I like your "a little heat does not scare us"
Here is Nelson pass commercial amp being reviewed. Hope this link shows up. I will only say $5.00 and then you have to find it in the article. Pretty funny. A great read and I think does pertain to the logic behind his design philosophy and the aca amps.
Pass Laboratories XA200.8 monoblock power amplifier | Stereophile.com
Email that my aca boards are in the mail......... Yahooooo.
Here is Nelson pass commercial amp being reviewed. Hope this link shows up. I will only say $5.00 and then you have to find it in the article. Pretty funny. A great read and I think does pertain to the logic behind his design philosophy and the aca amps.
Pass Laboratories XA200.8 monoblock power amplifier | Stereophile.com
Email that my aca boards are in the mail......... Yahooooo.
This has been discussed previously...some mentioned a method applied in another First Watt amp circuit to prevent the noise, but I read nothing that suggested it would damage anything by leaving it as is...I tested with both 19 and 24 supplies and got the same results.
I vaguely think I remember someone explained it had to do with capacitors charging in the circuit.
My theory before I read that was that I had dirty power in my lines that was giving the ACAs indigestion. Once they “gassed off” so to speak I believe the sound was definitely free of any constipation...definitely a lot more clarity to my ears than my other amps that don’t fart on start up. 😂
I have no noise at all when I power up the ACAs and I have large output capacitors (6600 uF). My only explanation is the PSU which is a LCLC with large chokes. My theory is that the current builds up so slowly so the output transient is so low in frequency that the woofer "eats" it all without any audible noise.
Well-stated. I for one am waiting in greedy anticipation for the goodies to arrive. If this build works out like I believe it will, then I'm in for a real treat - "burps", "farts" and other pootilagenous noises be d**ned.
Yes, I made that word up...
The speaker AC coupling capacitor (3,300uF) charging current is part of a "total" current that runs from the power supply rail, via both MOSFETs. The "part" of that current will go "towards" the coupling capacitor; the amount of that current depends on how large the capacitor is, its ESR, and the speaker impedance... you can try bigger capacitor, the fart should be longer, but less prominent
. You can also observe the "fart" by looking at the bass driver membrane movement - to see if there's any danger to bass drivers... Other Mr. Pass designs limit the initial current by slowly "opening" the MOSFETs, so the total current build-up is gradual.ACA Parts kit is here!
USPS just dropped off my ACA Parts Kit Unfortunately, I have to work the next three days, but have Tuesday and Wednesday off.
Can't wait to build this and settle in for some listening...
Everybody, please post pics once your's is built. I'm sure we'd all like to see the builds!
I talked to Jim (6L6) and he is frantically working on a new build guide. THANKS Jim for all your hard work!!!
USPS just dropped off my ACA Parts Kit
Unfortunately, I have to work the next three days, but have Tuesday and Wednesday off.Can't wait to build this and settle in for some listening...
Everybody, please post pics once your's is built. I'm sure we'd all like to see the builds!
I talked to Jim (6L6) and he is frantically working on a new build guide. THANKS Jim for all your hard work!!!
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I got the kit and am having fun so far.
In case there are any other noobs out there like me, it was confusing trying to figure out all the resistor values because they aren't marked, which is probably completely normal.
I used this to figure out the values and match them up to the schematic -
Digi-Key 5 Band Resistor Value Calculator
One channel down and three more to go.
In case there are any other noobs out there like me, it was confusing trying to figure out all the resistor values because they aren't marked, which is probably completely normal.
I used this to figure out the values and match them up to the schematic -
Digi-Key 5 Band Resistor Value Calculator
One channel down and three more to go.
Attachments
You should have gotten a single page piece of paper in the kit box that has the values/colors listed. See pics.
Attachments
