bit late now but i think you have your prices wrong. it comes out at £92.4 all in for the two transformers from Airlink inc vat and delivery.
have a look at Troidy transformers in Poland superb prices but can take a week or so to get here but worth it.
for 2x 200va with band and screen its around £87 all in inc postage. if they must be 160va then give them an email or phone (they speak English). 2x 150va is around £76 all in so 160 should be between the two prices.
i had 2x 60va 2x12+1x7 custom made form me with my specifications about wiring placement and they came in at £92 all in to my door.
have a look at Troidy transformers in Poland superb prices but can take a week or so to get here but worth it.
for 2x 200va with band and screen its around £87 all in inc postage. if they must be 160va then give them an email or phone (they speak English). 2x 150va is around £76 all in so 160 should be between the two prices.
i had 2x 60va 2x12+1x7 custom made form me with my specifications about wiring placement and they came in at £92 all in to my door.
Just a quick note on the EMI shield option:
What you need will depend on how you are planning to build your amplifier.
Class II (double insulated), as typical for hi-fi gear: EMI shield winding is very much recommended for minimum mains coupling. Connect to power supply ground. This should keep ground loop issues to a minimum.
Class I (safety earthed), as typical for PA/studio gear complete with balanced connections: Shield winding is optional. Here circuit ground is tied to PE anyway, and coupling over the transformer would not be relevant up to shortwave frequencies. Class I devices also tend to be more foolproof to build.
Note that in any setup using unbalanced interconnects, there must never be more than one earth/ground connection if you want to avoid ground loop issues that would have to be tackled by galvanic isolation. If you use up the one connection for your power amp, you will not be able to simply connect an ordinary PC to it as a source and expect it to work without annoying ground loop noises.
The pro/studio world is the exact opposite with everything being grounded, but of course they have balanced connections that will reject common-mode noise.
What you need will depend on how you are planning to build your amplifier.
Class II (double insulated), as typical for hi-fi gear: EMI shield winding is very much recommended for minimum mains coupling. Connect to power supply ground. This should keep ground loop issues to a minimum.
Class I (safety earthed), as typical for PA/studio gear complete with balanced connections: Shield winding is optional. Here circuit ground is tied to PE anyway, and coupling over the transformer would not be relevant up to shortwave frequencies. Class I devices also tend to be more foolproof to build.
Note that in any setup using unbalanced interconnects, there must never be more than one earth/ground connection if you want to avoid ground loop issues that would have to be tackled by galvanic isolation. If you use up the one connection for your power amp, you will not be able to simply connect an ordinary PC to it as a source and expect it to work without annoying ground loop noises.
The pro/studio world is the exact opposite with everything being grounded, but of course they have balanced connections that will reject common-mode noise.
Thanks Bibio, I should've mentioned that I live 10 minutes from Airlink and picked them up personally so no postage or vat on postage. I plumped for the 160va without any shielding, will see what happens with the hum when I get the kit together.
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