So, I have maxed out on building LM3886 chip amps and want to level up to Papa Nelson Pass Class A's.
What is the recommendation and ethical way forward for PCB sourcing ?
In particular, I plan to build an F5 as it seems to be loved by all, and is probably just what I want, a classic 25w class A.
The challenge is getting a PCB...
The diyaudio store has been out of stock for ages, ebay is full of "inspired by" PCB's that seem to claim some relationship to the original Pass design.
So what to do?
Are the diyaudio boards likely to return to stock, are they authentiic to the Pass design.
If the philosophy is "open source" are the gerber files published?
What is the recommendation and ethical way forward for PCB sourcing ?
In particular, I plan to build an F5 as it seems to be loved by all, and is probably just what I want, a classic 25w class A.
The challenge is getting a PCB...
The diyaudio store has been out of stock for ages, ebay is full of "inspired by" PCB's that seem to claim some relationship to the original Pass design.
So what to do?
Are the diyaudio boards likely to return to stock, are they authentiic to the Pass design.
If the philosophy is "open source" are the gerber files published?
For something that is out of stock at the Store, you might want to try placing a "Wanted to Buy" post in the swap meet section of this forum. There are unused ones sitting around in basements and closets, and you can probably pry one loose fairly easily.
This might be the perfect stimulus, which helps you finally make the decision to lay out printed circuit boards yourself. The circuit is public domain and it has been proven to work by many dozens of previous builders. Photographs of other layouts are easy to find, so you can get a very good starting point for your own parts-placement positions on your board. The Universal Mounting Specification is public domain (link) so you can create your PCBoard to be fully compatible with pre-drilled heatsinks from the diyAudio Store.
You don't need a degree in engineering to lay out PCBs; many of the best PCBs here on this site were laid out by people with zero university training.
You don't need expensive software; some PCB packages are completely free and others are quite low cost.
All you need is a can-do attitude and a willingness to learn.
You don't need a degree in engineering to lay out PCBs; many of the best PCBs here on this site were laid out by people with zero university training.
You don't need expensive software; some PCB packages are completely free and others are quite low cost.
All you need is a can-do attitude and a willingness to learn.
Thanks one and all - I have ordered a clone board from China (jims audio) , semiconductors from the diy shop, and started looking down the back of the sofa for resistors of the correct type, and deciding on chassis / heat sink combinations. It is tempting to splash out on the universal 5U, so that its the last heatsink I ever buy.
I really want to make an F5, but may be i will try an M2 or F6.
And yes; I should learn to spin up my own gerber files, since I am rather impressed with the open source LM3886 board that member 00940 championed
I really want to make an F5, but may be i will try an M2 or F6.
And yes; I should learn to spin up my own gerber files, since I am rather impressed with the open source LM3886 board that member 00940 championed
A word of caution regarding those clone boards from China:
I discovered a problem with a pair of "Penultimate Zen" boards from the same vendor. The pinout for the bipolar transistor used as part of the Zen current source did not match the schematics, or the standard ZTX part normally used. You are advised to carefully check the routing of the boards you receive.
I discovered a problem with a pair of "Penultimate Zen" boards from the same vendor. The pinout for the bipolar transistor used as part of the Zen current source did not match the schematics, or the standard ZTX part normally used. You are advised to carefully check the routing of the boards you receive.
Thanks for the warning; I will check and test the PCB's end to end, in particular Q5 ZTX550 and Q6 ZTX450 pin out, and report my findings.
I am hoping my finished F5 passes the smoke test first time round...