A few days ago I installed two Hi-Fi Tuning fuses to each of my Maggies 3.6. The Maggies 3.6 use a 4 Amps fast blow fuse to protect the mid-range driver and a 2.5 Amps fast blow fuse for the tweeter. The fuses are mounted between the crossover and each driver following the signal path. So the signal passes through the fuses and they also get all the vibrations from the speaker frame.
I did a shootout between the following fuses:
Hi-Fi Tuning ceramic fuse, $39/each.
Littel Fuse glass fuse, $2/pack of 5.
Radioshack glass fuse, $2.99/pack of 3.
Buss Fuses ceramic fuse, $6/pack of 5.
All the fuses are UL Listed, except for the Hi-Fi Tunning one.
In this particular application, the ceramic fuses performed better than the glass fuses. The overall difference is that the sound coming from the mid-range driver and the tweeter driver is cleaner with ceramic fuses than it is with the glass fuses. For instance, piano notes sound more consistent with the ceramic fuses.
The Radioshack fuse produced a slightly cleaner sound, but the clear winner by far is the ceramic fuse made by Buss Fuses @ $6 per pack. There is a more coherent presentation with this fuse. The mid-range has more weight and the highs are a lot cleaner.
I was quite surprised that the much cheaper ceramic fuse performed better in this particular application. This makes me believe that the Hi-Fi Tuning fuse is simply a scam. In the case of Hi-Fi Tuning, you're basically paying for the printing of the logo on the fuses, selling the fuses to a distributor, which a the same time sells the product to a reseller. This process seems to cost $39 to the end user.
My suggestion is go to mcmaster.com and get the cheap ceramic fuses from them, or any other supplier, and save the money to buy some music.
After a long listening with the cheap ceramic fuse, I inserted the Littel Fuse glass fuse and I could only listen with this fuse for 5 seconds. The cheap ceramic fuse is here to stay.