just got early unknown A7 type system

[Old Guy]

The 416A suggests closer to mid 60's. Before ~'64 the woofer would be an 803B.

My feelings too, say 64-68.

[kipduff]

The 416A suggests closer to mid 60's. Before ~'64 the woofer would be an 803B.

Regardless, nice set of matching components.

For giggles, any visible cone numbers on the back of the 416 cones?

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It's easier to do more harm than good, proceed with caution.

A blow dryer on low or medium will often soften the dope a good deal. Acetone(nail polish remover) will dissolve it, but if left too long may also start to work on adhesives.

clear white paint number on LF cone: 21184- and number on LF frame: 391612. number on HF driver: 391613. number on XO box: 613.

Blow dryer- thanks for the tip. Love this forum....

[Elitopus1]

You have original cones there. If you take off the HF rear covers, you can see if the diaphragms have the little Altec "L1", or whatever that mark is

[kipduff]

Date codes on components? 391xxx

GM

saw these numbers:

416A: ALC/50
802D: ALC/50
N-500-E: ALC/18

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Date codes on components? 391xxx

GM

Oh: you mean last three digits ('316) mean 13th week of 1963?

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saw these numbers:

416A: ALC/50
802D: ALC/50
N-500-E: ALC/18

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Oh: you mean last three digits ('316) mean 13th week of 1963?

correction: 16th week of 1963?

[magnarc]

391612 is the 12th week of 1966.
391613 is the 13th week of 1966.

[kipduff]

Date codes on components? 391xxx

GM

OK. I'm gonna get it right this time.

416A has 391612
802D has 391613
N-500-E has 613

12th and 13th week of 1966- is that correct?

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You have original cones there. If you take off the HF rear covers, you can see if the diaphragms have the little Altec "L1", or whatever that mark is

Yes- it has that.

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I can't find any data for DC voice coil resistance for my 16 ohm 802D HF drivers. I'm getting 9 ohms- is this correct? Are there T-S parameter data for HF drivers?

[BillWojo]

9 ohms sounds about right.

BillWojo

[mah]

Altec 16ohm LFs typical DCR is 11 to 12 ohm.

Check your meter on a similar value resistor. Check that you are using the correct range on your meter.

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EDIT: Low battery??

[Elitopus1]

He identified it as an Altec diaphragm. Probably have to take it out to find out the P/N on the back.

If they both read the same, I wouldn't be too worried about the DCR

[mah]

Oops. HFs. Ignore my reply.

Correction: See post #7 re early and later diaphragm different DCRs, here - Altec 806a driver help