[thechungster]

So I was comparing them on Sennheiser's website and it says both have a 300Ω impedence. Fair enough. But then this bit really confused me.
HD600 says 97 dB(SPL), at 1 mW
but the HD650 says 103 dB (1 Vrms). What does Vrms mean?

 

[GLdgShDjKsHT]

they are basically the same with the same drivers ... both hard to be driven properly

 

[thechungster]

But there frequency range is both different..

 

[necropimp]

i think eroarex is confusing 600vs650 with 580vs600

the 650 drivers are different from the 580/600 drivers

now that doesn't answer your question and i'm afraid i don't know the answer

 

[bergman2]

just as easy to power

 

[catscratch]

The HD650 is harder to power in my experience, but the impedance is the same and the figures don't really show it that way. However, the HD650 will be lacking in transparency, dynamic range, and bass control, which you really don't measure for usually, until it's finally properly powered, which will most likely involve a balanced amp of some sort. The HD600 may be a bit less sensitive and may need more gain, but it will become transparent and controlled on less powerful systems than the HD650. You can probably get away with a simple single-ended amp as long as it's a good one.

Both headphones are also massively revealing when they're given enough power to properly open up, so you will want a good source. They're capable of performance that's much more high-end than the pricetag would suggest. If they were $1500 people would probably respect them properly and only use them in quality systems, but because of the pricetag a lot of people will match the HD650 with a portable amp and an ipod, and then wonder what the fuss is all about.

 

[sgrossklass]

If in doubt, ask the infamous headphone sensitivity table (OpenDocument format). The two specs work out to an effective 1 dB of difference, or basically nothing. A subjective comparison of 650 and 580 bears this out.

Now the sonics, that's an entirely different matter. The 650s ship with a concert hall for free (or at least the frequency response is somewhat like that), while the 600s are closer to neutral monitoring speakers if still with some studio flair. I eventually switched to the 580s for the computer, as the difference between the 650s and my Tascam monitors was just too large.

 

[tintin47]

First off, Vrms is Volts root mean square. It basically means average. Usually sensitivity specs are given in mW, though. Those numbers are easier to work with because they actually deal with the power your amp is putting out at a given time.

 

[Lil' Knight]

In my experience, the HD650s scale better when driven by proper amp, especially balanced.

 

[thechungster]

Ok, so I will be getting the nuforce icon mobile amp (For my IE8s first) In the massive review HPA did, he said that it did alright with the HD600's. But I'm just not sure now if they will be good enough for the HD650s.

 

[riceboy]

Quote:

Originally Posted by Lil' Knight /img/forum/go_quote.gif In my experience, the HD650s scale better when driven by proper amp, especially balanced.

Agreed. This is my experience and I've owned both the HD650s 3 times and HD600 2 times as well so I've had much time with them on different sources, amps and cables.

 

[radiohead7]

I have heard conflicting opinions about using the RSA mustang to power the HD650 but i did hear from ray sameul that the P-51 was designed around the hd600s. Other reviews i have read on here have pointed out that the hd600's will amp better with this portable amp. A few would say they were happy with the 650's despite me hearing that they are harder to drive with the p-51.Everyone said it did help. Is this accurate information?

 

[Lil' Knight]

The P51 drives my HD600/650 to a listenable sound (high enough volume, acceptable SQ) at high gain. As long as you won't use the P51 to drive the Senns permanently, it's fine to try that for the time being.

 

[Trav]

After today I've heard the 650 in every Uber configuration imaginable and IMO the 600 is hands the best and am kicking my own butt for selling them.......

 

[madmax7]

Quote:

Originally Posted by Trav /img/forum/go_quote.gif After today I've heard the 650 in every Uber configuration imaginable and IMO the 600 is hands the best and am kicking my own butt for selling them.......

I agree. The 600 is sounding so very good to me. I actually think they sound better out of the Ipod/RSA Hornet "M" than they do with my Rotel/Woo3 setup. And I have realy nice tubes in the Woo. Two matched Telefunken NOS 6DJ8's and a Western Electric 421A. The Rotel is known to be a little bright though. Love these cans!