{"id":998,"date":"2017-11-04T22:56:18","date_gmt":"2017-11-04T21:56:18","guid":{"rendered":"http:\/\/storycase.co.uk\/radio\/?p=998"},"modified":"2024-05-09T20:48:12","modified_gmt":"2024-05-09T20:48:12","slug":"paradigm-pdr10-foam-rot-replacement-sub-woofer-fix","status":"publish","type":"post","link":"https:\/\/storycase.co.uk\/radio\/restoration\/paradigm-pdr10-foam-rot-replacement-sub-woofer-fix\/","title":{"rendered":"Paradigm PDR10 Foam Rot Replacement Sub Woofer Fix"},"content":{"rendered":"

Do you have a sub woofer with flapping distorted bass? Maybe the driver surround has torn with the dreaded foam rot? If so don’t throw it away, replacing the sub woofer speaker drive unit takes less than an hour and revives the deep clear rumble for around \u00a330- \u00a350.<\/p>\n

Warning: Never<\/strong> operate you sub-woofer with the amplifier removed – there are exposed mains voltage connectors inside and the amplifier has a heavy transformer that can topple over!<\/em><\/p><\/blockquote>\n

I blame Star Wars Rogue One on the demise of my budget Paradigm PDR10 which I rescued in a previous post. By the end of the movie the woofer sounded awful with a flapping sound at even modest volume. As you can see the fault was the speaker driver where the foam surround had split.<\/p>\n

\"Parading<\/a>

Parading PDR 10 Driver Foam Rot Fault<\/p><\/div>\n

It’s possible to buy replacement surrounds for a few pounds and re-foam the speaker. But a gentle push on the cone centre revealed a rasp sound as the voice coil touched the magnet. It would be tricky to centre a new surround and the coil may be damaged due to surround failure.<\/p>\n

To access the speaker you need to remove the 12 black screws that hold the rear amplifier panel in place – remove power cable first – see warning above. Don’t be tempted to try and take the front grille off as it’s glued in place \u2013 all servicing is done via the cutout in the rear. If your sub rattles or vibrates it could be the front panel glue has failed – see Paradigm PDR10 Rattle and Hum Faults<\/a>\u00a0detailing a fix for that.<\/p>\n

My PDR10 had a 10 inch Paradigm speaker with a label – Made in Canada, Part number B156WPDR1000S. No details on impedance or power handling. So I used a multimeter and found the speaker measured a DC resistance of 3.8 ohms. Choosing a replacement from the myriad of sub-woofers out there was a challenge. I began by looking at car sub woofers as these have 4\u03a9 impedance or 2 + 2\u03a9. However, most car subs seem to be designed for style and not suitable for front mounting in the PDR10. They also tend to resonate around 35 – 40Hz and have very high power ratings not required for the PDR10 which kicks out 100w.<\/p>\n

So in the end I chose an 8 ohm hifi quality Fenton Audio driver that cost just over \u00a330 from Electromarket<\/a>. (Update: Similar part available under Skytec brand same model number:\u00a0902.214 – Product code CCA0138) Being 8\u03a9 it would probably not offer the peak power the 4\u03a9 original but has an extended low frequency response down to 25Hz.<\/p>\n\n\t\t