If you are getting the volume you need from your existing setup, then you don't need a preamp with any gain.
The problem with controlling the volume from the DAC is that this is often done by reducing the number of bits going to the DAC, which reduces resolution. An analog volume control doesn't do this. Since you are using an external DAC with your Node 2i, the only way it can control the volume is to reduce it digitally before the DAC processes the signal.
I can recommend the Schiit Saga+ preamp. It is zero gain, and offers both a passive mode and tube buffer option. The volume is controlled by a stepped resistor network so the balance between channels is very precise. It also comes with a remote. Cost is only $400 and they have a two week trial policy but do charge a 5% restocking fee if your return it. If you need extra gain or want something fancier, the Schiit Freya+ preamp is $900. Both units are popular with lots of good reviews.
The problem with controlling the volume from the DAC is that this is often done by reducing the number of bits going to the DAC, which reduces resolution. An analog volume control doesn't do this. Since you are using an external DAC with your Node 2i, the only way it can control the volume is to reduce it digitally before the DAC processes the signal.
I can recommend the Schiit Saga+ preamp. It is zero gain, and offers both a passive mode and tube buffer option. The volume is controlled by a stepped resistor network so the balance between channels is very precise. It also comes with a remote. Cost is only $400 and they have a two week trial policy but do charge a 5% restocking fee if your return it. If you need extra gain or want something fancier, the Schiit Freya+ preamp is $900. Both units are popular with lots of good reviews.
