QSA 6.3 x 30mm Slow Blow Fuse
Who Knew Something So Physically Insignificant Could Sonically Transform Your Audio Components.
Tweek Geek Speek: QSA Fuses The New Top Tier Tweek
PLEASE READ:The process for construction of every QSA fuse is time consuming, and much work is done by hand. This process takes time and if order volume is heavy, that means you may have to wait. If your fuse is not in stock, it may take up to a month to receive it. Consider that before you order.
"...many high-end audio tweaks I've heard sound great, but none have matched the QSA's remarkable performance. I repeat, none." - Clement Perry, StereoTimes
"Same..." Mike Garner, Tweek Geek
Quantum Sciences & Their Philosophy
The Fuse: One Of The Biggest Bottlenecks in Audio Component Performance
- "This thing is amazing! Only 24 hours in but it sounds exactly as you and others have described. I’m thrilled!" - Evan S., Red fuse
- "After about 3.5 hrs listening, first 1-2 hrs Meh..2-3.5hrs these are SERIOUS fuses, Freakin Amazing at times!" Tom J., Violet and Black fuses
- "Just to let you know the fuse already arrived today!! I immediately installed it.The effect is fucking bonkers!!!I installed it in my Lampizator Pacific Dac with 300B’s Molybdenum tubes from Elrog ... This Dac has turned into a sonic beast! It was already super fast, but this is now a stereoid version of what it used to be... It’s insane, and completely what I hoped it would be. The money is heavy, but the sonic result makes it ‘almost’ cheap. " - Nico K., Red/Black Fuses
- "The clarity and quietness of these fuses is uncanny." - Chip F., Yellow fuse
- "Thanks for the amazingly quick ship on the new QSA fuse! If this is the 2nd from the bottom of their lineup, I can't imagine what some of the higher priced versions do. Installing this in my Decware Torii MK III was a revelation, and I had already tried several other after-market fuses!"- Chris P. Blue Fuse
"...$1422 each! That's crazy? I lamented, "This is just way too much to ask for a fuse, sir." Tsang's only response again was, "this fuse will outperform any tweak in your system. Looking at my components, I started taking an inventory. I've some serious tweaks in my space, namely the Novum Resonators, various Entreq ground boxes, Jack Bybee's iQSE Fatboys, alongside Kemp's AC conditioner and Frank Acoustics Ultra Bank products. All are excellent. None are cheap...
...Knowing the sonic improvements heard between the standard $28.50 Black series to the $711.00 Purple model, I admit, I wasn't sure what to expect. Insuring directionality, I just popped them in and just let the music play for the next 24 hours. Upon my return, I immediately noticed how much of a deafening silence had crept over the system. Weirder was this quiet did not affect the high frequencies negatively whatsoever. In fact, the opposite occurred. The top-end opened up with a sense of relaxation and ease, which aided a remarkable sense of brilliance. Bass was quicker afoot and possessed details that made me sit up and pay closer attention. Voices appeared more transparent but with more harmonic realism, flesh tone, and focus. Out of all these obvious improvements, the absolute lack of noise stood out the most. The top-end sparkle improved with more excellent sparkle, weight, and shimmer (yes, cymbals carry weight). All in all, the QSA Red series fuses introduced an altogether different sonic fabric that is rarely associated with digital sources and its playback - regardless of format or resolution. This, dear reader, is the magic of analog!..."Clement Perry, StereoTimes
What Reviewers Are Saying
Not one, but THREE Stereotimes reviewers have given QSA fuses their endorsement for 2020 Most Wanted Components. Read below to see what each reviewer had to say. Full Article
Quantum Science Audio Ultra High-End Fuse ($2,844 ea): "...Upon placing two of the QSA Red/Black fuses in each Behold amplifier (I have two amps which require two fuses each - plus an extra fuse for my preamp), I turned up some music and just sat there slackjawed. The room filled with sounds from the studio I never detected before. When cymbals hit, the rivets sounded like rainfall. WTF is going on??? The music developed a renewed sense of PRaT that it never had prior. The music began flowing out of my loudspeakers in a way that closely resembled the Audio Note gear in my downstairs rig. That's an 8-watt 300B SET setup and sounds ever so sweet and delicate. The upstairs rig is more like a 600 lbs gorilla - with wings: bigger and bolder, but with the same earmarks that relay the music in the purest sense of the word. These are sonic enhancements said to be impossible to achieve from solid-state components and digitally-based systems. Not True.
