The Behringer ADA8000 is probably already known to most, especially in the home/project studio market, as it's by no means a new product. However since mine recently died (adat out stopped working), I have been looking at alternative products lately, and it has since crossed my mind that a perfect replacement for a Behringer ADA8000 is... a Behringer ADA8000. I couldn't find any reviews on here so I thought I'd add one, in case anyone was in the market for one and wanted the opinion of someone who has used it for about four years.
For about US$170 (new on ebay), this one rack space piece of gear offers 8 channels of mic pre, and 8 channels of AD/DA conversion at 44.1 or 48kHz. The mic pres have phantom power, but this is not individually selectable - it is either on for all 8 channels or off. On the front face of the unit, each channel has an XLR input and a TS unbalanced line input (however the line input does not bypass the circuitry of the pre amp - it is still affected by the pre's gain control).
Metering is taken care of via two lights for each channel; one to indicate there is signal present, the other to indicate the channel is clipping. Considering the size of the unit, this is a sensible approach and I haven't had any trouble with it, especially as I (like the majority of people, I'd imagine) can monitor the signal in my DAW. The adat I/O and XLR analogue outputs are located on the back of the unit, along with wordclock in, an adat/wordclock in switch, and a 44.1/48 switch for when the unit is being used as the master.
In terms of sound, the unit holds its own with the pre amps/converters in my Digi 002. The pre amps become a little noisy when boosting quiet signals, but that's par for the course at this level. The volume also jumps up radically on the last step of the gain pot, but I haven't found that to be a serious issue. I haven't used the unit with external pre amps, but the quality of the converters seems to be quite good. There is an interesting thread here on gearslutz comparing it to a Lynx Aurora converter in a shootout. Worth a look if you're interested in the ADA8000 mainly for its converters: Lynx Aurora 16 vs Behringer ADA8000
As far as reliability is concerned, after four years without a hitch, the adat out on mine stopped working. I don't want to read too much into this though, as I've had far more expensive pieces of gear stop working on me in less time.
Although the sound of this unit is far from special, it gets the job done, which is fine considering the features and the price-point. In fact when you consider its just over US$20 per channel, it's amazing that it sounds passable at all. If you're broke and need to add 8 channels to your rig, I'd say go for it. I think I'm going to. Again...