Hummmmmmm ?

[Audio Al]

Sorry to keep posting

BUT

I have just noticed I get a Hum on my TT when I swing the arm over the record ?

And it reduces when I swing it away again

Its only slight but now I know its Happening :eek::eek::doh:

[YNWaN]

Do you have a Grado cartridge by any chance?

[Beechwoods]

Sounds like its picking up noise from the PSU. Do you have a MM cartridge? It's more obvious with them because they require more gain at the phono-stage than MC cartridges, so magnetic interference with the cart gets amplified more with the lower outer MM's. This is why people recommend removing the stock Techie PSU and putting it in an external case, even if you don't upgrade to a 'proper' aftermarket / external PSU, like the ones Paul Hynes makes for example.

[Audio Al]

Hi

Yes its a AUDIO TECHNICA AT120E MOVING MAGNET CARTRIDGE

[sq225917]

MM carts are higher output than MC they typically require 15-25db less gain, not the other way round. They are more susceptible to RF noise due to their construction. The Grados (moving iron) being about the worst of the bunch.

What arm are you using?

[Beechwoods]

Oops, got it the wrong way round. Slip of the keyboard :rolleyes:

[Macca]

Sounds like its picking up noise from the PSU. Do you have a MM cartridge? It's more obvious with them because they require more gain at the phono-stage than MC cartridges, so magnetic interference with the cart gets amplified more with the lower outer MM's. This is why people recommend removing the stock Techie PSU and putting it in an external case, even if you don't upgrade to a 'proper' aftermarket / external PSU, like the ones Paul Hynes makes for example.

If it was picking up PSU noise then all SL1200's would exhibit this problem. But they don't. I'd be more inclined to suggest a dodgy wire somewhere - headshell, probably. If using a stock headshell get rid and get a Sumiko.

[prestonchipfryer]

Sorry to keep posting

BUT

I have just noticed I get a Hum on my TT when I swing the arm over the record ?

And it reduces when I swing it away again

Its only slight but now I know its Happening :eek::eek::doh:


It could be a slightly loose headshell wire. Carefully disconnect them and use a contact cleaner (Deoxit, Kontak, isopropyl alcohol) and then make sure they are refitted snugly.

[Audio Al]

Its a standard arm and head shell

[Macca]

Its a standard arm and head shell

Try one of these -
http://www.ebay.co.uk/itm/Sumiko-HS-12-Headshell-With-Litz-Cartridge-Leads-/170894124117?pt=Turntable_Parts_Accessories&hash=item27ca156455

may solve the problem but even if it is something else this will give you a big jump in sound quality compare to stock shell. I have done back to back - it is a substantial improvement.

[DSJR]

Grado's are notorious for hum pickup and Decca's can be even worse if you're unlucky. I didn't think the AT120E was a difficult one though, mine copes silently in the old Garrard AP76 it's in and sounds delightful in the flimsy old arm fitted..

If you're very careful, disconnect the mains from the deck and take a look under the platter. Once the cover is carefully removed, check all the earthing points to the chassis - tightness of screws etc.. Check the arm wiring terminal as well, where the external cables meet the tonearm ones, including the earth leads. Also, make sure the amp is as far away from transformer influence, as hum fields seem to be cummulative, one adding to another etc... It's a good thing to remove the Techie transformer and place it remotely, even before all the faff about a sooper-dooper add-on supply.. I'd suggest a call to Richard at Vantage Audio, as he may have ideas on the stock techie for minimising or eliminating this :)

[Audio Al]

Try one of these -
http://www.ebay.co.uk/itm/Sumiko-HS-12-Headshell-With-Litz-Cartridge-Leads-/170894124117?pt=Turntable_Parts_Accessories&hash=item27ca156455

may solve the problem but even if it is something else this will give you a big jump in sound quality compare to stock shell. I have done back to back - it is a substantial improvement.


Thanks

Will order one and see what happens :)