Mixing above 16kHz... when you can't hear it!

[ultraGentle]

This is related a recent forum post, but different enough that I didn't want to hijack that thread.

Given normal age-related hearing loss, how do you make mix decisions above, say, 16kHz?

I don't really have a concept of what information is captured in that register, or how things might compete.

If I were to EQed it out completely, would the music sound airless to people who hear that register?

If I had to prioritize instrumental or vocal material occupying that range, how might I decide?

I'm guessing this is primarily connected to transients, sibilance, maybe some percussion?

Basically, I'd like to understand how people make decisions about registers outside of their hearing.

[Hugh Robjohns]

Experience and pragmatism, mostly. Combined with careful referencing.

That said, I had the misfortune a while ago to be in a pro studio in London auditioning some new equipment. One of the music tracks being played was a classic Elton John track which sounded quite superb -- to my ears. However, a very experienced and award-winning senior engineer hosting the session there complained about the mix quality. He disappeared to retrieve a different, remastered version of the same track for us to hear, and when he played it, it had an obviously -- to most of us -- over-exaggerated top end. I found the mix unpleasantly bright and brash, and not just in comparison to the other mix, but in absolute terms, yet our senior host was raving about how good it was...

You can draw your own conclusions.

H

[Sam Spoons]

A close friend and, briefly, business partner succumbed to cancer in his mid 40's (some 20 years ago now). The chemo treatment he received caused a serious loss of HF hearing. At the time he ran a small professional jazz recording studio alongside his main job and, while he continued to work after his chemo, he made use of his son's undamaged ears to check his mixes. So, in addition to Hugh's advice, if you can make use of people around you (especially younger ones) that can be another avenue to explore.

[ultraGentle]

Hugh, I appreciate the broad strokes, but when you say pragmatism, pragmatism to accomplish what?

And when you say referencing, on a practical level how do you reference against material you can't hear? (Asked in good faith.)

[RichardT]

Interesting question. I mix based on the frequencies I can hear if I’m honest. But I do quite often use a spectrum analyser to see what is going on at very high frequencies. Some synths generate a lot of extremely high frequency content, often even > 20kHz so I will sometimes cut them above 15kHz. I will never boost above 16kHz though as I don’t know what effect it will be having (except when I use a high shelf).

Plus my mastering engineer is a little younger than me! He does sometimes treat very high frequencies during mastering.

[The Elf]

I find that as long as you don't go adding silly amounts of boost (especially at tight Qs) in the HFs they pretty much take care of themselves. I'll sometime tone them down on certain sources (fizzy distorted guitars are the most frequent culprit), but other than that you can mostly ignore them.

[Hugh Robjohns]

Hugh, I appreciate the broad strokes, but when you say pragmatism, pragmatism to accomplish what?

Pragmatism as in not trying to process things you can't hear -- leave the extreme HF alone, in the same way as leaving the extreme LF alone when working with small monitors. Or if you do feel a need to tweak, keep the adjustments mild and broad, rather than larhe and narrow!

Pragmatism as in asking the opinions of others whose views are trusted.

Pragmatism as in using visual aids to provide extra and reliable information about the extreme HF, such as spectrum analysers and/or spectrogram displays -- the latter often being the most useful.

And when you say referencing, on a practical level how do you reference against material you can't hear?

If your mix has roughly the same spectral/tonal balance -- aurally and visually -- as a commercial mix you trust, you're on the right lines... Even if both mixes sound less bright than you imagine they should be. On the other hand, if your mix sounds brighter Than the commercial mix there may be something amiss.

Age-related hearing loss is usually progressive and slow, and so most of us learn to compensate naturally and resonably well over time without even realising it. Obviously it's much harder to re-acclimatise and re-learn if the loss is sudden, such as due to chemo, or antibiotics (a friend of mine lost is HF hearing in both ears within days after being prescribed an antibiotic for something unrelated to his ears!).

[n o i s e f l e ur]

I think this might have been prompted by my comment in another thread?

I agree with The Elf here, it takes care of itself. I only boost above 15KHz just enough to register the presence of these frequencies in my reference tracks in the monitor feed . . . and no more.

It mostly restores overtones, definition and a little bit of life / air that had been missing. It was absolutely key to reference commercial (matter of opinion) material to achieve this.

And to be clear, it's an ad hoc solution - post-pandemic there's a visit to an audiologist in the cards to get a true picture of where my hearing lies - and an audiogram to correct any deficit. My point in the other thread was the calibration on the phones made my ad hoc temporary solution quite viable as it was no longer complicated by an untrustworthy playback system.

[ultraGentle]

Sam, thanks for your story -- I hadn't thought of asking my youngers-and-betters, and I shall do so.

Hugh, to your point about learning to compensate over time: my issue is that I'm beginning to learn at a point when I already don't have access to that band, so I have no experiential reference -- although I do remember quite clearly how music sounded differently in youth. Also, thanks for the elaboration.

Thanks, all, for the replies. Makes sense -- just wanted other people's cents. (After all, if you collect enough sense, you have a dollar...)

EDIT: Yes, this was prompted by the other hearing-loss related thread, though this one is about the chronic scenario, not the acute one.

