Home Tube DIY Asylum

Do It Yourself (DIY) paradise for tube and SET project builders.

RE: Operating SE trans just at limit current...

Hi Somejoe:

If available you really need the advice and knowledge of the builder of your iron. Here is why;

there is a lot of confusing ways to state dc current values and limits on a SE output transformer.

Some companies print a large number and call it--- Maximum DC current or such. But this number uses ALL of the available flux density of the transformer--- leaving no magnetic headroom for the AC signal. It is or can be essentially a measure of how much DC current by itself the trans can absorb before reaching it's saturation point.

You'll note that some companies publish a BIG dc current number--- but do all of their own testing at a much smaller DC current level. this is in practice the real dc current level that the trans will comfortably support if you value fidelity.

Not picking on anyone or any company--- but as an example--- look at some Tango specs for SE outputs. They will print a larg MAX value of DC current--- but when you look at where they test the unit it is most times at about half of this value.

Any transformer only has a certain amount (call it X) of flux density available. If you consume all of this flux with the dc current then you will have little or no capacity for the transformer to handle the AC (your music).

Another good clue to use--- is see if the manufacturer shows under what conditions they get their advertised L figure. Use that as a moreso reliable guide as opposed to just using the max number that may be printed.


This post is made possible by the generous support of people like you and our sponsors:
  Kimber Kable  

Follow Ups Full Thread
Follow Ups


Post a Message!

Forgot Password?
Moniker (Username):
Password (Optional):
  Remember my Moniker & Password  (What's this?)    Eat Me
E-Mail (Optional):
Message:   (Posts are subject to Content Rules)
Optional Link URL:
Optional Link Title:
Optional Image URL:
Upload Image:
E-mail Replies:  Automagically notify you when someone responds.