best preamp under 500 for cheap, poor student

here are the latest specs of my dorm system (keeps changing!...I keep getting stuff from my dad's house!)

Source Technics DVD 1 10
Amp1 Electrocompaniet aw100
amp surround: marantz pm17sa
amp center nOrh Le Amp (with EVS goldmund attenuator)

Speakers: JM Labs Mezzo Utopia
Spekers surround: Home made (JM Labs, PHL and Philips) 92dB
Center : KEF Reference

I am doing most of the volume control with the dvd audio player's in-built processor. I have posted about thirty five thousand posts asking what's wrong with this and NO ONE seems to answer that question.

so if that's not the way one controls the volume suggest a sub$500 alternative ss or tube to control my electrocompaniet aw100
Also a good buy in used preamp is the B&K Pro10MC Sonata. It goes for $300 or less on the net. It is a MOSFET design for tubelike sound and has a good phono section that is internal switch for MC or MM.

I bought mine new in 1992 and am still using it.
You may be able to get the Apt pre-amp under 500, but worth it if you pay more. Mitsubishi DA-P20 underappreciated and should fit your budget.