Synergistic Research Master Fuse
REFERENCE AUDIO – WITHAM ESSEX
BOB’s Review Series - No 90 – SYNERGISTIC RESEARCH QUANTUM MASTER FUSE 13 AMP
INTRODUCTION TO THE MASTER FUSE
Would you buy a mains fuse that costs £600? You could spend more, much more but currently the Master Fuse from Synergistic Research (SR) is top of their range, and they describe it as “the one fuse to rule them all’. Let me explain why I think you should consider buying a Master Fuse, but first what is a Master Fuse and why should it improve your system.
SR make Master Fuses for many different applications including internal slow and fast blow fuses from 50mA to 800mA values. I chose the 13-amp UK mains fuse as the one to try first and to listen to in my home system. I must confess to already having SR 13-amp Purple fuses in all my mains leads that supply current to my equipment including the mains lead to my subwoofer, but I didn’t have a special fuse in the lead from the wall socket to my power distribution box, so that’s where I inserted the Master Fuse as this surely would bring the most bang for my bucks as it powers everything else.
Purple fuses have recently been replaced by Pink fuses in the SR lineup but I’m sticking with my Purple ones although a colleague tells me he thinks the Pinks are better. SR recommend using the Master fuse alongside the Purple and Pink ones because the Master Fuse does something different and works best in conjunction with their other fuses. They also say that you shouldn’t need more than one or two Master fuses in your system and recommend using them starting with source components such as CD player, streamer, turntable etc and then moving on to your DAC or phono stage before your preamp and then power amp. But remember only one or two are really needed in any complete system provided other SR mains fuses are used elsewhere as they are designed to complement each other’s capabilities. SR also suggest that using one in the lead from the wall to your power supply block is a good place to start provided Purple or Pink fuses are used elsewhere.
SR say that prior to the development of the Master fuse they were not able to cater for full resolution, dynamics, sound staging, speed and impact without the need to use them in a full system wide fuse loom. The Master fuse overcomes this need, hence SR suggesting that only one or two will be needed, provided Purple, Pink or Orange fuses are use in the rest of the system. As with many SR products understanding the theoretical technology behind the design of those products can be a challenge and, in this case, SR describe their Master fuse technology as “having isolated the factors that affect how electricity propagates by changing the behaviour of electrons through inductive quantum coupling methods”. They call this UEF Tech. Any the wiser? No, nor am I, but let’s have a listen anyway.
CONNECTIONS
I’ve mentioned in earlier reviews that I use mains cables from HB Labs to feed power from the wall socket into my Gryphon PowerZone 3.10 mains block and from the PowerZone to my Gryphon Essence preamp, elsewhere all other mains cables are by Jorma Design. Those HB Labs cables are well worth seeking out as their design, construction and sound quality is better than most alternatives out there and their in-house designed plugs and sockets are some of the very best available. However, neither of my HB Labs cables came with a high-end mains fuse fitted, so I substituted the fuse in the lead from the wall socket for the SR Master Fuse. These fuses are directional and should be installed with the writing going in the direction of the electricity in your mains plug or internal wiring.
LISTENING
SR say their Master Fuses need time to run in, SR say 200 to 300 hours and I can confirm it did get better after 50 to 100 hours use, hopefully improvements will continue.
We all have favourite tracks and albums and some of those I’m sure will start just fine but get a bit tiring as the track develops and volume increases and everything comes together in a crescendo. I can think of several albums and tracks that have this glare and after listening to the system with the Master Fuse installed after an initial 100 hours running in it occurred to me that these tracks were now sounding much better throughout with those awkwardly bright crescendos tamed. This was not done by smothering or smoothing out the brightness and reducing fidelity, rather it was achieved by giving more coherence to the entire track, bringing instruments together rather than having them seemingly fighting each other for domination. A little difficult to describe exactly what I mean here until you hear it in action, but the whole system is sounding warmer, smoother and more inviting without losing anything at the top end. Detail if anything is improved and there is the feeling that every part of my system is working better as a cohesive whole rather than a selection of assembled components.
If you are a user of Roon you will know that on many tracks it can provide the lyrics, and mostly it gets this right but sometimes it gets it bizarrely wrong. Listening to Lucinda Williams “West Memphis’ from her album ‘On Down Where The Spirit Meets The Bone’ is an example of the latter. This album dates back to 2014 and was recorded at a time when admittedly her voice was starting to lose its edge and sometimes it can be hard to hear exactly what she is singing about. As my system has improved over the years an increased level of clarity and definition has helped understand her lyrics to the point now with the Master Fuse installed, I can hear exactly what she is saying. I’m not sure how Roon goes about finding track lyrics, whether it’s done by a real person of by some sort of AI bot but on this track she is singing about how justice is done in West Memphis, and she says ‘somebody got away with murder and a horrible offence’ and Roon thinks she is saying ‘somebody gone away with murder and a car full of fence’. I smile every time I hear it, and it gets worse as the track proceeds.
CONCLUSION
Well, I know at least two other people who have installed a Synergistic Research Master Fuse, and both are telling me that it has improved their listening experience. For me it's like having a significant component upgrade and all for just £600, for me there is no going back and it’s staying. Do I need another one? I’m not sure, but then I didn’t think I needed one in the first place. Perhaps I’ll try another one in due course and let you know.
I’m very impressed by the performance enhancement achieved with just s single SR Master Fuse.
September 2025
Bob – Team Reference Audio