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Old 4th January 2013, 08:47 PM   #1711
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It's been more than 1.5 years since I got the parts for my Pearl II and now I have finally started the project. To refresh my somewhat rusty soldering skills (not done something serious in over 20 years) I started with the power supply. This is the standard version as mentioned in the article by Wayne. Mine has a 2x 24V 50VA toroid in it, and the output is around 38V DC unloaded. Hopefully this will drop a few volts when loaded so the regulators will have an easier task.

I got HIFI 2000 enclosures for both the power supply and the Pearl II. Unfortunately I messed up the front panel of the power supply when making the hole for the switch, so I had to re-polish it. It does not look the same anymore, but fortunately it will be spaced apart from the enclosure of the Pearl II.

Some pics:

Click the image to open in full size.

and the inside:

Click the image to open in full size.
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Old 4th January 2013, 08:51 PM   #1712
6L6 is offline 6L6  United States
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Wow! That looks great!



Looking forward to seeing the rest of it!
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Old 4th January 2013, 08:59 PM   #1713
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Thank you! I hope the project will be a success and offer some audible improvement over the phono stage of my Sony TA-FA70ES (which I think is not bad at all).
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Old 4th January 2013, 09:08 PM   #1714
6L6 is offline 6L6  United States
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There is no doubt that ES is nice stuff.

You will like the Pearl better...

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Old 5th January 2013, 01:34 PM   #1715
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I'd like to have a bit less subsonic rolloff in my Pearl II (flat or -0.25dB at 30Hz, below 30Hz rolloff is fine). Wayne suggests increasing the value of C12. What would be a good value? 0.22 in stead of 0.1?
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Old 5th January 2013, 02:00 PM   #1716
6L6 is offline 6L6  United States
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I think you could change the value of the output cap to play with the LF rolloff... Make it smaller? I don't remember off the top of my head.

Somebody will chime in with info. Hopefully Wayne.
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Old 5th January 2013, 03:42 PM   #1717
AVWERK is offline AVWERK  United States
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Wellerman
I used .15 on my build and Wayne suggested that on the similiar original Pearl build, C11? from memory
You really want to stay away from table low freguency resonances 2,3 hz and the tonearm/cartridge 8/11 hz resonance. This combination is best not amplified with the huge gain availble here, and hence, the intended rolloff
I think Wayne mentioned he used on his pesonal pre, he used the low end fiter in the ON position (XP20?)

What is important just as much or even more is hum. If you are getting any at all, don't expect bass that will plummet down to the basement frequencys like it should with any kind of serious detail

Regards
David
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Old 5th January 2013, 04:52 PM   #1718
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OK, I'll try 0.15, I ordered a couple of those and 0.22 originally. Agreed that below 20Hz rolloff is welcome to dampen rumble, resonances and other unwanted stuff.
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Old 20th January 2013, 12:40 PM   #1719
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Well, here is a picture of what will be the right channel of my Pearl II:

Click the image to open in full size.
I still have to make some connections and then will check everything again before I dare to connect it to the PSU. And then hopefully I will get some voltages as they should be.

I left out C7 and C15, R15 is a jumper and I used 0.15 for C12 to get a bit less subsonic rolloff (I hope that will only influence the frequency < 50Hz as I do not want a loudness effect or something like that)
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Old 20th January 2013, 02:33 PM   #1720
6L6 is offline 6L6  United States
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Looks good!
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