Output impedance?

[tombaker]

Hi All,
I'm wondering if there's anything I need to do to my circuit to prepare it for this 600ohm coupling output transformer:
http://www.ebay.com.au/itm/400423344112?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Here's the circuit:
https://www.dropbox.com/s/r0xjbe81a36hagl/unbalanced-lav-pre.png

It's an uber simple mic pre for a lavalier mic with 2 stage HPF.
Thanks

[GibsonGM]

I don't truly know the 'right' answer, Tom, but I would say you are ok.  The "ideal" opamp output would have zero Zo; in the real world, there will be SOME.   Whether that is 20 ohms, or 100 ohms, I'm not sure.   But, I think a mismatch of a few hundred ohms won't be noticeable to you.   If you were going 600:10K, then I'd DEFINITELY say you're ok, ha ha.   

I'm not seeing any side-effects that couldn't be fixed pretty easily, even by a series resistance of like 330R.    Someone more knowledgeable than I will probably chime in and give more a more defined answer for you!   

[tombaker]

Awesome, thanks. i may end up going with the 600:10k as this is a custom set of pres for a Zoom h4n an i think they function at -6dB below line level

[GibsonGM]

Have you done any kind of sim on them, LT Spice etc?  That may give you more of an idea of what a good match would look like.   At any rate, I'd go ahead and try the 600:10k, assuming the Zoom that you're running into has an input impedance that's at least marginally close to 10K....

There are other forums that deal more with PA stuff, and I bet you'd get a fast answer on them!  Sorry; my experience (and most others here) would be with OT's on tube amps, etc.  Where "close enough" is usually OK.    I can ASSUME you'll be ok, but not positive.  As always - exact impedance match is best for lossless transmission, but is very often just not obtainable...   

Me - I'd try it, ha ha!

[CodeMonk]

Sorry, I don't have an answer.
I just really like your user name.
Tom Baker is my favorite doctor of all time. And the first time I ever watched Dr. Who, it was him

[tombaker]

Thanks for the help and the name kudos - i'll pass them on to my parents. haha.
I think these transformers are more suited to microphone input but i get on diyaudio and see what they say.