Anybody need 411's?

[Art J.]

These obviously are not foam surrounds. They came from an unknown year from the Barcelona. I would think foam would be preferable for a large subwoofer? I'd hate to have them redone in foam for financial reasons and would it benefit the purpose?

Your number 391205 means Built the fifth (05) week of 1972 (2) by (391) Altec.
They look in great shape............

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Hey Ron SS, if your out there I'd like to know a bit about those 411 subs you made. They look nice. Can't seem to get much of a response from the audio engineers out there although I respect there Knowledge on many topics. Kind of wish I'd learned the audio field early on (probably less boring) than flying 757s for a living...

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Thanks Art J., Just saw your reply...

[RonSSS]

Those are clearly early versions and would probably measure spot on to the original specs.
therfore, they would be best suited to a sealed enclosure like the Barcelona or the 9846?.

they do look pristine! Good find.

i'm not sure what the internal volume should be.

I put mine in vented because the T/S parameters didn't dictate a sealed box.

Until someone else measure the T/s parameters of Bill's recent 411 recones, hard to say what they measure.

Ron

These obviously are not foam surrounds. They came from an unknown year from the Barcelona. I would think foam would be preferable for a large subwoofer? I'd hate to have them redone in foam for financial reasons and would it benefit the purpose?

[Altec Best]

Until someone else measure the T/s parameters of Bill's recent 411 recones, hard to say what they measure.

Hey Ron, I have a pair of recent recones from Bill will do when time permits.

[Old Guy]

IIRC Altec recommends a sealed 4.5-8 cu ft enclosure.But it has to be sealed !

Absolutely airtight they will thrive as subs. They were designed for a sealed box.

I've never seen "have to" in print.

But do you really think technology has been static since the 70's? We did not have PC's to model speakers on then.

If you don't know what you are doing stick with sealed. But I can't see any reason not to use a properly designed vented box, especially if you actually measure them and build to that.

[Earl K]

Until someone else measure the T/s parameters of Bill's recent 411 recones, hard to say what they measure.

- Johns 411s were pretty recent GPA recones ( originally done for Robertbartsch back in early 2009 ) / if I remember the lineage & time-line correctly ( 411-8As rebuilt by GPA ).

<> cheers

[Old Guy]

Someone mentioned bass horns.What was that about?

I really do not see the 411 as a good driver for bass horns.

3154 is a better shot, but should be hi-passed below horn cutoff.

Bear in mind a 210 or 828 is NOT a bass horn...

[Altec Best]

I've never seen "have to" in print.

But do you really think technology has been static since the 70's? We did not have PC's to model speakers on then.

If you don't know what you are doing stick with sealed. But I can't see any reason not to use a properly designed vented box, especially if you actually measure them and build to that.

Yeah I was just going by the Altec literature.I forget the gentleman's name who designed the 411.It was with a 4" VC the only 4" that they made and recommended sealed enclosure.Don't worry Brad already pointed that out to me. I even considered using them in my VENTED box.

[Altec Best]

- Johns 411s were pretty recent GPA recones ( originally done for Robertbartsch back in early 2009 ) / if I remember the lineage & time-line correctly ( 411-8As rebuilt by GPA ).

<> cheers

Yep, I got those from Robert.I have the GPA receipt with them.