Audiofun hit the nail on the head about the AMR fuses. I put the AMR fuses in my amp and noticed a considerable improvement in sound quality and tonal texture. As "boutique" fuses go the AMR's are a steel at their price point. I think I paid in the $20-$25 range from Avatar Acoustic. Darren and Bonnie Cencullo are great people to deal with, drop them an email or phone call you'll be glad you did.
Chris
Chris