My version of the Mini is up & running and playing music 🙂 Big thanks Mr. Pass & everyone involved in making this fun and cool project available to all of us!
I always like to customize so I made my own pcb that can be fixed to a single bigger heatsink. Plan is to put it in a square(ish) case to protect it from the small kids and cats that are never far away...
If anybody wants the kicad files and/or gerbers, let me know, happy to share them
I always like to customize so I made my own pcb that can be fixed to a single bigger heatsink. Plan is to put it in a square(ish) case to protect it from the small kids and cats that are never far away...
If anybody wants the kicad files and/or gerbers, let me know, happy to share them
Attachments
I am also building an ACA mini with quite big heatsinks. The enclosure is a Mini Dissipante.
With V0 11,5 and VB 0,3 VDC the heatsinks dont get hot. What would be the upper limit for VB without destroying the FET's?
With V0 11,5 and VB 0,3 VDC the heatsinks dont get hot. What would be the upper limit for VB without destroying the FET's?
In this build I inserted a 100k potentiometer as it was available on my private stock
In another version, built before, I have a 25k
That, and also: what changes when running a lower or higher Vb? Output power?
just be specific - what is you exactly want
or you'll get universal answer - even Wooden Stove is possible
or you'll get universal answer - even Wooden Stove is possible
What a nice little toy - never ever I have built an amp so quickly 🙂 Not yet integrated into a frame, but already usable 😉
The board is by @jimk04, parts are from the official Completion Kit, the "a little bit too expensive" matched JFETs from the store, and Vishay MOSFETs.
The assembly and adjustment is incredibly easy - also thanks to the great (as always) guide by @6L6.
Big thank you to Papa!
The board is by @jimk04, parts are from the official Completion Kit, the "a little bit too expensive" matched JFETs from the store, and Vishay MOSFETs.
The assembly and adjustment is incredibly easy - also thanks to the great (as always) guide by @6L6.
Big thank you to Papa!
I'm just curious as to why you would bias lower or higher. What characteristics of the amp change in what way when Vb changes. In the manual, Nelson writes "...you can venture into the 0.35 V territory."
So why would I do that?
So why would I do that?
THD level and THD Spectra should change, but how and for how much, that's for Papa to explain
just take in account that BAF is day after tomorrow, so he's certainly busy
just take in account that BAF is day after tomorrow, so he's certainly busy
The bias stabilizes pretty quickly due to the small sinks, being a short time constant. 20 minutes or so.
You can bias it pretty high if you want, as long as you can put your hand on the sinks...
You can bias it pretty high if you want, as long as you can put your hand on the sinks...
OK, thanks Nelson!
Now I understand better why you use such small heatsinks. Not just to keep costs low!
My intention was to build an ACA mini with a very long life expectation: big heatsinks and 35V filter caps.
I will check the time constant of stabilizing bias and report here later.
more bias sbabilized faster ....nice to know in ACA box !maybe can take few volt more