HPM-100 Recapping

Hi all,

Just finished up a recapping of the x-over for a pair of my HPM-100s. This is my first pair of 100s and first successful recap project. I took the project one step further and decided to replace the original binding posts with new, heavy duty, banana plug type jacks. I really hate all those push pin type binding posts, but that was what everyone used in the 70's I guess. Even most vintage receivers did not use banana jacks, that are now common place on modern era receivers and amps. All parts came from Parts-Express.com. The larger binding posts were kinda of bear to get in as I had to drill out the old posts and make sure they contacted with the underside of the circuit board. It was trickier than I thought. There is very little extra room to add the size of posts I selected on the x-over pc board. In retrospect, I would use a smaller binding post.

I have included a link to a few pics of the finished product here. Also, a couple of surprises I found inside the speakers. You never now where your speakers have been!

Since I have no reference of what they sounded like before the upgrade, I cannot comment on the sound differences, but since the 100s are so old, I figured it could not hurt, and everyone seems to agree that a x-over upgrade is worthwhile.

redjr...

I agree. I hate those original posts they used along with those twist on terminals that AR's, Advents, etc used. I've changed those out every time I've done a recap so it makes it easier for swapping speakers around when/if I want to. Nice job on the crossovers, too. Ironic...I'm getting ready to recap a pair of HPM-100 crossovers today myself. This will be the second set of these crossovers I've done but these won't go on an actual pair of 100's since I had 2 pairs and one set was trashed. Half of the drivers were blown and the woofers were out. So, one day the cabinets may become something else. I figure I'll rebuild these crossovers and just sell them or do a swap out thing with someone who might be interested in them.

avguytx said:

I agree. I hate those original posts they used along with those twist on terminals that AR's, Advents, etc used. I've changed those out every time I've done a recap so it makes it easier for swapping speakers around when/if I want to. Nice job on the crossovers, too. Ironic...I'm getting ready to recap a pair of HPM-100 crossovers today myself. This will be the second set of these crossovers I've done but these won't go on an actual pair of 100's since I had 2 pairs and one set was trashed. Half of the drivers were blown and the woofers were out. So, one day the cabinets may become something else. I figure I'll rebuild these crossovers and just sell them or do a swap out thing with someone who might be interested in them.

Click to expand...

The boxes alone are worth keeping. I have to believe they could become newer, upgraded speakers with the right drivers and crossover. As you know, they're as heavy as lead. I'm sure there are thousands of pairs of 100's that someday could use a recapped x-over. Especially, if they're already modded and a simple plug-n-play.

redjr..

Just finished my recap a few minutes ago and now I just have to test them. Yep, I agree. Those cabinets are built really well and all it would involve is just a new front baffle to make most anything else fit in there given the right T/S parameters on the speakers. I thought about either doing a 10" or 12" woofer and some sort of horn in a 2-way setup...basically the Ewave design. Maybe one day....gotta finish up college first this fall. (and I'm 44 years old BTW...lol) I will have to reveneer the old cabinets too as they are quite dinged up but that's nothing major.