I always use the Monitor output and the Direct output for my own monitor sound. For this I use 2 jack cables with a tip and a sleeve, like for my guitar and they are plugged in into my small 8 channel Soundcraft mixer. Also my XLR mike is plugged in…

In Kingfisher Cecilia uses a condenser on her fiddle but combines it with effects pedals. This is a bit awkward to get working, and we've been using a Soundcraft Notepad mini-mixer. Unfortunately we had some issues recently where adjusting the input gain would make horrible scratchy noises: I thought I'd need to take the mixer apart to clean it, but a bit of looking online turned up suggesti

Small-format Analog Mixing Console with USB I/O and Lexicon Effects

According to various online posts, the Soundcraft Notepad line of mixers tends to develop various faults of the USB audio inteface after a few years, including constant noise. Fortunately, if you can live without the digital parts of the mixer, there's a workaround.