Ultimately your ears are the best judge.
Quote from: botface on 05 March, 2012, 04:15:58 AMUltimately your ears are the best judge.That's exactly what I'm finding. Guide my thinking here.... In understanding the RIAA inverting, is it true that every device that I can use today to capture vinyl will have RIAA equalization built into it and therefore will have to have those values inverted? Or is it that the devices are the same as before but the old recordings were mastered with a certain EQ (specifically 78s)?And finally, what is being lost by not inverting the RIAA curve? I don't seem to understand that. The 78s I capture sound better without it inverted. Unless my ear is wrong which is totally possible.
Check this out though: http://wiki.audacityteam.org/wiki/78rpm_playback_curves Theres a shitload of de-emphasis curves for 78rpm's.
Just so you know, there are more than a few phono preamps for 78s on the market. Some will provide just about every, if not every, EQ ever used on commercial pressings, some are limited to just the most common EQs.
Quote from: markanini on 03 March, 2012, 03:10:02 PMCheck this out though: http://wiki.audacityteam.org/wiki/78rpm_playback_curves Theres a shitload of de-emphasis curves for 78rpm's.I have no idea how to take the values of these curves and plot them on a graph to create my own curves to apply to a recording. Can anyone help?
Except the oldest, the 78's had some EQ applied and should have some EQ applied upon playback. That EQ is not the RIAA curve, but the RIAA curve may very well (for all that I know) be better than nothing.
Not many people have suitable preamplifiers: it is possible to transfer 78s using the usual RIAA equalization for LPs and then convert. Equalizer by Brian Davies is free and will convert RIAA or flat (unequalized) to a number of other equalizations. If you have transferred a 78 at a lower speed and then speeded it up in an audio editor it will also adjust the equalization to suit. Prior to this being available I worked out some figures, and I have left them posted here in case anyone wants to experiment with them.
You can't just remove the RIAA curve and leave it at that. You'll be worse than you started.
I'm doing some Capitol 78s from the 40's. What curve do I apply for those?
So, I'd start with RIAA and adjust by-ear from there. (I know some people don't like to mess with the original sound, but I sometimes add a little high-end to older dull-sounding LPs, because it sounds better to me than the "correct" RIAA equalization.)
You should of course keep the original file (both before and after 'cleaning up' ... the 'before' in case you screw up something during the process)
Quote from: 2Bdecided on 07 March, 2012, 05:26:35 AMYou can't just remove the RIAA curve and leave it at that. You'll be worse than you started.Ok, and I'm reading about the curves but, for example, I'm doing some Capitol 78s from the 40's. What curve do I apply for those? I have a list of tons of curves but I don't understand how to plot those figures onto a chart to save that curve?
78s: WESTREX (English Western Electric) for HMV 78s with triangle matrix code and English Columbias with a (w) matrix code. BLUMLEIN for HMVs with a square by the matrix number, and English Columbias with a ©, or in both cases with no code (post 1945) up to about 1953. BSI 78 for all post 1953 78s (in theory). HMVs with a diamond are American Victor recordings: use WESTREX.
a) trying to replicate what a completely analog phonograph horn sounds like is pointless.
You should of course keep the original file (both before and after 'cleaning up' ... the 'before' in case you screw up something during the process),
"I'm going to post this link for the third time. If you don't follow it this time, I'm giving up!""You've already been pointed to this..."
It's a bit to me like when a classic film is released with a new (and ridiculous) 5.1 mix when there was only ever center channel mono in the theaters of the time.
Quote from: 2Bdecided on 08 March, 2012, 05:23:00 AM"I'm going to post this link for the third time. If you don't follow it this time, I'm giving up!""You've already been pointed to this..."I see, 2bdecided... you're one of those guys who thinks that people who don't understand things are such a nuisance that you have to point it out to them publicly. Go ahead, give up. If you bothered to read anything I've said, I've made it pretty clear several times that I am looking for something that helps me understand how I would translate the numbers you keep throwing at me into usable curves that I can program myself into an audio editing program. You can throw all the charts and explanations about RIAA you want at me and remind me what I've already been pointed to but it doesn't explain in any way how to turn them into curves for labels that aren't listed. All those specs mean nothing to me if I don't know how to plot them. Does that make sense to you? Do you get what I'm not understanding? Spare me the hollier-than-thou nonsense about how inconvenienced you are by having to repeat yourself when you're not even reading what my questions are. You gave me some useful info but spare me the other crap.
Why would you need to program these curves into audacity (or any other audio editor) when the software I linked to applies them for you and saves the output as a new wav file?
I've got Capitol, Pathe, Odeon, 4 kinds of Columbia, Okeh and severael more that don't appear anywhere in that software. Yes, I did actually install it. What do I do about those? How do I begin to know which one to choose.
% riaa2.m - plot amplitude against frequency of RIAA filterf1=50; % lower bass turnover / "low frequency" (if none use 1)f2=500; % bass turnover / "middle frequency"f3=2121; % treble turnover / "high frequency"f=1:20000; % set up array with frequencies 1-20k to calculate response at each frequency% calculate responsea=(1+i.*f./f2)./((1+i.*f./f1).*(1+i.*f./f3));a=a./abs(a(1000));% uncomment this line to calculate inverse curve...%a=1./a;% plot amplitude of result in dB (using 20*log10) on log frequency scale (using semilogx) from 20-20kHzsemilogx(f,20*log10(abs(a)))xlabel('frequency / Hz')ylabel('amplitude / dB')axis([20 20000 -30 30])