Building a Pearl 2

Thanks for your answer.

@folkdeath95 -- the 3.3nF capacitor should be of the "X" type -- if you can't find this type use a 1kV ceramic disc.
On my Aleph J, I use a Murata Ceramic Disc. I don't remember where I was told to choose it. Is to ok (it's only 250 Vac)?

the MUR820 shouldn't need heat sinks they will only dissipate a fraction of a Watt.
OK.

220nF for the transformer snubber seems a bit much -- see Mark Johnson's thread on the "Quasi-modo jig"
I just copied the value on 6L6's schematic (given by Wayne, I think). I'll have a look at this thread.

Ground loop breaker -- I use them here, but our mains scheme is different from the EU.
Do you mean that it is useless in EU or that the ground loop breaker should be wired differently?
 
I just copied the value on 6L6's schematic (given by Wayne, I think). I'll have a look at this thread.

the value of the snubber cap is a function of the leakage inductance of the transformer. to me it seems a bigger issue with EI core xfmr than toroids. in any event, i havent found ringing to be a significant issue.

Do you mean that it is useless in EU or that the ground loop breaker should be wired differently?

an electrical code/safety issue --
 
I've just finished my phono stage.
Great sound is coming from this little box. Added the cap in series with R14, I had to bypass R1,R2 and R30, R32, otherwise it would not start (don't know why).
Thank you Wayne for making this happened and 6L6 for guiding me with your tutorial.
 

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I'm going to lead you all Wayne Colburn.
"The red reference LED we use is a Everlight MV50640 Gallium Arsinide. Not super critical."
Greetings to all. A channel runs with 2mA LED, if that is good? A channel is difficult to evaluate anyway. One thing I notice is that all instruments are not miscible, that are all pressentz in the room.
 
Hello together, both channels "breathe" already. Only without chassis and powered by batteries. From the beginning had the less bass and amplification. I had as well as in the guide of Wayne, Capazitors C16 and C12 from two 0.1mkF to a 0.22mkF is now enlarged is bass enough. And instead of R15 short-circuit, I had built 33 ohms resistance, I did not understand that, but that actually broke to more profit, my guess so 6-8 dB. And I would have liked to know how much gain is in fact and whether the output transistor will not overload. Thanks and I apologize for language errors, I use only Google translator.
 
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Output snubber in chimpamp power supply

I've been working on all the power supplies in my Pass/FirstWatt components and have finally gotten to my Pearl II supply (I'm working on installing input snubbers).

The supply for the Pearl II incorporates a board from Chipamp.com which has onboard output snubbers. When I originally built the supply I populated the boards with the snubber parts. It occurred to me that I really didn't need these parts, so while I had it apart I pulled them out. I put the supply back together because my brother was coming over and we were going to "spin some tunes", so there are no other changes to the supply.

When I put the Pearl II back in the system I had no expectation of a sonic difference so I was really caught by surprise because there's a huge difference, this thing sounds way different. Not a subtle difference, but a two grooves in jaw hitting the floor kind of difference.

Can somebody explain to me what in the world is going on here?