Alnico,Neo and Ferrite magnets sound different?

[Rajiv]

Hi,

I heard the Lowther Ferrite and Neo. Ferrite seemed a little sluggish in comparison. I do not know if this observation is valid for all brands.

A bit more on the subject of magnet material in speakers.

First, a disclaimer: many audiophiles, probably most, can't hear the differences between magnet materials. They sound like the difference between transformer core materials - similar to the difference between 80% nickel, M6 steel, and amorphous cores. If you've not heard that kind of difference for yourself, the fairly subtle differences between driver magnets may not be audible. It is less audible than the much grosser effects of diaphragm resonance, horn modes, horn diffraction, internal standing waves in the cabinet, cabinet edge diffraction, and crossover design errors. The more severe effects of these dominate the sound of most high-end loudspeakers on the market; all of these design errors are audible in the first seconds of listening if you have some experience in designing loudspeakers.

To my ear, field-coils, Alnico, and neodymium magnets are all noticeably better than ceramic magnets - for lack of a better word, they have a "fresher", more vivid, more colorful sound. The field coils sound a bit quieter, more understated, while the Alnicos have a more vivid, more colorful sound. Neo sounds partway to the duller sound of ceramic, while having a fair amount of Alnico's vividness. Some say neo can sound "brash" on some program material, but a lot depends on details of gap saturation and magnetic path design.

This is a purely subjective assessment on my part, and not shared by other loudspeaker designers. Many designers - who I respect as good engineers who know their stuff - are convinced there is no audible difference between magnet materials at all, but then they listen to Class AB transistor amplifiers - we live in different subjective worlds. I find the sound of nearly all Class AB transistor amplifiers to be dull and flat, with much less resolution, tonal color, and spatial dimensionality than vacuum-tube amplifiers, particularly zero-feedback all-triode amplifiers.

Beyond the Ariel - Page 769 - diyAudio

Lynn is not alone.Here is what Greg Timbers has to say about alnico magnets in speakers,and Greg knows a thing or two about speakers and speaker design.

Ferrite magnets do not demagnitize with time or drive. They are affected by temperature but that is reversible. They will return to normal when they return to room temperature. Ferrite is basically a lousy magnet material for speakers but it is cheap and readily available. JBL has done a ton of things within the magnetic circuit to make the material behave in a more stable manner. At 100 degrees F, a Ferrite motor will be down about 1.5 dB in level which means the midband of the woofer will be lower by that much and there will be increased output around the system resonance. The TS parameters will be completely different - as though the BL was reduced by about 18%.

Alnico magnets, by their nature are easy to demagnitize with drive. They will not change with time and their dependence on temperature is really small - maybe 1% at 100 deg.F. s. Alnico stability and resistance to back EMF is really good. This is why they make the best sounding magnetic structure

Recharging Alnico/Ferrite magnets - Page 2

GREG TIMBERS

Regards
Rajiv

 

[Rajiv]

Hi,

I heard the Lowther Ferrite and Neo. Ferrite seemed a little sluggish in comparison. I do not know if this observation is valid for all brands.

Prem, you heard right.

A bit more on the differences between magnet materials in speakers.

First, a disclaimer: many audiophiles, probably most, can't hear the differences between magnet materials. They sound like the difference between transformer core materials - similar to the difference between 80% nickel, M6 steel, and amorphous cores. If you've not heard that kind of difference for yourself, the fairly subtle differences between driver magnets may not be audible. It is less audible than the much grosser effects of diaphragm resonance, horn modes, horn diffraction, internal standing waves in the cabinet, cabinet edge diffraction, and crossover design errors. The more severe effects of these dominate the sound of most high-end loudspeakers on the market; all of these design errors are audible in the first seconds of listening if you have some experience in designing loudspeakers.

To my ear, field-coils, Alnico, and neodymium magnets are all noticeably better than ceramic magnets - for lack of a better word, they have a "fresher", more vivid, more colorful sound. The field coils sound a bit quieter, more understated, while the Alnicos have a more vivid, more colorful sound. Neo sounds partway to the duller sound of ceramic, while having a fair amount of Alnico's vividness. Some say neo can sound "brash" on some program material, but a lot depends on details of gap saturation and magnetic path design.

This is a purely subjective assessment on my part, and not shared by other loudspeaker designers. Many designers - who I respect as good engineers who know their stuff - are convinced there is no audible difference between magnet materials at all, but then they listen to Class AB transistor amplifiers - we live in different subjective worlds. I find the sound of nearly all Class AB transistor amplifiers to be dull and flat, with much less resolution, tonal color, and spatial dimensionality than vacuum-tube amplifiers, particularly zero-feedback all-triode amplifiers.

