Converting 921-8A to a 416?

[oface1]

Was looking back at some old post and stumbled upon one where a person asked about his 421's MI speakers. Someone suggested that he re-cone them to 416's.

That got me scratching my head since I have 8 921's that are sitting in some 817 cabs not being used.

Was wanting to use 2 of them and wondered if I send them to Bill @ GPA if they can convert them to a modern equivalent 416.


I also went to the Altec Pro site and look up both speakers (921-8a compared to a 416-8c) specs. They both almost exact except for the 921's increased Flux density.

921-8A's

416-8C's

Would the Fluxe density be a barrier in me attempting the conversion. Would there be a negative or positive effect?

Or should I skip the idea all together and just worry about getting these 414's I got from OG's brother reconed? Was looking at maybe sending in both pairs at once to get it over with all at once.

Thanks for any answers/ suggestions.


-chris

<font color="#FFFFFF" size="1">[ November 14, 2008 11:14 AM: Message edited by: oface1 ]</font>

[bowtie427ss]

Entirely opinion here, but i'd be inclined to suggest leaving the 921's alone if they're in good working condition since you have a nice even number of pairs and cabinets for them.

As far as converting 921 to a 416, i'm not sure about the ramifications of that. The higher flux density might be the product of a shorter gap and field for which the 416's moving assembly is not designed or appropriate, just my WAG.

Because the motors are "different", even tho the 416 parts might load up and "work", the end result will probably not have the parameters/characteristics of either the 921 or 416............. not exactly anyway.

I'm no expert at all among many here who are, so best i leave the reasoning up to them.

[Old Guy]

A straight conversion is not at all possible.

The 416 is front vented, 421 and 921 are rear vented. So a solid dust cap would have to be substituted in the 416 kit.

The flux density would cause more mid band gain, if I'm wrong on that I'm sure somebody will correct me.

So what you will end up with is a unit with more mid than a 416 and less than a 421/921.

All in all- if the 921's are working, sell them. Then add the money you would have spent on reconing. That should buy a clean set of 416's.

Reinventing the wheel often doesn't work.

[oface1]

Well, looks like I will sell the lot.

I was going to use the proceeds for 604's anyway.


Thanks again fellas for the info.

[VancouverSound]

Years after the fact...

I'm planning on buying some 921-8A's and I wish I could find some 817's nearby but that's unlikely. I did manage to track down 4 816's; two in my town and two about 1,500 miles away... had them shipped by Greyhound. Believe it or not they'll take them as long as the access panels are an extra package which lowers the weight.

I'm hoping to find some 921's easily. There are plenty out there... If it was to be used outside of a home and you actually wanted to hear it you needed to buy some more powerful drivers cuz grandpa's weren't up to it. Don't get me wrong, I love Altec dearly which is why I just bought 4 816's and 4 809-8A crossovers but Altec stuck to what they knew while JBL and other's started producing improved drivers and altec lost market share at an apocalyptic scale... Their demise wasn't moving production overseas... Moving overseas was an attempt to make profit for a change cuz there were no more customers.

I'll bet there's lots of 416's out there that don't sound right and don't have labels on the back because people changed the cones to 416's from anything else. Leaving any driver alone is wise for technical reasons and as stated by another member they should be left alone just because.

Maybe I'll find some mint 921-8A's with labels on them if I talk about it enough.

[bowtie427ss]

Altec stuck to what they knew while JBL and other's started producing improved drivers and altec lost market share at an apocalyptic scale... Their demise wasn't moving production overseas... Moving overseas was an attempt to make profit for a change cuz there were no more customers.

Thank you for the history lesson, always interesting to see others' interpretations.

If it was to be used outside of a home and you actually wanted to hear it you needed to buy some more powerful drivers cuz grandpa's weren't up to it.

Why not load them with 2226's?

[Old Guy]

Years after the fact...

I'm planning on buying some 921-8A's and I wish I could find some 817's nearby but that's unlikely. I did manage to track down 4 816's; two in my town and two about 1,500 miles away... had them shipped by Greyhound. Believe it or not they'll take them as long as the access panels are an extra package which lowers the weight.

I'm hoping to find some 921's easily. There are plenty out there... If it was to be used outside of a home and you actually wanted to hear it you needed to buy some more powerful drivers cuz grandpa's weren't up to it. Don't get me wrong, I love Altec dearly which is why I just bought 4 816's and 4 809-8A crossovers but Altec stuck to what they knew while JBL and other's started producing improved drivers and altec lost market share at an apocalyptic scale... Their demise wasn't moving production overseas... Moving overseas was an attempt to make profit for a change cuz there were no more customers.

I'll bet there's lots of 416's out there that don't sound right and don't have labels on the back because people changed the cones to 416's from anything else. Leaving any driver alone is wise for technical reasons and as stated by another member they should be left alone just because.

Maybe I'll find some mint 921-8A's with labels on them if I talk about it enough.

If you can't find 921 go for 421lf

[Altec Best]

There was somebody selling a whole bunch of 817's not long ago.. The gray matter isn't what it used to be..

[Elitopus1]

I know there was a guy selling a whole 817 system on ebay. Something like 16 cabs. I guess he finally sold it because I don't see it listed anymore. Something like 32k he wanted.

I have 921-8a in my 817 cabs but they have been reconed to 16 ohm at some point. It bugs me because 3 of them have a very stiff suspension, while the 4th is very compliant. The 4th also has a different recone kit. I have been thinking about having them reconed as something else. I was also thinking about 416 cones w/solid paper dustcap. Maybe I should get some more authentic 421/921 style cone kits with aluminum dustcaps instead