Is 57db gain enough for Dynavector XX-2?

The rated output of the Dynavector is 0.23mV, which is 2.4dB less than 0.4mV. That's how much louder the noise will be with the Dynavector. That's a relatively small amount IMO, but you may be more sensitive to tube-rush noise than I am.

You won't be taxing your preamp, but you may be taxing your tolerance for noise. Only you can judge.
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.25mV is wayyyyy to low for 57db of gain. You won't even hear much at full blast on the volume control.

Your gonna need another phonostage.

Sorry to disagree with the others, but I use a Denon DL103D with a slightly lower .24mV output. I've used a Monolithic PS-1 with 53 db of gain and that worked pretty well. Good enough to not have any real problems with noise or volume.

And, now I use that cartridge with an Acoustech PH-1 with 60 db of gain and it works GREAT.

So, I would say that you should be fine with 57 db of gain. It may not be 100% optimal, but certainly 95%. I'd say you won't have any noticable problems at all.

As with much of this stuff, it's try it to know for sure. But with my experience I'd say you'll be just fine.

Paul Green

Sorry to disagree with the others as well, but the picture that you paint in incomplete. The gain of the phono preamp must be added to the gain of the preamp to determine total gain. With a tube preamp with say 20db of gain, you will have a total of 77 db of gain, and provided that the noise floor in the phono preamp is low enough, this should do with the added gain of the amp. If your preamp is of low gain, or if your phono preamp has a high noise floor, then you are skating on the edge.