100W Ultimate Fidelity Amplifier

hi stewin, if you want build FX-8, I have few boards and can ship 2 you free, I dont need them because amp is built and rest of boards are not used ...

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Founder of XSA-Labs
Joined 2012
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That's the FX8 Bimo mod - very nice. I just connected my FX8 Sonal 50mm x 50mm edition last night. PSU is the Project16/Prasi CRC board followed by a low ESR 20x1000uF cap array. Replaced the ceramic input cap with a 10uF 35v Elna Silmic II. Listening to it all day now. Very sweet sound. Surprisingly powerful for such a tiny amp.
 

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Founder of XSA-Labs
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Interest in FH9HV GB kits?

In the past month I have had 3 requests for the FH9HV amp PCBs or even better, members were asking for full kits with all components included. It's a great sounding and very easy to build cost-effective amp, and with the HV upgrade allows 50v rails for a 125w class amp. I have seen several positive comments from members on this thread who liked it. Anyhow, if there is enough interest I could organize a group buy on the FH9 amp in another thread.

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few people asked for them, now all PCBs are reserved, tomorrow or after weekend I ship them ... happy building (and give here review after build)

Hi miro1360,

Thats great!.
I hope Mr. stewin gets his pair. I like it when charity is shown to a genuine DIY'er.

I have been helped in my DIY efforts though charity by many kind souls, in the beginning.

If I remember correctly, in amp showdown by xrk, FX-8 Bimo-mod is nearly equal to the top contenders, a very Hi-Fi sounding amp was the result (if memory serves right).

Correct me x , if I am wrong.

regards
Prasi
 
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FX8 bimo mod vs FH12 ... it is fast the same but FX8 is little more deeper in lows (in equally volume level), and with FH12 you can get more power on output - but so much power you dont use for home speakers, for home speakers is better to stay with FX8
I have not built nx12 so I cant compare this one ...
Prasi did nice job with his PCB for FX8 :)
 
FX8 bimo mod vs FH12 ... it is fast the same but FX8 is little more deeper in lows (in equally volume level), and with FH12 you can get more power on output - but so much power you dont use for home speakers, for home speakers is better to stay with FX8
I have not built nx12 so I cant compare this one ...
Prasi did nice job with his PCB for FX8 :)

Thank you. I have FH12 mod too :)
If I have time I will make some modification of other Apex's amplifier (in simulation). I hope Prasi will make the layout.
 
Just for curiosity's sake, why do you feel you need to make modifications to Mile's designs?

I love the idea of Mile's design, but my optimization may be different from Mile. I like high slew rate and low THD amplifier. If you ask Hugh Dean (AKSA), may be he change the design to have H2 distortion dominant or have monotonic harmonic profile.