Here we have an Electro-Harmonix 12AY7 mic preamp. These preamps are discontinued and kind of hard to find. They're a great way to get some warmth and grit on a lot of sources. I mainly used mine to track vocals, and I imagine they could be a great way to get some live vocal overdrive going without effects or abusive your mic too bad. Sounds good when I use it on a drum overhead mic, too.

The stock tubes have been replaced with a vintage Hammond 12au7 and a Groove tubes 12ay7. You can get some really creamy clean tones with minimal drive and you can also drive it beautifully with a really soft breakup that's a bit darker than you'd find with the stock tubes.

It has an XLR input, and a 1/4 and XLR output. One criticism that people have of these pedals is that they are not as quiet as more high end tube preamps. The XLR output has some hum for sure, but the 1/4 one is pretty quiet. It comes with the power supply, too.