[Solrighal]

I recommend the Forza Audioworks cables. Reasonably prized, fantastic build quality and no fear of customs fees inside EU.

I've actually been looking at their site and its impressive. I see all their cables use copper rather than the fashionable silver. I've yet to read any accounts of their cables audio qualities though so I'm not sure. Either way I need to wait and see how I like the stock cables first.

Does anyone know how long the HD650's take to burn-in?

 

[weitn]

  Anyone using the HD650 as their portable headphone?
 
I'm looking at the HD650 for use during walks and chores around the house.  I'll be mating it with the AK120 and the Pure II amp (at least that's the plan).
 
Also-I just received my HD650's last week and plugged them into my 5th gen IPod and was unimpressed.  It was dreadful sounding IMHO.  Is this because the HD650's need allot of power to perform?
 
Am I correct in assuming that I will notice a  HUGE improvement when driven by a separate amp?  I sure hope so because I'm about to return them.

 
Have you break-in the HD650 for about more than 200 hours? Other option is upgrading the cable.

 

[JacobLee89]

I've actually been looking at their site and its impressive. I see all their cables use copper rather than the fashionable silver. I've yet to read any accounts of their cables audio qualities though so I'm not sure. Either way I need to wait and see how I like the stock cables first.

Does anyone know how long the HD650's take to burn-in?

 
Some say none, some say between 100-200hrs. A recent post said that their "repaired" HD650's sound different than when they sent it in, so I think that there is (a burn-in time) but the transition is difficult to notice.

 

[Solrighal]

Some say none, some say between 100-200hrs. A recent post said that their "repaired" HD650's sound different than when they sent it in, so I think that there is (a burn-in time) but the transition is difficult to notice.

Thanks. I remember I once owned a pair of HD595's and they seemed to benefit from burn-in. I was ever particularly happy with the though. Very boring sound if I remember right. I noticed benefits when burning in my V-Moda M-100's but my AKG Q701's didn't change one bit.

 

[Zojokkeli]

  Am I correct in assuming that I will notice a  HUGE improvement when driven by a separate amp?  I sure hope so because I'm about to return them.

You should get a proper amp and DAC to get the most out of your cans. I tried listening my 650's through Nuforce Icon uDAC 2 and they sounded very bland compared to Schiit Modi/Vali; I imagine listening straight from ipod will sound even worse. If you're looking cans for mostly portable use, I suggest trying Sennheiser Momentums. They sound amazing from pretty much anything and require zero amplification.

 

[Solrighal]

You should get a proper amp and DAC to get the most out of your cans. I tried listening my 650's through Nuforce Icon uDAC 2 and they sounded very bland compared to Schiit Modi/Vali; I imagine listening straight from ipod will sound even worse. If you're looking cans for mostly portable use, I suggest trying Sennheiser Momentums. They sound amazing from pretty much anything and require zero amplification.

I'd have to agree. Using the HD650 as a portable will involve so many compromises it'll drive you mad. The Momentum is an option as is the V-Moda M-100 & the AKG K550. All of those will do the job better.

 

[Androb]

I'd have to agree. Using the HD650 as a portable will involve so many compromises it'll drive you mad. The Momentum is an option as is the V-Moda M-100 & the AKG K550. All of those will do the job better.

Well 650 + fiio e12 is atleast working. Far from as good as it can be but I can't complain that much about the sound

 

[joebobbilly]

  Anyone using the HD650 as their portable headphone?  
 
I'm looking at the HD650 for use during walks and chores around the house.  I'll be mating it with the AK120 and the Pure II amp (at least that's the plan).  
 
Also-I just received my HD650's last week and plugged them into my 5th gen IPod and was unimpressed.  It was dreadful sounding IMHO.  Is this because the HD650's need allot of power to perform?  
 
Am I correct in assuming that I will notice a  HUGE improvement when driven by a separate amp?  I sure hope so because I'm about to return them.

IEMs generally are the smarter choice for portable IMHO. But what exactly do you find lacking from the sound? That would help clear up what advice we can offer to help you.

 

[rEEcEj]

I used them with a a very high end sound card before which drove them to the limit, but I had to replace the sound card with a Scarlett 2i2, can anyone tell me if the Scarlett 2i2 is good enough to power the HD650s and which headphone amp I should add to the mix? Also whether I should replace the cable.

