High end Sennheisers timely warning!

Hi People,

I have a pair of Sennheiser HD580 headphones which have developed a fault in the cable or right ear piece. I rang technical support at Sennheiser UK for a replacement or repair and in the course of this call I picked up some information, which other users of these excellent 'phones (also the HD600 and HD650) might wish to bear in mind. So I pass it on here.

Do not switch on your system with these 'phones connected to it. Apparently many systems give a power surge at startup that can melt the copper or alumunium parts in the 'phones. This can happen in a single surge or as a result of leaving the 'phones plugged in, thus giving them repeated jolts and causing the damage.

I'm a little disappointed that my 'phones failed after only a few days use and don't think that the above is the cause of my problem. I'm returning them (purchased in Germany a couple of weeks ago) to Sennheiser UK and am impatient for them to be returned as they are terrific phones.

Leporello

[alexs2]

Many thanks for that very useful bit of info....there are a good number of us here using Sennheisers,so I'm sure everyone will be very grateful for that.

[mattross]

I think Sennheiser might be making excuses. In the past there have been quite a lot of problems with the connectors on various models. I know this because I have a pair of Ovation 565s with the standard cable and the connection is not great, sometimes when I turn my head [wearing them of course!] I lose the signal in one side.

Don't have the problem with my 650s, but then I don't use the standard cable on them!

[alexs2]

That's also a possibility,and one I couldn't confirm either,using a valved headphone amp here,with a very slow startup.

Originally Posted by mattross

I think Sennheiser might be making excuses. In the past there have been quite a lot of problems with the connectors on various models. I know this because I have a pair of Ovation 565s with the standard cable and the connection is not great, sometimes when I turn my head [wearing them of course!] I lose the signal in one side.

Don't have the problem with my 650s, but then I don't use the standard cable on them!

I don't think anyone at Sennheiser was making any excuses. The people I spoke to listened carefully to me. The matter of the power surge was raised during a longer conversation. I was happy to be heard and happy to be 'phoned back promptly as promised.

By all means remain sceptical or assume the worst about Sennheiser, but I'll bear this warning in mind rather than dismiss it out of hand and risk burning out some expensive cans.

Others reading this thread will make their own minds up. So there!

Leporello

[pbirkett]

Some headphone amps warn STRONGLY against not having headphones plugged in at startup... :D

[x-pro]

Originally Posted by Leporello

Do not switch on your system with these 'phones connected to it. Apparently many systems give a power surge at startup that can melt the copper or alumunium parts in the 'phones. This can happen in a single surge or as a result of leaving the 'phones plugged in, thus giving them repeated jolts and causing the damage.

There is one simple way to tell - if there is a problem, you will hear it as a loud sound (click, boom or whatever) on a switch-on. Well-designed headphone amps will give either very little or no sound at all on startup. I've so far never heard of a headphone blown up by a dedicated headphone amplifier. Integrated amps, receivers etc. - a completely different matter. Some of these could produce a lot of voltage on a headphone output, especially on high-impedance headphones. Safe maximum voltage on Sennheisers 300 Ohm phones, i.e. HD565, 580, 600, 650 is about 5V RMS (that is for the phones, not for your ears!) . There is at least some possibility that a switch-on voltage jump (or a full volume output) of a powerful amplifer can go over this limit.

So the conclusion is - if you use a decent headphone amp, don't worry, keep your phones plugged in. If you use a high-powered integrated amp, receiver etc. to drive your headphones - take care, especially if there is a loud sound in the headphones when you power up the amp.

Alex

[pbirkett]

Eh? Why should an integrated amp or receiver be potentially more damaging? You do know there is resistors in its path dont you? I fail to see where this extra danger you speak of is, unless you have your cans connected to the speaker outputs, in which case I'm not surprised.

[x-pro]

Originally Posted by pbirkett

Eh? Why should an integrated amp or receiver be potentially more damaging? You do know there is resistors in its path dont you? I fail to see where this extra danger you speak of is, unless you have your cans connected to the speaker outputs, in which case I'm not surprised.

Mostly because these can produce a lot of voltage. Common value of resistors on a headphone output is 330 to 470 Ohm. If the amplifier rated 50W into 8 Ohm it can produce at least 20V RMS (probably more into light load) and the voltage across 300 Ohm headphones could easily reach dangerous for Sennheisers levels .

Alex

if you use a decent headphone amp, don't worry, keep your phones plugged in.
Alex[/QUOTE]

Well that's very reassuring to know Alex. Now where might I obtain a decent headphone amp in Crouch End on a cold Thursday evening? :smashin

Leporello

[x-pro]

Originally Posted by Leporello

Well that's very reassuring to know Alex. Now where might I obtain a decent headphone amp in Crouch End on a cold Thursday evening? :smashin
Leporello

Perhaps it is easier to get on a cold Wednesday evening?



Alex

[StevieDvd]

I'm sure you can buy one in Enfield ;-) I got mine at 7pm Kings Cross in the coffee shop, honest!

PS Welcome to avforums Alex.

Originally Posted by x-pro

Perhaps it is easier to get on a cold Wednesday evening?



Alex

Perhaps I should have explained that it is/was Thursday to me. I can't really be held responsible for the fact that everyone else starts a day ahead of me. I spoke to my Guru about this and he reassures me that everyone else is out of step.

Incidentally, I'm listening to some music via the amp right now. You would'nt believe just how good Des O'Connor's Golden Hits sound now.

[QUOTE=StevieDvd] got mine at 7pm Kings Cross in the coffee shop, honest!

QUOTE]

It wasn't from a Russian guy with a beard by any chance?

[pp312]

Originally Posted by Leporello

Hi People,

I have a pair of Sennheiser HD580 headphones which have developed a fault in the cable or right ear piece. I rang technical support at Sennheiser UK for a replacement or repair and in the course of this call I picked up some information, which other users of these excellent 'phones (also the HD600 and HD650) might wish to bear in mind. So I pass it on here.

Do not switch on your system with these 'phones connected to it. Apparently many systems give a power surge at startup that can melt the copper or alumunium parts in the 'phones. This can happen in a single surge or as a result of leaving the 'phones plugged in, thus giving them repeated jolts and causing the damage.

Sorry to say this but I think Sennheiser are feeding you . The 580 (+ 545, 565, 600) has a long history of connector problems, which Sennheiser has notoriously been in denial about. Apart from fitting a (permanent)replacement cable the only solution is to coat the connectors with a contact enhancer like Caig Pro-Gold. This needs to be done every few months.
As for surges in systems--crap. I've always left my phones plugged in and never had a problem, nor have I ever heard of anyone else having a problem. Think about it. If amps were liable to blow plugged-in phones at switch on, there'd have been a huge scandal about it years ago. Frankly, it doesn't happen unless the amp is faulty and/or the protection resistor has gone AWOL. No, this is definitely just the latest chapter in Sennheiser's long history of denial, and it's time they started to feel ashamed.