...I'll start a separate thread for mixers with phantom power but if you want to comment here that's cool. Not sure if a USB versus analog output mixer is the best way to go for this setup.
Thanks
I have had to take a more modest approach in terms of equipment costs for home recording (for me it's a small hobby within a hobby). It can be done. You may not get road worthy professional quality products, but you can still get good quality products that will last in a home/hobby environment.
In my limited experience, USB outputs aren't always a clear winner. Much of it depends upon how your computer hardware (mother board, sound card, etc.) was built. Sometimes the sound card beats the USB in terms of audio quality. You have to be willing to go either route (USB or sound card) depending on the results you get with any given computer.
I have an ART Tube MP USB mic preamp (XLR, TRS, and USB outputs), and also a Behringer Xenyx 1202FX mixer (TRS and RCA outputs, no USB output). Both can supply 48 volts of phantom power.
While I like both the preamp and mixer, I should have gone the mixer route in the beginning. Better bang for the buck in terms of scalability and control. For my needs the sound and build quality of the Behringer Xenyx line has been fine. I'm still glad I have both a mixer and a separate mic preamp.
I didn't get a mixer with USB outs because, as I shared above, I've had mixed experiences with USB. Also the USB audio specs will change over time. An analog mixer itself won't get outdated.
Right now a lot of reasonably priced USB devices will only output at a maximum of either 16 bit 48 kHz, or 24 bit 48 kHz. To get higher rates costs more money (if you can find higher rates).
USB can also have latency issues if you record a lot of stuff at once. Depending on how many channels you record at once, sound cards with breakout cables or breakout boxes, or even Firewire, may be a better choice.
Getting an analog mixer without USB kept the cost of the mixer down. Because I found I had a computer with a poorly shielded sound card, I purchased an inexpensive Behringer UCA-202 USB Audio Interface (16 bit 48 kHz output max) for $30. It's audio CD quality, and the whole setup still ended up costing me less than a mixer with built in USB. When the USB technology advances I can purchase another audio interface if needed.
Most times I find USB devices output the audio signal at a lower volume than a standard analog output. With USB I've usually had to crank up the output volume from the device as it heads into the computer.
I have also found that some computer motherboards shield USB ports better than other ones. I have one computer where the USB port picks up electrical interference when adjacent USB ports are in use. When I input audio via USB on this particular computer, the recording gets a low volume high pitched hum. It ruins the recording. But on this particular computer the sound card produces outstanding quality recordings. So I input both the mic preamp and mixer (depending on which I am using) through the sound card's "Line-In" and love the results.
On another computer the sound card picks up electrical interference from things like moving the mouse. USB on this computer provides a noise free input. Go figure. If I use the mixer on this computer I pipe it into the computer using the Behringer UCA-202 USB Audio Interface. I have found this device is noise free and works well. The audio is still a bit lower in volume and the output from the mixer has to be turned up more.