[StrongEagle]

I'm referring to this Sansui Chopin speaker... http://www.herberts.org/sansui/Sansui.htm. Now, it's not the loudest speaker in the universe but if does go all the way down to 35 Hz. I've demonstrated with with a number of YouTube frequency generators running through the attached iPhone. Below 35 Hz, this speaker doesn't go silent... it begins to motorboat.

A couple of questions. How does it go so low? It's got maybe a 3 inch down firing speaker. And, why does it motorboat instead of going silent?

TIA - Apologies if this is in the wrong thread.

 

[Billy Boden]

The size of a speaker does not dictate how low it will go but how loud it will get at low frequency. It seems to be port tuned to 35Hz since it is loosing control below that frequency.

 

[Bill Fitzmaurice]

if does go all the way down to 35 Hz. I've demonstrated with with a number of YouTube frequency generators running through the attached iPhone.

It may go to 35Hz, but I doubt it. What you're probably hearing is the harmonics of 35Hz.

 

[darthray]

It may go to 35Hz, but I doubt it. What you're probably hearing is the harmonics of 35Hz.

Your Avatar, suit you so much
And love-it, you call an Ace of Spade, an ace of spade.


Ray

 

[totesmuhgoats]

It may go to 35Hz, but I doubt it. What you're probably hearing is the harmonics of 35Hz.

I don't know much about sound, can you explain what you mean by this?

 

[StrongEagle]

It may go to 35Hz, but I doubt it. What you're probably hearing is the harmonics of 35Hz.

So... I'm listening to a favorite piece of music with low bass tones and it sounds great... much better than the travel speakers I have... and you are telling me this is "harmonics"? What in the world do you mean?

 

[StrongEagle]

The size of a speaker does not dictate how low it will go but how loud it will get at low frequency. It seems to be port tuned to 35Hz since it is loosing control below that frequency.

Thank you... that's what I needed to know. And indeed, while this small box is plenty loud enough for a 15 x 15 room, it isn't much good for anything larger.

 

[Bill Fitzmaurice]

So... I'm listening to a favorite piece of music with low bass tones and it sounds great... much better than the travel speakers I have... and you are telling me this is "harmonics"? What in the world do you mean?

Google 'harmonic'. Instruments don't produce sine waves of a single frequency. They produce complex waveforms consisting of a fundamental tone and all of the harmonics of that tone. If said fundamental is lower than 70Hz or so you can remove the fundamental and not notice all that much of a difference, if any. This is the basis for the MaxxBass process.
http://www.waves.com/plugins/maxxbass
With respect to using a sine wave generator to identify frequency response 'by ear', it doesn't work. Even if the source is a pure 35Hz tone, for instance, a speaker incapable of reproducing 35Hz will create harmonics at 70Hz, 105Hz, 140Hz, 175 Hz, etc., and you will hear those harmonics. You could conclude that you're hearing 35Hz, when you aren't. When you add equal loudness (google it) and Hoffman's Iron Law (google it too) into the equation it's quite clear that a speaker that small cannot produce 35Hz at useful levels.

 

[bluewizard]

The problem is, that is an unqualified 35hz.

Most speakers are rated at low to high ±3db, some are rated low to high ±6db. Both are very usable. These are standards for true Hi-Fi speakers. However, tiny speakers like this are not remotely considered Hi-Fi, and they can claim anything they want.

It could be 35hz at -10db, it could be 35hz at -20db.

I had some Sony bookshelf rated at 80hz by a fair and reasonable standard, running test tones, I could play a 30hz tone and hear it nicely, though I had to crank the volume up. When the volume was enough to hear 30hz at a reasonably level, 80hz was crazy loud.

If you want to do a fair test of the speaker, play a 1khz tone and set the volume to a comfortable level, now play a 35hz tone and see if it is as loud as the 1khz tone? I doubt it.

There is the claim that people can hear from 20hz to 20khz, that is not really true. You might be able to hear those extreme, but not equally.

If you normalize the volume using a 1khz tone, then sweep down, I suspect you will not hear anything resembling a tone blow about 28hz, you will simply hear the fuff-fuff-fuff pumping of the speaker diaphragm.

Sweeping upward, I suspect most will have a hard time hearing over 16khz. Remember, you have to set the volume with a 1khz tone and LEAVE IT THERE.

Sure if you turn the volume up crazy loud, you might be able to hear 18khz, and if you are young, you might hear 20khz, but not at normal volume levels.

I would guess this tiny speaker is probably moderately flat from about 150hz (if you are lucky) to something in the 15khz to very doubtful 20khz.

