fuses - the $39 ones or the 85 cent ones

Tbg,

On my HiFi-Tuning fuses, the logo itself has the arrow. I couldn't decide for myself either on which direction to go since I couldn't tell for sure the sonic difference between the two ways.

Isanchez, thanks!

Isanchez, I wonder why they stopped saying they were not directional.

Tgb,

I wasn't aware of the directionality issue until I read it here. So I don't know if the direction of the fuse was an intended feature for HiFi-Tuning fuses, or it just happened to be that way.

It seems that the Isoclean were intended to be directional.

Bgordon- Try the AC line fuse first, and if your system/room/ears resolve a difference(that you like), then try the DC rail fuses. Any improvements that one can make in the power supply of their amplifiers should provide a sonic gain. The power supply is what drives your speakers, whether modulated by transistors or tubes, as directed by the music signal. That's the fuction(power supplies) for which Hi-Fi Tuning, Isoclean and Furutech fuses were designed, and hence- where they will work best. Of course they're not just for power amps, but any audio gear with a power supply.