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I wonder if you have any information regarding the highest frequencies that is present in commercial LPs.
I was having a discussion with some of my audio buddies, while some of them claimed LPs do contain musical signal above 40-50kHz, others (including myself) believe the frequency response could not reach much above 20kHz. I just wonder if anyone has concrete information on that.
A couple more questions related to this topic:
1. Since many of the golden recordings were from the 60s and 70s, what are the frequency limits of mics and master tapes of that vintage? I suppose if the mics could not pick up much above 20kHz, the signal won’t be present on the LPs
2. A quick check comes up with the following frequency responses of some of today’s top cartridges:
ClearAudio Gold Finger: 20-100kHz
VDH Colibri: 5-65kHz
Lyra Titan i: 10-50kHz
Ortofon Windfeld: 10-80kHz
Denon 103R: 20-45kHz
They all claimed frequency response of way over 20kHz, but all of them didn't show any +/- db figure. Also, I am not sure how they made the measurement; from a testing LP or something else!
Actually LP is a pretty treble-unfriendly medium. Here are a number of issues to ponder:
1) Cutter HF response is not very extended. The best seems to be the (rare) Ortofon DSS731, -5dB at 30kHz. The ubiquitous Neumann SX66 and SX74 were significantly worse. (Note that quad albums were cut at
half speed, hence the apparent response beyond 30kHz.)
2) The cutting process uses treble limiters, as too hot treble can burn the cutter's coils, something not tolerated in a commercial venture.
3) Many LPs since the early 80s, and even late 70s, were cut through a digital delay line (to allow the groove spacing computer to do its job). These delays typically sampled at 44.1kHz, 48kHz, 50kHz, thus hard-limiting the result to 22kHz, 24kHz, 25kHz.
4) The manufacturing process is lossy, with stamper wear manifestating earliest as pure treble loss.
5) Upon replay tracing and tracking errors cause a level of distortion that reaches 10% (!) at 20kHz with most cartridges.
In the past years I have done spectral analyses on many commercial LPs.
Very often this reveals a hard ridge in the range 20-24kHz, indicating a digital master or digital delay line. Sad but true.
In nearly all cases was it clear that the spectral response above 20kHz was dominated by the distorion components of the baseband signal.
I have seen one (1) commercial LP that has something at 30kHz that I cannot reduce to mere distortion. It is probably a studio artefact.
However, when testing Japanese direct-cut LPs made in the 70s the spectral analysis looks much cleaner and with a nice and continuous response out to 40kHz or so. So it can be done, but it is inlikely
to happen on a mass-produced commercial product.
bring bac k dynamic range
Vinyl can go to 40k hz, especially in D2D and quad carrier frequencies. But it doesn't happen that often. Worse, the harmonics generated by the quad carrier created an artificial brightness to most of those recordings.
Another difficulty was that even Master tape decks had treble trouble, even at 30 ips. It was well into the LP era before they had that capability. In fact, liquid helium cooled lathes beat tape decks there though they did not like doing it for long periods at a stretch.
Redbook CDs cut off even lower than that.
In a true instrument (rather than a synthesizer), nothing goes anywhere near that high except the Nazard stop on a pipe organ which is only there to add "shimmer". In that instance I believe actually recording the frequency in addition to the harmonics generated is beneficial . . . but not a lot. Then again, I could hear silent dog whistles, ultra-sonic stop lights and actually hear a nazard well into my late 30s. Trust me; it is not a blessing!
At least I didn't howl at the moon.
Thanks for the very informative response, Werner. I take it that half-speed mastering, as done routinely by MFSL (and subject of much debate on this forum) is a win in this regard. Presumably it avoids the cutting head frequency limitation. (I realize it can have negative consequences at the low end, with increased interference from mechanical vibrations.)
Clearly there are great sound quality differences between pressings, between vinyls from the same pressing, etc. and this fills in more of the potential reasons for these differences. The presence of (clean) high-frequency information seems to be key to the perceived sound quality, however we manage to hear or be affected by it.
More to the point: what is the highest frequency an adult male can hear? You would be surprised how low it actually is.
Usually about 16khz in the early 20s. There are radical exceptions. I know because I was one. I could still hear beyond 24khz well into my 30s (see my response to Werner). I mention 24khz because that was the limit of the test equipment in those days.
By the time the majority of men are in their 40s 10khz to 12khz is fairly normal.
As for people who listen to incredibly loud music (even headphones) hearing decreases across the entire range but treble is even worse.
Being in my 60s now, my hearing is much more normal but still in the normal 20 year old range.
At just shy of 56, I can still hear to around 14 kHz in my right ear; I used to get up to higher than 15 kHz (I don't know how much higher, though). The sound of the high-frequency oscillators in TVs used to drive me batty! No more, alas.... My left ear, unfortunately, got hit by a disease process that destroyed the bones of the middle ear and invaded the mastoid. In that ear I don't hear below about 100 Hz, and not above about 7 kHz. I take good care of my ears these days!
