Super Tweeters
A few years back I was in touch with a gentleman from La Jolla, California that was nuts about his super tweeters. Although we never managed to get together for a demonstration, he insisted that his listening was transformed by simply adding a couple of super tweeters to his playback system. In light of the fact that my revered B&W 801 Series III speakers do not deliver the ultrasonic frequencies that I discuss so often in these posts, it might be interesting to acquire a set of super tweeters and put them to the test.
According to Wikipedia, “a super tweeter is a speaker driver intended to produce ultra high frequencies in a multi-driver loudspeaker system. Its purpose is to recreate a more realistic sound field, often characterized as ‘airiness’.”
This is a fair enough definition. But there is an aspect of “super tweeters” that isn’t discussed on any of the sites that I referenced during my limited research. Just what source media and components upstream from the speakers are producing the “ultra high frequencies”? They certainly aren’t coming from a piece of vinyl or a compact disc. Those few audiophiles that have a very good analog tape machine and some great master tapes might be able to get additional “airiness” out of their systems but in general the need for a super tweeter has been minimal…until now.
I found it very interesting that the Wiki article also included the following:
“A super tweeter is generally intended to respond well into ultrasonic frequencies over 20 kHz, the commonly accepted upper frequency limit of human hearing. Super tweeters have been designed…for extended-range digital audio such as Super Audio CD intended for audiophiles…”
I can pretty much guess that a DSD fan contributed to this Wiki article. That’s probably why there is a warning at the top of the page that warns that the information needs some additional citations and that the information is unverified. An SACD using standard DSD 64 encoding is the one “high-resolution audio” format that wouldn’t benefit from using super tweeters…unless you wanted to deliver all of the ultra high frequency noise to them and risk blowing them up!
Where a super tweeter would be of benefit is in a room like mine. The B&Ws do a spectacular job of delivering the “traditional audio band” to the sweet spot of my mixing room. But my DVD-Audio or Blu-ray discs contain ultrasonics across the entire next octave of the spectrum and if I want to have any chance of reproducing them in my room, I have only two choices…well maybe three.
I could go out and get a new set of speakers with extended frequency response (like the Harmon studio reference monitors that I heard recently), listen exclusively through the new Oppo Headphones (which include the additional octave) or add a set of high quality super tweeters to my setup. Clearly, the most cost effective way to proceed would be to augment my current setup with 5 super tweeters.
I can’t say that I know much about they would be mounted (phase and directional dispersion will be critical), how they might be powered or even wired up. But as “ultra high frequencies” become recognized as a necessary part of a great listening system, super tweeters might start getting another look by audiophiles everywhere.
You want to reconfigure the entire recording and replay chain to include sound you can’t hear (the clue is in the word ultra-sonic) because you think it might somehow improve the sound that you can hear. Hmmmm. To quote from the Flanders and Swann song, High Fidelity:
The ear can’t hear as high as that.
Still, I ought to please any passing bat
I’m trying to enhance the listening experience of music by making sure that the business includes all of the capabilities of current recording and distribution methods…and this includes the extension of frequency deliver to around 40 kHz. There is no doubt that there is are meaningful frequencies beyond 20 kHz and it has not been determined whether they impact our experience. It’s called fidelity for a reason. If that frequency is coming out of an instrument and is in the room, then why not record it and reproduce it? I’m not alone in believing that ultrasonic frequencies matter.
Dear Mark,
Not sure if this is known/it may help some way, but it can’t make any harm to any reader… it was published some years ago.
http://jn.physiology.org/content/83/6/3548.long
and this, http://www.cco.caltech.edu/~boyk/spectra/spectra.htm
Thanks…it spite of being 10 years of more out of date, they make a very compelling case.
You are saying Oohashi is compelling? You are going out on a limb here. A paranormal limb. A third eye.
Pleeease, don’t go there.
Here is my case for capture and playback up to 40 kHz: to be confident that we have got it really right all the way out to 20 kHz.
Microphones and tweeters often struggle at 20 kHz, in response, dispersion, phase and power handling. If we get them working well at 40 kHz then they will be cruising at 20 kHz. There may be practical benefits from this.
Grant, I’m not willing to rule out the possibility that ultrasonics might have some role to play. There are lots of microphones and speakers that can handle frequencies above 20 kHz.
Not at all, Mark: it is a pleasure to share info with you and your readers, almost as good as reading your daily post.
Now to get the balance (of frequencies) right, another anecdote but this time about the opposite: infra-sonic frequencies and its possible effects… a ghost-story http://www.skepdic.com/infrasound.html
It is very important to underline that there are no mysteries here: everything has an explanation.
Please, keep these kind of posts up. True Hi-End Audio needs professionals with a highly technical solid background and their ability to transmit (this is the key) their huge knowledge in an understandable way to move forward… or we will be lost in an eternal (commercial) “circle-of-devil”… if you could post yours also in that FB page (AIX Records, or iTRAX? – a bit messy sometimes with 2 names when looking for your posts-), it would be easier to spread your words. Just a suggestion! . Thanks!
Thanks Jorge. I do occasionally post in the AIX Records FB page…but don’t want to flood that site and my friends with my blog.
UT does add air IMV but getting the audible range right is far more important than the extremes. If you want to use the argument of extended highs then what about response down to <10Hz, far more difficult to achieve and lots more money.
Have you had your ears tested yet?
It is very difficult to achieve infrasonics but I’ve heard it done at Meyer sound. My mix room goes to 16 Hz but it took 2-18 inch drivers and 1200 watts.
I had my hearing checked at last year’s NAMM show and the guy in the trailer told me I had the hearing of a 20 year old. I don’t think he was pulling my chain. I’ve been very careful with my hearing my entire life.