As additional info for the power supply going into hiccup mode, check post 968 and 969 of this thread.
https://www.diyaudio.com/community/threads/diy-aca-mini.379037/page-49
https://www.diyaudio.com/community/threads/diy-aca-mini.379037/page-49
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Thank you, NP and e_fortier. I had seen the posts about the power supply but hadn’t experienced what it looks like. There’s always more to learn- thank you!
I made a small change to the version shipping this week to slow the startup of the bias of the amplifier which helps with the switcher protection. Keep in mind though that it's still possible to put the supply into protection by driving both channels full power into 4 Ohms. If that happens then you switch it off, wait a little bit and turn it back on.
Of course you can always get a heavier duty supply - one reviewer did just that.
Of course you can always get a heavier duty supply - one reviewer did just that.
Congrats! What's going on in the neighborhood of R1 and C1?new baby born Thanks Nelson for di cute amp
Nice work.new baby born Thanks Nelson for di cute amp
I keep wondering about the rubber band around some of your heatsinks ? We see this on tubes to reduce microphonic...but on heatsink...I’m puzzled 😕 😜
Now that I know what to turn on first I'm having no issue with my first mini. ;-) And I completed my second one and that one looks good too.
Dumb question: what is the input impedance of the ACA Mini? Playing with a passive preamp (clone of the Magnequest ingot) so it will help to know. My guess is about 110k Ohms (the two 221K resistors in parallel)? But I know I have a lot to learn, especially about SS amp schematics, so I'm asking.
Thanks in advance, and for such a great and supportive forum. (I never expected my last question to be answered by NP himself!)
Pete
Dumb question: what is the input impedance of the ACA Mini? Playing with a passive preamp (clone of the Magnequest ingot) so it will help to know. My guess is about 110k Ohms (the two 221K resistors in parallel)? But I know I have a lot to learn, especially about SS amp schematics, so I'm asking.
Thanks in advance, and for such a great and supportive forum. (I never expected my last question to be answered by NP himself!)
Pete
Increased R4 to 22k, slowing down the bias turn-on. This way you should be able to apply initial power with the switch in "on" position.
I just found out that one of those extremely rare, super limited edition, red Almost Clone boards with the gigantic EXPERIMENTAL label, has been held back in its original pristine state. No fingerprints, no components, no solder, no contamination of any kind. Until now.
It seems that one of diyAudio's premier teachers, evangelists, and mentors has decided to gift his own red board, plus a full set of components (!!) to a beginner/intermediate DIYer, as a first project. Wow! I hope and trust the build goes smoothly, and I'm confident the recipient/builder will be delighted -- gobsmacked -- by the results.
What a great community.
It seems that one of diyAudio's premier teachers, evangelists, and mentors has decided to gift his own red board, plus a full set of components (!!) to a beginner/intermediate DIYer, as a first project. Wow! I hope and trust the build goes smoothly, and I'm confident the recipient/builder will be delighted -- gobsmacked -- by the results.
What a great community.
Did not reach the store up to now, Jason?Packing up the Essentials kits today, and tomorrow they go off to the store.
Recommended resistors for R8 R9 (0R75 3w Draloric) are out of stock in Mouser Spain. Some other recomendation?
I'm thinking of:
Draloric AC 0R68 3w
Draloric AC 0R75 5w
paralelled 1R5 2w metal film
Thanks in advance
Victor
I'm thinking of:
Draloric AC 0R68 3w
Draloric AC 0R75 5w
paralelled 1R5 2w metal film
Thanks in advance
Victor
Those will work very well. You may have to install the resistors standing vertically or perhaps at an angle due to the resistors being larger than the pads, but it won’t effect the operation at all.