[lini]

Cd players usually only do 20 Hz - 20 kHz, the rest is filtered. Those 5-Hz-cds appear to be a joke...

Greetings from Hannover!

Manfred / lini

 

[remcoy]

the cd format only contains frequencies between 20hz-20khz period.

 

[setmenu]

Quote:

Originally Posted by remcoy the cd format only contains frequencies between 20hz-20khz period.

I have a test CD with a 0-22khz sweep.
It certainly contains frequencies below the quoted 20hz , I have observed
a transducer diaphragm gently beginning the above sweep with a too and fro
movement increasing in frequency until movement is no longer visible.




Setmenu

 

[kramer5150]

Quote:

Originally Posted by setmenu I have a test CD with a 0-22khz sweep. It certainly contains frequencies below the quoted 20hz , I have observed a transducer diaphragm gently beginning the above sweep with a too and fro movement increasing in frequency until movement is no longer visible. Setmenu

Yeah Ive seen 1 cycle/second... its pretty funky looking to see a cone move that slow. I think there are some videos at realmofexcursion.com


Garrett

 

[mattpwill]

I haven't read all the thread, but it's a ridiculous exercise, because you're lucky if you can hear down to 20Hz, and also, below your hearing threshold, your body can only feel it.

With headphones, you can't feel frequencies below your hearing threshold. It's a totally different experience to using speakers and a subwoofer. I'd highly recommend just getting really good headphones

 

[grox]

Look. The consensus is that a) headphones rated under about 20hz may not perform that way and b) that if they could it would be difficult to hear them, depending on how good your hearing is.

I assume what you're saying is that because you watch movies/listen to movies with bass, you want headphones with a good low end (bass).

Be aware that some cans, eg. beyerdynamic dt-770s can give you too much bass which can and has resulted in people getting bass headaches - you really can have too much of a good thing. But if your source chain is set up right (eg cd-->amp-->headphones) you may not have this problem.

Narrow down your type of music (eg. techno/trance), use the search button based on your preferences and research your cans, ask questions if you need to

If you listen to rock/classical try grado, etc, etc.

Have fun and sorry about your wallet!!

 

[pbalcer]

Quote:

Originally Posted by craiger33 BUT I am listening to these sets of CD's that require my headphones to be able to handle a very low frequency, they need to be rated down to 5 HZ!

I'm just curious: what kind of recordings require 5 Hz??? Tectonic movements? Submarines?

As far as I'm aware, most musical material on CDs rarely extends below 40 Hz. It is said that humans can hear down to 16 Hz only. What is this 5 Hz thing that you're trying to listen to?

I don't know of any headphones capable of reproducing frequencies down to 5 Hz. Sennheiser claims that their HD280 can go as low as 8 Hz but people say they "have no bass" so my guess is that their reproduction of 8 Hz frequencies is barely audible - if audible at all (-> 16Hz limit of the human hearing).

 

[White Fox]

This thread is killing me. Keep up the good work, guys!

The HD 280s have great low-end extension to my ears. It's the upper bass that is lacking impact, and the reason I think people say they 'have no bass'.

 

[ilovesocks]

Quote:

Originally Posted by pbalcer I'm just curious: what kind of recordings require 5 Hz??? Tectonic movements?

That's hilarious!

North American and Caribbean Plate Duet, Movement 1: Subduction

I'm playing low-frequency test tones through my AKG 271s and above 6 Hz I can feel the air against my ears if I really crank the volume, but I can't hear anything. At 5 I can't hear or feel anything. This is strange because they're only rated down to 16 Hz (again, the limit of human hearing).

 

[craiger33]

Well..., LOL, that's what happens when you sign up on a new board, post a question like that and then go to sleep eh? LOL

Anyway, thanks for all of the input... I am pretty knew to the whole conversations, but yes- I am aware I won't actually be able to "hear" down to 5 HZ, but the set of CDs I'll be listening to allegedly DO have waves that low, and I believe them (now maybe I'm a sucker, but to honest I really don't think so).

Quote:

Originally Posted by fappar well of course you won't be able to hear it conciously. I assume that this is some kind of aural hypnosis? Your brain will still pick up the sounds, regardless of volume (and -9258 or whatever is really ****ing loud)

fappar, you came the closest to guessing, it's not quite hypnosis- technically they are meditation CDs. Allegedly it's a VERY high tech studio using some VERY advanced processes to embed the waves in various ways/levels (much of which is way over my head).

