I downloaded these curves below and was wondering are they designed to make a song sound old?
"EQ Curves for old recordings
The 1.2 version of Audacity had a number of EQ curves for electrical 78 rpm discs and early pre-RIAA LP’s which are not offered in current Audacity. If you need these curves again, download > Missing features - Audacity Support > and save it to the folder location described above. Note that the RIAA and Inverse RIAA curves in this file are now deprecated.
More advanced users can visit 78rpm playback curves for a table of “bass turnover” and “rolloff” values for a much wider range of 78 rpm discs and other early LP’s. EQ Curves for Audacity can be generated from those values using the instructions on that page."
If this is a feature request, what is the exact request?
Not exactly. They are used for correct playback of a recording made from a shellac disc where the recording was made “flat” without any correction of equalisation.
The curves can also be used to correct recordings of shellac discs where the recording equipment was modern and applied RIAA playback equalisation. In that case, the inverse of the RIAA curve would be applied and then the appropriate 78 RPM EQ curve applied.
Professional transfers of shellac discs might well be done using hardware equalisers that used the appropriate playback equalisation for the disc, in which case there would be no need to apply an EQ curve afterwards.
If you want to add analogue “warmth” or vinyl/shellac noise then you need a vinyl/shellac distortion effect. Of course if you are trying to simulate a shellac disc or a cylinder you may want to apply a treble reduction and/or bass adjustment as well, but some disc simulation effects will include some kind of EQ control (or “Year” control that may affect EQ).
Gale
"EQ Curves for old recordings
The 1.2 version of Audacity had a number of EQ curves for electrical 78 rpm discs and early pre-RIAA LP’s which are not offered in current Audacity. If you need these curves again, download > Missing features - Audacity Support > and save it to the folder location described above. Note that the RIAA and Inverse RIAA curves in this file are now deprecated.
More advanced users can visit 78rpm playback curves for a table of “bass turnover” and “rolloff” values for a much wider range of 78 rpm discs and other early LP’s. EQ Curves for Audacity can be generated from those values using the instructions on that page."
Thanks Gale… Well I didn’t really read the ins and outs of what to post–just the top/main categories 
--and try to get as close as possible (will try harder!–read more–I know). BUT coincidentally–since the EQ curves are NOT what I thought–then requesting --here now [X]. EQ curves that make a song sound as though it was recorded in the twenties or thirties. It’s funny because I remember when Audacity had those ‘78 records’ curves default in the EQ presets and they never seemed to do what I thought they would–now it’s clear. -again thanks.
So you want recordings to sound as if you heard them in the 20’s or 30’s, without the noise that would have inevitably been in such recordings?
There are too many imponderables here. What EQ was used to record the song that you want to send back to the 20’s? Is it a song recorded in this century?
What specific piece of vintage equipment do you want to reproduce? What make and model of radio, or what make of shellac record? There are dozens of 78 RPM EQ’s differing from one record label to another.
Can you post a link to a song that sounds to you as you want other songs to sound? I think you are probably asking for a treble cut and the other frequencies depend on exactly what you are trying to achieve.
If you are asking for a feature to change a song’s EQ to match the EQ of another song, that is a popular request. It can be done after a fashion in a multi-step way.
Gale
Okay–This is a pivotal song in music history and it has the 1930’s sound–because it was recorded in 1936[!]. I like the sound of the old records like this–not sure why. BUT I found (only) one plugin (iZotope) that took the challenge of creating a tool to re-create these old record’s sound–AND I did not like their results–They were also focusing on the scratches/warps etc. (damage). Which is not what I wanted. I wanted an old record sound, not an old damaged record sound—(Assuming the sound I like is not due to damage).
Oh here’s the song–ALSO any of Robert Johnsons’ really. Terraplane Blues: http://music.xbox.com/Track/67AEAD07-0100-11DB-89CA-0019B92A3933?action=play
That’s what I thought. You want the “record as played on an acoustic player” sound. The Victrola sound.
You can get that with Effect > Equalization. As a first pass, open the song and apply Effect: Equalization: Telephone curve. It’s low pitched sounds on the left and high pitched sounds on the right. Push the curve around as needed.
We do warn people that Audacity can’t act. We can simulate the sound of the performance but we can’t do the Cajun accent or the off-tune, water-logged guitar. You have to come to the table with that.
This regularly kills people in the “Make Me Sound Like” group. A lot of performance is acting. There is no “act like an announcer” or “Cajun singer” button.
Koz
If you’re not up to adjusting the curve, switch Equalization to Graphic EQ and that will give you sliders to push around.
Koz