My HPM -100/100W restoration project.

I picked up these HPM-100's this weekend that were very badly neglected and in need of some CPR to bring them back around. One speaker was missing the Mid Range and of course all the dust caps to the wide range woofers, Mid range and tweeters had the push button syndrome inflicted on the dust caps.
I have disassembled the speakers, which included removing the crossovers, L-PADS's and badges from the cabinets. While doing this; I learned that my purchase of these HPM's may have made a family of Rodents homeless as you will see from the pictures. I have the hopes and intentions to re-laminate the cabinets with some new Veneer and to replace the one Mid range with another factory Pioneer for this model.
I have been looking at Van Dykes website and they have some killer Quarter Sawn African Mahogany I think would put some killer looks on the cabinets. Or, should I stick with Walnut veneer?
I am going to have to pitch the Cabinet insulation in the garbage due to the Rodents who homesteaded in the cabinets and the odor they left behind. So, I am wondering if there is some now better than original cabinet insulation that can be used to replace it. I thought about going with Memory foam inside the cabinet's as sound insulation. The Memory foam I have is about 2 inches thick and of course pretty dense. Has anyone ever used this before in a set of speakers or has any suggestions as to what I should use as to not destroy or make the base to dead sounding? Then, Is this project even worth doing or, should I just part the speakers up and look for some better cabinets? Any suggestions, tips or advice for these HPM's will be greatly appreciated. Thanks!
 

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Rebuild and refinish them, they are worthy speakers though i may be a “little” biased. I’ve redone 3 pair and had a lot of fun doing it! They have a sound, for sure, they mate up well to the higher powered SX series Pioneer receivers, my 950 makes them positively SING.
 
Looks like a fun project to me.

The veneer choice is up to you. I'm partial to mahogany, but do what pleases you.

I would avoid using the memory foam in your cabinets. Memory foam will likely kill the bass response because it is too dense and may be closed cell, depending on the type. There are reasons that the manufacturers/designers use very loose, open fiber stuffing. (Along with a few noted exceptions.) It does not take up volume in the cabinet (in fact, it makes the volume larger), and it allows the free flow of air within the cabinet while at the same time deflecting the rear waves of the woofer so that they do not become bass-killing out-of-phase reflections. FiberFill or fiberglass does the job perfectly. (There are hundreds upon hundreds of studies on this issue if you want to do further reading.)

Keep us updated on your progress. The HPM100 is a popular speaker, and your rebuild will help those that take the same route later.

GeeDeeEmm
 
I would love to see how you restore these beauties in the event you go to restoration route. Mine is in much better shape compared to yours, my goal is to restore mine to the original with possible added protection from scratches, though I am afraid to ruin it as I have limited experience in wood working and varnishing, I do not know what type of materials to get, sequence etc.
Good luck!
 
Sorry I have not posted any updates. I am in the middle of moving and everything has been put on hold on the HPM 100's. I did try to do the wood on wood Veneer before I had to set it to the side and it did not turn out so well. I will try to post pics of it this weekend.
 
Sorry to hear it didn't turn out so well. I just veneered a set of old BIC speakers and I started out using the PVA iron method and I ruined all the veneer because it just wouldn't stick so I went with the contact cement method that I'm familiar with and had much better results. Do keep us posted when you have time.

GT
 
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