You are here

Log in or register to post comments
Freako
Freako's picture
Offline
Last seen: 6 months 4 weeks ago
Joined: Jan 17 2010 - 8:29am
Does anyone know...

What would the benefit be in mounting extra (reversed) magnets behind drivers?

Thanks in advance

Kal Rubinson
Kal Rubinson's picture
Offline
Last seen: 2 hours 44 min ago
Joined: Sep 1 2005 - 9:34am
Re: Does anyone know...

It is sometimes done to reduce the effective external field which might have interfered with other device.

Kal

Freako
Freako's picture
Offline
Last seen: 6 months 4 weeks ago
Joined: Jan 17 2010 - 8:29am
Re: Does anyone know...

Does it help with controlling the membrane's movements?

Jan Vigne
Jan Vigne's picture
Offline
Last seen: Never ago
Joined: Mar 18 2006 - 12:57pm
Re: Does anyone know...

What Kal is referring to is a shielded speaker for use in close proximity to CRT's. An opposing magent is used to minimze the magnetic field of the driver's motor. Most often both magnets are then placed inside an aluminum can to further reduce the flux field. Placing an additional magnet outside the working area of the voice coil cannot have an effect on the diaphragm of the system. Even if it did, Freako, you would then be altering the parameters of the driver which the designer uses to create proper system integration.

Freako
Freako's picture
Offline
Last seen: 6 months 4 weeks ago
Joined: Jan 17 2010 - 8:29am
Re: Does anyone know...

I don't mind altering parameters, do it all the time.

The reason I asked is because I have glued two reversed magnets to the back of the magnets on my tweeters. I find it tightens up the treble a bit. Just wanted to know if anybody had any experience with this.

Jan Vigne
Jan Vigne's picture
Offline
Last seen: Never ago
Joined: Mar 18 2006 - 12:57pm
Re: Does anyone know...

Maybe there were too many fluxes bouncing around inside your cabinet.

geoffkait
geoffkait's picture
Online
Last seen: 5 min 3 sec ago
Joined: Apr 29 2008 - 5:10am
Re: Does anyone know...


Quote:
I don't mind altering parameters, do it all the time.

The reason I asked is because I have glued two reversed magnets to the back of the magnets on my tweeters. I find it tightens up the treble a bit. Just wanted to know if anybody had any experience with this.

Speaking of mind altering parameters, did you ever notice that stacking magnets doesn't increase the magnetic flux density?

No matter how well you do in the end, you would have done even better if you had had more to begin with. - Old audiophile expression

Freako
Freako's picture
Offline
Last seen: 6 months 4 weeks ago
Joined: Jan 17 2010 - 8:29am
Re: Does anyone know...


Quote:
Maybe there were too many fluxes bouncing around inside your cabinet.

Freako
Freako's picture
Offline
Last seen: 6 months 4 weeks ago
Joined: Jan 17 2010 - 8:29am
Re: Does anyone know...


Quote:

Quote:
I don't mind altering parameters, do it all the time.

The reason I asked is because I have glued two reversed magnets to the back of the magnets on my tweeters. I find it tightens up the treble a bit. Just wanted to know if anybody had any experience with this.

Speaking of mind altering parameters, did you ever notice that stacking magnets doesn't increase the magnetic flux density?

No matter how well you do in the end, you would have done even better if you had had more to begin with. - Old audiophile expression

When I think about it, yes you are correct.

It was just an experiment since I had two magnets lying around. Not that any of my existing speaker magnets are weak, I felt their power holding a screwdriver not so far away from the membranes! That's me in a nutshell when I tweak; I don't rely on "science" or tech, but use my ears (and an occasional screwdriver).

geoffkait
geoffkait's picture
Online
Last seen: 5 min 3 sec ago
Joined: Apr 29 2008 - 5:10am
Re: Does anyone know...


Quote:

Quote:

Quote:
I don't mind altering parameters, do it all the time.

The reason I asked is because I have glued two reversed magnets to the back of the magnets on my tweeters. I find it tightens up the treble a bit. Just wanted to know if anybody had any experience with this.

Speaking of mind altering parameters, did you ever notice that stacking magnets doesn't increase the magnetic flux density?

No matter how well you do in the end, you would have done even better if you had had more to begin with. - Old audiophile expression

When I think about it, yes you are correct.

It was just an experiment since I had two magnets lying around. Not that any of my existing speaker magnets are weak, I felt their power holding a screwdriver not so far away from the membranes! That's me in a nutshell when I tweak; I don't rely on "science" or tech, but use my ears (and an occasional screwdriver).

One pill makes you larger. And one pill makes you small. And the ones that mother gives you, don't do anything at all.

j_j
j_j's picture
Offline
Last seen: 2 years 6 months ago
Joined: Mar 13 2009 - 4:22pm
Re: Does anyone know...


Quote:
One pill makes you larger. And one pill makes you small. And the ones that mother gives you, don't do anything at all.

Now that was Slick, Gracie.

cyclebrain
cyclebrain's picture
Offline
Last seen: 3 weeks 6 days ago
Joined: Jun 16 2006 - 11:40pm
Re: Does anyone know...

This is one Fluxed up thread. The manufactures spend lots of time and money on the size of their magnets and the special material used that produce such high flux density. Then you guys attach flux cancelling magnets to the speakers that negate all of thier work. But at least you can brag about the wieght of the magnets used in your speakers.
Rubber Duck, is that you Dup? You just messing with us?

Freako
Freako's picture
Offline
Last seen: 6 months 4 weeks ago
Joined: Jan 17 2010 - 8:29am
Re: Does anyone know...

Oh dear! Dup's soul has invaded me... I am... I need to crank up the volume... arrghh... Help!

cyclebrain
cyclebrain's picture
Offline
Last seen: 3 weeks 6 days ago
Joined: Jun 16 2006 - 11:40pm
Re: Does anyone know...

Sorry for the insult.

Freako
Freako's picture
Offline
Last seen: 6 months 4 weeks ago
Joined: Jan 17 2010 - 8:29am
Re: Does anyone know...

None taken

One more proof: Dup had 4600 Watts delivered - I have 450 !

  • X
    Enter your Stereophile.com username.
    Enter the password that accompanies your username.
    Loading