Can I use a step up transformer?

What yogiboy and Al said.  The ideal gain structure lets you run toward the end of your line stage's range - all things being equal (which they never are).

Now, from a noise floor perspective, it's possible that a step-up may help, but you'll be dealing with colorations (even with the best of step-ups) that are very possibly a trade-off you won't like.  You will be getting into yet another area where component matching will be critical. 

One overlooked attribute of a step-up transformer is that it works against you from a cable capacitance perspective.  You will have 100 (for a 1:10) or 400 (for a 1:20) times increase in capacitance (the square of the turns ratio) which may or may not matter, but is something to consider when selecting an output cable for your step-up transformer.

So (to equivocate further), it depends ...

Cheers,
Thom @ Galibier Design

Thom,
Just on the contrary. When I am using the Chinook with matching step ups this phono stage really starts to blossom.

Thank you all for responding. I knew I would learn some things by asking this question and I sure have from these responses. I really like the idea of not adding an additional component and more cables. Also, Things are dead quiet right now at these volumes ( I hate to inject anything that would impart noise). I like what Al and Yogi are saying about the volume knob being no big deal. To be honest, I play mostly everything around 12:00 position and pushing to 3 is really more than adequate, I guess i’m just being a little paranoid. Thanks again for putting me at ease.


Matt M

There is some downside to some step up transformers.

They may be susceptible to hum, due to magnetic interference.

Also turning the volume way up (without a step up) may increase the noise level.

Mattmiller,

Ive auditioned the Chinook not long ago. Using a .5mv cart, I couldn't figure out why  I had to crank the volume past 12:00 o'clock for a listenable volume, and I heard zero life coming out of the speakers.

I realized I didn't check to see if the dip switches were set for the high gain 60db setting.

Whilie I'm no audio expert, I can't imagine a  .2mv  difference making that much difference as  your preamp also provides a couple of DB's of gain as well. 

Just another thing to check before throwing in the towel and opening your wallet.

I found the Chinook to be a nice sounding unit. Quieter than my tubed Fosgate, at louder than normal listening levels-past 12:00 o'clock. The Foz however, edged out the Chinook with a more "realistic" presentation.