Can the sound of 'phones deteriorate over the years?

Sorry I meant HD580s...simple typo + the usual problem of not being able to edit your opening post, which continues to be a right royal PITA!

Very unlikely a 580 would deteriorate unless you see obvious signs on the exterior. New earpads will make a difference. If there were deterioration in the sound due to something electronic, magnetic, cables etc., you would almost certainly hear it more on one side than the other.

BTW - pull the cable tips out of the earcups right now and wipe them off, and blow into where the cable tips were to dislodge any crud, them plug them back in. That often fixes it.

I've cleaned the connections and it doesn't seem to have made any difference.  No matter what I plug them into the they sound far too mid-range heavy with little bass to speak of.

I'm tempted by new pads as I can't afford a set of new decent phones right now, but even they're £40 a pair from Senn and currently £40 is a lot of money for me to waste if they make jack-all difference.  It's times like this you need a try-before-you-buy

Another thought is to find someone with a 500/600 series Sennheiser and just swap the cables for a moment. If that does not change anything, and the deterioration seems to be the same on the left and right both, I would not suspect anything in the earcups or the left-right cabling, since one would not deteriorate the same as the other - very unlikely. So that would leave the earpads?

It's difficult to know whether to shell-out £40 for replacement earpads in the hope they improve the sound or start a MajorFubar's New Headphone Fund with a £40 start, with the intention of eventually buying something new which would better the 580s to start with.

Things have changed a lot in the headphone world since I bought my HD580. I subsequently bought a 600, 650, 800 and a few others, but I'm currently sitting on 3 main headphones now: Shure 1840, Philips L1, and ATH M50. The Shure has a small advantage over the Philips in the upper end, but loses big to the Philips in the low end if the Philips is EQ'd. Without EQ the Philips is not a contender. So if you don't mind a closed headphone and slightly narrower soundstage, the EQ'd Philips beats the Shure by a mile. The M50 beats the EQ'd Philips by a small margin in the bass, but loses in the mids and highs, so I'm inclined to give the EQ'd Philips a small advantage over the M50 overall, but with 2 notes: One is that the Philips costs almost twice as much, and two is that the Philips has to be EQ'd to compare to the M50.

Comparing the Shure to the M50, the Shure is significantly better in the mids and highs, but the lack of bass is enough to make a person cry, once you get used to the M50 for example.

So how does all of that compare to the HD580 or 600/650? The HD580 is somewhat veiled and distant, so I was happy to get the 600 to replace it. But while I think the 600 and possibly the 650 (and certainly the 800) are closer to the generally accepted "neutral" sound than the 3 headphones I have now, I would still prefer any of the ones I have now to the 600 and 650, although the 800 would be the one to beat for ultimate sound quality.

Do you think that as you say " over the years " that maybe your hearing has changed, just  a thought..............

Worn pads reduce the amount of bass as they don't seal like they are supposed to.

I think I'll need to save up a few pennies and go and audition some new cans.  But it'll be a while yet; I've got more commitments now than back in the day when I shelled-out £200 on a pair of headphones without thinking twice about it, and back then £200 is more like £250+ now.

There is a myth about "Age-related hearing loss", which falls into the same genre of myth that says MD's are Health practitioners.

Hearing loss is strictly health related, which in turn is *usually* age related, so you can figure out the rest. Or maybe not.

My vintage headphone collection varies from sounding superb to OK and I am sure there is a correlation between condition and sound. I also experienced a bit of burn in, which I was surprised at as some of the cans were 30 odd years old. But it appears the diaphram does flex to a slightly new state and will relax again back to its original state if left unused for a time. That was found with ICE and cinema speakers, so I am only theorising it also happens with the much smaller headphone speaker. Maybe you have exerienced the same?

I was never that impressed with the HD580s and would suggest the money is the fund for your next cans.

Some headphones and speakers will not deteriorate sound-wise, but you might have to do a lot of searching to find out which ones and why. One example - the Beyer DT-48 series - they will not deteriorate unless the environment they sit in is hazardous to humans. Some headphones have components glued together and the glue may disintegrate over long periods of time. I would not expect a Sennheiser 500/600 series headphone to deteriorate after 20 years unless it got mold or moisture or something like that inside.

The B&O U70 is notorious for its foam earpads falling to bits. I can see how that would affect the sound.