Even tiny 3" and 4" speaker have very poor bass response. A very good 4" speaker might go down to 60hz though that is pushing it. A 3" driver is likely no deeper than about 80hzh to 100hz. A really tiny 2" drive is not remotely going to be flat below 100hz.

So, the 35hz claim in unqualified; 35hz relative to what?

Steve/bluewizard

 

[JHAz]

Hearing is so very brain based. Here is a site that will let you play pure sine waves or let you mix in more and more harmonics, ending in a sawtooth wave. You can clearly hear the difference between the pure sine wave and the sound with more harmonics. Hint - real instruments and voices all have harmonics above the fundamental that are critical to defining the particular instrument's sound http://www.seventhstring.com/tuningfork/tuningfork.html.

You control the wave shape with the slider on the right hand lower side. On my little speakers in my laptop, if the sound is turned up as loud as possible everywhere, I can hear that there is a tone at the F sharp below middle C (185 Hz - frequency is shown at top right). Below that frequency, it's silence to my ears in this not terribly quiet space. Simply by pushing the slider fully to the sawtooth wave, I can very easily hear the C two octaves below middle C, at about 65 Hz. And the note sounds way lower than that F sharp about an octave and a half higher, even though I know, with certainty, that zero of that 65 Hz fundamental is getting to my ears. It's really kind of amazing.

for me the practical application, in real life, is when some song comes on the radio in my car (especially on very bandwidth limited AM stations as bump music) that opens with say just bass and drums. I can hear the pattern of the bass guitar, but the fundamental my brain fills in often turns out to be incorrect once the rest of the instruments kick in. I might be assigning a pitch of a fifth or a third away from the real note based on how my brain integrates all those higher harmonics and "inserts" the fundamental.

It's fascinating to be a human.

 

[Greenwood Ave]

Even if the source is a pure 35Hz tone, for instance, a speaker incapable of reproducing 35Hz will create harmonics at 70Hz, 105Hz, 140Hz, 175 Hz, etc., and you will hear those harmonics.

Is this just if a speaker is *not* capable of producing a 35 Hz sine wave? So if a speaker *is* capable of producing a pure 35 Hz tone, will there then be no harmonics?

 

[kjfalls]

The 35Hz tone is considered the Fundamental tone. The harmonics are multiples of the fundamental (70, 105, 140, 174...). There will be harmonics, but normally at a reduced volume.

 

[Greenwood Ave]

The 35Hz tone is considered the Fundamental tone. The harmonics are multiples of the fundamental (70, 105, 140, 174...). There will be harmonics, but normally at a reduced volume.

So it sounds like what you are saying it that there are harmonics produced by both the speaker itself *and* the instruments/recording. Can one assume that the harmonics from the recording are much more significant than those produced by the speaker itself independently of the source? Just trying to get my mind around this.

 

[Bill Fitzmaurice]

So if a speaker *is* capable of producing a pure 35 Hz tone, will there then be no harmonics?

There are always harmonics. Even if they're not present in the signal the speaker itself will create them.

 

[beaveav]

Is this just if a speaker is *not* capable of producing a 35 Hz sine wave? So if a speaker *is* capable of producing a pure 35 Hz tone, will there then be no harmonics?

All speakers, no matter how good they are, will produce harmonics. But the better speakers will produce lower and/or fewer harmonics (ie, the speaker's harmonic distortion will be lower).

For example, a bookshelf/standmount speaker with a 6" woofer can produce 35Hz, but it will be low in level and will have relatively high levels of harmonics produced (ie, it's harmonic distortion at that frequency will be high). A 15" subwoofer can produce the same 35Hz at much higher levels and with relatively low levels of harmonics produced (ie, it's harmonic distortion will be lower for that frequency).

 

[beaveav]

So it sounds like what you are saying it that there are harmonics produced by both the speaker itself *and* the instruments/recording. Can one assume that the harmonics from the recording are much more significant than those produced by the speaker itself independently of the source? Just trying to get my mind around this.

In general, yes. Most modern speakers have fairly low harmonic distortion, with one key exception: the low bass. Most modern speakers, except huge towers with huge woofers, have high harmonic distortion when producing deep bass. That's where subwoofers excel - they can produce deep bass without adding as much harmonic distortion.

 

[Greenwood Ave]

In general, yes. Most modern speakers have fairly low harmonic distortion, with one key exception: the low bass. Most modern speakers, except huge towers with huge woofers, have high harmonic distortion when producing deep bass. That's where subwoofers excel - they can produce deep bass without adding as much harmonic distortion.

Thank you. Your explanation was very clear.