Behringer RX1602 V2

This product works AMAZINGLY for it's price, it sounds pretty great, and is pretty flexible, you get to connect everything to it in either mono or stereo, get individual controls over 8 different channels, and global visual feedback (not per individual channel).
I do get a bit of hissing on high volumes, but I can't tell if it comes from the RX, my synths, cables or interface.

Overall I'm really happy with it, and it was a great way to get all of my synths and more into the instrument jack of my interface for dirt cheap!!

Highly recommended if you need to get many channels into one output without breaking the bank! :)

The mixer fits conveniently into 1U of 19" rack space, making it ideal to sit alongside MIDI sound modules, effects units or other outboard equipment.
Each of the 8 stereo inputs has a pair of 6.35mm jack sockets, which are balanced (trs) but can be used unbalanced if required. Switchable sensitivity makes each pair of inputs suitable for line level or microphone input.
On the front panel, each stereo channel has volume and balance controls plus a feed for monitoring or to feed an effects unit. Each channel can be individually muted, making it easy to switch off any unused channels to reduce unwanted noise.
It's easy to see which channels are muted as the muting switch is illuminated with a red led when the channel is off.
Overall master level controls are provided for left and right channels, with led bar graphs to show signal presence and levels.
The mains lead plugs directly into the back of the unit, no separate external power supply is required.
Overall, a very useful and versatile mixer that is ideal in a situation where a number of items of equipment need to be connected and have their levels set but then largely left alone.