600 bucks bring you to the Groove Tubes brick. Often used as a bass DI this unit is also nice for some Microphone PreAmping. Real tubey sound! Mhhh tasty!
For about 800 you will get a single PACIFICA Pre from A-Designs. It is very famous for it's real nice colour.
Audient Black MicPre seems to spend a lot of colour, too! Have not heard it so far (700).
For $800,00 you are the lucky owner of Shadow Hills Mono GAMA Mic Pre! Text from Vintage King Audio: Single channel vertical module version of Gama 8, fits in any API 500 series rack or console slot. 60DB gain range: reverse audio taper pot (stepped pot and St. Ives transformer options are not available as on GAMA 8), 3 transformer positions: Nickel, Discrete, Steel, Phase reverse, PAD, 1/4" DI, bakelight knobs, Illuminated display, discrete Class A/B. Runs on the 16v API power source. These are not hot swappable.
If you would wait until you can spend 1k I would recommend the the Chandler Germanium Pres! This is much colour in a really exciting way!
Also for about 1K or 1300 dollars you will get single channel pres of Great River or (and that is ma personal hero) Brent Averill! These units give you a damn sexy nevish colour. The Great River a bit more modern and the Averill a bit more vintage as far as I have heard! Okay this is nearly twice the price you wanted to pay! But worthy!
I do not know where your way goes to, but if you want a mixed system with different flavours, I would buy a rackmount for the monomodulten available today and buy defferent Pres! At first you will not come to eight channels, but in the end it will give you a real nice setup! Think about a rack with two SSLs, two Brent Averills, two Shadow Hills and two other units! Sexy!
Good luck on your search!
