I’d have preferred it to have gone somewhat smoother 
Yeah it was first out of the box so was playing for a week or so while I unpacked all of the other stuff
It’s nice enough but I prefer other decks
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Do. Not. Talk. To. Me. About. Earthing.
Simply put, it’s a cunt. And yes, there’s no rhyme nor reason to it. It’s just depends how all the earths happen to interact. Ideally you want the signal ground connected to earth at one point in the system. Arranging that in practice can be, erm… challenging, as you usually have no idea what’s connected to ground via what, e.g. interconnects to other components, mains earth bonds in components, etc.
Anything with an M7 seems to be a especially cunty to get right.
Mostly, it seems you need goats, candles, a black mass, lots of trial and (mostly) error. Do you chain them, star them, whatever. 
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I honestly don’t think it can be solved with logic.
Trial and error is the only way I ever succeed in eliminating it.
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Oh, the blessings of digital…
I’lll get me coat.
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It’s not so hard to design a single end-to-end system where noise from the earth arrangement is negligible, although I have seen quite a few amps where it’s been done surprisingly badly.
The problem comes when we want to connect multiple independently-designed subsystems together. It’s a situation crying out for a standard. But that boat sailed 70-80 years ago.
VB
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Been playing around with the Yves Cochet PP-UN (head amp) today. Surprisingly good and very quiet. I believe Graeme (@Valvebloke) repaired/serviced it at some point?
Indeed, back when it was Jake Mortlock’s and following a little ‘accident’. I really don’t do solid-state stuff, but he had left a very nice valve pre with me and I said I’d look at the Un on the off chance I could fix it. Quite a lot of silicon had gone west but, fortunately, all the blown devices were still available. I’m sure you won’t be tempted to open the power supply up and disconnect anything. But if you do it’s critical that every last mechanical part goes back where it came from. Some of them are doing electronic as well as mechanical jobs.
I was impressed with it. It was very quiet indeed (then again I work wth valve kit …).
VB
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I won’t be opening it up 
I don’t suppose you have any specs for it? Or a circuit diagram?
I must have the circuit somewhere - I’d have needed it to fix the fault. ISTR there’s a write-up either of the Un or of some similar Cochet item online. Let me have a rummage about in the workshop book.
VB
Thank you, Graeme.
I can’t seem to find anything on line.
I measured a voltage gain of x32 i.e. 30dB. It was linear up to at least 3.75mV RMS input (i.e. far beyond what MC cartridges put out) with harmonic distortion less than 0.1%, and all 2nd harmonic. The input impedance was 20ohms or so (measured at 1kHz). Measuring the hum and noise was tough. The head amp itself was a bit prone to 50Hz pickup from nearby magnetic fields, so it was much quieter when separated by tens of cm from any transformers, including the one in its own power supply (that’ll be what the umbilical’s for then !). When that was done I reckoned that at the output the 50Hz component of the hum, which was the dominant one, was below 10 microvolts RMS. All the other components were at least 20dB down on that.
It’ll take me a bit longer to find the circuit.
VB
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Strain gauge cartridge ftw.
Panasonic EPC451
Had this for years, first time I’ve tried it. It’s very nice indeed.
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Are you using the Panasonic decoder?
Yes, I blew the dust out of it and was pretty pleased when I switched it on and there were no flashing lights or burny things.
Fuck, is that what you need to make that cart work? 
No, it’s perfectly possible to do something simpler (and better).
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Do you have a design for it, Pete?
I am sure the box you slung together didn’t have all those bits in it