Last, but (hopefully) best ever modified and complete NAD 3020

[poundy]

all in now.It needs a clean up, but what a shame about the 3rd transistor down, the print came off and broke so i had to do a repair.
I have to decide now if to take it of and connect with wire or leave it.
It just looks scruffy like this
would you leave it or take it off and connect it up more neatly with wire?

so much better access around the amp now

before and after photos, and the set up now complete.Ive not removed or modified for driver removal yet, ill try the amp first with them in to make sure it all works first.

 

[Mooly]

It needs a clean up, but what a shame about the 3rd transistor down, the print came off and broke so i had to do a repair.

I'd leave it. You never see it and another way to think of it is that it id no worse than many a thing NAD would do in production. Its fine

 

[poundy]

so im getting close to do some of the final bits now
ive replaced the old composite resitors with film types
ive also altered the regulated supply transitors so they are not near the caps(as @Vrystaat stated the caps dry out) all of these ar also uprated to 50v so they should last longer
as you can see in the 2 comparative photos

 

[wg_ski]

Thought about putting one of these little heat sinks on those pass transistors? Makes a hell of a difference in operating temperature when you’re dissipating a watt or two.

 

[poundy]

I did look at doing that but it kind of defeated the object in this case as it brought the heat back closer again

 

[Mooly]

Modern 105C rated caps will be in a different league to the NAD standard fitment so there should not really be any reliability issues cap wise.

 

[poundy]

finished converting the back now, so its all down to a few little bits really,put the power cord back in and the switch,alter the base feed to the multiplier for now
I will try it with the drivers first to make sure it works.

Actualy the design, i think is actualy quite good from a lay out perspective,now the cables have been removed you can see its almost mirror image more or less for each channel on both pre and power sections,this proberbly accounts for the spagetti junction print layout.
Hopefully by the time ive finished, i will at least given it justice with the work that has been done.

 

[Mooly]

Have to say that is looking really good, certainly a one off

 

[poundy]

Thanks I'm pretty pleased with it. Once I've finished it I'm going to try and find that buzz on one channel of the one we did with the soft clip switch and the op amp, I could never find what caused it