Default EQCurves

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Revision as of 02:56, 12 October 2010 by Galeandrews (talk | contribs) (Acoustic 78 rpms were not recorded with EQ so the "acoustic" curve doesn't seem useful)
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Here is a starting point for a default list of curves. This forms part of a Proposal for Import and Export of Equalization curves. Note that I have added some attributes to the 'curve'; these are not decided on yet.

You should be able to copy-paste the curves in the box below into EQCurves.xml and have them appear next time you open 'Effect->Equalization...'.

The following curves have been suggested (only the ones marked in green are actually in the current proposed default curve.

Also see Submit your EQ Curves on the Forum for some possible curves for consideration.

  • 60 Hz notch - Gale: We are going to distribute notch.ny with Audacity which can cut a much deeper notch, so we probably don't need this. Additional parameters have been proposed for this (curve length="8192" category="default" draw="yes" log="yes") but filter length can't be set this way yet.
	<curve name="60Hz notch">
		<point f="49.4" d="0"/>
		<point f="60" d="-120"/>
		<point f="71.3" d="0"/>
  • acoustic - Gale: generic acoustic 78 rpm curve. In reality there are hundreds of 78 rpm curves.
  • MJS: Who says 'acoustic' is a 'generic acoustic 78 rpm curve'? I've never seen that before. I always wondered what it was! It looks very crude and not very useful to me.
    • Gale: Good job you queried it. I'm sure from comments I've seen before that it was "intended" as some kind of "very early" curve, but on reflection the huge cut in the lowest frequencies makes little sense. In any case from now casting around in articles on the web e.g. it's clear that acoustic 78 rpms were not recorded with any EQ; the idea only started in the electrical era. So I also think this curve isn't useful.
	<curve name="acoustic">
		<point f="50" d="-20"/>
		<point f="63" d="5"/>
		<point f="70" d="4.400000095367"/>
		<point f="100" d="3.299999952316"/>
		<point f="125" d="2.5"/>
		<point f="200" d="1.700000047684"/>
		<point f="250" d="0"/>
		<point f="2000" d="0"/>
		<point f="3000" d="-1.5"/>
		<point f="4000" d="-2.5"/>
		<point f="5000" d="-3.299999952316"/>
		<point f="6000" d="-4"/>
		<point f="7000" d="-4.5"/>
		<point f="8000" d="-5"/>
		<point f="9000" d="-10"/>
		<point f="10000" d="-15"/>
		<point f="15000" d="-20"/>
  • amradio

MJS Does this do a good job of simulating an am radio? I doubt it. I think it should be flatter in the middle (maybe 50Hz - 3.5kHz) then slope off faster above 4kHz. It certainly needs much lower points at 20Hz and 48kHz so we don't get them 'shelves'. Should it be simulating an 'am radio' or giving the impression of an 'am radio'? In a play (or whatever) a lower quality (BW) may give a better 'impression'.

We have about 4.5kHz at the top end in the UK, th US has 'only' 4kHz.

