Well after very very long 6 year break I am back to get this finished.
Years ago I pretty much finished populating the Pearl boards. I already have a B1 buffer up and running for years.
I have the transformer and the LM3886 power supply that is somewhat built.
I just need to try and find all the changes that have been made in regards to components used on the Pearl and power supply boards. Plus go back and see how everything is supposed to connect with each other, man does that sound bad.
My plan is to get a box for the transformer and power supply to keep them a few feet away from everyone else.
I plan on putting the B1, Pearl 2 along with a motor controller system I picked up from Bill Thompson into the chassis I had picked up from 6L6 years ago.
So it is back to having fun.
Years ago I pretty much finished populating the Pearl boards. I already have a B1 buffer up and running for years.
I have the transformer and the LM3886 power supply that is somewhat built.
I just need to try and find all the changes that have been made in regards to components used on the Pearl and power supply boards. Plus go back and see how everything is supposed to connect with each other, man does that sound bad.
My plan is to get a box for the transformer and power supply to keep them a few feet away from everyone else.
I plan on putting the B1, Pearl 2 along with a motor controller system I picked up from Bill Thompson into the chassis I had picked up from 6L6 years ago.
So it is back to having fun.
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I've been planning to do this for a while and have finally found the time to rebuild my Pearl 2 with an internal power supply. I used an Antek AN-0225 25v 25VA transformer followed by a Salas BiB v1.3 regulator. I used 3R bias resistors for a 200mA supply for each rail. The mosfets make the floor of the chassis a few degrees above body temp and the transformer warms up a little too, but not as much as the chassis floor.
I was a bit nervous about having a transformer inside the chassis, but it turned out well. I rearranged the PCBs to keep the input signals as far away from the AC wiring as possible. This worked well with no increase in noise at all. Now I can ditch a separate power supply box, so I get a space back in my audio rack.
My ongoing thanks to Wayne for such a great phono stage! Running my SL-1200 into the Pearl 2, then to a B1 Korg, into a MoFo amp and my FHXL speakers really makes a GREAT combination - lots of synergy with this setup! 🙂
I was a bit nervous about having a transformer inside the chassis, but it turned out well. I rearranged the PCBs to keep the input signals as far away from the AC wiring as possible. This worked well with no increase in noise at all. Now I can ditch a separate power supply box, so I get a space back in my audio rack.
My ongoing thanks to Wayne for such a great phono stage! Running my SL-1200 into the Pearl 2, then to a B1 Korg, into a MoFo amp and my FHXL speakers really makes a GREAT combination - lots of synergy with this setup! 🙂
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Eric:
Please explain the setup for the resistors r21 thru r24 (I can't see it clearly at the photo). What is the the attached component ?
Please explain the setup for the resistors r21 thru r24 (I can't see it clearly at the photo). What is the the attached component ?
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I added an additional 10R to the existing source resistors for a total of 20R. I was having a problem with my 5mV MM cardridge overloading and causing distortion. A few people here have commented that this was the wrong approach, so my next step is to return these to 10R and use the approach that Mark did with a switch on R14. One step at a time...
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Mark: when you added you gain switch to R14, had you already added the electrolytic cap to the ground side of R14 to control output offset drift? Or do you just switch the resistor load to ground for R14 as per the original schematic?
I'm wondering if the addition of the cap will interfere with swiching gain by R14.
I'm wondering if the addition of the cap will interfere with swiching gain by R14.
Eric -- you might want to consider using a "ground-loop-breaker" rather than directly connecting the ground planes of the P-II pcb's to the "green".
I think one design is shown on the F4 power supply schematic.
I think one design is shown on the F4 power supply schematic.
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Thanks, Jack - I'll give it a try and see what difference it makes. For the first iteration, I just directly connected everything to see if it caused any problems...
Hi Eric, I'm not familiar with the electrolytic on R14. I just replaced R14 with a switch. Works well, no noise.
