advertisement


Naim style power amps DIY

P

Puggie

pfm Member
I'm going to blame this place for my interest in Naim power stuff in general, I've never really paid it much attention. That and a mate of mine going for a job interview there made me give it a look.

So, I fancy having a dabble with something Naimesque in a power amp, and want to do it on the relative cheap to compare with my A&R A60. This is only going in my desktop setup for work, so I do not need ear bleeding levels of power. Having a look at Neil McBride's web site there is a NAP135 style amp, board designs are single sided and artwork is on his pages, so I could just print off and go swimming in the ferric.

I've read more than once that the Naim amps are basically all the same design and just scale the number of outputs and power rails/regulation. So I have a pair of 120VA 18-0-18v toroids in my stack of stuff, if I was to power a NAP135 board from 2x25v(ish) would I basically have something resembling a Nait power wise?

Thoughts?
 
The regulator circuit on McBride's site isn't quite correct so best avoid it. The Chinese clone boards on ebay copy it so again best avoided.

The circuit for the amp board is correct but the feedback cap us not the correct value. Circuit shows 68uF but naim use 100uf for the 135's and 250's and 50uF for the other amps.

These boards are more or less correct (just a couple of caps indicated in reverse polarity compared with originals and not critically so) and are well constructed. Just leave out the SoA components if you don't want them. They also give you the option of using flat pack output devices

https://www.ebay.co.uk/itm/32156507...d=link&campid=5338728743&toolid=20001&mkevt=1
 
This site contains affiliate links for which pink fish media may be compensated.
Thanks for the input, I was just planning on etching a pair of boards from McBride's artwork, plain old FR4.

Is there a decent/accurate regulator design documented in the public domain?

Could I just run them unregulated for starters, just regulate the AC and bung some chunky caps across the rails?
 
It’s only the front end that needs regulating.

Have a look at the hackernap.

Pete
 
Many thanks for the link Alan. Without trying to sound ungrateful is there any advance on V1.3 for the Gerbers/board design?

its one NAP and two CAPs per channel?
 
Thanks @Mynamemynaim
Please see more of photo
https://flic.kr/p/2mCkice
https://flic.kr/p/2mCA5ip
https://flic.kr/p/2mCuHWr
https://flic.kr/p/2mCA5mL
https://flic.kr/p/2mCAdRr

I build this of think about shoes box (Nait1) but install amp board from nap200 design and hand make preamp of nac42 without buffer and make MCU control unit base of Atmel Attyny MCU (selector of inputs)
https://flic.kr/p/2mCuSAa
https://flic.kr/p/2mCDADA
https://flic.kr/p/2mCDAEh
https://flic.kr/p/2mCAiTp
https://flic.kr/p/2mCK5ER
 
Last edited:
Brilliant to see someone etching their own circuit boards ...
I used to do it (seems so long ago now) but it's so much fun I might start again!!
 
Dear @Mynamemynaim
Absolutely right!!!
Best way and low time for diy boards at home :)
Because when you order board in Chinese manufacturing you wait about four weeks
Please look for phonostage with preamp
https://flic.kr/p/2mCEXh7
this board diy at home too :)
Based on NA322 phono board and litle my design for preamp circuit from NAC42. I want build phonostage to 1v output signal from 2-5mV MM head
 
You must log in or register to reply here.


advertisement


Back
Top