[James Perrett]

The Elf's advice is sensible - take care of the frequencies that you can hear and don't do anything drastic higher up. From the amount of 15kHz monitor whine that is present in 80's recordings it is obvious that there were plenty of successful studio engineers/producers who didn't have good HF hearing at the time. In my younger days I could plainly hear it from vinyl records whereas nowadays I only know that it is there from a spectrum analyser plug-in.

[n o i s e f l e ur]

Ahhh - sorry ultraGentle - I haven't commented in the actual hearing-loss thread, but I did mention correcting for my own age-related deficit in a different one.

Great question and good (gratifiying even!) answers though.

[Tim Gillett]

"equal loudness curves" are interesting.
https://www.sfu.ca/sonic-studio-webdav/ ... is%20range.

Specifications for audio gear might quote a figure of 20 Hz to 20 Khz +- 1db. Human hearing is not like that. We're most sensitive to 3-4 kHz and our sensitivity drops off for frequencies above and below that. 15 kHz seems generally about 20 db lower and the curves I've seen dont even show data above about 15 kHz.

When I was in high school our science text stated human hearing limits as 16 - 16 khz. Later it seemed the figures had shifted to 20 -20 kHz. (we had lost some bass but gained some high end!) I tend to view 20 kHz as an absolute upper limit of audibility for young females with excellent undamaged hearing under ideal conditions.

My first YT upload 9 years ago was a soundtrack recording off TV and due to some crosstalk from video circuit crosstalk a 15 kHz tone was also recorded. The tone is even there in the YT upload. Around 65,000 viewers have listened to it. No one so far has mentioned the tone.

Due to age and probably too much band gigging I cant now hear anything above 10 kHz. With recording, the Spectrum Analyzer is comes in useful.

[Martin Walker]

Fascinating discussion, with lots of useful advice!

The only thing I can think of to add is to elaborate a little on the high-end percussion - mostly older folk will be OK mixing acoustic sounds that have been recorded (as their high end is mostly predictable), but do watch out for electronically generated ones.

Some software drum machines can (for instance) generate hi-hat-style sounds with an incredibly over the top high end all the way up to 20kHz and beyond, and in extreme cases electronic percussion sounds may be generated that are totally inaudible to older ears.

In such cases, once again you have to resort to occasional checks with your spectrum analyser, to compare what's up high with other commercial references - if you spot any rhythmic activity above 10kHz that doesn't seem to correspond with what you're hearing, solo it, and if you still can't hear anything, a gentle roll-off starting at 10kHz on that instrument can be sensible.

Martin

[James Perrett]

I tend to view 20 kHz as an absolute upper limit of audibility for young females with excellent undamaged hearing under ideal conditions.

As a teenager I could easily hear the 19kHz pilot tone from a mono FM radio tuned to a stereo broadcast - especially from the old Blaupunkt radio with electrostatic tweeters either side. In fact I could probably hear slightly higher as I remember doing a gig at a club where they must have had an ultrasonic movement alarm in the foyer and feeling distinctly uncomfortable passing it. The tone that I was hearing seemed higher than 19kHz.

[n o i s e f l e ur]

Oddly, even though my hearing seems compromised at high frequencies - it appears I can detect bats.

Doesn't manifest itself as what I'd normally descibe as high-pitched sound, it's more like a physical fluttering in my inner-ear.

So how weird is that?

[Yearofthegoat]

@noisefleur Not weird at all! I do bat surveys as part of my paid work and while I can't hear them as well as I used to, that fluttery feeling is still there for certain species.

[n o i s e f l e ur]

Well well well! There might be hope for me yet . . . Thanks for posting that, it's both interesting information generally and somewhat of a relief to hear I'm not going mad or just imagining the phenomenon.

It's possible my high-freq deficit isn't as chronically poor as I thought - as I periodically suffer from glued up ears due to congestion / sinuses - hence the decision to visit an audiologist when circumstances permit to get an accurate reading of where things stand.

I certainly still seem to be able to indentify a too-bright mix most of the time.

Franky, I'm astounded I have half-decent hearing or indeed any at all after some of the absolutely insane abuse I've put my poor ears through at live gigs. When I say absolutely insane . . . I'm not kidding.

Head in the stacks @ JAMC, MBV, Mercury Rev and many more extremely noisy and occasionally illegally loud bands. Lets just say your inner-ear makes some very interesting noises of its own when subjected to SPLs at that level. I've since got a modicum of sense about such foolhardy behaviour, thankfully.

[ultraGentle]

I'm glad this has sparked some discussion!

I think one of the reasons I asked is that I remember being affected by the upper upper register when I was kid. [Edit: positively affected!]

In my memory, I link it to the sound of string of instruments on some well-recorded classical CDs -- though I don't know if that's true, since I wasn't paying attention to frequencies at the time.

Now that I can't hear it anymore, I still don't want to treat it arbitrarily, even though it probably only matters to a few.

Good points about intuition with respect to acoustic vs. electronic instruments!

[James Perrett]

Yes, it was easy to tell whether strings were live or recorded in the analogue days by listening for the high frequencies. The same went for cymbals. It became harder to tell the difference with digital recording but you needed an extremely high quality system for the differences to disappear.