Restoring JBL Paragon

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04-08-2014, 05:19 AM
murdoch

Restoring JBL Paragon

Hello all, I am thinking of restoring my dad's paragon and I need advise on what to do to have the drivers and the dividing networks restored.

I have fired it up and the 375's seem to be spot on but the right side 075 ring radiator seems weak and had been intermittently cutting off.

I also want to have the dividing network components checked.

Will someone be kind enough to direct me to people who are truly knowledgeable in this kind of restoration? Also perhaps to help me how to do the restoration in general via email as I live in in southeast Asia.

Eventually, I will need help to source the correct size and type of wires needed to replace the old ones too.

This is also very sentimental to me as this is how I have bonded with my dad. It brings wonderful and poignant memories of our times listening to music together and I must confess that I love it dearly. Both the memories and these speakers which bring it all to life again. Paragons, being the heirlooms that they are would be one that I will pass on to my only son too.

Thank you all and I do hope that help will come.
04-08-2014, 06:13 AM
BMWCCA

Quote:

Originally Posted by murdoch

I have fired it up and the 375's seem to be spot on but the right side 075 ring radiator seems weak and had been intermittently cutting off.

I would check the rotary control (L-pad) on the N7000 crossover. It's likely the source of your intermittent behavior on the 075. The simplest first step is to rotate the control from one extreme to the next several (many) times with the system off (or volume turned down) to see if that's enough to clean the contacts. If that works, you're good to go. Otherwise the N7000 is actually a very simple network and there are many threads here about replacing caps as well as cleaning the L-pad.
04-08-2014, 01:28 PM
audiomagnate

Quote:

Originally Posted by BMWCCA

I would check the rotary control (L-pad) on the N7000 crossover. It's likely the source of your intermittent behavior on the 075. The simplest first step is to rotate the control from one extreme to the next several (many) times with the system off (or volume turned down) to see if that's enough to clean the contacts. If that works, you're good to go. Otherwise the N7000 is actually a very simple network and there are many threads here about replacing caps as well as cleaning the L-pad.

I'm friends with an ex-Harman employee who is also a hell of a tech, and he told me the caps in those crossovers should last a very long time. It sounds like you have, except for a dirty pot, a fully functioning Paragon. The tweeter pots do sometimes go bad - I've seen one that literally fell apart - but the old trick suggested above may be all you need. If you want to do it right get some Deoxit and Fader Lube. Like my dad used to say, if it ain't broke, don't fix it!
04-08-2014, 05:10 PM
SEAWOLF97

Quote:

Originally Posted by audiomagnate

Like my dad used to say, if it ain't broke, don't fix it!

Like we used to say at Intel , if it ain't broke, fix it 'till it is ..... :blink:
04-08-2014, 05:13 PM
Mr. Widget

I agree with the previous posters that the likely culprit on the 075 is your L-pad. If your Paragons have LE15A woofers, I would pull your woofers though and inspect the surrounds. It is very likely they have the old Lans-a-loy material which gets very stiff over time. Replacing these surrounds with modern foam will improve the bass significantly.

It is possible that your Paragon has the 150-4C woofers... if they are installed, then you are good to go. That said, these are very rare. It is much more likely that you have the LE15A woofers.

Widget
04-09-2014, 01:13 AM
murdoch

Quote:

Originally Posted by BMWCCA

I would check the rotary control (L-pad) on the N7000 crossover. It's likely the source of your intermittent behavior on the 075. The simplest first step is to rotate the control from one extreme to the next several (many) times with the system off (or volume turned down) to see if that's enough to clean the contacts. If that works, you're good to go. Otherwise the N7000 is actually a very simple network and there are many threads here about replacing caps as well as cleaning the L-pad.

Thank you sir for that quick tip. I'll try to do all the generous and sound advise you have given me over the weekend. I think you are right about the caps and I hope that's just it. I can't wait to do a thorough check on it. Again, my thanks.

