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Bookshelf or Floorstanding Speakers: Which Should You Choose? A guide

Rega

Hari Iyer

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Can you please explain why "clean" and "deep" is a function of the impedance?

Also, my response to rocksterraghu was for "Good speakers are able to deliver the whole frequency range at all volume levels"
FR is a function of impedance. FR=f(Z). Higher the impedance @ resonance lower will be the output at that frequency. Typically for a woofer the resonance freq will be in the range of 40Hz to 60Hz. If the box loading offer a high impedance at resonance (sealed enclosure) then the output at that freq will be lower. Hence most sealed enclosure are not capable to provide very low bass unless its resonance of the driver is below 30Hz or lower. You still need a high Vas to generate substantial air movement and quite a higher power amplifier.

In a bass-reflex enclosure you will have a low impedance at only that single particular freq (see its impedance curves) and will have 2 impedance peak at either side of its tuning freq. Hence most bass reflex gives a single freq boom bass.

Aperiodic & TL speakers have the advantage of quite a lower impedance at resonance (atleast 60% lower than the sealed counterpart). This ensures stable load for amplifier and lower electrical and acoustic impedance to the speaker system.:)
 

keith_correa

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FR is a function of impedance. FR=f(Z). Higher the impedance @ resonance lower will be the output at that frequency. Typically for a woofer the resonance freq will be in the range of 40Hz to 60Hz. If the box loading offer a high impedance at resonance (sealed enclosure) then the output at that freq will be lower. Hence most sealed enclosure are not capable to provide very low bass unless its resonance of the driver is below 30Hz or lower. You still need a high Vas to generate substantial air movement and quite a higher power amplifier.

In a bass-reflex enclosure you will have a low impedance at only that single particular freq (see its impedance curves) and will have 2 impedance peak at either side of its tuning freq. Hence most bass reflex gives a single freq boom bass.

Aperiodic & TL speakers have the advantage of quite a lower impedance at resonance (atleast 60% lower than the sealed counterpart). This ensures stable load for amplifier and lower electrical and acoustic impedance to the speaker system.:)
Then you meant "loud" and not "clean" and "deep". Agreed with most of what you say above.
 

Hari Iyer

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@ Keith

Most of the output from a TL speakers at and below the line tuning freq is from the terminus and not the woofer. A good test of a well designed TL speaker system is to check the woofer cone movement at low frequency. There will not be any major cone movement at low freq unlike a bass reflex or sealed enclosure design. This means the bass is not colored and is "clean".

This type of box loading is the only type capable of delivering an octave lower than the line tuning freq. If you have tuned your line @ 60Hz you can expect an lower end response of atleast 30Hz or lower with a proper designed TL with stuffing. Hence its "deep" too.

Hence both parameters have nothing to do with SPL (loudness) and is totally independent.
 
Last edited:

keith_correa

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@ Keith

Most of the output from a TL speakers at and below the line tuning freq is from the terminus and not the woofer. A good test of a well designed TL speaker system is to check the woofer cone movement at low frequency. There will not be any major cone movement at low freq unlike a bass reflex or sealed enclosure design. This means the bass is not colored and is "clean".

This type of box loading is the only type capable of delivering an octave lower than the line tuning freq. If you have tuned your line @ 60Hz you can expect an lower end response of atleast 30Hz or lower with a proper designed TL with stuffing. Hence its "deep" too.

Hence both parameters have nothing to do with SPL (loudness) and is totally independent.
Agree with what you say but that's the function of the transmission line. And my comment about "loud" was not overall SPL but SPL at frequencies below FS - my mistake there, I was not clear.
 

Rupam

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Although explained by Hari sir, I want to add that SPL is a consistent means to measure loudness. SPL meters can measure sound that is below our ability to hear (convention says <20Hz), but we can still feel. What an SPL meter can't measure is the listener's perceived loudness. Simple fact, some of us hear better than others. I think what you are trying to differentiate is if there is a difference between what we can hear and feel versus what we can only hear. The latter is what you are referring to as loudness. Look at this from the other end of the spectrum. There can be a very loud 30kHz sound, but you won't hear it. Doesn't mean it's not there. Just watch your dog and see how he behaves.
 

keith_correa

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There can be a very loud 30kHz sound, but you won't hear it. Doesn't mean it's not there. Just watch your dog and see how he behaves.
Ha! 30 Hz? I can hear that alright. And I don't even need it to be loud. BTW, dogs can hear from 64-44k. Depending upon the breed I'm sure. So, your analogy is all wrong. :D
 

vikasgme

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Hello everyone hifivision family,

I am vikas a student in Interning group. I am here for learning and sharing information about Interior designing , decorating House, office and impact on real estate businesses. Hope our journey gone well after spending lots of time spent together.
 
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