Building a Pearl 2

One note when purchasing parts -- get a good number of the P-Channel MOSFET as they can be "twitchy" -- very static sensitive. For a one-off project I would order 10 -- they are $0.72 per unit, but if you buy 10, @$0.635.

Somewhere in this very long thread there is a recommended replacement.

FWIW, have not managed to damage the surface mount version (ZP3310F)
 
I went back to my Mouser project from several years ago. It looks like the 3300uF is 7.5mm and the 10,000uF is 12.5mm.

It looks like the 10,000uF is 10mm unless I am reading this wrong. I have the PN from 6L6's spreadsheet.
 

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What is the point of R19 at 47K5 when there is also R20?

I would omit R19 and just use R20 to set the loading impedance to match your cartridge.

For example if you soldered in R19 at 47K5 and then want an input impedance of 47K to load your MM cartridge you'd have to set R20 at a super high M ohm value to get the equivalent resistance down to 47K.

Why not just use one resistor to start?
 
I put 47K5 in R19 by default for MM carts, and then a few resistors on a switch wired to R20 for switchable input impedance to 100 or 470 for MC carts.
By default, no resistor was switched into R20 so it would be 47.5K.

If you will only use MM (or MC), you can put that specific one in either R19 or R20.
 
Another Pearl 2 comes to life

The Pearl 2 sounds great, but I do hear a buzz when going over half volume (B1K > M2X Cedarburg). The buzz follows the right phono input coming from my SL1200 upgraded with Jelco 750D and the Jelco JAC-502 cable. I switched from Shure V15III to Nagaoka MP200 on different headshells (swapped polarity on both) and problem is the same. There was no buzz with previous phono pre (Bottlehead Reduction) or Sansui 8080. Like I said, it sounds great with no hum or hiss, just that buzz when going up in volume. Any ideas?
 
Here's an update to my previous post. I swapped in my Thorens TD150 with a Denon DL110 and it is silent until max volume with no buzz at all! Then I noticed it didn't swap leads at the cartridge. So I went back to the other TT and swapped the polarity back and no buzz. Seems trying to correct for phase at the cart is causing buzz in my case. Now I have correct polarity at cartridge and speaker, just letting the Pearl 2 and B1K do their thing and it sounds awesome. Tuner and DAC will just have to suffice with reverse phase as phono is my primary critical listening.
 
Yes the store board is a bit big. I made a custom board thats much smaller and fits directly in a Hammond 1455 chassis. I have a few left.
PCB for bi-polar caps/bridge rectifier (for Pass Pearl 2)


itsikhefez,

Are your boards based off of Carlos Filipe's LM3886 snubberized kit boards?

If so; do you have any to sell or by chance know if the ones in the DIY store are based on the ones I mentioned above?

Thanks, James