Why is No One Talking about this? Fosi GR40 Audiophile Dac and Headphone Amp

[@brianraulerson5037]

I have an older Schiit Lyr and Bifrost. I bought the Unison USB add-on for the Bifrost because the only inputs were coaxial and optical. So if you went with new pieces you would pay around $1500 and still not have bluetooth. The Fosi is on Amazon right now for $119. I think that most ears wouldn't hear $1380 worth of difference. The Lyr is more powerful and can power up to 600 Ohm headphones but I don't think a lot of folks have those. My DT880s are 250 Ohm and gobble power. Lastly, the folks at Tube Depot are really nice and helpful and have a great selection of tubes for your equipment. Fun fact: the "JAN" on JAN tubes stands for "Joint Army Navy" so they are literally military grade tubes!

[@Brian_Romska]

Ya this is pretty cool, I’ve got the little xduoo headphone amp, looks similar, and I always thought it’d be nice if there were something similar with a built in dac, and here we are, yay! I think I’ve got a coworker who might pickup one of these, which means I’ll end up getting a chance to check it out for free, so thanks! Always nice to see another vid, keep it up man!!!

[@Toid]

@@Brian_Romska nice! Good way to test it first

[@90sNintendoKid]

I love my v3 monos and I don't recommend that they are stacked like that. I've been reading forum threads and watched KZbin videos that show they have thermal problems which are easily fixed with a fan, which is why I run mine with a Fosi fan underneath.

[@Toid]

@@90sNintendoKid that’s great to know! Thank you!

[@quig4800]

Hey Toid .. Have you ever designed a 4" Full Range bookshelf speaker? THANKS for the great videos!

[@ecko80911]

Wish I would have found this video about two weeks ago. Just purchased the Fosi audio SK01 headphone amplifier equalizer preamplifier. Thankfully if there is anyone else looking they now have options.

[@Toid]

@@ecko80911 sorry. I actually wanted to have this out sooner, but I got sick.

[@ecko80911]

@@Toidno worries brother. Glad you are doing better. If I don’t like what I purchased I’ll buy this😂

[@danrussell9357]

@@ecko80911If you want tube harmonics, you can get a tube buffer. Fosi has a tube buffer stage in their phono preamp which makes sense since vinyl and tubes go together. I am guessing that you have a DAC already because you didn’t get the SK02 which is the SK01 with the DAC. If not, my guess is switching from a line source to a good DAC is a better improvement than adding tubes.

[@zarboaudioprojects1430]

It's a wonderful time to be alive! Competition is hot between these small form-factor amps, DAC's, pre-amps, etc. and it means several companies are constantly creating exciting and very good products for us to enjoy! Nice video Senior Toid!

[@danrussell9357]

The JAN 5654W is the best version of the 6AK5 tube, and if you roll tubes it will likely sound worse. Can you explain the difference between this amp and the Fosi P3?

[@Toid]

@@danrussell9357 I’m not real familiar with the P3, but I know that biggest upgrade has been the dac. They upgraded to an ESS audiophile grade dac.

[@danrussell9357]

Thanks for the reply. They revised their P3 tube headphone amp to give you those better tubes. I guess now that the DAC is upgraded there is enough change for a new name.

[@thelowprofile9767]

These Fosi units look like the counterpart of Klipsch in terms of looks.

[@Toid]

@@thelowprofile9767 haha! They really do!

[@mullinperformanceaudio5902]

Hmmm.....I see the problem. It doesn't go to eleven.

[@Toid]

@@mullinperformanceaudio5902 haha!!!

[@Peter-p7e]

👍😀

[@RoccoXYZ1]

Insering tubes in Fosi units is a nightmare. Forget abiut this so called rolling. I have ruined many tubes trying. Ridiculous. I have used tubes since 1964 and never has these problems.

[@familiekruit6068]

It’s extremely unlikely that those tubes are in the audio path and in the unlikely case they are it isn’t good. That amplifier simply doesn’t have the power supply to do anything useful with those tubes.

[@jordyvaneeken7462]

Hmmm....... Are you doing only rewiews nowadays? Only 3 videos about building stuff this year?! Please change your name to "Toids REVIEW Audio". Miss your DIY teaching days.

[@ericl7910]

Did you just touch a tube with your bare hand? I don't think that's allowed =)

[@familiekruit6068]

It doesn’t matter. Tubes aren’t halogen bulbs.

[@multicyclist]

My experience with them is I would not purchase another Fosi product (fake surface mounted 5531 op amps and substandard electrolytic capacitors). Not an honest company. Their products look the part only. They set it as a headphone amp because they are concealing something. Look at the horrible frequency response. Can the tone controls be adjusted flat? Nope.

[@Toid]

@@multicyclist just for clarification the frequency response is a set of speakers of known response. The response of the unit was linear.

[@multicyclist]

@Toid Noted, my bad. On my Fosi phono tube preamp with tone controls, there is no way I can obtain a flat response by adjusting the tone controls. Therefore, I am unable to verify if it has the correct RIAA curve but it is doubtful. The volume pot is not even audio taper. The two surface mount 5531 op amps used in the tone circuit are counterfits. Real ones have protection diodes on their input pins and one can easily verify with an ohm meter. These are missing, meaning they are likely a ($.40) 741 or similar type of low-grade componet. If someone likes it and is happy, that is totally fine, but the Fosi phono preamp I have is not usable and has been relagated to a junk bin.

[@stefanweilhartner4415]

hipster bs