Fosi Audio Box X4 Phono Preamp with JAN 5725W Vacuum Tubes for MM Turntable Phonograph Record Player with Volume Bass Treble Control

I needed a preamp because I couldn't do what I wanted with my existing setup. I had Fluance RT-85 turntable > Onkyo TX-SV575 (25 years old) > Rockville 21-band graphic EQ via Tape 2 monitor > Wharfdale Diamond 7.2 bookshelf speakers (also 25 years old). This setup sounded great, but I also want to have the music play in other rooms in perfect synchronization. I use the Wiim streaming device for this. The issue is that with that is that the sounds lagged a noticeable few milliseconds in the other rooms. The Wiim synch feature didn't work because the source setup didn't have the signal come from the Wiim. I need to change the order of the signal chain so that the turntable signal passed through the Wiim then to the receiver. And that's why I needed a pre-amp. After a night of researching solid state and tube preamps, I decided on the Fosi Box X4. I ordered it after 3am and it arrived before 6pm that same day (nice job, Amazon!). Set up was easy. The only odd thing was that the grounding post on the X4 is spring-loaded mechanism that seems intended for bare wire or a pin rather than the spade connector that is common on turntables. So I fed one prong of th fork into the opening and that works fine. The chain is now turntable > preamp > EQ > Wiim > receiver. This works but the sound seemed a little off. especially on older records. If I spent more time adjusting the EQ, I could probably get the sound to where I want it, but I'm lazy. Then it hit me, the sound out of the preamp to the receiver should be very good, so I set the EQ to direct mode which bypasses the adjustments of the EQ. I had to up the gain on the preamp after this since the EQ was boosting the level. Voila! That did it. Everyone is right that the X4 presents a wide and immersive soundstage. All the different pieces of percussion, acoustic and electric bass, piano, guitars, and vocals are all smooth and clear. I may keep this as the regular set up bypassing the EQ, and just using the EQ on tape and CD. This is my first tube set up, so I don't think I'll be making and tube changes for now. Definitely a great product, great performance, at a great price. I recommend it.

This was just what was needed in order to bring out the bass from the at-lp120x turntable that I got for Christmas. The turntable has a line out setting but it sounded tinny, could not get any solid bass from playback(all of the other playback devices did not have this issue). The tone adjustments work great and makes the adjustments easy. Only been using a few short days and I hope to get long term use of this wonderful piece of equipment.

The phono preamp sounds surprisingly great with every cartridge I throw at it. Plenty of detail, punch, warmth but not dull at all, with a nice quiet background, too. The tone controls are legitimately useful, with logically-chosen frequencies for a change. The X4 is worth the price for the phono preamp alone, imo. But the headphone output sounds boxy. It's tinny, lacking low end AND high end. It might come in handy if you need a basic monitoring function but that's about it. One other thing I don't like; the cheesy lights that make the tubes glow unnaturally. Totally unnecessary. They could have taken the money they spent trying to make this preamp more appealing to gamers and spent it on better circuitry for the headphone out.Overall I'd give the Box X4 2.5 overall stars because of the headphone output and fake lights. However, the phono preamp itself sounds SO GOOD that I have to up it to 4 stars. This preamp easily outperforms the phono preamps in my Denon receiver, my Denon mixer, and my Pioneer 250MKII mixer. If you buy it for that and not for the headphone amp I think you'll be pleasantly surprised if not shocked!

The media could not be loaded. It's a unique combination of tube phono preamp, component preamp + headphone amp and for the price it's ridiculously good value. My current amp has no headphone jack and with the X4, I now have the option to listen to vinyl with my headphones. It has plenty of power to drive my headphones to extremely loud levels. This preamp has bass and treble controls that allow me to adjust the sound heard through the headphones as well as the speakers - I never seen this feature on a phono preamp and love it.It came with 2 GE 5654W tubes. They are a very nice tubes and actually cost about $15 each, so that’s $30 of the value right there. One of the tubes had a slight bend in the pin that I had to bend straight to get it to fit in the preamp socket (typical problem with tubes…they are delicate). It has red LEDs that light up the tubes that make it look cool. The unit itself is built like a tank (solid metal casing). Attaching my record player to the preamp was simple and the sound quality is amazing! The sound using these tubes is rich and detailed and being able to adjust the bass and treble really lets me dial in the sound for different speakers. If you plug an aux cord into the unit, the phono preamp turns off and defaults to the aux input (gotta pull out aux and then the phono preamp comes back on).Overall I’m amazed at how good of a phono preamp this is for the money. The headphone and aux input preamp are just icing on the cake. Love this X4 phono preamp!!!