nxv300 R2 kit modification.

[ze froggy]

hello anthony,
just a little post to show you a modification to simplify
the trim of the idle current. i do this on my 6 modules .
my next modification is to reduce the amp gain to 26db.
in your opinion, should i reduce R24 (33k) or put a pad
on the bal input of the module?
i use four of them with a Minidsp 2X4 bal modul to built a
stereo 2 ways active, powered with 2 SMPS 2x72V 800W.
sound great, very low noise, good dynamics, very happy
with your amp .
thank's from France.
Manu
View attachment img-619133622.pdf

 

[The Saint]

Hi Manu

To reduce the gain just change R24 to 18k ohm 0805 for 26db gain
Great to hear you like the sound quality of the nxV300 R2 modules.

Post some photos of your amplifiers?


Cheers

Anthony

 

[ze froggy]

hello,
thanks for your reply,
will replace R24 with a 18Kohm, it"s more simply.
what do you think about the idle trim modification?
the first time i try to bias the current, i turn slowly cw
the pot, reading the voltage accros a 10 Ohm in the
PS rail, read 0v, 0v.....0v( middle position),continu to turn
0v, suddenly "over" on the voltmeter(2v range) approx at 3/4
of trim position.very difficult to reach 1v with a very small
debatement of the pot.
do this with 2 modules and read the value for a correct current
(approx 50ma per transistor)=around 105 Ohm.
so decide to transform the bias circuit for more easilly and accurate
setting.
the four modules are assembly on a cooling tunnel with a
thermally controled fan, and a switch off of the PSU over 90degresC.
i"ll post photos soon.
regards
Manu

 

[ze froggy]

hello,
some photos :
the modules on the heatsink!