Pearl 3 Burning Amp 2023

Well, the audio gods spoke to me Sunday. I was on a bus, headed to the airport wishing I had got the Pearl 3 playing music and I get a text just 15 minutes into the trip..."We are sorry, your flight has been canceled. Please call..."

So 30 minutes later we have a new flight Thursday and the bus driver drops us off at a pub and restaurant with with all our bags and a kids car seat. We stuck out like a sore thumb, and I was already fully aware this was all because I didn't finish the Pearl 3. I had unfinished business and the audio gods spoke up.

So, after building a couple ACA Mini's yesterday afternoon with my brother (wow, those things sound amazing!!), I spent today finishing the Pearl 3. I'm so close. One question....

I have been changing R27 to get under 5ma. I now have two 560 ohm resistors, but the two boards are pretty different. One board shows 4.44mA, while the other is still just out of spec at 5.11mA. I presume it's OK to have different values for R27 between the boards in order to get in spec, and perhaps have closer matching current?

Thanks in advance for any help. I'm so close! Toys4Boys and I have been neck and neck all day with our builds. It's been fun sharing our progress and lessons learned.
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it's OK to have different values for R27 between the boards in order to get in spec, and perhaps have closer matching current?

yes

resistor value is irrelevant per se, goal is to have prescribed current

same as you are going to shower - who cares how much left or right faucet is set, as long water temp is as you want it
 
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Thank you Zen Mod! I figured that was the case, but my noobness made me feel like I needed a hand on my shoulder, a confirming nod, and a great analogy :rofl:

I shall pursue matching currents and let R27 be what it may for each board.

:cheers:

[EDIT: 680 ohm on right board gives 4.3mA and a 560 ohm on left board gives me 4.4mA. I suspect that's plenty close. Thank you again ZM! Water temp is perfect for me.]
 
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Well, the audio gods spoke to me Sunday. I was on a bus, headed to the airport wishing I had got the Pearl 3 playing music and I get a text just 15 minutes into the trip..."We are sorry, your flight has been canceled. Please call..."

So 30 minutes later we have a new flight Thursday and the bus driver drops us off at a pub and restaurant with with all our bags and a kids car seat. We stuck out like a sore thumb, and I was already fully aware this was all because I didn't finish the Pearl 3. I had unfinished business and the audio gods spoke up.

So, after building a couple ACA Mini's yesterday afternoon with my brother (wow, those things sound amazing!!), I spent today finishing the Pearl 3. I'm so close. One question....

I have been changing R27 to get under 5ma. I now have two 560 ohm resistors, but the two boards are pretty different. One board shows 4.44mA, while the other is still just out of spec at 5.11mA. I presume it's OK to have different values for R27 between the boards in order to get in spec, and perhaps have closer matching current?

Thanks in advance for any help. I'm so close! Toys4Boys and I have been neck and neck all day with our builds. It's been fun sharing our progress and lessons learned.
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Nice build, but one question..........
Why the massive power wires inside the Pearl??
The total comsumption is approx. 100mA pr. board, so my thoughts were, that you maybe could
have done a prettier job with thinner wires ;)
Just my 5 cents.
 
Well, all I had on hand is 16ga, so it was a matter of availability (I am building this at my parents house, 1500 miles from my home, and neither one knows how to solder). I suspect it'll work fine though. I think it's still pretty, even with the "cankles".

However, all that really matters in my book is what is sounds like 😀
 
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Spend $200 on a name brand (not anonymous amazon dreck) 4.5 digit DVM and measure the resistance of three or four dozen.

Connect a supposedly "220 ohm 0.5 watt" resistor to your lab bench power supply and slowly dial up the supply voltage until your 4.5 digit DVM reads 10.50 volts. Now the power dissipation is (10.5 * 10.5) / 220 = 0.501 watts. Let it roast in that condition for 15 minutes. Was the resistor able to actually dissipate 0.5 watts without destroying itself?
 
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First up
a recording that I've heard at least 100 times on so many systems. I imagine she'll break in, but from the get-go, lovely! Warm but detailed, excellent harmonic structure, solid soundstage/image! All is not perfect yet, I have some strange buzz/hum from the location of the PS, but tolerable for now, more of a project than I'm up for at the moment.

Kudos and thanks to all who have made this and the other wonderful offerings so accessible!
 
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The version in question is from Acoustic Live, '97, and is almost definitely the 1 played at shows, great recording, better guitar player. According to the totally reliable internet, this song was written for Keith Richards, Keith don't kill yourself. Originally released in the 70's, Keith will outlive us all!