ve left reviewing for several weeks as the sound has took a while to settle and has sounded better every day. Sound improvement from Johns expertise are a much larger than any upgrade Ii have added to my gear for less cost. Now just so musical, 3-D soundstage that is so detailed and lifelike it is quite spooky on certain records! The power, tightness and tunefulness of the bass and the depth of soundstage are massively improved. At times I feel like the bass goes through the floor, and I have my speakers spikes on concrete plinths! John Sampson Is a professional that obviously cares about his customers’ and their hi-fi units and can service your components to function at their optimum (not held back by corners cut in manufacturing costs). I would have absolutely no hesitation in recommending John and am considering sending future units to him when funds allow! Go for it – you will not regret it!