??? Fuse UpGrade??What Size???


 In an effort to maximize the potential of my SimAudio Moon 240i integrated amplifier I have decided to try one of the Synergistic Research Purple fuses...
 The owners manual states it uses a 4 amp,Fast Blow,Type AG fuse..
 However,there are 2 sizes of this fuse offered,5mm x 20mm & 6.3mm x 32mm..How do I determine which size I need? Pulling the old one out & measuring it comes to mind but I was hoping there is a faster way to determine this...
 Thanks very much for any assistance..

freediver

I recently upgraded my fuses for my Shindo Mr T,Aqua LinQ transporter and Weiss 501 MK2 for the Pink fuses and after experimenting with the right direction and between 100-200 burn in time,I can hear a very noticeable difference with the soundstage(,wider and higher),Instrments and voices are more detailed and airy and the overall sound is more live. I also recently bought a Rel S510 sub and Wow! It was probably my biggest upgrade. I know adding a second sub would complete the 20% on the 80 % upgrade but I live in a condo with neighbours downstairs so 1 is satisfying for me, should have done this years ago.

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IME the Vera-Fi Audio SDFB outperforms any aftermarket fuse on the market. Many excellent reviews here & elsewhere. Email Mark with any questions. He's very responsive. 

I can vouch for the Synergistic fuses, I was skeptical, put one orange in my amp... Then I had to do every fuse, my preamp, my DAC, my streamer now all have SR fuses. Some really good snake oil that adds warmth, analog, real sounding performance value.

Now for the rest of my life I'll have to always buy these things because I couldn't have a 50¢ cheap fuse be the weak link in any component going forward... 

I'd use a pure copper penny to get the best sound. Pre 1982. (pssst, fuses make ZERO) difference in sound).