421-8H Question

[Bill F777]

What is the difference between a 421-8H and a 421-8H Series 2 woofer. Thanks!

[bowtie427ss]

I think it's just the frame/basket.

421-8H is a rear mount early style frame, and the 421-8HII is the later type frame with the wide gasket that can be front or rear mounted to the baffle.

[GM]

FWIW, the published specs are different enough to imply either a motor design change and/or different cone/VC kit.

GM

[Old Guy]

The Frames are not a predictable thing.

The new ones were used as old ones ran out.

The poop from Altec at the time was the II had a much improved coil. I believe the cone to be the same.

Motor changes are quite possible too, do not remember ever discussing it.

[bowtie427ss]

Sorry guys, i just looked at the GPA parts list and saw that they both use the same parts for rebuild and made the dangerous assumption.

I could only find a data sheet for 421-8H, but compared to the catalog specs of the 421-8H II they are surely different.

[417 - Alnico]

What is the difference between a 421-8H and a 421-8H Series 2 woofer. Thanks!

http://www.lansingheritage.org/image...-mi/page07.jpg

http://www.lansingheritage.org/image...-mi/page04.jpg

http://www.lansingheritage.org/image...pro/page14.jpg

http://www.lansingheritage.org/image...hort/page4.jpg

http://www.lansingheritage.org/image...ro/page_2b.jpg

http://www.lansingheritage.org/image...-mi/page04.jpg

[417 - Alnico]

Sorry guys, i just looked at the GPA parts list and saw that they both use the same parts for rebuild and made the dangerous assumption.

I could only find a data sheet for 421-8H, but compared to the catalog specs of the 421-8H II they are surely different.

Here are some PDF's... I did not check to see if they are duplicates of the web pages above though.

http://www.altecpro.com/products/vin...x.htm#speakers

[bfish]

IIRC, the IIs went to copper voice coil windings (previously aluminum) to meet the higher power demands of the day. When the IIs first came out, they had a lifetime warranty. The copper coils added mass, accounting for the parameter change.

Added;
Duhh.. shoulda just read the '75 MI catalog page 417 linked above;

"The ?H Series II speakers are the high powered versions of the old reliables. They feature special heat dissipating aluminum coil supports and ultra rugged copper voice coils that allow you to play louder for longer periods of time. with much less worry of burn out."