Sennheiser HD 650's thin sounding?

Just received a new pair of HD650's to replace my dead HD580's and they sound so thin!!!

I'm using a Headroom home headamp with a NAD 542 CD, Kimber PBJ's and stock HD650 cable.

What is the deal with these phones? My 580's had much more bottom end slam and bloom in the mid bass? Is it a burn in issue or defective phones? Anyone have a similar issue?
IMHO....Sounds like either a loose connection or a bad set of phones. I don't believe that they should sound "thin".
I've never owned the 650s but my 600s developed more fullness in the bass over time. Perhaps it is too early to definitively say the 650s are bass-light.

They will break in. However, I just replaced my 570's with AKG 701s and the difference is like moving from bose mini cubes to Thiels.
580 is way better than 570. It is pretty much the same thing as HD-600 with the same drivers. HD-600 is tuned a little bit better (position of the drivers).

HD650s deliver more bass than HD580 but needs 250-500hrs break-in time according to one review I read. HD-580 was one of the best bargains when Sennheiser discontinued it - I bought mine for $140.
Even new the 650 will not sound thin, and will produce more bass energy than the 580 or 600.
I having the same experience with my "near new" HD650. I don't believe it is a defective pair. When compared to my well-used HD600, the HD600 has more bass, more extended high, more air, and bigger sound stage - almost better in all areas. I hope the 250-500 hour break-in period is true, or I will be very disappointed.
I briefly owned the 650s but sold them cause I couldn't stand them. Moved up to the Denon AH-D7000 and haven't looked back.
Yeah...I had them for much longer than 500 hours. To be blunt - they are piece know. Even 50000 won't change them. Resolution is not bad but the rest of them is totally unacceptable. Cheapest Grado sound much better overall. Sorry.
Interesting posts.. I was beginning to think I was deaf.. my Senn 600's basically sound like c..ap. With the Musical Fidelity X Can they really are garbage compared to a decent system. I'm not sure if it is the X-Can or the combo, BUT they are so weak that i think any real listener has to be basically tone-deaf if they are recommending these 'cans as anywhere near hi-end! All those reviewers who think that these cans sound good should listen to my system and then tell me that. Pity as I think the Senn's are well made and they do feel nice to wear.
I have the HD 600s and find they are wonderful. I use the MG Head OTL headphone amp. For me they are better than any stereo system I have heard with more detail and nice weight and decent bass. I have more experience w. Speakers and Amps but it sounds like Headphones are similar in that they need to be matched to the amplifier driving them.

I have not tried any other headphones besides Grados for comparison. The Grados sounded great but very uncomfortable to wear long term for me.
I can not believe anyone would not be bowled over by the 650's. They have become better still after being played for some time, however, even new they were wonderful. I've heard them on OK components, and state of the art stuff, and although SOTA stuff sounded better, the 650's are always wonderful.
I have the 650's with antique sound lab otl headphone amp and card as cable and they sound absolutely fantastic.
There is something very wrong here, I have heard of HD650 copies getting around, also B stock from the factory, maybe yours could be one of these.
As mine are simply stunning to listen to. And the only headphone that I have heard to just slightly better them were the HD800's and not worth the extra double or tipple the price

Cheers George
Janeb, I had the X-CAN V3, and I found it to be totally underwhelming. Try a new headphone amp.
Here is a link to the fake HD650.

Cheers George
Spiritualized, I'm pretty sure that your'e right regarding the X-can. I noticed today that the latest version has been removed from the market. I have come to believe that all Musical Fidelity gear is nothing more than mid-fi at best.
Yesterday, I heard a pair of MF Titan's at a friends... they were a joke, my friend is taking them back as soon as he can. Overpriced total garbage as far as I could tell!
I agree that its unlikely that the 650s are the problem, unless of course they are counterfeit. I'd never describe my 650s as thin. Some might find them a bit laid back, but thin they are not. Never heard the X-can amp. Is there a possibility of an impedance mis-match btwn the can and the amp?
Grado PS1000s have far better resolving power and refinement.
I moved from the 650s to those. You will probably get significant improvement for the 650s from APS (A Pure Sound) or Zu 650-specific headphone cables (at least I did,
but the Grado PS1000s in stock form are in another league
to my ears). Check out the big headphone sites for this.