Thank you gentleman, I was looking for the specific part listed on the sheet, should have searched for wattage and value instead, thanks.
I’m about to go out of town but if you can’t find the 0R75 or 0R33 in a week, drop me a DM
From my understanding, I should be able to run a stock B1 off the mini's BOM PSU as well (making an integrated). Is this correct or am I missing something?
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What would be the benefit of a B1 in this case (integrated amp)? I am not sure what the gain of the ACA mini is (searching for it). Maybe you need some gain in front? Or maybe not.
What about ACA and H2? Would that sound good? H2 has gain and both invert so net effect is no inversion + more gain. Outputs of ACA are labeled inverted on the schematic to make up for the inversion.
The benefit is I have a B1 that's unused lol. This is for a desktop setup where I just need a volume control and not a lot of volume. Maybe the lack of gain will be problematic and maybe it won't. Will find out...
FWIW I use an ACA Mini as a desktop amp with a connect direct to the DAC ouput and I use the level control on the PC. It works very well. I expect you will have no problems w/o a pre.
In post 241 Rayma says ACA Mini gain is about 15db. The gain plot in the original ACA documentation shows it is a bit lower at just over 14 dB.So both are a bit lower than typical power amps but also so simial it would be hard to tell the gain difference between them from listening.
Thanks both of you
So roughly voltage gain of 5, means with the usual 2V sources more than enough gain to drive LS up to the amp's power limit, unless you run excessively high impedance LS, at which point you are probably better off looking into another amp.
Bottom line : from a pure gain chain POV, no preamp with gain is likely to be needed, and a simple passive pot between source and ACA mini does the trick. Unless I am mistaken of course, just to answer the initial question a few posts above
Claude
So roughly voltage gain of 5, means with the usual 2V sources more than enough gain to drive LS up to the amp's power limit, unless you run excessively high impedance LS, at which point you are probably better off looking into another amp.
Bottom line : from a pure gain chain POV, no preamp with gain is likely to be needed, and a simple passive pot between source and ACA mini does the trick. Unless I am mistaken of course, just to answer the initial question a few posts above
Claude
I'm allergic to digital volume 🙂
While I can just use a passive pot, again, I have a B1 just sitting here so why not do something with it?
The power switch does not disconnect the power, it simply shuts off the bias current.
May I ask the reason for this (I am not EE gifted)? What is the benefit over just switching the DC coming from the PSU?
I got my ACA mini up and running tonight, and what a good little amp it is! Building and tuning has been a breeze and now it is playing in my study since an hour ago.
I received the board by Mark Johnson's design and the kind effort of KevinHeem. Not to mention that Papa contributed the Mosfet's (and original design..). Thank you! This is a good time to do DiyAudio.
In a short while it will be used in my main system when I upgrade my F6 with new Mosfets and SMPS. I expect it do very well there.
I received the board by Mark Johnson's design and the kind effort of KevinHeem. Not to mention that Papa contributed the Mosfet's (and original design..). Thank you! This is a good time to do DiyAudio.
In a short while it will be used in my main system when I upgrade my F6 with new Mosfets and SMPS. I expect it do very well there.
In my limited technical understanding you would need a B1 to run long(ish) cables from pre to amp. Since you only need an integrated volume control, a pot alone should work for you.
With 15dB I am quite confident you do not need more gain. Just in case (as others suggested) the ACP+ has more than enough. And if not gain, it can also add a little of its own personality (that I really love).