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Pioneer spkrs HPM-100: Restoration

R

Radni

New Member
I am trying to restore my HPM-100 and being first timer DIY er , would sure appreciate help from members here. I will have a local technician to help me with replacement job.
I wish to change or upgrade caps, resistors , binding posts,
internal wiring, add Deflex elastopolymer panels .
My spkrs are 200 watts , so type C crossover of HPM-100.
I read on crossover the following values on caps and resistors:
Capacitors : 4.4 K 100 V , 3 K 100 V , 0.15 uFD 63 V ,
Resistor : 10 ohm 5 watts

I do not know how to convert K into uFD . So what value of uFD
caps I should buy ?
The coils and resistor look like new , no aging . So may even drop the idea to change resistor.
Original binding posts are rather poor quality, so wish to change but I do not
know which ones will fit in .
Help , suggestions will be appreciated.
 
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If I were rebuilding my HPM100's I would change the capacitors, I have used Solens in other speakers. There are lots of different brands to choose from. Parts Express has lots to choose from.

I would replace the resistor if it were out of spec. As for the rest of the crossover parts, I woudl leave them original.
 
elnaldo said:
Welcome to AK !!


K is the tollerance (10%) and 4.4 is 4.4uF , and 3 is 3uF. I don't own a pair, but you can download this service manual, Iḿ sure all the data is in there

http://akdatabase.com/AKview/albums/userpics/10004/Pioneer HPM100 Service.pdf
Click to expand...

Thanks a lot , elnaldo and ChrisMarantz for Your help and service manual .
I am in process of ordering parts on PartsExpress.
I am replacing caps , Resisitors, adding damping material, changing binding posts.
Though I do not know what binding posts will fit here. Any idea you have ?
Can you help me to select right Tweeter as a replacement ? My budget will be $ 30 to 70 each .
 
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About the binding posts, you could do a search here in AK for another restoration. The HPM100 is a very very famous speaker, I'm sure you'll find some answer to your questions, including the tweeter replacement.

BTW what's wrong with your tweeter? Are you sure it's not working and need to be replaced? Usually, repairing and keeping the original is the best option.. Or, perhaps is just a crossover issue. Don't forget to clean the pots with contact cleaner, perhaps is just a dirty pot.

Adding or substracting damping material can change the sound, for better or for worse, so do some testing or read about other people that did the same.
 
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One of the tweeters is giving scratchy sound ( but not too bad ,really !) , not so clear as the other one.
But I do agree with you to take caution and go slow on tweeter replacement. The tweeters on my HPM-100 look fine on inspection but the one that is little bad is having its central cap like melted and pushed in. Is that a problem ? I do not know.
So I will not replace them for now , and also may not add damping material ( I was thinking to add two panels of Spectra Dynamic Deflex in each speaker. What is your comment to that ? ) .
Binding posts are showing aging due to weathering and I really wish I can find replacement.
For the time being in my project I will replace Caps, resistors, internal wires , clean the pots with contact cleaner.
I find on ebay several tweeters for HPM-100, so now I know I can replace them in future only and only if need to . Otherwise originals are not too bad at all ! But now I am convinced that I must have the original drivers on my HPM-100 and not to tweak by replacing with other type or brand . Thanks for giving me the insight to stick to original character of the vintage ( to the extent possible ) to keep enjoying them.
Thanks for your interest and help.
 
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You could replace all the crossover components on a separate board, all with better components, even the inductors. You could drill two additional holes in the back for real, large diameter accepting binding posts. It would look completely original except for two additional binding posts. There is a thread in here somewhere where this was done. It is what I would do if I were in your shoes. It's going overboard a little, but fun and satisfying to do sometimes. My 0.02.
 
ChrisMarantz said:
If I were rebuilding my HPM100's I would change the capacitors, I have used Solens in other speakers. There are lots of different brands to choose from. Parts Express has lots to choose from.

I would replace the resistor if it were out of spec. As for the rest of the crossover parts, I woudl leave them original.
Click to expand...

Thanks . I decided to replace all three caps and the resistor and binding posts.
I chose Solen MKP FC for 4.3 and 3.0 uf caps , and Jantzen Z-silver for .15 uf , mills resistor . In caps l had option of Dayton also , but I chose Solen .
I also changed internal wires , I noticed the old ones were very thin and looked ordinary. I replaced them with Van Den Hul Skytrack 16 Gage OFC Halogen free wires .
I am finished replacing parts on one speaker.
 
No question. I have two pair, one recapped, one not, and the recapped pair definitely sounds better. I need to get around to doing the second pair.
 
Riley212 said:
http://audiokarma.org/forums/showthread.php?t=120454
but you are probably done wit this part by now i hope
Click to expand...

It is a great thread for anyone doing upgrades on xover of HPM-100 . I did not hit that thread earlier , otherwise it would have been much easier for me to do the job .
I noticed one thing : mostly no one changed the internal wires , and only few opted to change the binding posts. I find personally both these replacement worthwile its cost and effort.
 
Gibsonian said:
You could replace all the crossover components on a separate board, all with better components, even the inductors. You could drill two additional holes in the back for real, large diameter accepting binding posts. It would look completely original except for two additional binding posts. There is a thread in here somewhere where this was done. It is what I would do if I were in your shoes. It's going overboard a little, but fun and satisfying to do sometimes. My 0.02.
Click to expand...

Being first time DIYer , I wanted to limit my ambitions to match my skills , besides the coils looked very much like new . I did replace internal wires with VDH skytrack OFC halogen free wires and Binding posts ( Dayton ) as the larger ones were difficult to accommodate.
 
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