looking for toroidal equivelant to transformer

[phreeky82]

i have built two kit amps and run them on their own transformers and power supply circuits.

the kits are here: http://www1.jaycar.com.au/productVi...&pageNumber=&priceMin=&priceMax=&SUBCATID=557

basically, the transformers are CT 28v secondaries (240v primary). the power supply kits output +/-40v. the way this works etc is of no problem to me, i understand all the theories.

now i'm also guessing that if i buy a toroidal that has two secondaries of 25v, i can wire them in series, with say wire A of the first secondary being 'negative' 25v, wire B of the first and wire A of the second being 0v, and wire B of the second being 'positive' 25v. but that's about 6vrms less power i'm feeding it. that means less power, doesn't it? i don't think i'll find a toroidal of 28v secondaries, but i don't know wether i'll be able to find one with 30v secondaries either (which i guess the amp SHOULD be able to handle).

my main reasons for changing to a toroidal are:
- magnetic fields
- single toroidal for 2 channel amp
- lower profile

I would really appreciate any help. i also realise it is basically impossible to tell me whether the amp will be able to handle more than 28v CT, and the power supply for that matter too, but i am willing to take a slight risk.

 

[travis]

http://www.toroid.com/standard_transformers/rectifier_transformers/rectifier_transformers_117V.htm

 

[supa-roo]

If you use a single transformer, on the SC480 , still use 1 bridge and set of filters per channel. rather then one set and then split the DC rails off to each amp.

 

[phreeky82]

cheers man, but yeah i had figured that.

found a toroidal, 30v+30v 300VA, should do fine considering the transformers are rated at 28v CT 135VA. would have been cheaper to buy this toroidal straight up too, but i guess now i have two spare transformers

 

[Greg Erskine]

Hi phreeky82,

Here is where I get my toroids in Sydney.

http://ourworld.compuserve.com/homepages/harbuch/

I bought two 28VAC 160VA two weeks ago at $40.90 each plus GST. The frieght may be expensive though?

They have a large range and have hundreds in stock. I bought about 8 so far and have been very happy with the product. Cheaper and better than Jaycar, Dick Smith etc.