But why waste time on a forty year old piece of electronics? Surely modern headphones are much better and only a click of a mouse away? Well, maybe, but I love the sound of these old phones and they are so light on my head I can wear them for hours - even with glasses.
So what was wrong with them? The foam earpads had perished and had literally gone to pieces inside the cloth covers and the headphones were becoming uncomfortable to wear. I tried looking on Sennheiser's web site - and their support site - for replacement pads, but it appears that you cannot get hold of them any more. Such a pity.
There are other HD420 owners on the Internet also seeking replacement earpads so I thought I'd see what else I could do - and hope that my findings are of use to others.
The Sennheiser HD420 earpieces come in three parts. There's the transducer in its plastic housing, an acoustic foam insert and a cloth cover that holds the foam to the transducer. As long as the cloth cover is intact and the headphones work, then all you have to do is replace the pads.
- First measure the earpiece diameter (they are 80mm)
- Next search Amazon for "80mm replacement earpads"
- Buy one of the items that come up in the results
When they arrive you have to replace them. This needs patience, fingers, kitchen paper and an old toothbrush. No other tools or you risk damaging the cloth cover or the headphones.
First you must tease off the cloth covers. Use your thumbnail and carefully ease the plastic surround all round before gently sliding the surround off the transducer.
Here you see the new earpad with one of the cloth covers
Finally the restored Sennheisers, all padded out and once again, fit and ready to listen to.
Total cost? less than £3.00 and under thirty minutes. Satisfaction? Priceless. :)