If you are (were) an organist as your moniker implies, 32' (even 16') stops wide open can cause a lot of damage, as can trompettas but for a very different reason.
I am genuinely very sorry about your hearing problems. It is nasty for anyone but particularly for musicians and music lovers.
I consider myself fortunate. I don't need hearing a hearing aid yet, even for my compromised ear. I have a small pipe organ at home as a practice instrument, but it doesn't overwhelm my living room--I'm safe there! My Sunday job is on a modestly-sized pipe organ, so little danger there, either. But another instrument I have access to has just the kinds of stops you describe--I use musicians' earplugs then. I never did subject my ears to rock concerts years ago, and I'm thankful now!
The old CD-4 quadraphonic records from the 1970s used a 30KHz carrier frequency to carry the R and L difference signals. The Shibata fine line stylus profile was invented to read that carrier frequency. You can read some details of how CD-4 worked on Wikipedia at the link below.
But 29k is conspicuously low for tape deck bias.
bring bac k dynamic range
It might be a cantilever resonance.
Or flyback from a monitor.
Many older recordings contain NTSC or PAL whine. Newer ones can have
anything from 15kHz upwards, depending on the type of computer CRTs in the studio. Thank goodness for LCDs...
bring bac k dynamic range
... which he initially only noticed [i]visually[/i]. The record was profoundly iridescent.
He mentioned this in an interview a while back. Maybe with George Cardas?
Industry Update has a report pages 14-18 from the german Audiophile recording label Acousence which compares the spectrographs of a hi-rez (24/192) recording of a classical segment (Shostakovich symphony 15) with the CD master and LP transfer. The LP spectrograph was virtually identical to the Hi-Rez master with content up to 60 kHz. The CD had nothing over 22kHz as you would expect. The graphs are brutally explicit. I searched the online Stereophile site but can't find the report there.
Some quotes from the report:
"Koschnicke has experimented with DVD and SACD, but to his surprise, he finds analog LPs closest to the 24/192 digital master"
"Koschnicke has done spectral analysis of a passage from the Shostakovich that shows the digital master's high-frequency content (fig. 1) is transferred to the LP with astonishing fidelity (fig. 2) ... while the CD (fig.3) truncates the highs."
"The plot shows that the LP faithfully preserves the HF content of the 24/192 master"
I recall some of the mc carts I owned came with individual pen charts up to 60 kHz.
Read Werner's post.
You will see spectral response above 20kHz on lots of LPs, if not on the vast majority. But cutter heads would generally not go higher than 22kHz. Nobody had any interest in anything above that.
A low-impedance MC easily reproduces frequencies up to 50kHz.
On paper, vinyl and the CD alike look pretty useless. But they can sound surprisingly good.
"Ignorance more frequently begets confidence than does knowledge: it is those who know little, not those who know much, who so positively assert that this or that problem will never be solved by science."
The recording engineer at Acousence clearly heard that LP was closest to the 24/192 master, investigated the phenomenon and objectively demonstrated the reason. Admittedly the cutting and pressing process was audiophile standard (DMM, half-speed, careful plating etc) but other labels could do it if they had the will.
I can hear it too, which is why I prefer vinyl over all other formats.
I can assure to you that in my system LPs sound much better than ordinary CDs and FM tuner which seem a bit rolled off at extreme highs. In respect of the best recorded LPs, they could sound with lots of "high end air" or "rich in natural harmonics". Of course, it depends the capability/sonic behaviour of the rest of the system, particularly the tweeters of the speakers.
As far as I understand, on the other hand, "20kHz" is not the standard nor the frequency limit for the analogue masters during the golden ages. Nevertheless, LPs with digital recordings made in early 1980's don't sound very good in my system(a bit compressed, not airy enough, a tad dull...etc.)
"Frequency responses" on cartridge specifications are for reference only. It represents a cart capability in that area at its optimum loading only. It would be tricky or even misleading without "dB" or "load" information.
My advice: always trust our ears, not the specifications on its manual!
Another advantage of top-notch LP systems is: much easier to have a deep, wide, layering soundstage. In short, it's easier to have "bring you there" experience than ordinary CDs.
Finally, you may or may not hear such differences in entry level systems.
whether there is MUSICAL information there or not may be debatable. having a limit of 20k might just give you some of the problems of digital 44.1/16 recordings that lack realism.
just as you want your amplifier to have headroom above its power rating for peaks, you want your cartridge and vinyl software to have it for frequency capability so it doesnt run out of steam on peaks at the frequency extremes. you know, so it doesnt distort the instant you approach the limits.
its been said that the very high frequencies are not sensed so much by the ears but the hair follicles. that would explain the hearing acuity of julian hirsch. ;^)
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