Odd bod rear vented '515B'

**magnarc** · April 22nd, 2012, 03:40 AM

TWO VERY NICE ALTEC 515C 515 C WOOFERS SPEAKERS !! | eBay

It's obvious that the labels are stuck on from somewhere, but I'm curious as the cones are the correct 515B part number, yet the mags are drilled through, possibly for rear venting, or are these possibly 604s resprayed and with no HF?

**mah** · April 22nd, 2012, 05:14 AM

Unusual in that there is no labelling on the back.

**bowtie427ss** · April 22nd, 2012, 07:17 AM

They're correct 515C's. The foilcals are missing.

Most 515C's that have seen much handling will have indentations to some extent in the foilcals that reveal that hole underneath. I'm all but sure that the same part was used for the return pots on 515's and 604's from this point on.

My WAG is that this was a cost cutting measure whereby the previous solid return pot design of the 515 and 515B was abandoned for a "one size fits all" part.

Certainly this is one reason the original 515's and 515B's are valued so highly.

**Altec Best** · April 22nd, 2012, 10:58 AM

At the present time they look to be venting from the front and the back with the missing foilcals.

altec

**bowtie427ss** · April 22nd, 2012, 11:41 AM

I'm not close to an expert on 515's but i'd wager the C versions had a solid polepiece, and that hole is only as deep as the thickness of the return pot. Hopefully, they didn't resort to gluing a metal disc over the hole at the front of the polepiece as was done with some 416-8C's.

**Altec Best** · April 22nd, 2012, 01:22 PM

Originally Posted by bowtie427ss

Hopefully, they didn't resort to gluing a metal disc over the hole at the front of the polepiece as was done with some 416-8C's.

As they were known to come loose and rattle around in the woofer.

**magnarc** · April 23rd, 2012, 01:29 AM

But... they are 15 inch frames. I thought all 515Cs (and the late Bs) were on the 16 inch frame.
Unless its a marriage again...
Thanks for clearing the magnet up.

**bowtie427ss** · April 23rd, 2012, 07:29 AM

Originally Posted by magnarc

But... they are 15 inch frames. I thought all 515Cs (and the late Bs) were on the 16 inch frame.
Unless its a marriage again...
Thanks for clearing the magnet up.

You're absolutely right, those magnets do not belong on those frames, at least according to the factory lit.

The factory pics from '78 show 515C as having the "old style" motor pot on the new style 16 inch frame.

But, then there's this factory sheet for the 515C: http://altecpro.com/pdfs/vintage/Spe...%20Speaker.pdf

I'm voting "marriage".

**stéphane Rame** · April 23rd, 2012, 12:36 PM

Hi,
The B and C are similar, it did not change the picture?
http://altecpro.com/pdfs/vintage/Spe...%20Speaker.pdf
http://altecpro.com/pdfs/vintage/Spe...%20Speaker.pdf

St?phane

**magnarc** · April 24th, 2012, 02:53 AM

Maybe Stepahne is right there, same pic.

I love this odd bod Altec stuff.... Sometimes these pristine factory 515Bs and 288Cs just get sooooo boring...