I'm a bit of a looper-fan, using mine with keyboards to generate improvised soundscapes - most often with just my Mellotron sounds. To this end I have a few hardware looping options, though I'm more often using software loopers these days.
The Boss RC-505 is pretty much *the* standard for vocalising loopers, and with good reason. It is simple to use (once set up to your satisfaction - though this can be quite complex at first), has physical faders and chunky 'can't miss' buttons for each channel, and also incorporates effects on both input and output, so you can add delay, reverb, etc. I have to say that this is still my favourite looper - it just does the job with the minimum of fuss. Basic drum machine built in, too, which might be all you need.
Having the five faders to hand makes for a rewarding creative experience - setting up loops, fading them in/out, overdubbing and replacing behind the scenes...
Roland have recently released an RC-505Mk2, with improved audio, expanded functionality and connectivity. I hit problems with it straight out of the box. The biggest show-stopper for me was it missing the start of overdub recordings. I also missed the lack of a simple, global 'undo'.
https://www.soundonsound.com/reviews/boss-rc-505-mkii
I went back to a Mk1.
https://www.soundonsound.com/forum/view ... hp?t=81414
The TC Helicon VoiceLive is a good option for many. This device has a simpler, 1-track looping capability (which can be a blessing and a curse), but adds multi-part harmonising, which can be sublime and acceptably convincing in many contexts. I have the VoiceLive 3 Extreme, which I use to help out vocalists who otherwise struggle with harmonies. I haven't used the looping in anger, since I find it too simplified and hidden behind too few controls.
https://www.soundonsound.com/reviews/tc ... oicelive-3
The other looper I've frequently used live is my Line 6 Helix (I also have the HX Stomp XL, but I've not used this live). Again the Helix devices feature a simplified 1-track looper, and I find this restrictive. I also use the Helix's physical switches and pedals to control other loopers (including the RC-505), since I map the same buttons to the same functions, no matter which looper (hardware, or software) I'm using. This way it hardly matters which looper I'm using - the controls and results are (*should be!) the same. The full Helix would be overkill for you, but the HX range might appeal.
https://www.soundonsound.com/reviews/line-6-hx-stomp
If you're prepared to go software that's another discussion, but my current favourites are Melda's SuperLooper and Audio Damage's Enso. SuperLooper is closest to the RC-505 (and works with my standard control layouts as if it *were* a 505), whilst Enso is simple and slick, though is again a one-track looper.
I've begun to look at iPad loopers, but getting the audio in/out is a barrier to me as yet.
Hope something here helps.
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One of the reasons I ditched the RC-505Mk2 is because I couldn't map my standard looper controls one-for-one with the Mk2.
