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First One - mosFET amplifier module

Getting more and more impressed with FO 1.4, nice :)
And I only have them 10 hours playing.
I noticed that I hear more details, especially in the low mid compared to my F5.

With foobar on pause and volume on max my speakers are dead silent with my ears at 1cm from the drivers. Very deep black noisefloor :)
 
Low distortion and perfect grip will cause you to crank up the volume next, for sure...

You may want to try (and all that are stuck on Windows) the best (by far) player I've used:

Bug head

Scroll down for the free download link. It will take you a moment, though it is a bit tricky to understand at first, but believe me, it is worth every second invested. :cool:

Good luck.
M.
 
Special Ag wiring edition First One v1.4 in assembly for my friend audiophile. :)
 

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Getting more and more impressed with FO 1.4, nice :)
And I only have them 10 hours playing.
I noticed that I hear more details, especially in the low mid compared to my F5.

With foobar on pause and volume on max my speakers are dead silent with my ears at 1cm from the drivers. Very deep black noisefloor :)
First Post of this thread shows:

Signal to noise ratio
> -110 dB

So it is, dead quiet. PSRR is in the same range, clever circuit enabling use of unregulated SMPS or conventional PSU, no mains frequency present in the spectrum and all that with just two electrolytic capacitors present on the PCB. Also very future friendly when recapping will be needed. :nod:
 

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First Post of this thread shows:

Signal to noise ratio
> -110 dB

So it is, dead quiet. PSRR is in the same range, clever circuit enabling use of unregulated SMPS or conventional PSU, no mains frequency present in the spectrum and all that with just two electrolytic capacitors present on the PCB. Also very future friendly when recapping will be needed. :nod:


Cant wait any more! ;)
 
Installed second SMPS Yesterday and LC is right ,it is ok with one,but now Imaging,Separation is better and it is like Musik is getting away from the Speaker. I like it.And another Thing is,it is dead Quit now.
Regards DT
Thanks a lot for the info Dirk. :worship:

All present here can finally believe me, just copy paste what I show and preach all along this thread and you'll get a real music at your home. :nod:
 
Another Black Mamba hit the road

Some more pics of today's finished First One in Black Mamba chassis. :cool:

Super PM-audio silver/teflon wiring - special edition for my friend. :cool:
 

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Hum - Need input on wiring

I completed the First One chassis and wiring, confirmed the settings, and connected inputs and speakers. It is a two channel amp running on +/- 55VDC from a linear supply as shown. Sounds great except for a low level hum coming through the speakers that does not vary with volume. The hum only occurs when BOTH inputs are connected. I have tried two sources (MiniDSP 4x10 and Samsung S5) and both result in the same hum. If I disconnect the left or right input, the hum disappears completely.

My wiring diagram is attached. I have shown one channel, but they are both wired the same way. The only electrical connection to the chassis is the earth from the mains wiring.

Any suggestions?
 

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