Would I hear the differance with my setup (HD650s vs HD700/800)

You would certainly hear the difference in sound because they sound completely different. This may be obvious, but only you can decide if you prefer the warmer full-bodied tone of the HD650 to the brighter and unforgivably revealing sound of the HD800 (and I assume HD700). Not that many people that I know own both. They prefer either one sound or the other.

I highly doubt your setup will really push the HD700/800 anywhere near to its performing limits, but the differences would still be plain as day.

Get a HA-160D for that money and you will have a much better improvement in sound that expensive headphones off gear that won't do well with them.

I would get an Amp and DAC or DAC/Amp. After you've heard how your 650's can sound then consider new phones.

I agree that you would be better off with improving your HD650's from a price/performance standpoint. The HD800 is a technical juggernaut, but the HD650 used to be a flagship too and can hold its own in the arena. It scales extremely well and is one of the best deals when you consider its performance capabilities. Most people would only recommend the HD800 on very high-end setups and that is more than probably you (and definitely I) would be willing to pay.

Summation: No, the HD800's (not sure about the 700's) are not worth the cost if you are not willing to shell out for equipment to bring them to the next level. The HD650 can reach surprisingly close to that level on a good setup.

If you're spending less than $1,000 on the amp, the chances are that the HD-650 is the better choice (speaking of the 800 vs the 650). I have never heard the 700

If you love the sound of your HD650, chances are you won't like the HD800. Some people on K701/2's gave feedback that the AKGs are more "musical" than the HD800, although I suppose that depends on the amp and DAC/CD/TT too.

I have the HD600 and got to compare with the HD800, both on an X-Can V8 and a Corda Cantate2. The Cantate is a little drier than the V8, but you'd strain to hear it on most recordnings, on the HD600. On either amp the HD800 is noticeably drier than the HD600, BUT as far as I'm concerned, while I liked the HD800 for some recordings, the difference isn't big enough for me to warrant the added expense. So while generally changing headphones/IEMs/speakers would do better to change the sound signature, if you already like what you're using now, then maybe you should look at the other equipment in the system too.

In any case, what's with your HD650's reliability record? I have a five year old HD600 and it's never been broken, not even the stock cable.

Quote:

Originally Posted by Dreamxtreme 

That's what I mean. Would I hear a better sound for the money. I don't plan on pushing the  hd800s to the limit (if there is such a thing) but is it worth the £1000 price tag? 

 Simple stuff - call Amp City UK in London and ask them for their best deal on a Audio-gd NFB-5 - 299 quid at the last check.

 You'd be sorted on the DAC and amp front for either of those headphones in a competent manner.

 http://www.ampcity.co.uk/brands/audio-gd/audio-gd-nfb-5-headphone-amplifier-dac.html

 Oh and you'd really start loving your HD650 too if you don't already. 300mw into 300ohms from the NFB-5 is nice and it does not need that much.

Headphones make the most difference to the overall quality of a setup, unless the rest of it is poor, so generally you want the majority of the budget allocated to them. You would probably hear an improvement (that is, assuming that you like the brighter sound of the HD800), although I am not sure how good the Neco Soundlab Mosfet is, it seems to be some kind of DIY CMOY-type design ? But if necessary, you can sell the HD650, and from the price of that you could buy a better amplifier.

I am in a similar position as the OP, one thing i am considering is trying out recabling the HD650.  Any good suggestions or threads on it?  Perhaps brightening it up a touch.

I don't think that many have heard the HD700, but from the impressions I have read, it seems quite easy to amp. Perhaps even more so than the HD650. The amping requirements seem to be much more strict and usually expensive with the 800. Your price/performance ratio is still best in the HD600/650 area however.

That being said, save your $$$ and forget the aftermarket cable. It is the biggest waste of money in the audio world. The HD650 cable is of phenomenal quality (best in class actually) and your money could be put anywhere else in your audio chain to realize a much more substantial improvement.

Subjective responses of the few who have heard the HD700 have been mixed. Try, if you can, to listen to them (and the HD800) first before you commit to buying them. At two-third the cost of the HD800 the benefit of better sound might make you search for that extra cash.S

I ordered from Amazon the HD650, HD600 and Denon D2000. Kept the HD650. You can order the HD700 and HD800, test them for 30 days and return them both or keep one. I have done this with very expensive Nikon lenses and I never get any hassle from Amazon. This is the least they can do after killing all the brick and mortar stores where you could actually try before buying.

Quote:

Originally Posted by BrunoS72 

I ordered from Amazon the HD650, HD600 and Denon D2000. Kept the HD650. You can order the HD700 and HD800, test them for 30 days and return them both or keep one. I have done this with very expensive Nikon lenses and I never get any hassle from Amazon. This is the least they can do after killing all the brick and mortar stores where you could actually try before buying.

 Thing that keeps me wondering is ~ where do all the slightly used open model headphones/lenses end up?

 Surely at some price point, namely the $1000+ lens kits and headphones - dropping the price drastically is not feasible

 and yet anyone in such a position would pay just that little bit more for new.

 Begs the question ~ where do these 'good as new' goodies with prices close to new end up?