Building a Pearl 2

While this is somewhat contrary to what I'd said previously, changing C22 does make a difference. It sounds the best with nothing there, and the problem exacerbates the higher the value I put in (tried 100 and 150 pF). The Ortofon blue has a recommended load capacitance of 150-300pf, do you think I might be going above that with just the cables?
 

6L6

Moderator
Joined 2010
Paid Member
No... just leave everything as-is and leave C22 empty.

I didn't read your response correctly the first time - I doubt the cabling is more than 300pF, and if it does sound best with no loading capacitor, you've found the proper loading. :) :yes:
 
Last edited:
Those are off my invoice, but I check all the part numbers on the bags when the order came in, and the values printed on the sides match up.
 

Attachments

  • wima labels.jpg
    wima labels.jpg
    395.2 KB · Views: 273
  • point1caps.jpg
    point1caps.jpg
    299.1 KB · Views: 279
I think Curt Campbell uses an Ortofon Red cart with a Pearl2 built to Wayne's spec and has no issues, and I'm sure there are plenty more with this combo. Although I'm really not looking forward to setting up a cartridge multiple times, I might put my cartridge on a friend's spare headshell to eliminate my table from the equation and compare both of our P2s. I'm starting to think it might be a problem with my cartridge since it sounds like the same issue I heard with my friends P2 and my table/cart before I got my Pearl2 together. I still don't get why it sounds fine with other phonos, though.
 
I've recorded a sample of my table playing through an NAD pre-amp and my Pearl 2. Due to recording limitations with my audio-interface, I could only record the right channel. However, the issue is still easy to hear. I'm terrible at describing what I'm hearing, so hopefully this helps narrow down the problem.

Dropbox - Phono Sound Samples - Simplify your life

If there is a better hosting option for these files, please let me know.
 
I took a listen to both samples, at first try the issue wasn't clear to me which is further proof of how much of a horrible "audiophile" I am.
After 2-3 listens it was apparent that the Pearl2 sounded a bit "muffled" which is the best I can describe it.

One additional thing to note is that the NAD is a few dB louder than the Pearl2, which is surprising as the Pearl2 has more gain than the typical MM preamp.

I plugged in both WAV files into Audacity, and it indeed shows an issue.
The Pearl2 looks to be rolling off from 10kHz (or even slightly earlier).
I'll leave it to the experts to understand what may be causing this.

On the bright side, looks like your resonant frequency is around 10hz which is good, and it is a bit more dampened on the Pearl2 (likely due to Waynes subsonic filter).
 

Attachments

  • NAD.png
    NAD.png
    78.1 KB · Views: 312
  • Pearl2.png
    Pearl2.png
    77.6 KB · Views: 311
It looks more to me like the Pearl has an flatter roll off and the NAD has a slight bump up at 5K.

I don't think I'm seeing (or hearing) what you are. The Pearl 2 spectrum is on the right. What I hear and see there is that starting at 5kHz, the Pearl 2 starts to roll off. Beyond 14.5-15 kHz, there's just nothing at all. It kinda makes it sound like it's playing in another room or I'm underwater.
 
I hooked up my Pearl 2 to a friend's table with a Grado 8MZ cartridge and it sounded fantastic--no roll-off. It sounds nearly identical to his Pearl 2. The only differences between ours are that I built Wayne's PSU and he uses wall-warts, I omitted C22 whereas he has 100pf loading, and I use 990 Ohms vs his 909 for R12. I think my Pearl 2 is working as designed.

So why doesn't it work with my table/cartridge?

1. Is the stock Pearl 2 design just incompatible with an Ortofon 2M Blue?
2. Is there any way that the stock Rega cables on my Planar 6 are to blame?
3. Is there something wrong with my particular cartridge?
3a. If that's the case, why does it only have problems with the Pearl 2 and not either of the other phono stages I've used with it?

:confused:
 
Last edited: