Yes, I am trying to do this with minimal clutter and wiring.
For capacitance, I showed in this post (what I think is) a fairly elegant solution to adjust for various loads. Initially for AT MM, I will keep it empty, but will play with caps in the 50-100pF to see if any difference.
https://www.diyaudio.com/forums/pass-labs/204336-building-pearl-2-a-215.html#post6230571
For resistance, I'm thinking of a DPDT on-off-on per channel, right next to each input. This will result in 2 short wires to R20 pads from DPDT
OFF == open, default 47K.
The ON-ON will toggle in resistors to adjust for MC carts, perhaps 100ohm and 470ohm.
If you haven’t already bought your chassis, I used a 1U Galaxy by laying the 10K uF caps on their sides and finding 30 mm 3300 uF caps. The heat sinks aren’t a problem. You have to use short standoffs and still won’t have much clearance in the end but it will fit.i just really like the low profile.
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To fit 1U I ended up going with a slightly larger diameter for the 15Kuf caps and bent the regulator heat sinks to accommodate. Also, I’d advocate for bringing power right down the middle and using some kind of mu metal u-channel to shield the power wiring and create some separation between left/right channel.
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such a great work. well done. what exactly are those RCA connectors? if you could share a link id like to buy some. they seem good quality.
Thanks! They are Vampire connectors. Pretty pricey, but I started using them a while ago and have stuck with them since. Very nice, but certainly plenty of good options that cost less.
Vampire Connector CM2F/CB RCA Female Jack
I like Vampire RCA's, although I use the cheaper CMHEX.
BTW, check out Michael Percy, he has good prices on those
BTW, check out Michael Percy, he has good prices on those
Yeah, I’ve been thinking about switching to those for future builds. Does Michael Percy have website?
No website. Just a PDF catalog on his site which is mostly up to date. Order over email/PayPal.. generally pretty efficient.
Eichmann has a new venture (KLEI) and a new set of RCA connectors that look promising.
KLE Innovations RCA Connectors
I'm planning to try them on my Pearl 1 build.
KLE Innovations RCA Connectors
I'm planning to try them on my Pearl 1 build.
One thing I was wondering: does the mod with the cap in series with R14 to stabilize DC on the output have any effect on the sound quality (positive or negative)?
I used the mod to stabilize the offset so that I could remove the coupling cap at output. That made a positive impact IMO, but I can’t say if the cap/R14 mod alone would make a difference. It certainly stabilizes the offset, but that may be moot since any dc would get picked up by the output cap.
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Lots of decent RCA’s on fleabay too. I have a bunch of these I plan on using for my Pearl 2 build.
10 x CMC Gold Plated Copper RCA Female Phono Jack Panel Mount Chassis Connector | eBay
Made some progress with my PSU today.
10 x CMC Gold Plated Copper RCA Female Phono Jack Panel Mount Chassis Connector | eBay
Made some progress with my PSU today.
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My chassis is here and I'm ready to wire it up.
Regarding absolute phase, do you folks typically connect the input signal to input ground (on Pearl PCB) to correct it, or leave the output out of phase? Anyone tried both?
Regarding absolute phase, do you folks typically connect the input signal to input ground (on Pearl PCB) to correct it, or leave the output out of phase? Anyone tried both?
That's what I was thinking (though reversing leads at the speakers is the usual advice).
At the cartridge end the problem is that the cartridge shielding (if any) is often connected to one "ground" pin and would then be wired to the "hot" pin in the Pearl. You'd have to see if you could lift that shield and wire it to ground separately... I think.
I could be wrong.
At the cartridge end the problem is that the cartridge shielding (if any) is often connected to one "ground" pin and would then be wired to the "hot" pin in the Pearl. You'd have to see if you could lift that shield and wire it to ground separately... I think.
I could be wrong.