Lundahl LL1540 as output transformer?

[ln76d]

Hi Guys,

quick question
Does anyone used ll1540 input transformer as the output?
If so, did it do the job? How did you wired it? Like the standard 1:1 input or reveresed?
Am thinking to use it for direct outputs for microphone preamps.
http://www.lundahl.se/wp-content/uploads/datasheets/1540.pdf

 

[gyraf]

No can do. Way too high copper resistance..

Jakob E.

 

[ln76d]

No can do. Way too high copper resistance..

Jakob E.

Thank you Jakob as always for help 
I missed that in datasheet, i'm in rush all the time

Probably i will invest in more of ll5402.

Here's a great answer from Lundahl (great custom service!) for educational purpose 

An audio line is a cable transferring an audio signal from the output of
one device to the input of another. Normally the input impedance is fairly
high, >1k for mic preamps and >10k for line inputs.
If the impedance in both ends of an audio line are high, any noise current
picked up by the cable will be easily audible, as the current will generate
a significant voltage across the input resistor. But if one side is low
impedance, the noise current will be short circuited and no voltage will be
generated.
Even if the impedance of your output amplifier is fairly low, the use of an
LL1540 will add almost 3k to the output impedance, which in most situations
is far too much. In addition to the noise problem above, you will also get
a certain signal loss across the LL1540, in particular if the input impedance of the next device is less than 10k.