RJM Audio Emerald Phono Stage Help Desk

Thanks Richard. I soldered the Green/Yellow shield wire to ground. It was dead silent without that connection, but I might as well use that feature.
All but one of PT's I used in the guitar tube amps I built over the last year didn't have shield grounding (the Allen Amplification PT being the exception) and they are quieter than new store-bought amps. But, nobody really cares about a bit of hum and hiss with guitar amps!
 
Thanks for the clarification.

Perhaps it's would be nice to have some basic knowledge of electronics before getting in to this diy-stuff. But it's very fun and I'm learning. I believe I've already upped my soldering skills and it no longer seems so intimidating :)

I remade my sketch and the DBRB wiring should be correct now on both sides.
I'm still not quite sure what to do with Blue & Brown jumper cables? The Grey stays unconnected?
 

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Looks very nice! Where are the cases from? And what is the amp on the side?

Happy listening! :)
The cases are hammond 1444 8x6 aluminium chassis. They are hand painted with hammertone.
The little amp is a TA2024 board from Sure electronics.
I tried to keep everything to look coherent.

Once everything is fastened, I will plug it to my minidsp shd/hypex nc400, but it did sound already very nice with the ta2024.
 
Hi all,
Well, I've been playing through the Emerald for about three weeks now, and I've had the Grado Timbre Opus3 installed for a little over one week.

This is the best my records have ever sounded since I first started buying them around fifty years ago.

It's amazingly quiet between songs and on quiet passages. I'm getting great dynamics and a very balanced FR: deep, solid bass and clear, crisp highs, but definitely not bright or harsh. The midrange seems alive: very warm, rich and full.

I feel like I really lucked out. I'm getting the sound I've always wanted from my system, the sound I imagined in my head, if that makes sense.

So, I'm totally - more than - satisfied with the way the Emerald and the Opus3 are working together with my Tubelab SSE tube amp and the Fostex 4" FE108EZ Sigmas in my Buschhorn MKIIs.

On top of that, the Emerald (with two enclosures) completely built was around $250. What an incredible bargain. Plus, it was great fun to build. And, I can take pride in the fact that I built my speakers, amp and phono stage.

Thanks Richard for a first-rate project. I recommend the Emerald to anyone who wants an easy to build, great sounding phono stage that's very affordable.

David
 
I’m getting closer now. The last two Mundorf capacitors are on the way and then I’ll get the case from Modushop.biz. I’ll fit the smaller psu case inside the other.

In the meantime, how do I test to see if everything is working as it should? I’ve already tested the psu and it outputs 12.5 VDC.
 

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Hi

Just want to make sure my understanding is correct with the switchboard in place.


If R1 is set to 100k on the Emerald with both jumpers open, and R1 is set to 87.7k on the switchboard. Am I correct in thinking that if R1 on the switchboad is off, the cartridge load will be 100k and if R1 on the switchboard in on then the load will be just shy of 47k.


Thanks