Fosi Audio Box X5 Phono Preamp Review

[StevenSGT98]

The difference between 'real' and 'imaginary' is a pretty valuable, no?

And again: this ain't Audio Impressions Review. We at least nod to the rigors of science. At minimum this simply means acknowledging you could be quite mistaken.

I’m a photographer by trade with a previous life of offset printing. There is not only the science, but also the engineering and application of the science. As I print, color science - including color profiles for every device in the printing chain is essential to producing correct prints. These are created by very precise measuring devices. The results are quite accurate - and here is the rub - as long as the viewing conditions are optimal. If viewed under the wrong lighting, the color can be way off.

The same for audio. Unless everyone has optimal listening rooms, the sound will be off. There is only so much that can be “profiled out” by REW or another measurement system. There also may be more ambient background noise than what the system can overcome. Or it may be more live, or dampened. One rooms “correct” does not fit another either.

Does this invalidate having the calibration standards? In no way. It is essential to get close to “reference.” But almost no one’s room is perfect.

At some point we step back and enjoy the art with what we have.

 

[StevenSGT98]

To me the Waxwing sounds more analog than analog.

Funny comment but very true.

I always start out with the sceince to narrow things down, once I have a group then I might get a bit subjective. Works well for me.

Same for me, and I think a lot of us here.

It's a swiss army knife of solutions. I admit I did almost avoid it, not because it's digital, it was due to it being the first of it's kind made by a one man show right down to the programing. In my mind and so often true, don't buy the first of anything that is a radical change from the norm, wait for improvements, it's rare somone nails such a unique unit on the first try (I know, the Puffin, to me the same as the Waxwing but easier to use).

Magic is great for casual listening. But for the purists it’s probably heresy. Grading is kinda interesting. The cartridge alignment tools actually are quite helpful. I hope Shannon does some kind of future proofing for his business, but for now his business model is very open, which I find refreshing.

 

[clapp1115]

Added the x5 to my Wiim Amp Pro; paired that with a vintage table running a Shure M91ED cartridge and some vintage acoustic research speakers, everything sounds great.

 

[Nicholas B]

I too, have now added the X5. It is fed by an AT-LPW50PB record deck that has an AT-VMN95ML cartridge. I have used RCA leads between the record deck and the Fosi that measure only 15pF (~ five inch length - Fosi is suspended behind the deck). AI tells me the tonearm wiring has about 20-25pF of capacitance. So, not more than 190 pF all up, thus I meet the AT recommended capacitance of less than 200pF.

Sounds good and works well with gain set at 38 dB. The 240V to16V AC transformer doesn't make a sound, so all good on that front, too .

 

[mtcn77]

Happy 2026! Just ordered my Fosi Audio X5. I'm so lucky it was just in sale.
PS: Omg, this is amazing! No noise of any kind. I'll leave some room, however the bass and highs are clear as cds.
I hear just some rumble, however my Reloop doesn't rumble too low, 28-56Hz, nothing to be afraid of.

 

[mtcn77]

LOL! Right as I plugged it, 1 day later my Klipsch active speakers broke. I'm back to my Sony MHC-VX333. Couldn't be happier.

 

[Jiří Barta]

Project rpm9/Ortofon Quintet blue into X5 into Topping pre90/b200/ Canton reference 7k sounds great, close to digital if good pressing provided . Compared to aging dual mono Clearaudio Symphono+ (20plus years ago priced at cca 1000euro) Fosi wins in what I hear here.

 

[Shotgun Rico]

This is my first post here. I read through this entire thread because of the great rating this preamp has. I was fortunate enough to try this preamp out recently so I thought I would give my thoughts. I grabbed one on Amazon and it had an issue where the right channel was not working so I sent it back for a replacement. The second one I received came in fine and was working properly. While this pre is incredibly clear and transparent I thought it was a bit thin sounding. The low end especially bass guitars sounded a little subdued in my opinion. My other pre is the Fosi audio X2 tube preamp with the Jan 5654W tubes from Riverstone Audio. If I didn’t have the X2 and if the X5 was my first pre I would definitely keep it. But I like the sound of the X2 with the tubes so I will be keeping that until I find something else. I think I will save some money for the Waxwing and give that a try in the future.

 

[Laika2]

This is my first post here. I read through this entire thread because of the great rating this preamp has. I was fortunate enough to try this preamp out recently so I thought I would give my thoughts. I grabbed one on Amazon and it had an issue where the right channel was not working so I sent it back for a replacement. The second one I received came in fine and was working properly. While this pre is incredibly clear and transparent I thought it was a bit thin sounding. The low end especially bass guitars sounded a little subdued in my opinion. My other pre is the Fosi audio X2 tube preamp with the Jan 5654W tubes from Riverstone Audio. If I didn’t have the X2 and if the X5 was my first pre I would definitely keep it. But I like the sound of the X2 with the tubes so I will be keeping that until I find something else. I think I will save some money for the Waxwing and give that a try in the future.

Big fan of the Fosi X5, I had to turn the gain down and rase volume to get solid bass. That said sounds like you have a better plan. Im running two Waxwings now I was so impressed with the first. Things are a Swiss Army Knife, not enough bass, adjust it with your phone and hear the change in real time, amoung endless other features.