So I was given a free pair of (what seem to look old) ADM 1540 equalizers today and I'm very unfamiliar with the product. I am not finding much info online. The ones I'm seeing online have the actual number "1540" engraved next to "ADM" but mine do not. I attached a photo. Any info on worth or the year it was made would be great. I've attached a photo.

Hello, I know from searching the site that this question was addressed by a couple of people in 2002 but, in case anyone has had more recent experience, has anyone tried this mic preamp / eq combo from ADM? If so, what are your thoughts on the units? They're going quite cheap in some places and I was wondering if anyone recommends them... Thanks!

Ethan