Beyond the Ariel - Page 769 - diyAudio

Lynn Olson is not alone,Greg Timbers has this to say about ferrite magnets. Greg Timbers knows a few things about loudspeakers.

GREG TIMBERS

Ferrite magnets do not demagnitize with time or drive. They are affected by temperature but that is reversible. They will return to normal when they return to room temperature. Ferrite is basically a lousy magnet material for speakers but it is cheap and readily available. JBL has done a ton of things within the magnetic circuit to make the material behave in a more stable manner. At 100 degrees F, a Ferrite motor will be down about 1.5 dB in level which means the midband of the woofer will be lower by that much and there will be increased output around the system resonance. The TS parameters will be completely different - as though the BL was reduced by about 18%.

Alnico magnets, by their nature are easy to demagnitize with drive. They will not change with time and their dependence on temperature is really small - maybe 1% at 100 deg.F. Alnico stability and resistance to back EMF is really good. This is why they make the best sounding magnetic structures.

Recharging Alnico/Ferrite magnets - Page 2

Regards
Rajiv

P.S. I had posted this earlier this afternoon but to my surprise I found the post missing(deleated?). I wonder what happened. Is it OT?

 

[Rajiv]

Hi,

Prem has posted his preference for the sound of Neo magnet Lowther drivers in this thread.

http://www.hifivision.com/active-sp...00fe-co-ax-drivers-based-active-speakers.html

I posted the following also in the thread but to my surprise it was deleted. Not once but twice and no reason has been given for the deletion. Therefore the new thread.

Hi,

I heard the Lowther Ferrite and Neo. Ferrite seemed a little sluggish in comparison. I do not know if this observation is valid for all brands.

Prem, you heard right.

A bit more on the differences between magnet materials in speakers.

First, a disclaimer: many audiophiles, probably most, can't hear the differences between magnet materials. They sound like the difference between transformer core materials - similar to the difference between 80% nickel, M6 steel, and amorphous cores. If you've not heard that kind of difference for yourself, the fairly subtle differences between driver magnets may not be audible. It is less audible than the much grosser effects of diaphragm resonance, horn modes, horn diffraction, internal standing waves in the cabinet, cabinet edge diffraction, and crossover design errors. The more severe effects of these dominate the sound of most high-end loudspeakers on the market; all of these design errors are audible in the first seconds of listening if you have some experience in designing loudspeakers.

To my ear, field-coils, Alnico, and neodymium magnets are all noticeably better than ceramic magnets - for lack of a better word, they have a "fresher", more vivid, more colorful sound. The field coils sound a bit quieter, more understated, while the Alnicos have a more vivid, more colorful sound. Neo sounds partway to the duller sound of ceramic, while having a fair amount of Alnico's vividness. Some say neo can sound "brash" on some program material, but a lot depends on details of gap saturation and magnetic path design.

This is a purely subjective assessment on my part, and not shared by other loudspeaker designers. Many designers - who I respect as good engineers who know their stuff - are convinced there is no audible difference between magnet materials at all, but then they listen to Class AB transistor amplifiers - we live in different subjective worlds. I find the sound of nearly all Class AB transistor amplifiers to be dull and flat, with much less resolution, tonal color, and spatial dimensionality than vacuum-tube amplifiers, particularly zero-feedback all-triode amplifiers.

Beyond the Ariel - Page 769 - diyAudio

Lynn Olson is not alone,Greg Timbers has this to say about ferrite magnets. Greg Timbers knows a few things about loudspeakers.

GREG TIMBERS

Ferrite magnets do not demagnitize with time or drive. They are affected by temperature but that is reversible. They will return to normal when they return to room temperature. Ferrite is basically a lousy magnet material for speakers but it is cheap and readily available. JBL has done a ton of things within the magnetic circuit to make the material behave in a more stable manner. At 100 degrees F, a Ferrite motor will be down about 1.5 dB in level which means the midband of the woofer will be lower by that much and there will be increased output around the system resonance. The TS parameters will be completely different - as though the BL was reduced by about 18%.

Alnico magnets, by their nature are easy to demagnitize with drive. They will not change with time and their dependence on temperature is really small - maybe 1% at 100 deg.F. Alnico stability and resistance to back EMF is really good. This is why they make the best sounding magnetic structures.

Recharging Alnico/Ferrite magnets - Page 2

Regards
Rajiv

 

[captrajesh]

I didn't do a one on one comparison so don't know how much of the differences I heard could be attributed to the type of magnet but the vintage drivers that I heard like Altecs and Tannoys sound special. The tone and timbre of the instruments and even the vocals are addictive, especially when paired with Single Ended Tube amplifiers.

 

[HiFiVision]

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