older LPs - different EQ?


After seeing 35,000+ LPs in one place on Sunday, including a wide variety of selections from the early years of recorded music, I suddenly remembered a foggy thing that I read a while back, and I want to confirm.

My impression is that pre-1958 or so (1955?) the record companies used a different equalization curve than the now-ubiquitous RIAA equalization. Is this true? If so, what sort of phono stages do equalization for these properly? Anything else to be aware of in this space?
blw
There are some different eq. curves in the older records. Columbia, Decca/London, another one that I can't remember, and the current RIAA. And yes there are some phono stages that have selectable curves that are built-in. Don't ask me to name one, but I know they are out there, because I have read about them.
My Marantz 7T (as did the original tube 7) had three different EQ curves on it, one if I remember well was a Columbia curve and also a different curve for '78s.

Bob P.
I know of one phono preamp that has adjustable RIAA curves, it is the FM Acoustics Resolution Series 122. I had a chance to listen to it about 2 years ago and it was one of the best I have heard tube or ss. I am not sure if they currently have a US importer but if you have a large collection of older lps it would deserve a serious audition.
The Krell KPA phono pre-amp also offered on-the-fly RIAA curve adjustment.

Greg D
KAB electroacoustics makes an audiophile grade remastering phono preamp. It covers every equalization curve ever used:

http://www.kabusa.com/index_pp.htm

I am getting into older LPs, especially Argentinian music!