I see your name as BMWCCA, I surmise you are a BMW enthusiast? Great marque.
04-09-2014, 01:16 AM
murdoch

Quote:

Originally Posted by Mr. Widget

I agree with the previous posters that the likely culprit on the 075 is your L-pad. If your Paragons have LE15A woofers, I would pull your woofers though and inspect the surrounds. It is very likely they have the old Lans-a-loy material which gets very stiff over time. Replacing these surrounds with modern foam will improve the bass significantly.

It is possible that your Paragon has the 150-4C woofers... if they are installed, then you are good to go. That said, these are very rare. It is much more likely that you have the LE15A woofers.

Widget

Thank you very much Mr. Widget. I'll have to check if I have the LE15-A or 150-4C woofers on it. But if my memory serves me right, the Paragon being a circa 1969 model, might have 150-4C's. I'll let you know for further advise. Thanks again sir.
04-09-2014, 01:25 AM
murdoch

Quote:

Originally Posted by audiomagnate

I'm friends with an ex-Harman employee who is also a hell of a tech, and he told me the caps in those crossovers should last a very long time. It sounds like you have, except for a dirty pot, a fully functioning Paragon. The tweeter pots do sometimes go bad - I've seen one that literally fell apart - but the old trick suggested above may be all you need. If you want to do it right get some Deoxit and Fader Lube. Like my dad used to say, if it ain't broke, don't fix it!

Keeping my fingers crossed that it will be just dirty caps. It's been 5 years since I last fired it. Couldn't get myself to really get into it as I intended to restore it ground up and that is a big project. I just want to be sure that it's checked well before I do.

Thanks very much Mr. Audiomagnate and i'll give you fine gents an update and some pics next time.
04-09-2014, 01:30 AM
murdoch

Quote:

Originally Posted by SEAWOLF97

Like we used to say at Intel , if it ain't broke, fix it 'till it is ..... :blink:

Thanks Seawolf. I agree but I don't think that goes with the interconnect wires between the drivers and the networks. The wires are at least 45 years old :D. I decided to use some newer wires for temporary use until I get advise about the right size, type and brand wires that I may be able to pick up from here.

Till then, wish me luck sir.
04-09-2014, 06:13 AM
audiomagnate

Quote:

Originally Posted by murdoch

Keeping my fingers crossed that it will be just dirty caps. It's been 5 years since I last fired it. Couldn't get myself to really get into it as I intended to restore it ground up and that is a big project. I just want to be sure that it's checked well before I do.

Thanks very much Mr. Audiomagnate and i'll give you fine gents an update and some pics next time.

Dirty potentiometers (L Pads), NOT dirty caps. The caps may be fine.

Quote:

Originally Posted by murdoch

Thanks Seawolf. I agree but I don't think that goes with the interconnect wires between the drivers and the networks. The wires are at least 45 years old :D. I decided to use some newer wires for temporary use until I get advise about the right size, type and brand wires that I may be able to pick up from here.

Till then, wish me luck sir.

Wire really doesn't go bad. If the insulation rots then it should be replaced, but if it's intact, KEEP IT ORIGINAL. Collectors prefer these things in original condition. The fact that yours seems to be very close to original WORKING condition is a big plus. I hope you saved the old wire, but if you didn't, generic 16 awg color coded speaker hookup wire will do fine. I know you're not in the US, but here is what I use, unless someone wants to pay extra for "magic" wire. http://www.parts-express.com/Search....itesearch=true
04-10-2014, 02:16 AM
murdoch

Quote:

Originally Posted by audiomagnate

Dirty potentiometers (L Pads), NOT dirty caps. The caps may be fine.

Wire really doesn't go bad. If the insulation rots then it should be replaced, but if it's intact, KEEP IT ORIGINAL. Collectors prefer these things in original condition. The fact that yours seems to be very close to original WORKING condition is a big plus. I hope you saved the old wire, but if you didn't, generic 16 awg color coded speaker hookup wire will do fine. I know you're not in the US, but here is what I use, unless someone wants to pay extra for "magic" wire. http://www.parts-express.com/Search....itesearch=true

Oops....yup potentiometers not caps. Corrected sir. Thanks again.