• alex_vice 6 months ago

    hi guys! recently did a few vinyl rips and noticed that notorious high frequency roll-out on some records is much more noticable. i was wondering if any of you guys know how to compensate for that in digital workstations like audition/reaper/audacity? i mean, what frequencies to boost or filters to apply? perhaps there is something specific for that purposes?
    cheers!
  • King.of.Pain 6 months ago

    Try AVS audio editor, it's useful but you've got to search for your own settings by making multiple tries. It takes a bit of time to learn using but once you have it gives extreme satisfaction.
  • mjb 6 months ago

    mjb edited 6 months ago
    I ripped an old hi-fi test LP which has a pink noise track on it, then made a logarithmic frequency analysis plot of it (in Audition, Alt+Z). I compared it with the plot for generated pink noise (which makes a nice straight, diagonal line).

    After adjusting the overall volume level to match as much as possible, I noted where the peaks, dips, and rolloffs were (in Audition you can freeze more than one plot on the same graph, so it's easy to compare them), e.g. noting that at 1600 Hz it was a perfect match, at 2650 it was 1.8 dB too high, and so on. I used this with to come up with an FFT-based EQ curve to flatten the rip's plot into the same straight, diagonal line as the generated plot. This of course assumes that the test record was manufactured without any aberrations in frequency response...I'd like to think they tested it and made sure everything was correct.

    The results of applying my flattening EQ seems to provide good results, although naturally it does take away much of the "character" of the cartridge. Interestingly, my cart (VM740ML) needs a bass boost and a mid-and-treble cut, generally speaking.

    Another method is the same process, but using a snippet of an early '90s dance track which I have on both 12" and CD. This is a bit riskier since the two formats can be mastered with very different EQ, and because unlike pink noise, the frequency plot is not going to be a straight line. But I used this method to check the results of the pink noise-based EQ setting, and it indeed made the vinyl sound just like the CD, to the extent that my ears can hear, so I'm satisfied.

    All that said, getting flat response is not necessarily going to address the question! The rolloff mastered onto the vinyl is often intentional, a side effect of what's needed to keep the cutting head from overheating, and to reduce "inner groove" distortion caused by the lack of space near the center of an LP for the tiniest wiggles of the groove. That varies from mastering to mastering. Sometimes there's not much change at all, and sometimes there's a sudden dip in treble response (when the engineer manually made an adjustment), and sometimes it's a very gradual rolloff.

    In one instance, I noticed that the end of one side of a 12" was quite a bit duller than the beginning, so I did a crossfade trick: First I EQ'd the whole side to make the end have the same treble as the un-EQ'd beginning. This of course made the beginning way too bright. The next thing to do is a linear fade in, so the beginning is silent and the end is at full volume, and then copy that audio. Now undo the fade & EQ (ctrl+Z a couple times) to get back to the original, then do a linear fade-out (so the beginning is full volume and the end is silent). Finally, mix-paste the copied audio 100%/100% on top of the faded audio. The result should be a gentle adjustment of the EQ from the beginning to the end of the side. (I try not to overthink the phase problems this might introduce.)

    The trick is figuring out where, on a given side, the treble actually starts rolling off. On that one example 12", it seemed to be a gentle adjustment across the entire side. But if the rolloff starts like halfway through the side, then of course I'd want to only apply the fade trick to the affected section.
  • kurts.ear.candy 6 months ago

    mjb

    A) That is simply brilliant !

    B) I am so glad i don't have this problem.
  • alex_vice 6 months ago

    alex_vice edited 6 months ago
    hi guys! thx for the answers!
    mjb
    I ripped an old hi-fi test LP which has a pink noise track on it, then made a logarithmic frequency analysis plot of it (in Audition, Alt+Z). I compared it with the plot for generated pink noise (which makes a nice straight, diagonal line

    its an interesting thought on using white noise as a reference. tho i dont have a white noise vinyl, still, its good to learn something new.
    mjb
    IAnother method is the same process, but using a snippet of an early '90s dance track which I have on both 12" and CD. This is a bit riskier since the two formats can be mastered with very different EQ, and because unlike pink noise, the frequency plot is not going to be a straight line. But I used this method to check the results of the pink noise-based EQ setting, and it indeed made the vinyl sound just like the CD, to the extent that my ears can hear, so I'm satisfied.

    in my case its not possible, as there is no digital release. if i had it in digital, i wouldnt care for the vinyl rip)) but, the begining of the track sounds so clean and crispy, that i wouldnt desire more, if only the track was flat all the way through, which it isnt. i guess ill try using that first quarter of the record as a reference and i suppose it all comes down to doing it by ear, more or less. tho visual reference is going to come in handy ofc.
    mjb
    All that said, getting flat response is not necessarily going to address the question! The rolloff mastered onto the vinyl is often intentional, a side effect of what's needed to keep the cutting head from overheating, and to reduce "inner groove" distortion caused by the lack of space near the center of an LP for the tiniest wiggles of the groove. That varies from mastering to mastering. Sometimes there's not much change at all, and sometimes there's a sudden dip in treble response (when the engineer manually made an adjustment), and sometimes it's a very gradual rolloff.

    a funky house tune from 2004 https://youtu.be/1TKaQJM6ZE4 an id say its golden age of that style and its manifestation on vinyl, as digital labels and stores were still in their infancy. now, 7.5 minute track recorded solely on side on 33rpm speed? looking at the grooves i can say the width between them is nearing .5 millemeter, there is plenty of space. yet, the decay of hf becomes audible from the second quarter the track. i doubt that its intentional, my best bet is that sound engineer must have overlooked that nuance, as other vinyls i have from that era and genre also do have that roll-out effect, but nowhere near as bad as this one here. sad. the track has that defining sound to 00's era, yet hasnt been oveplayed.
    anyway, thx for such a thorough answer!

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