Altec Build

[GM]

B, C performance should be the same AFAIK and at least the lone 'C' I compared to a 'B' in a pair of A7-500s at the distributor when they came out sounded the same to me, but GPA will have to confirm or highlight any differences. Again, the 'G' is closest to the original 515, but for smaller horns and/or vented, the 'B' was/is my fave.

WRT the 'B's mids, they 'suffer' referenced to the original in 'A' series horns, i.e. the latter has a wider/stronger break-up modes BW to keep up with the higher gain of the big horns, so not an issue with smaller horns and/or vented.

Yes, the 817 is vented to a ~ 55 Hz Fb.

GM

[bowtie427ss]

So all 4 must be reconed as 515Bs.

Sell them all "as is" and buy 4 new ones from GPA. You can likely come out a bit ahead, and you'll help preserve another pair of original 515's a bit longer. IMO, to destroy a pair of good original 515 cones hinges on being a sacrilegious act.

[Altec Best]

Jeff I don't think GPA has the same cones you have on those.The 515 came with a paper surround.I would leave them.

Complication. GPA confirms no 515 original cones. So all 4 must be re-coned as 515Bs.

Sell them all "as is" and buy 4 new ones from GPA. to destroy a pair of good original 515 cones hinges on being a sacrilegious act.

I agree you could sell them and buy 4 brand new ones ! And you would have 4 new ones that all should be matched similarly

[jeffjmr]

I agree you could sell them and buy 4 brand new ones ! And you would have 4 new ones that all should be matched similarly

OK, I hear you. Preservation is important, and I am motivated to keep the originals in deference to my departed friend. I will get them out of storage, post some pictures to evaluate whether VolvoHeretic's home repair idea shows promise.

If that turns out to be practical, should they go to GPA anyway for remagging?

I like those AutoTech horns. Need some brushing up on my theory though to choose the right ones for the 288s and N500Cs.