Quantum Science Audio Ultra High-End Fuse ($2844 ea): "... Once installed I could not believe the effect that took place in my system after a 24-36 hour break-in period. My system was currently functioning at an exceptionally outstanding high level. I thought any improvement in the sound, going forward, would be a small one. Boy, was I wrong! These tiny miracles allowed my system’s current significant attributes to expand beyond what I thought possible. Every characteristic we lovers of music hold important in sound reproduction became so much more pronounced. I’m delighted to say that at least four Stereo Times colleagues who now have these fuses in our systems have all experienced a similar dramatic result...this is one time where all of us who took the plunge feel it was well worth the cost. This is why I have chosen this QSA fuse as my 2020 Stereo Times Most Wanted Component. (Dan Secula)
What Customers Are Saying
The QSA Top of the Line Fuses
I have 4 components - Power Conditioner, Transport, DAC and Amplifier. All four have the Red/Black fuse installed. I installed the first three fuses six weeks ago and just installed the Amplifier fuse three days ago. My experience with burn in is interesting. After five weeks, the first three fuses were still improving the sound - still getting better every day (although it is decreasing). This is fun because the stereo sounds better every day even though I have done nothing. Of course the sound changes the most in the beginning; the first few hours it changes a lot. The same is true for the first few days - big improvement every day! Some highs (like a triangle or bell) didn't sound right for the first 2 days, but then they were better than ever.
- The Sound
- General Impressions
- Everything sounds more beautiful
- There is more emotion in the music
- Specific Impressions
- Much lower noise floor
- More micro-detail is revealed
- There is less glare (I didn't even know I had glare!)
- Individual voices and instruments are more apparent
- They don't blur together when massed together
- I think it is called individuation
- The soundstage is deeper, wider and higher
- The sounds are more solid in the soundstage
- There are no gaps in the soundstage
- Everything sounds natural
- Frequency Response is linear at all volumes
- Understanding lyrics is much easier
- Bass goes deeper than before
- Bass is better defined and easier to follow
The music just "pulls you in." You don't want to stop listening - very addictive.
These changes have been The single best tweak I have ever made! And I have been tweaking my stereo for 40 years.
We Stand Behind Our Words and These Fuses
We have been in business since 2003. We made our reputation on offering great advice, knowing our products, service, service ,service, and our 30-day money back guarantee. We stand behind the QSA fuses with this same 30-day guarantee. If you try one of these fuses and don't think it is worth the investment, simply return it in it's original packaging and condition, and we will refund you the purchase price. You have our word.
2 Reviews Hide Reviews Show Reviews
I have been listening to the QSA yellow fuses I ordered from you. These fuses are in my phono preamp (arc ph7), preamp (arc ref 3) and amp (arc ref 110). Speakers are martin logan summits. Although I do not have alot of hours on them yet I can clearly hear a difference. What I am hearing is a lowered noise floor which leads to more detail. In my system the most dramatic effect is being able to better understand the lyrics. The system sounds more relaxed and musical. The yellows replaced other aftermarket fuses ( high fi tuning in the preamp and Synergistic Orange in the amp. The QSA fuses are more musical and detailed. I am pleased with the cost /benefit ratio of these fuses since they cost only a bit more than the fuses they replaced. To put this in perspective I have retubed all 3 components this year with expensive, trick aftermarket tubes. I think the fuses made a greater improvement in the sound at 1/3 to 1/4 the cost, at least in the phono stage and preamp. I do not think this is true for the amp because I replaced the 6550 output tubes for KT 120s which was a greater improvement than replacing the fuse (at 5 times the cost of the fuse). I think the amp fuse did make the most improvement of the 3 in my system. While I am NEVER going to spend 2800 dollars for a fuse I am seriously considering taking advantage of your trade in offer to move up to the purple fuse for my arc ref 110!
Always skeptical that fuses can add much value. Fuse musicality? Nonsense! Until you discover Quantum Science. The Blue fuses in my mono block amps made a significant improvement in the detail and definition of piano and other stringed instruments. Improved imaging and broadened the soundstage. I was incredulous. They are the real deal! Recommend highly.