http://www.moon-audio.com/headphones/sennheiser-headphones/sennheiser-hd-700.html   You can preorder them through Drew Baird.

I think they are. But they are single so you need 2 per on an adapter.

I'm using the 650's with the xonar essence stx also. If you really want to give your card a boost you should replace the op-amps with 3 of these. http://www.ebay.com/itm/DUAL-SOIC-LME49990-DIP8-ADAPTER-/190641930863?pt=LH_DefaultDomain_0&hash=item2c6325026f#ht_1039wt_1396  or 3 of these...

I think the screeching noise maybe due to the videocards audio drivers. Just don't install those drivers, it gives you a choice. I have windows 7  64 bit and have never had a single problem.   i7 3930K Asus P9X79 Pro Corsair 32gb (4x8gb) Corsair 1200w psu EVGA GTX 580 Classified

Upgrade the op-amps to LME49990's. You can get them on the adapters on ebay. 2x each adapter. It is amazing, trust me.

After upgrading my op-amps to the LME49990's, Techno Rave from Blade is awesome now.

I just now read some of the things in this thread. I have a friend who bought the crappy Beats. He asked me the same thing until he listened to mine and he wants his money back.

You will need 2 per adapter, which is six total 49990's. Trust me, they are only half the size of the dual's, its better to buy them already done, and the guy that built them did an excellent job soldering them, its well worth it.

It needs an adaptor, its a single soic when the card takes dual's. The cheapest way to get them is through the ebay link I posted. Or just buy an adapter and the 49990's and solder them yourself. They are tiny though and my hands shake, too scared to do it myself.

Okay, I installed the 3 sets of the LME49990. My verdict is its UNDENIABLY THE BEST OP-AMPS EVER! The bass is amped up to new heights, but the music is even more clear. The detail is amazing. Only thing is DO NOT USE THE SAME VOLUME LEVELS YOU ARE USED TO. If you do it will blast your ears off...

It has to be the stupid power saving features built into windows 7, sometimes it provides way too much power to the pci-e slots. Just turn that off and it should never happen.

I just ordered 3 of these, when I test them out I'll let you all know how they perform.   http://www.ebay.com/itm/190629659561?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649#ht_1039wt_1396

Here's how mine is setup and it has no noise. Under Control Panel- Hardware and sound- Playback: Asus Xonar Essence-Default Device. S/PDIF: Same. Under sounds it is the Windows Default. Also check your cables inside your comp. You could have the Realtek front panel audio cable hooked up to the...

I also have an upgraded cable, that'll probably make a difference in the audio with these settings too.

I have mine turned off, I think it makes it sound terrible. I have my settings on 8 channel, PCM 192 khz, effect is Padded Cell- S-Rock, Flex Bass is 150hz, HP Large. With these settings and upgraded op-amps on the 650's music sounds amazing.

Oh, I just found the brown dog adapters that involves no soldering what-so-ever. But they charge $33 for 2 of the op-amps. I'll just buy those seperately.

Where would I get the adapters to use the 49990's? I seen where I can buy the op amps at $2 a...

Are there any op-amps that have come out within the last year that are better than 2x LME49860?

I am definitely buying these in March.

Here is my settings I have under the Xonar Audio Center that I think sound the best.   Audio channel- 8 channels Sample Rate- PCM 192 khz Analog Out- Headphone SPDIF Out- Check on headphone   EQ mode- Soft Rock LFE crossover mode- 250 hz HP- Large Environment- Padded Cell...

IMO, best buy has horrible prices for everything. Amazon on the other hand has excellent prices, especially on headphones.

I can't really use speakers the way I want cause I live a couple blocks from the police station. But I'm perfectly happy with my HD650's with Blue Dragon V3 cable through my xonar essence stx with upgraded op-amps. Its as close to life like that I can afford.

I listen to alot of heavy metal, some hip-hop, and some classical type(mostly from Hans Zimmer). I just think the 650 does a better job at producing a more realistic sound and it does it without all that popping that the whole 500 series had, which is very annoying.

Wow, and I upgraded to the HD650's from the 598. I think the 650 is leaps and bounds better than the 598.

First off, the only sources I listen to anything through are my receiver while watching a movie or playing a game on my ps3 or my computer which I have my headphones hooked directly to my asus xonar essence stx card. What would be a good headphone amp that I can use? I know pretty much nothing...