I was tempted to included this information in my first post, but as I looked around the board I see that people have some very strong opinions around here and didn't to be touted as a nutball my first post, lol. But you can begin the comments now if you wish. Say all you want, but these CDs KICK ASS!

What's disturbing is that so many people are saying that the spec sheets aren't accurate... that feels... like false advertising or something... if I can't shop the spec sheets, this project really sucks! Some are saying that the headphones will never reproduce this level.... and that's disturbing too...

I wonder if I can get someone from their company to comment on what I've heard in this thread... don't know if they'd take the time, but given all the energy around this- it's at least worth a try, eh?

I have to get to work, but I'll for sure check back later. I'll see if I can call or e-mail them later with some of the comments here and see what their response is. I'm SUPER crazy busy with my software company I, but I'll post again when I can for sure. Meanwhile, if anyone knows of a company that actually has spec sheets that I can BELIEVE that would be great...

One post said to just listen to a few... but you can't hear that low... and if you can't hear that low, I thought shopping the spec sheets would be the best way to go... this is interesting, but slightly frustrating as well.

Anyway, thanks everyone for your input... I'm still on the quest to find cans that I believe will go that low, and not spend a fortune on them.

I'll let you know how the company responds to some of your comments... if you have any specific questions for them, post them and I'll see if I can get them answered for you.

Thanks for your time and attention!

 

[Sugarfried]

Quote:

Originally Posted by pbalcer I'm just curious: what kind of recordings require 5 Hz?

There are some meditation CD's that use a psychoacoustic model (difference beats) to generate these lower frequencies. We've taken questions from people who use these CD's - they ask if our earphones produce sound at 5Hz and 10Hz. But in reality the listening device is not required to produce those frequencies.

Instead, to produce a stimulus of 10Hz you may use tones of 500Hz and 510Hz, or 400Hz and 410Hz, or 800Hz and 810Hz, and so on and so on... hence the name difference beats. By producing two tones that are 10Hz apart the psychoacoustic effect is a 10Hz tone. You may not hear it, but it's there.

The only requirements are that the tone is heard well enough, and that it is below 1000Hz. Usually these tones are inserted behind ambient sounds (water, wind, etc.) or music of some sort.

I'm guessing that some people who are interested in headphones that extend to 5Hz have seen the "soothing 5Hz tones on CD" advertisement or something.

 

[kramer5150]

OK that clears things up a little....

I honestly dont think cans are going to go that low. Im guessing a DT770-80 extends to ~30 flat, it WILL play lower than that but will be gradually rolled off and not flat. My triad Bronze HT sub has the lowest extension Ive heard for a $1200 10" sub... but it "only" extends to ~22 Hz flat, and even then its exciting some room acoustics to achieve that impact.

Garrett

 

[JB.]

Craiger33, you can test your hearing free of charge. Go to this link and click the "WWW Hearing Test Professional." The test tones start out at 20 Hz.

 

[bubbagump]

Quote:

Originally Posted by calcetin well, actually you can't hear frequencies bellow 15-20 Hz, the 5 Hz rating of those headphones (or any spekaer in fact) is pure marketing. you don't need headphones rated to 5 Hz because those signals are usually filtered.

yea enjoying 5hz in a headphone isnt going to happen. However in some special circumstances in tuned port enclosures I've heard of woofers that can go this low, almost. You can't hear it apparently, but you swear the earthquake is real. I would love to experience that.

 

[shimage]

I would comment on the thread topic, but I think it's been amply covered... However, it seems that some people are having problems with definitions ...

Quote:

Originally Posted by EdipisReks i'm not an audio engineer, but my understanding of negative 9258 db is that it is a crazy exaggeration of inaudible.

You are right. dB is a deciBel, that is, one tenth of a Bel, defined as the base-10 logarithm of some ratio (can't take a logarithm of something with units ... although I've seen some intelligent people try). dB is never an absolute measure for that reason; it needs to be measured WRT something (and no, it can't be zero --> log(0) = -inf). What better reference than full-scale (especially with digital ...). So 0 dB is full scale, and you usually measure the volume as the attenuation from full scale. On the other hand, when you say "A rock concert is 110 dB", you're using the loudest sound that you can't hear as the reference. In any case, -9000 dB = 10^(-900), which is pretty small... (btw, anyone know how to include html so that it isn't escaped?)