Driving a 600R LCR RIAA stage

[IslandPink]

Better get a roll of mu-metal sheet if you're buying Dave's chokes

[Keith Haywood]

Island Pink Wrote:
"Better get a roll of mu-metal sheet if you're buying Dave's chokes

Yes, see how the land lies, then look at that problem if necessary!

What plans did you have for shielding those for the Slagle kit LCR?

Keith

[IslandPink]

I have a die-cast aluminium box for all the chokes, plus a sheet of 0.1 or 0.2mm mu-metal I got from a guy at work. I intend to attach each pair of chokes to an aluminium base piece ( strip ) , chokes 90 deg to each other, then put a cylinder roll of mu-metal around each pair before installing them into the box. Whether this will be enough I don't know !

Nick - are your LCR chokes on the PCB's ? - I was looking at the internal pics on reviews and not quite sure. There are some grey box-like things there.

[izzy wizzy]

Maybe a dumb question but Sowter and other transformer manufacturers stick their what nots into mu metal cases. Why is this mu metal screening thing so difficult?

cheers,

Stephen

[Nick]

I have a die-cast aluminium box for all the chokes, plus a sheet of 0.1 or 0.2mm mu-metal I got from a guy at work. I intend to attach each pair of chokes to an aluminium base piece ( strip ) , chokes 90 deg to each other, then put a cylinder roll of mu-metal around each pair before installing them into the box. Whether this will be enough I don't know !

Nick - are your LCR chokes on the PCB's ? - I was looking at the internal pics on reviews and not quite sure. There are some grey box-like things there.

No, the chokes are in the S&B shielding cans. The grey things are caps.

[thomas]

I have a die-cast aluminium box for all the chokes, plus a sheet of 0.1 or 0.2mm mu-metal I got from a guy at work. I intend to attach each pair of chokes to an aluminium base piece ( strip ) , chokes 90 deg to each other, then put a cylinder roll of mu-metal around each pair before installing them into the box. Whether this will be enough I don't know !
.

I did something very like that for some Hammond anode chokes and it did cut down some audible and (measurable, albeit crudely with a dvm) hum so definitely worth a go…..

[Keith Haywood]

Hi all

I know Dave Slagle is offering some solutions (MU metal can via external firm?), but not sure exactly what. Hope to find out when I know if if he is still able to supply a set for S.Bench LR phono stage. Certainly easier with LCR, and especially in a box (Audio Dimension/Tango, Silk etc). I realise it would be easier allround to get the Sowter set (have their excellent custom OPT's in my valve amps, and not far from me), but for the S.Bench LR, my gut feeling is the Slagle will have the edge, especially with his SUT's to suit.

I must stress it is not my intention to use the original power supply, especially those cheap toroidal trannies! I would also very much like to try a CCS/VR shunt reg as Mark has previously suggested. Is it possible to get the PCB's for the Gary Pimm CCS/Reg? I may even try a Lundahl choke/ASC PP in oil cap to each valve/primary?

Thomas
Last year I read wih interest about your phono projects, where are you now with your own D3a phono stage?

Keith

[thomas]

Hi all

Thomas
Last year I read wih interest about your phono projects, where are you now with your own D3a phono stage?

Keith

Hi there!

D3a phonostage made a comeback, on the 'reloaded 'thread…...

[IslandPink]

Is it possible to get the PCB's for the Gary Pimm CCS/Reg?
Keith

Not recently, but I think it's likely Gary made the PCB data available somehow. I will try & contact him if I can remember. If you were to arrange a few PCB's to be (re-)made, I'd be in for a couple or 4 . It was the Self-Bias CCS's that are the most handy.