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First One - mosFET amplifier module

Few evening hours spent on the first serious listening session with the First One V1.2 from this group buy (exactly the ones from post #1) and can surely confirm that it is clearly over performances of the First One V1.1 from exhibitions presentations. Sound is a bit more refined, scarly realistic vocals, even greater insight into recording material and all of these in a very polite way. Completely satisfied with the result. :cloud9:

At this occasion I would like to express my gratitude to each and all of you, following this thread and also placing the orders, many thanks. :worship:
 

fab

Member
Joined 2004
Paid Member
Hi, look to post #13, all differences explained there. ;)

My guess would be an added driver stage between the VAS and the output.?...;)
I have already done that last year and used old medium Lateral MOSFET for the driver stage . The sound was good but I have damaged the amp and have not repaired it since then...

Your implementation is of course awesome . :up: Mine was done using modified boards with wiring....

Fab
 
Few evening hours spent on the first serious listening session with the First One V1.2 from this group buy (exactly the ones from post #1) and can surely confirm that it is clearly over performances of the First One V1.1 from exhibitions presentations. Sound is a bit more refined, scarly realistic vocals, even greater insight into recording material and all of these in a very polite way. Completely satisfied with the result. :cloud9:

Congratulations, that sounds very good. :)

I'm longing to hear them in my home :drool:
My audio system is ready for The First One :)
 
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I will place an order for a full kit for 2 channels , once it´s available , cause i hate looking for parts here and there .

I will go for a full stereo kit (amp modules, chassis, psu) if available.

OK guys, no problem, just a little patience for me to prepare the cases and SMPS-s. Please send an e-mail noted in post #1, so I will record the info and put you on the list. :up:
 
LazyCat,is it possible to buy modules in a later stadium or is it a only once in a life time oppertunity?

As I already explained in post #40, #45, there's no rush, nothing will be delivered before output mosfets received here and installed to PCB-s.

Regulary observe post #1 for the updated info, anyway you can send an e-mail just to have you on the GB list for the record. :up:
 
As promised yesterday here's the measurement result for 1 Wrms (2,83 Vrms)/8 Ohm at 1 kHz.

1. Input sine signal 0,11 Vrms, THD1k=4,8 ppm, best what I can get from the card's signal generator

2. Output signal 2,83 Vrms/8 Ohm, THD1k=16 ppm

As seen from plots, input signal artefacts generated by audio card faithfully transferred to the output plus some distortions added. With better input signal we could just get to single digit ppm. :cool:

Post #1 technical specifications updated according to measuring results. ;)
 

Attachments

  • Input sine signal 0,11 Vrms,1 kHz.png
    Input sine signal 0,11 Vrms,1 kHz.png
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  • First One 2,83 Vrms on 8 Ohm, 1 kHz.png
    First One 2,83 Vrms on 8 Ohm, 1 kHz.png
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Yesterday, Andrej (LC) finnally bring new First One amplifier prototype to my home. I am sure it is the best amplifier ever tested in my system and probably one of the best I have ever heard. It is huge step forward from VSSA in terms of space, less distorsion and completely loss of grain, which VSSA have a fraction of it ;)

Fantastic job LC :cool: