For all the going around online on the op-amp debate, I can honestly say that these 2 little op-amps make a huge difference on my system and I can honestly see why people like these.

It opened up my space and gave me a different sound than the stock one. I have also gotten the Burson classic that I also love, and my next test is going to be to put the Sparkos on the XLR side and then the Classics on the speaker side of my ZA3 and see what happens hahahaha

I love modern HiFi :)

For all the going around online on the op-amp debate, I can honestly say that these 2 little op-amps make a huge difference on my system and I can honestly see why people like these.

It opened up my space and gave me a different sound than the stock one. I have also gotten the Burson classic that I also love, and my next test is going to be to put the Sparkos on the XLR side and then the Classics on the speaker side of my ZA3 and see what happens hahahaha

I love modern HiFi :)

Ok, no joke these things sound AMAZING I love the way they change the audio. I got the Burson Classic and having also gotten an all Fosi system with amp speakers and sub I can safely say that they made the system sound just incredible, warm, almost like I got a completely diferente setup and all I did was install the op-amps. I don’t know if it’s better sonically or detailed or more realistic or whatever audio files will say, I can just tell you I like the sound better now and it makes me feel the sound not hear the sound if that explains it. Ok enough as like I said from the title, I don’t want to sound like they are paying me to say this or I’m getting something out of it. These things are awesome period. Cheers

Ok, no joke these things sound AMAZING I love the way they change the audio. I got the Burson Classic and having also gotten an all Fosi system with amp speakers and sub I can safely say that they made the system sound just incredible, warm, almost like I got a completely diferente setup and all I did was install the op-amps. I don��t know if it��s better sonically or detailed or more realistic or whatever audio files will say, I can just tell you I like the sound better now and it makes me feel the sound not hear the sound if that explains it. Ok enough as like I said from the title, I don��t want to sound like they are paying me to say this or I��m getting something out of it. These things are awesome period. Cheers

Very Good Quality Product

Very Good Quality Product

No fakes here. Great sweeter sound after installing in my V3 Monos

No fakes here. Great sweeter sound after installing in my V3 Monos

FOSI ZD3 OPAMP를 MUSES02로 교체 기계적인 소리가 감성이 있는 소리로 바뀌네요.

FOSI ZD3 OPAMP? MUSES02? ?? ???? ??? ??? ?? ??? ????.

I know this is one of those polarizing subjects, but as a 30+ year audio engineer, producer, technical director and mastering engineer, I can tell you that I can hear a difference. And with the Sparkos especially, it’s good. I have a pair of Burson V7C inbound so I’ll write that one when I drop them in. I have replaced the SE input op-amps in all three of my V3 Monos and my ZD3. All at different times and used with various rigs I have on hand and the difference with the V3s is not as subtle as with the ZD3. Both exhibit better dynamics, more pronounced separation and improved top end clarity and holography. Fosi has really created something special in their line up of DAC, Apms and Preamp with dip8 sockets. People can get into a great sounding high quality HiFi device at an unbeatable value, and then upgrade that device as they can afford. Fosi has the HoFi establishment on notice and it’s not difficult to hear why. I’m a huge fan.

I know this is one of those polarizing subjects, but as a 30+ year audio engineer, producer, technical director and mastering engineer, I can tell you that I can hear a difference. And with the Sparkos especially, it��s good. I have a pair of Burson V7C inbound so I��ll write that one when I drop them in. I have replaced the SE input op-amps in all three of my V3 Monos and my ZD3. All at different times and used with various rigs I have on hand and the difference with the V3s is not as subtle as with the ZD3. Both exhibit better dynamics, more pronounced separation and improved top end clarity and holography. Fosi has really created something special in their line up of DAC, Apms and Preamp with dip8 sockets. People can get into a great sounding high quality HiFi device at an unbeatable value, and then upgrade that device as they can afford. Fosi has the HoFi establishment on notice and it��s not difficult to hear why. I��m a huge fan.

Picked up a ZA3 and decided to roll the amps on a center channel for home theater use. What a difference they make!!! Sounds are very natural and can't describe how much better it sounds. At first didn't notice much of a difference but after sometime the amp really starts to open up and give u a totally balanced sound. Price might be a little steep at first but in the long run they are worth it. If your on the fence give them a try and you'll really not regret it.

Picked up a ZA3 and decided to roll the amps on a center channel for home theater use. What a difference they make!!! Sounds are very natural and can't describe how much better it sounds. At first didn't notice much of a difference but after sometime the amp really starts to open up and give u a totally balanced sound. Price might be a little steep at first but in the long run they are worth it. If your on the fence give them a try and you'll really not regret it.

In one room I have a Wiim Ultra going into Fosi P3 then two V3 monos running Sparkos op amps with excellent results.
In my main listening room, however, I was running a Schiit Modi 3 DAC into a Sansui integrated amp AU-7700. I used the Sansui as a preamp (via preouts) that lead to my Adcom GFA-5500.
I swapped out the Schiit for the Fosi ZD3 with a Sparkos op amps and got that wonderful imaging and soundstage with the vintage equipment that I was getting with the dual monos.
Thank you Fosi and Sparkos for breathing new life into my beloved vintage equipment.

In one room I have a Wiim Ultra going into Fosi P3 then two V3 monos running Sparkos op amps with excellent results.
In my main listening room, however, I was running a Schiit Modi 3 DAC into a Sansui integrated amp AU-7700. I used the Sansui as a preamp (via preouts) that lead to my Adcom GFA-5500.
I swapped out the Schiit for the Fosi ZD3 with a Sparkos op amps and got that wonderful imaging and soundstage with the vintage equipment that I was getting with the dual monos.
Thank you Fosi and Sparkos for breathing new life into my beloved vintage equipment.

I was curious about the change these will cause to my ZA3 (already good sounding amp). I must say I noticed immediately the change in bass, detail and sound spatiality. I am planning now to get a couple more to mod some other devices I have lying around and not used because I grew bored of the flat sound those have. My actual setup is a wiimpro feeding Qobuz to a Topping DX9, then coupled to ZA3 and Monitor Audio Silver 500. As headphones Im enjoying mostly Hifiman Arya Stealth V3 and the Organics version when using a fiio dap.

I was curious about the change these will cause to my ZA3 (already good sounding amp). I must say I noticed immediately the change in bass, detail and sound spatiality. I am planning now to get a couple more to mod some other devices I have lying around and not used because I grew bored of the flat sound those have. My actual setup is a wiimpro feeding Qobuz to a Topping DX9, then coupled to ZA3 and Monitor Audio Silver 500. As headphones Im enjoying mostly Hifiman Arya Stealth V3 and the Organics version when using a fiio dap.

I bought these opamps to put in my Geshelli J2S DAC and will buy them again for the ZA3. I'm no audiophile, so I won't try to describe the sound difference. I have one Sparkos Labs SS3602 in the XLR slot in the ZA3 already.

I bought these opamps to put in my Geshelli J2S DAC and will buy them again for the ZA3. I'm no audiophile, so I won't try to describe the sound difference. I have one Sparkos Labs SS3602 in the XLR slot in the ZA3 already.