Building a Pearl 2

6L6

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An XLR will work. The reluctance most people have is that there's the possibility of plugging your power into the input of another device... which would be detrimental everything.

If you are absolutely dying to use what's on hand, go ahead, that is a reasonable reason.
 
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Wrap a piece of tape around the cable at each end, right next to the XLRs. Use a wide black marking pen to write "DEATH CABLE!!" on this tape. Remind future-you (possibly inebriated-future-you) that this is not an ordinary cable.


Amazon.com: Glow X Fluorescent neon Gaffer Tape - 5 Pack. Cloth matt Finish is Reactive Under UV Blacklight. for Glow Parties and Art Projects. Each roll is 18 feet by .5 inches

Good Idea! How about skull and crossbones? :)

One more thing, I was double checking everything before my order and I realized I skipped over part C15 because I'm not sure what kind of capacitor that is?

Thanks
 

6L6

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Well, the circuit needs 24v regulators, so why not use a fixed.

Adjustability gains you nothing in this case, and anyway, your issue is input voltage, not output voltage.

Most importantly, the 317/337 have a different pinout and therefore don't fit the PCB, AND the required parts for set resistors and such are not on the PCB.

Wayne has used those very same regulators in products that cost well north of $10thousand, so I'd be perfectly content with them. :D :D :D
 
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An 18V transformer is probably too low. The voltage after the DC supply under load but before the regulator may be around 24V or so, leaving not enough headroom for the 24V regulator to do its thing. See post #1 - the recommended minimum is 22V (shown in power supply schematic).
 
Yep, may be the best way, if I return the one sent me & get them to send an 18 V trans. Then I would get between 25 & 29 VDC, just depending on how many volts the trans is when it arrives back. Thanks for your help.
Cheers


Just build it stock according to the schematic - I built one recently and it's pretty simple to do. The regulated supply will also work as 6L6 said but it's overkill.
 
We Guy's finally got there, and thanks McQuaide it sounds fantastic. I had been using a A/K AD797 up until this one. The Pearl is certainly superior in the base region, much more impact full, which I like as I am a base freek. To early to tell about the remaining frequency spectrum. Certainly my Temaad Merlin Titanium arm & Goldring Eroica L are making some glorious sound.

Cheers & thanks for all your help everybody.:D:D:D

:):c_flag::cheers:
 
Well OK than, after only about 8 years or so it is time to get my Pearl 2 up and running.

Years ago I had the boards pretty much stuffed with the necessary components.

My plan is to house the Pearl 2 and B1 preamp (which has already been built and used) in the same enclosure with a Bill Thompson PCB to control motor speed.

So I am just looking for any changes/addition to the parts for either the Pearl boards or the Chipamp power supply.

From what I have read so far is:
C15 - Leave out ( I put a jumper in by mistake)
R15 - Jumper
C22 - Leave Out, no jumper
R20 - Leave out, no jumper
C7 - Can cause issues. Wayne after the Pearl 2 article was published recommends leaving out.

-Also the snubbers in the first post. It appears they are .22 something as I could not make out if they are micro, pico etc. I also have to really read a bit more to figure out where they are going.

-I also noticed on a picture that RussellC posted that a jumper wire was placed on the Chipamp board so I am assuming that will be needed.

- So with the Chipamp I purchased years ago which is the same as I think a lot of folks are using, the LM3886 power supply, but my question is, are the little boards that came with used at all?

My plan with this is to be able to run my TT through this and also a CD player. So with that config I believe the TT will come through the B1 - Pearl and the CD just through the B1 and out.

So are there any other components for the Pearl or Chipamp boards that I need and what is the value of the snubbers?
 
Wow, it has been so long ago that I built the B1 I forgot I put Clarity ESA caps in here.
 

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6L6

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Snubber is 0.22uF. You could also put about 5 ohm in series with that cap, that will help snub better.

Russel used the chimp board to great effect, if I recall, so configure like his. (Can you say what post # the photo was in?)

What chipamp "little boards" are you referring to?