Hi! Likewise, coming back to DIY after a long hiatus. I'm interested in building the Pearl 2 but Bottlehead's Eros 2 (and, to a lesser extent, their Reduction) is also attractive. Which do you guys prefer?
Yeah, I probably should've led with my current setup: Debut Carbon table (with acrylic platter and Ortofon 2M Bronze cartridge); ProJect Phono Box 2 preamp; Naim Nait 5i integrated amp; Sunfire Super Junior subwoofer; Martin-Logan 35XT bookshelf speakers.
I also have Schiit Modi feeding the Naim for PC audio and a Schiit Modibit going toward a heavily-modified Bottlehead Crack amp for my Beyerdynamic T1 'phones. Ever since my wannabe-audiophile start, I've loved the brightness of Klipsch speakers (almost left the wife over a pair of KLF-30's. Almost.) So there isn't a part of my audio chain that I don't like.
After scouring the googles, I'm left with trying to decide whether the Pearl 2 (with tinkering...don't get me wrong, I love agonizing over parts lists just like any other wirebiter) or the Eros 2 would best suit my needs/desires.
Thanks again!
I also have Schiit Modi feeding the Naim for PC audio and a Schiit Modibit going toward a heavily-modified Bottlehead Crack amp for my Beyerdynamic T1 'phones. Ever since my wannabe-audiophile start, I've loved the brightness of Klipsch speakers (almost left the wife over a pair of KLF-30's. Almost.) So there isn't a part of my audio chain that I don't like.
After scouring the googles, I'm left with trying to decide whether the Pearl 2 (with tinkering...don't get me wrong, I love agonizing over parts lists just like any other wirebiter) or the Eros 2 would best suit my needs/desires.
Thanks again!
I don't know anyone who's built an Eros 2 and I don't see a lot of discussion about them. Maybe if you build one you can locate a Pearl 2 owner near you to do a shootout.
I doubt you could go wrong with either. Both are excellent designs.
One thing worth mentioning, the Pearl 2 is the quietest phonostage I own. (And I have more than a few... 🙂 )
One thing worth mentioning, the Pearl 2 is the quietest phonostage I own. (And I have more than a few... 🙂 )
Hi!
Any reason not to shrink the size of the PCBs? I`m considering making PCBs for SMT parts. I don`t have much experience in doing layouts, so I will not do it if there are strong arguments against.. I have collected some of the parts for the regular version as well, but have not start building yet.
Any reason not to shrink the size of the PCBs? I`m considering making PCBs for SMT parts. I don`t have much experience in doing layouts, so I will not do it if there are strong arguments against.. I have collected some of the parts for the regular version as well, but have not start building yet.
Hi All,
Rookie builder here and this is my first big electronics project.
I have received all the parts for my Pearl 2 build and the chassis as well. I am a little insecure about my parts orders of the resistors, they don't look the same as the ones used by other people. Mouser was out of the Vishay Dale that I see most people using, so I bought a different kind but with the same values. I did not know whether to order 1/4 watt resistors or 1/2 watt, so I ordered 1/4. Here's what some of the resistors look like, they are a lot smaller than others I was able to buy that are Vishay Dale and that most others have used. Did I order the wrong ones?
Rookie builder here and this is my first big electronics project.
I have received all the parts for my Pearl 2 build and the chassis as well. I am a little insecure about my parts orders of the resistors, they don't look the same as the ones used by other people. Mouser was out of the Vishay Dale that I see most people using, so I bought a different kind but with the same values. I did not know whether to order 1/4 watt resistors or 1/2 watt, so I ordered 1/4. Here's what some of the resistors look like, they are a lot smaller than others I was able to buy that are Vishay Dale and that most others have used. Did I order the wrong ones?
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Original Pearl phono pre & original Eros phono pre comparison
Links to some tests of these two phono stages:
Eros
Original Pearl
Links to some tests of these two phono stages:
Eros
Original Pearl
