Hello!
I can't seem to ground my turntable to the cairn boost phono stage without attaching the GND to one of the phono inputs. It massively reduces the hum but it doesn't entirely get rid of it (hum is only audible when there's no music and I turn it up a bit but it's still there in the background).
Any idea why the original GND isn't working? I've opened it up and the connection from the terminal to the board is fine.
Could it be that there is no earth wire on the kettle lead I'm using? It's not the original one as I bought it second hand and the lead is moulded so I can't check without cutting the wire.
Also is there any danger of damage to anything by connecting to the phono?
If I connect it to the GND on my old tuner it's similar to attaching it to the phono, perhaps a tiny bit less hum...could it be an issue with the deck itself?
Thanks in advance.
I can't seem to ground my turntable to the cairn boost phono stage without attaching the GND to one of the phono inputs. It massively reduces the hum but it doesn't entirely get rid of it (hum is only audible when there's no music and I turn it up a bit but it's still there in the background).
Any idea why the original GND isn't working? I've opened it up and the connection from the terminal to the board is fine.
Could it be that there is no earth wire on the kettle lead I'm using? It's not the original one as I bought it second hand and the lead is moulded so I can't check without cutting the wire.
Also is there any danger of damage to anything by connecting to the phono?
If I connect it to the GND on my old tuner it's similar to attaching it to the phono, perhaps a tiny bit less hum...could it be an issue with the deck itself?
Thanks in advance.
Photos of both the turntable internals and the phono stage would be of help. Without them it is difficult to understand the current situation.
Also the potential grounding of the cartridge metallic part (to signal ground pin or headshell or both) may have its effect.
What does it mean "isn't working" - too much noise (hum)?
Also turntable model would be nice to know.
A separate (from signal cable) ground wire from turntable is usually connected to a grounding post on phono amplifier back panel (judging from interent pictures Cairns seems to have one also).
Inside the turntable that ground wire should not be connected to signal wires.
Being on the other side of the Atlantic I'm not sure what you mean by "kettle lead". Is that the power cord? If so, you might try ohming-out the earth connection on the plug. Hopefully that term isn't peculiar to this side of the water 
.
It also would be interesting to see if the hum changes if you unplug the TT.
.It also would be interesting to see if the hum changes if you unplug the TT.
IEC 60320 is the standard, actual kettle lead uses a C15 plug, but for low temperature devices like audio equipment the C13 plug is normally meant, commonly called a kettle lead although it will not fit a kettle which only mates with a C15 high-temperature plug. A true kettle lead will plug into a C13 socket though, so can be used at a pinch. https://en.wikipedia.org/wiki/IEC_60320
Thanks for your responses.
The deck is a Kenwood KP5022, which has it's own ground terminal an as does the Cairn boost phono stage. If I ground in the traditional way between these 2 terminals the hum is overbearing and interferes with the music but if I connect from the turntable's grd terminal to one of the phono inputs it's much less.
I've used the head and cartridge before on another deck and it's perfect, although I can't vouch for the Kenwood too much as I bought it on eBay. (sounds great though, mainly)!
I'm loving the trans Atlantic cultural wire exchange and to be fair I don't think these leads have been used on kettles since 1983! It's a c13/14 from the link above and fits the socket on the phono stage perfectly. When you say ohm-ing out would that entail putting one end of the multimeter on the female end of the plug and the other on the earth pin of the plug...and if it showed 0 ohm then there's no earth?
The noise is still there if I turn off the deck and just have the phono stage on. Does that mean the fault is most likely with the phono stage and if so what do you think it could be?
Was also thinking that it could be feedback of some sort as the turntable and speaker are less than 2ft away fro each other on the same table. I have put them both on separate bits of thick foam to try and decouple them but that's as far as my knowledge goes on the cart and speaker interacting with each other negatively. Surely if it was that then it would stop when I turn the deck off (which it doesn't)?
Appreciate everyone giving me their time on this...as an Englishman I should probably put the kettle on now...
The deck is a Kenwood KP5022, which has it's own ground terminal an as does the Cairn boost phono stage. If I ground in the traditional way between these 2 terminals the hum is overbearing and interferes with the music but if I connect from the turntable's grd terminal to one of the phono inputs it's much less.
I've used the head and cartridge before on another deck and it's perfect, although I can't vouch for the Kenwood too much as I bought it on eBay. (sounds great though, mainly)!
I'm loving the trans Atlantic cultural wire exchange and to be fair I don't think these leads have been used on kettles since 1983! It's a c13/14 from the link above and fits the socket on the phono stage perfectly. When you say ohm-ing out would that entail putting one end of the multimeter on the female end of the plug and the other on the earth pin of the plug...and if it showed 0 ohm then there's no earth?
The noise is still there if I turn off the deck and just have the phono stage on. Does that mean the fault is most likely with the phono stage and if so what do you think it could be?
Was also thinking that it could be feedback of some sort as the turntable and speaker are less than 2ft away fro each other on the same table. I have put them both on separate bits of thick foam to try and decouple them but that's as far as my knowledge goes on the cart and speaker interacting with each other negatively. Surely if it was that then it would stop when I turn the deck off (which it doesn't)?
Appreciate everyone giving me their time on this...as an Englishman I should probably put the kettle on now...
Apologies for my belated response, we were visiting my 99 YO dad for a couple of days.
Ohming out is a term that is used when checking for continuity. So in this case measuring zero ohms from one end to the other is a good thing.
I'm not quite sure what you mean by connecting from the turntable's ground terminal to one of the phono inputs. Are you referring to one of the signal inputs? If so, you're grounding the signal line and that suggests you may have a problem with your phono cartridge connections (in other words, the hum is coming from the cartridge or cartridge wire(s). One other possibility is the ground connection at the end of the phono arm. I recently worked on an old Dual 1019 that was fitted with a Shure cartridge and it had a bad hum problem that turned out to be the result of incorrect connections at the cartridge.