What is an 'audio-grade' toroidal transformer ?

[ash_dac]

Hi,

What is an 'audio-grade' toroidal transformer ?

Hi-fi equipment manufacturers , forum members, and toroidal manufacturers refer to 'audio grade' transformers but I can't find any threads on the power supply design area on what one actually is!

Is it worth buying any of the generic non-audio toroidal transformers for use in audio projects ?

 

[EC8010]

One with a 50% surcharge on the price?

Seriously, possibly one operated at a lower flux density to reduce leakage and to allow for those horrible capacitor input supplies audio is stuffed with.

 

[flg]

Are you sure they are reffering to power supply transformers
And not audio signal transformers? Generally, to get the frequency response required by audio, very thin laminations of special alloy metals are used. In a toriod, that would mean a "tape" transformer. Very thin ribbon used as laminations on a round form. I would bet most of the power transformers that are very large toriods, are tape wound cores anyway. Ferrite would probably need to be very large at 50-60Hz to not saturate

 

[ash_dac]

Hi,

Sorry I was meant audio grade power / mains transformer.

 

[AndrewT]

Hi,
this might help
http://www.diyaudio.com/forums/showthread.php?s=&postid=996215&highlight=#post996215
from a few days ago.

 

[poobah]

audio grade = mountain grown coffee

(all coffee grows in the mountains)

 

[jacco vermeulen]

which one is audio grade coffee ?

 

[cerrem]

Audio Grade usually refers to the core material used...
Most likely M6, which is a grain oriented material that is in strip wound typically .014" thickness strip...
The Sat point is roughly 18K Gauss...But good audio design is to set the peak flux density at 10K Gauss at 20Hz at full power output....Keep in mind that is not frequency response of transformer...This is for keeping the core distortion under a specific %......
Peak inductance will usually occur around 13K Gauss for that steel..

Chris