Best preamp for this purpose

[Oneply]

I have read through several treads and do not think I have found this addressed. If I missed it, please call it to my attention.

I sing and accompany myself on acoustic guitar. Currently I am using an Emerald Opus X 30 12-string with a b-band pickup and a CA Legacy Vintage 6-string with a Fishman Pro Pre-Blend. I have several wooden Santa Cruz guitars, a Taylor, a Martin. which do not have pickups.

I want to buy equipment that I can use for both live and studio.

The microphone forum recommended I purchase either the Shure SM7 or the EV-RE20 for vocals since they match best my vocal range. One post warned me that I needed to get a preamp with plenty of power for the Shure SM7.
What preamp would recommend for this purpose? It needs to have at least two channels (one for a microphone and one for an input from my acoustic guitar). I would prefer a four channel preamp since I hope to mike my guitars that do not have a pickup some day. But if I have to do it, I’ll wait and start with a two channel. Cost is an issue but if I have spent thousands of dollars on guitars it does not make sense to cheap out on the other necessary equipment.

For live performances, I plan on going from the preamp to a self-powered speaker(s) like the Mackie SRM450.

As always I am open to constructive criticism.

[PoorGlory]

Since you want to also use the same rig live, I suggest buying a small format mixer. I recommend picking up a used Ashly MX508 or MM508 rackmount mixer. 3 rack spaces, 8 channels, great EQ, 2 aux sends... the preamps have an enormous amount of clean gain, as this mixer was seemingly designed for applications like theatre or auditorium installations. I recently picked one up on ebay for $350 (they retail for like $1200). So far I have used it to track drums with excellent results, and I've used it to mix OTB 4 stereo subgroups from my DAW. The EQ is awesome, and the result was really better than I expected. One of the live sound companies I work for uses it as a sidecar mixer to create a tom tom submix for one band in particular, as their inputs exceed the available channels of the Crest consoles we bring out to those shows.

No one seems to be jumping on these mixers, and I can't understand why. Everyone loves Ashly EQs and compressors, but this piece is a sleeper. Pick one up now before other people start figuring out how cheap you can get them. Any price under $500 is a steal for these.

I wouldn't really recommend using an SM7 or RE20 on live vocals, although you certainly can if you want. They're just not the most "rugged" mics in the world, and I would rather have a dumbass fan/drunkard/stupid MC knock over a mic stand with a less-costly and more resilient mic on it. I often use RE20s live for trumpets and saxophones, but I frequently mix monitors so I am generally in a position to protect more expensive mics from stage mishaps. I would check out one of the Audio Technica live vocal mics for that specific purpose, as I'm not really a fan of the SM58. But feel free to get an SM7 for recording work... you won't be disappointed.

[PoorGlory]

There's an MM508 on ebay right now for $349 Buy it Now. Definately worth it.