Neodymium vs shielded: better, worse or the same next to CRT?

[dstmbgh]

I'll be building a bass bin that will go directly under a CRT tv -- an old RCA console with an oak swivel base. I'm planning to use two Dayton Audio RS180S-8 woofers, which are "shielded." Can woofers (or a woofer) with neodymium magnets be used instead with equivalent results regarding not causing interference with the CRT?

[dstmbgh]

What's CRT, someone asked on the PE Forum

Cathode Ray Tube: a now antiquated technology for television and computer monitor screens long ago replaced by LCD and Plasma screens

Obviously, one that doesn't know what a CRT is also won't know the answer to my inquiry. (smile)

[cjd]

I guess Wolf's answer wasn't clear?

Yes. As far as shielding goes.

As far as being drop-ins for any design with the RS180S-8, ... not so much?

[fbov]

I suggested to the OP on Friday, in a different thread, that his shielded subwoofer project could use a neodymium sub, as well as what is effectively the bottom end of my NatP MTM (65L tuned to 32Hz). He's just checking facts, which I applaud especially when they come from me.

Plus, he's been building speakers longer than any of us, I suspect... long enough to take 25 years off!

HAve fun,
Frank

[dstmbgh]

Thanks, fellows. That's right...I'm not questioning anyone's credibility, but just seeking further clarification. Informing me that neo's are "inherently shielded" doesn't tell me if they're better, worse, or equivalent to a shielded ferrite magnet when situated immediately next to a CRT. I sure don't want to build my bass bin with the RS180S-8's, place it immediately under my CRT, only to discover that, in spite of being shielded, I'm still getting some interference issues -- issues that I would have been less likely to have with a neo because of their superiority when it comes to stray fields.

I'd pay a few extra bucks for a neo if there was a basis for greater confidence regarding a lack of problems with stray fields.

Just so you all know, I'm interpreting the statement from fbov and Wolf -- neo's are inherently shielded -- and, to the question "better, worse, or the same?", cjd's answer -- yes -- ...I'm interpreting this as... they're equivalent and neither one should give me problems with my CRT.

If anyone has reason to believe otherwise please let me know, or, if not, I'm ready to start making sawdust and use the RS180S-8's in fbov's alignment.

Thanks so much for all your help.

David

[cjd]

I think it comes down to the specific driver and the specific CRT for there to be clear differences. I've seen people set a CRT on top of a center directly, and I've seen people unable to do so despite shielded driver use.

On average, I believe a Neo driver may be more consistently shielded than some cheap options with ferrite, but the RS180S-8 is, to the best of my knowledge, pretty well shielded.

Sadly, I don't know anyone that's actually verified that.

C

[dstmbgh]

I think it comes down to the specific driver and the specific CRT for there to be clear differences. I've seen people set a CRT on top of a center directly, and I've seen people unable to do so despite shielded driver use.

On average, I believe a Neo driver may be more consistently shielded than some cheap options with ferrite, but the RS180S-8 is, to the best of my knowledge, pretty well shielded.

Sadly, I don't know anyone that's actually verified that.

C

This is helpful clarification. Thank you, C.

[5th element]

Just to throw the cat amongst the pigeons some neo motors aren't inherently shielded at all, so don't assume that a driver is if it doesn't say so in the datasheet.

[dstmbgh]

Just to throw the cat amongst the pigeons some neo motors aren't inherently shielded at all, so don't assume that a driver is if it doesn't say so in the datasheet.

Thanks for taking the time to enlighten me (us).