NiWatt Main Circuit Boards
"I would have written you a shorter letter, but I didn't have the time".
Variations of this phrase have been attributed to Mark Twain and a host of other individuals.
We embrace Occam's Razor principles in our designs, and as much as we eliminated all what was unnecessary, the project felt unfinished. Something about the layout was just a bit "off".
We let the NiWatt project sit.
This past week, we turned our attention to pre-production prototyping.
What does that mean?
You've designed, developed, made change upon change, revisited your assumptions countless times.
You've auditioned over and over again, and you might think you're ready to go into production.
But you're not ...
The final step remains: revisit the product with a focus on simplicity in manufacture and ease of maintenance.
Power Supply Board - Input & Driver
Power Supply Board: Output Stage
The circuit has proven itself on a sonic basis.
We configured the design so there's barely any wire in the signal path. It seemed simple (and direct) enough.
Viewing this through the eyes of either an assembly technician or repair person however, there were improvements to be made.
Sometimes, the fastest progress you can make is to set the project aside and let it percolate in the background.
Be Your Own Worst Critic
When you "park" a project, returning to it requires some time for re-familiarization.
This brings the fresh perspective you need.
We found that by segmenting the key circuit elements into their own circuit boards, we not only simplified manufacturing (reduce the possibility of errors), and made the service technician's easier, but we improved the ground path. Not bad for a week's work.
300B Cathode Circuit Board
Like a Duck - Calm on Top and Paddling like He!! Under the Surface
The work product you see on this page appears simple enough (Occam's Razor again), and yet it represents a full week of shifting components around, and around ... and around again.
Working on a CAD tool helps, but you need to play in real, physical space, because images on a screen don't convey all of the details - especially how a human being will interact with it.
An Eye Toward the Future
Every amplifier (whether tube or solid state) requires servicing after approximately 15 years, to inspect and premptively replace any electrolytic capacitors (typically in power supplies in both types, and frequently in the cathode circuit of some tube sections).
Electrolytics you say?
Don't frown - we've been through every variety of capacitor, and the electrolytics we selected compare with the very best, whether they be unobtanium Black Gates, Cerafines, Oilers, and everything else we tried.
The capacitors we selected have industry leading life spans.
Capacitors: Radial vs. Axial
If you build amplifiers, you have likely witnessed the the steady disappearance of axial capacitors. What remains are a few models from a a limited number of manufacturers, and one of them (F&T) was recently sold.
Knowing this trend will not reverse, we designed the boards to accommodate radial style capacitors. The choices are far more broad, and that technician you approach for that "recap" in 15 years won't suffer frustration - trying to fit a radial cap onto board designed for axials.
Small things matter ...