	<curve name="amradio">
		<point f="100" d="-20"/>
		<point f="125" d="-16"/>
		<point f="200" d="-12"/>
		<point f="250" d="-8"/>
		<point f="300" d="-4"/>
		<point f="400" d="0"/>
		<point f="1000" d="0"/>
		<point f="2000" d="-4"/>
		<point f="3000" d="-8"/>
		<point f="4000" d="-12"/>
		<point f="5000" d="-16"/>
		<point f="6000" d="-20"/>
  • bass boost
  Paste here
  • bass cut
  Paste here
  • Inverse RIAA Gale: This is a convenience included in 1.3.12 release, but not mandatory as you can use the button to invert the RIAA curve.
  • MJS: This is outdated by the improved RIAA curve below. I suggest that it is not included in the default EQCurves for the reason given just above.
    • Gale: Agreed it's marginal, though no doubt some would like it/may not figure you can invert the RIAA curve. I don't mind updating it against the new RIAA curve if others think we want it. If not, it can go.
	<curve name="Inverse RIAA">
		<point f="30.000000000000" d="-18.600000381470"/>
		<point f="31.000000000000" d="-18.500000000000"/>
		<point f="50.000000000000" d="-16.899999618530"/>
		<point f="63.000000000000" d="-15.899999618530"/>
		<point f="70.000000000000" d="-15.300000190735"/>
		<point f="100.000000000000" d="-13.100000381470"/>
		<point f="125.000000000000" d="-11.600000381470"/>
		<point f="200.000000000000" d="-8.199999809265"/>
		<point f="250.000000000000" d="-6.699999809265"/>
		<point f="300.000000000000" d="-5.500000000000"/>
		<point f="400.000000000000" d="-3.799999952316"/>
		<point f="500.000000000000" d="-2.599999904633"/>
		<point f="600.000000000000" d="-1.799999952316"/>
		<point f="700.000000000000" d="-1.200000047684"/>
		<point f="800.000000000000" d="-0.800000011921"/>
		<point f="900.000000000000" d="-0.300000011921"/>
		<point f="1000.000000000000" d="0.000000000000"/>
		<point f="2000.000000000000" d="2.599999904633"/>
		<point f="3000.000000000000" d="4.699999809265"/>
		<point f="4000.000000000000" d="6.599999904633"/>
		<point f="5000.000000000000" d="8.199999809265"/>
		<point f="6000.000000000000" d="9.600000381470"/>
		<point f="7000.000000000000" d="10.800000190735"/>
		<point f="8000.000000000000" d="11.899999618530"/>
		<point f="9000.000000000000" d="12.899999618530"/>
		<point f="10000.000000000000" d="13.699999809265"/>
		<point f="15000.000000000000" d="17.200000762939"/>
		<point f="16000.000000000000" d="17.700000762939"/>
  • loudness
  Paste here
  • RIAA Gale: This one is essential. MJS: Agreed, but lets get it right. This is at 1/3rd octave intervals.
	<curve name="RIAA">
		<point f="20.000" d="19.274"/>
		<point f="25.000" d="18.954"/>
		<point f="31.000" d="18.516"/>
		<point f="40.000" d="17.792"/>
		<point f="50.000" d="16.946"/>
		<point f="63.000" d="15.852"/>
		<point f="80.000" d="14.506"/>
		<point f="100.000" d="13.088"/>
		<point f="125.000" d="11.563"/>
		<point f="160.000" d="9.809"/>
		<point f="200.000" d="8.219"/>
		<point f="250.000" d="6.677"/>
		<point f="315.000" d="5.179"/>
		<point f="400.000" d="3.784"/>
		<point f="500.000" d="2.648"/>
		<point f="630.000" d="1.642"/>
		<point f="800.000" d="0.751"/>
		<point f="1000.000" d="0.000"/>
		<point f="1250.000" d="-0.744"/>
		<point f="1600.000" d="-1.643"/>
		<point f="2000.000" d="-2.589"/>
		<point f="2500.000" d="-3.700"/>
		<point f="3150.000" d="-5.038"/>
		<point f="4000.000" d="-6.605"/>
		<point f="5000.000" d="-8.210"/>
		<point f="6300.000" d="-9.980"/>
		<point f="8000.000" d="-11.894"/>
		<point f="10000.000" d="-13.734"/>
		<point f="12500.000" d="-15.609"/>
		<point f="16000.000" d="-17.708"/>
		<point f="20000.000" d="-19.620"/>
		<point f="25000.000" d="-21.542"/>
		<point f="48000.000" d="-27.187"/>

  • rumble filter
  Paste here
  • telephone - 300Hz-3kHz (should it be 3.8kHz?), 4th Order roll-offs. Done from a spreadsheet.

MJS: This needs a point adding at 48kHz

	<curve name="Telephone">
		<point f="20" d="-94.09"/>
		<point f="200" d="-14.25"/>
		<point f="250" d="-7.24"/>
		<point f="300" d="-3.01"/>
		<point f="400" d="-0.41"/>
		<point f="500" d="-0.07"/>
		<point f="1250" d="-0.004"/>
		<point f="2000" d="-0.17"/>
		<point f="2500" d="-0.91"/>
		<point f="3000" d="-3.01"/>
		<point f="4000" d="-10.41"/>
		<point f="20000" d="-65.91"/>
		<point f="25000" d="-73.67"/>
  • treble boost
  Paste here
  • treble cut
  Paste here
  • others that should be in the default list
  Paste here