[noparanoia]

My thread about my wonky HD650s (1 new, 1 old driver) died. Seems most of you guys arn't that big on helping noobs so here is something that might actually be of interest to you.
 
A couple of hours ago I cranked up Sinegen to try a sweep of frequencies on my HD650s, and guess what? Tracking totally wonky all the way up the frequency curve. Nothing subtle here; running the slider up and down gives an effect that sounds like the deliberate panning effects you get in certain music.
This was not the case before I got the new driver, and it probably explains why they now sound like crêpe. Which is interesting.
 
The differences between the two drivers are that one is the old black type and the other is the new silver type. And one has thousands of hours while the other has around 3.
 
Which means that one (if not both) of these controversial and heavily disputed issues looks to be the cause . By creating this Frankenstein's Monster of a headphone (which incidentally is about as enjoyable to listen to as having ones face gnawed off by a badger) I feel I could be in a great situation to further investigate these phenomena.
However I know jack about this sort of thing, so if anyone is interested in this and does know a thing or two I will try my best to be as helpfull as possible.
I would even be willing to send my phones on loan (anywhere in the UK) because at the moment all they really do is sit on my desk inviting me to listen, which is always an immediately regrettable experience.
 
Urm, I starting to think this should probably be in the sound science forum, but I'll let the mods decide on that one.
 
Thanks

 

[kboe]

Interesting!  I believe in burn in because like you, I can hear it rather plainly.  What have you noticed when playing music?

 

[Uncle Erik]

This has nothing to do with burn-in.  I can't recall exactly, but there were reports awhile back that Sennheiser changed the type of driver used in the HD-650 and that there's a difference in sound between the old and new HD-650s.
 
Now, this is commonly done with headphones.  Sometimes, manufacturers tweak the drivers and don't announce them as a new model.  You'll find some heavy discussions about this for the R10, K-1000 and many others.
 
Also, there are significant variations in even identical drivers from the same factory and production runs.  No two are ever identical.  What manufacturers do is test each driver, record the results, then match up drivers that sound very similar to each other for the left and right channels.  The result is that you will have two pairs that sound slightly different.  That's not the result of "burn in" or cables or any of the mythological stuff.  It's because matched pairs of different values sound different.
 
What happened to you is that they stuck in a later production driver without matching it to the new one.  Send it back.

 

[wasp131]

I have the older "black" driver pair, and the newer "white driver" pair.
They do sound different from each other,the newer pair sound a fair bit brighter than the old darker sounding pair.
IMHO ,no amount of burn in will make them match each other and sound balanced.
best buy another "white" driver.

 

[ffdpmaggot]

I am a somewhat firm believer in burn in. For a while, I used vmoda bass freq headphones, every time they would break, I would get a new pair, and the first time I turned them on, they sounded colder than the last pair did. I would play music for about 2 hours, throughout that time, I found that they warmed up rather significantly. With my more expensive sets though, I feel that burn in is more psychological, my image S4 did not change at all, I heard nothing change in those, they maintained the same bright mids and fast, untextured bass with moderately shrill highs. The only improvement I noticed was when I pushed bass boost to color my mids a bit darker. Then we get to my superfi 4, I left them on playing the most bass heavy track I had overnight, and I noticed significant improvement in bass response which seemed a bit anemic to me at the time. Finally we have the E2c, which I've recognized as psychological burn in, the bass quantity changes based on how much attention I give it. If I focus on the bass, and think that they are a really bass heavy pair, they sound like "thumpers", if the track has very little other than vocals, they sound like "thumpers" if I get the thought into my mind that the response is anemic, it sounds anemic. In this aspect, i feel this may be what happened with my superfi, I thought they would sound heavier and they did.

 

[noparanoia]

hehe... I knew this would be a bit controversial

Thanks for the replies people.
I am also leaning towards the different driver hypothesis. I am going to bid for a pair of 5 year old HD650s on Ebay this week. If the drivers are good I will clip both of them into my nice new headband (that I had to pay £90 to replace the other day).
I knew this hobby would be expensive, but I wasnt expecting to have to pay around £200 in one month just in maintainance.
 
Anyhow, I am hoping that by getting some old drivers I will not only save myself some money but also be able to keep something close to the sound signature which I had grown to love.
 
Uncle Erik: Are you suggesting that the missmatch between drivers is a grounds for complaint? To be honest I am a little annoyed that a company like Sennheiser would do me a repair which is a "repair" in name only, if you get what I mean. Like the difference between saying "the unit functions" and "the unit is listenable", a distinction I hoped Senn of all people would understand.
 
 
wasp: Do you still listen to your wonky Senns, or have you got rid of them?
 edit - Scratch that, I thought you might be the other guy on this forum with an old/new HD650, but I was just reading what I wanted to see. Sorry!
Just out of interest do you find the sound loses anything from being brighter, or is it just "better in every way".
 
Thanks again peeps

 

[wasp131]

I dont think either is better,they are just different,
The older black drivers have a more seductive bass than the new ones,with greater depth to the soundstage,the lack of treble can make some genres sound rather flat and dull though.
newer white drivers have more zing in the treble and suit rock music more than the oldies, but treble can sound a little hard on some recordings.
I rarely listen to the 650's since i discovered the beyer dt990/600 which suit my musical tastes much better.

 

[bassophile]

wasp131, what do you mean by 'more seductive'...?
 
Does it hit harder, seem to extend deeper, and/or cover up more of the frequency spectrum? Or is there just more quantity?
 
Have you heard both 'versions'?

 

[wasp131]

Seductive!,
 
i found the bass on the oldies had more texture to it and seemed smoother and more detailed,but the treble seems to be rolled off earlier than the new version,
which may account for the smoother sound.
 
i found the bass on the newer version had a little more slam/kick to it but while sounding good seemed to have lost something in the bass detail but gained more treble energy which brightened the sound quite a bit over the oldies.
 
Its hard to put into words as you probably know ,
a friend of mine borrowed both pairs from me to try ,he has a slight tinnitus problem and he could'nt stand anything that had the slightest amount of simbilance in them.
needless to say he loved the oldies,the words he used to describe the new ones was "too sharp",he had no problems noticing the difference between the two either.

 

[Uncle Erik]

Yes, I absolutely think driver mismatch is grounds for a complaint. They were supposed to return them in functional condition and didn't. If anything, they should have sent you a reconditioned pair. Contact customer service and elevate the complaint. If they ignore you, contact one of the Sennheiser reps who occasionally come here. They should not want a Head-Fi member complaining about a botched repair publicly.

 

[noparanoia]

So Sennheiser do have a representative on this forum? I would love to be able to talk to them, and as I can just point them in the direction of my threads it will save a lot of hassle explaining my situation. When you say occasionally, how infrequently do you mean? Also I'm guessing that if they have accounts I can find their accounts regardless of their recent activity and PM them. Would a moderator be able to help me get in touch with one of these people?
 
Thanks

 

[noparanoia]

I agree with Wasp. Seductive is a lovely way to put it. The bass just draws you in and makes you feel so involved in the music. Of course I have only heard one ear of the new kind.