I'm putting this up as a place holder for the new nx2-Amplifier (hereinafter just called the 'nx2') which has been in gestation for some 15 months now. I've had quite a few nudges from various people via email asking about progress. I can understand that some folks have fallen into believing the nx2 is 'vapourware' (if you've worked in semiconductors or software product development, you'll now what that means!).
I started work on this in September 2023, assembled the initial proto and decided it needed more refinement - details which I will cover when the documentation is released. However, things came to a grinding halt when TraxMaker (part of the CircuitMaker CAD suite) stopped working in early 2024. I made the decision to switch to KiCAD (a good move!) and had to redesign the board from scratch. After another 2 proto/dev cycles, the amplifier module PCBs are finally where I want them to be, and quick bench testing shows peak mains hum harmonic components at below -125 dBr reference 60W RMS into 8 Ohms (the power limit of my test lash-up) and <35ppm distortion.
I am currently finalising the PSU +inrush PCB and that will go off for manufacture sometime next week. In parallel with this, the mechanical layout is also being finalised.
Part of the delay in this project has also been the fact that I became a grandfather (yeah, I'm old) for the second time and that entailed putting a lot of stuff on the backburner, and the decision to move closer to family, which we will do in the next 3 weeks. Its chaos here with boxes all over the place, packing etc.
For all of the above reasons, the nx2 won't be completed and released for at least another 2 months, but hopefully you wiol get an idea of whats n the pipeline from this intro. The boards will be available on the hifisonix web shop if you want to build one (but only after I release the completed amp + documentation).
Here are the specs (note these may change once the completed, housed amplifier is re-measured)
I've attached some photos below - taken in my workshop today in amongst the packing boxes. (note the front plate is still being assembled so looks a bit manky - it still has to be cleaned, screws fitted and then polished)
I started work on this in September 2023, assembled the initial proto and decided it needed more refinement - details which I will cover when the documentation is released. However, things came to a grinding halt when TraxMaker (part of the CircuitMaker CAD suite) stopped working in early 2024. I made the decision to switch to KiCAD (a good move!) and had to redesign the board from scratch. After another 2 proto/dev cycles, the amplifier module PCBs are finally where I want them to be, and quick bench testing shows peak mains hum harmonic components at below -125 dBr reference 60W RMS into 8 Ohms (the power limit of my test lash-up) and <35ppm distortion.
I am currently finalising the PSU +inrush PCB and that will go off for manufacture sometime next week. In parallel with this, the mechanical layout is also being finalised.
Part of the delay in this project has also been the fact that I became a grandfather (yeah, I'm old) for the second time and that entailed putting a lot of stuff on the backburner, and the decision to move closer to family, which we will do in the next 3 weeks. Its chaos here with boxes all over the place, packing etc.
For all of the above reasons, the nx2 won't be completed and released for at least another 2 months, but hopefully you wiol get an idea of whats n the pipeline from this intro. The boards will be available on the hifisonix web shop if you want to build one (but only after I release the completed amp + documentation).
Here are the specs (note these may change once the completed, housed amplifier is re-measured)
I've attached some photos below - taken in my workshop today in amongst the packing boxes. (note the front plate is still being assembled so looks a bit manky - it still has to be cleaned, screws fitted and then polished)
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Congratulations on the birth of your second Grandson and on the birth of a new amplifier!
Congratulations Andrew!
The grandson is your first priority for sure! Spend time with him. Your new invention can wait a little more 🙂
BTW nice job,I like the smd choice 👍
The grandson is your first priority for sure! Spend time with him. Your new invention can wait a little more 🙂
BTW nice job,I like the smd choice 👍
Andrew's schematics are always published.
I think we just have to wait for his final corrections😉
I think we just have to wait for his final corrections😉
NX is a very good amplifier. I built it in 2015. NX2 it will be better 🙂
The nx2 is a CFA - the loop gains are generally lower than blameless type VFAs.
A worst case load I usually cater for is an electrostatic which usually lie between 1uF and 3uF worst case load. I agree most conventional speakers are nowhere near this.