which are<The Best> toroids?

[mecano]

Me and a friend are to build a state-of-the-art PSU for his Krell preamp. currently we are trying to decide which toroid transformer to use,the specifications are:
Primary 220V frequency 50 hertz
Dual secondary voltage 30+30 V
Secondary current 5,5 A-330VA
Since its a Krell preamp in a high-end system, thus the highest quality is indispensable

. We are between Hammond, Avel-Lindberg and Plitron
But which one is the best?

 

[BoyElroy]

You may want to post this on the www.diyaudio.com site. I'd guess that someone there would also have some info. on Krell's OEM transformer manufacturer (which might be a good place to start).

 

[antness]

I believe Plitron manufactures a power transformer for solid state amplifiers. very expensive i believe a few hundred for the transformer you need. Have no idea if they're worth the price...

 

[mecano]

I posted the question to diyAudio.com too-thanks BoyElroy.I m really interested in knowing what transformers the top companies (Mark Levinson,Classe,etc) use.I only know that Sonic Frontiers uses Hammond into its Power Amps…

 

[Voodoochile]

My Parasound Halo stuff has Avel Lindbergh xformers inside, fwiw. I couldn't tell you how they affect the sound, though. It sounds very good, but I doubt it has much to do with the manufacturer, rather the proper selection of the current capabilities might possibly have more to do with it. The tranny in the amp is a 1kva piece.

 

[Doh]

I think some people at DIYaudio have had good success with Victoria Magnetics.

 

[mecano]

Well seems Plitron,is the one for us since this Canadian factory is building transformers for Classe/Madrigal-ML (info from the people at DIYaudio)
IMO the best SS amps in the world

 

[wallijonn]

http://www.worldtubeaudio.com/direct...tegorie_44.htm

I've been looking at Avel Lindberg, Amveco, Amplimo, Toroidal Corporation of Maryland, Plitron...

Piltron has some really good prices (choose US dollars at the bottom). Wonder what the postage would be for a 10 pound toroidal? (400VA, 9 amp. about $53). Pilton can customise a transformer, so a 757015201 becomes a 75A315201, this would then be 117VAC, magnetically shielded, electrostatic screened, 22v/22v, 9 amp, 5% regulation.

For Toroidal International you'll have to phone.

To forego postage, it might be easier to look for a local distributor and then just go and pick it up.

 

[wallijonn]

Mecano,

Piltron
077017201 is a 30/30 300VA/5A.
if all you need is a 115/230V 50/60Hz, you can get away with a code 7 (07"7"317201, or 077317201). see table below.

757017201 is a 30/30 300VA/6.67A
755317201 is a 100/120/220/240 30/30 300 6.67

http://www.plitron.com/pages/Products/Std/ratings.htm

http://www.plitron.com/pages/Products/Std/schemati.htm (WINDING SCHEMATICS)

 

[wallijonn]

this will show the different "pottings" available: http://www.amveco.com/Technical_Notes_6.htm

You should MEASURE the space available before ordering and match up accordingly.

if you know you really do need a 330VA unit, you may want to go up 1 or 2 grades (say to 530VA) for cooler temps, better regulation, and lower noise.

 

[mecano]

Wow,Wally thanks for all this info

!

The Krell preamp has a “C” core transformer-its high quality but too small(no more than 100VA).We are going to build a monster external PSU with 300-330VA and 2x15000uF.So the 330VA are already “up 2 grades”.
I also asked Victoria Magnetics and got this email from them :
<We can make the requested transformer for you for $62.00 plus shipping>
interesting if the VM build quality is superior than Plitron hmm..

 

[Gariver]

I will cast my vote for Canada's Plitron. If they are not the best, they are right up there in the top five. Here's the link...

http://www.plitron.com/

*

 

[PinkFloyd]

Nuvotem are favoured by UK audio companies such as Tag McClaren, Quad, NAD etc etc...

http://www.nuvotem.com/ Available from RS components Tony

http://www.rs-components.com/

Your friend

Pinkie.

 

[PinkFloyd]

BTW... how are the cerafines sounding in the Creek?? There are only 2 Creek amps in the world that have tonerex and cerafines on board. Yours is one of them and my old amp is the other.

Review pleeeeeeeeease.

Mike

(Pinkie)

 

[wallijonn]

mecano,

The price listed on Piltron are for an order of 5 minimum. there is a 50% surcharge for just 1 piece. In my case the toroidal would come to $90. I am giving it serious consideration, seeing as a lesser rating toroidal is going for $72 locally.

in your case, a Krell deserves it, don't you think? so paying US$80 isn't such a big deal.