silly trafo question - any audio use for this one?

[smallbutfine]

ca. 10:1, frequency response measured here:
http://www.psychotrop.de/groupdiy/trafofreq.png

i had not the time to measure more, just let rmaa do a test...(the green one)
this one is sooo cheap, i just wonder if there could be any use of it? :grin: :?
any opinions?

:thumb:
kind regards

Martin

 

[CJ]

That might be good in a vocal mic pre, where you want both ends to roll off.
But not for micing instruments with a lot of bandwidth, like bass and cymbals.

People have been getting away with murder around here with cheap....err...lets say....inexpensive transformers, so you just never know. Plug it in and see.

If no good, it would make a great sinker for lake trout in August.

 

[gyraf]

Martin,

For the frequency response plot to make real sense, we'd need to know source and load impedances as well as if the transformer was used 1:10 or 10:1

Jakob E.

 

[smallbutfine]

wow, prominent members answering here when it comes to xfmrs.:grin:
thanks alot for the fast responses.
OK...it was a quick shot.
i hope i understand you right, Jakob (transformers are relatively unknown land to me...). I have no "real" measuring equipment here (only DMM and soundcard), so i did the following:

the xfmr has no center tap.

the signal chain was like this:

soundcard out (-15dB levelled test signal to meet -1dB on the soundcard in), 100Ohm (specs soundcard)

-> 1:10 -> xfmr

12kOhm (spec soundcard)
soundcard in
(met the -1dB to make the rightmark audio analyzer happy)

i hope this makes some sense to you.

CJ:

That might be good in a vocal mic pre, where you want both ends to roll off.
But not for micing instruments with a lot of bandwidth, like bass and cymbals.

That was exactly the first impression to me looking at the freq response curve. :shock:
(so i'm not *that* false thinking of it as an audio xfmr)

Since it cannot be used as a balanced to unbalanced xfmr (no center taps) maybe it can be used for a synthie line amp input...hmmm.
i have two of them.
i wonder what kind of pre (a groupdiy project?) would be possible with this.
maybe of use as a coloring output xfmr?
:?
you have much more experience with that than i have....

any thoughts appreciated...

thanks again and happy diy

Martin

 

[gyraf]

Try with a 220R resistor in series with your audio source output - that will bring your source impedance up to around a predictable 300 Ohms (sound card specs are often very inprecise).

The first curve - with 100R source/12K load points towards a quite low inductance in the "1" side of the 1:10 - probably making this transformer unusable for any low-end transfer if asked to work as 1:10 input transformer.

Also try measuring it as 10:1 - that will probably give you a much better freq resp. An use for a 10:1 could be in e.g. the output of a tube mic or similar..

Jakob E.

 

[Samuel Groner]

The 12k load sounds a bit low to make a serious judgment, no?

Samuel

 

[CJ]

Another use might be a DI box for guitar. I built one from a real cheap Prem transformer, 300 cps to whatever, and it fit the ticket. Full spectrum DI boxes can sound kind of "acoustic" with electric gits.

cj