 

[skeptic]

Hi rEEcEj - per your question, replacing headphone cables is largely cosmetic (or because the length is unwieldy in your particular setup) and should be last on your list of potential sonic upgrades.  Unless your original cable happens to have been damaged or defective, there will be no measurable changes brought about by cable upgrades (a fact which is acknowledged by many reputable cable makers), although many listeners still seem to perceive subtle improvements.  There is an open question as to whether or not this is psycho-acoustic or whether there are, in fact, audible criteria that simply are not being measured by conventional means.  One thing that is clear is that common claims that copper cables are "warm" and silver cables are "bright" are demonstrably false.  Those changes, if they occurred, would show up in traditional FR measurements, and they simply don't.   (Impedance mismatches in cable connectors, however, can have a demonstrable impact on signal integrity.  Even in digital signals, bits can literally "bounce" causing time domain issues, although I understand this is a more serious issue in high frequency applications.) 
 
In short - spend your money on a good amp or dac (in that order, in my opinion).    

 

[atraf]

You guys really surprised me, saying that the O2 is in the same league as Valhalla so why the hack people spend 350$ when they can spend so much less? 
I really thought about investing 400$ in a dac/amp combo but now your telling me its a waste of money cause I can get the same sound with something that cost a lot less. 
my problem is that there is no place for me to listen to any amp/dac before I purchase them, so I can only trust your reviews :\

 

[skeptic]

Hi Skeptic, how are you these days?

 
There's much to discuss, but since this is a 650 thread let's investigate why some amps sound better with your 650s and not your 880s. Is this just with the O2 or does it apply to other amps as well? 
 
I think I understand what you're saying about the crack.  Maybe it boils down to having more resolution than the Woo3, which might translate into descriptors like, faster, more detailed and more dynamic.
 
The problem I have is understanding what about a zana would make it sound better than a wire with gain amp like the GS-1 I have.  Is it the coloration and harmonic distortion added by the tubes?
 
Sounding different I can understand, relative coloration and resolution, but I seem to be under the impression that the only thing a good amplifier does is amplify the signal without changing it.
 
In any event, we are on the same page.

 
It is a great question you pose, and I wish I had a great answer.  I actually really like how my 250ohm dt880's sound with my crack, albeit slightly less than I like the pairing with my hd650's.  What I find so puzzling is that I also really like the dt880's with my O2, but I don't like my hd650's with my O2 much at all.  The O2 clearly and understandably excels with high sensitivity orthos like my AD's (and at unity gain, with my Westone 4's), but the dt880's and hd650's are both high impedance phones of similar sensitivities that one would tend to assume would behave similarly.  Aside from the extra 50 ohms, which is going to mean the hd650's are getting a little less power than the dt880's, my best guess is that it comes down to sound stage and spatial cues.  
 
The dt880's are a little more spacious but less coherent sounding to start with, and I think the O2 brings that under control and focuses the sound.  The hd650's, by contrast, are really coherent and focused sounding straight out of the box, and a little less spacious in terms of sound stage.  The crack, and other good tube amps I've heard, make the hd650's sound a little more expansive and involving in a very good way (at least to my ears) - presumably something to do with the impact of even order tube distortion.  When I plug them into the O2, their already very coherent focused sound is left as is, and I don't perceive them as sounding much better, if at all, than out of the jack on my Marantz receiver.  As 300 ohm headphones, they also don't really benefit from the superb noise floor on the O2 to the same extent as lower impedance headphones.
 
I still haven't heard the GS-1, and I would love to be able to AB it with something like my mainline or a zana.  My understanding is that KG's designs don't really fall within the "wire with gain" philosophy and actually add a hint of warmth to the sound of my headphones.  Unlike the O2, my impression was that the GS1 and other dynalo derivatives don't rely on the same degree of global feedback as "measurement first" amps - which I have also read can cause interesting disproportionate impacts on very high order distortion.  Although extremely low in magnitude, I wonder if the global feedback issue isn't tied into the reports of subtle "glare" that some listeners seem to perceive with the O2.  Obviously, this is well above the threshold of fundamental frequencies, but high order harmonics are the controlling factor in our perception of timbre... 
 
Also - thanks for your comments regarding benchmark and the significant downsides of going balanced.  I had read Elias Gwinn's debate with AMB on the balanced issue a while back and found Gwinn's position very persuasive.  (http://www.amb.org/forum/benchmark-engineer-on-balanced-v-unbalanced-headphone-amps-t326.html).  (I think you also raised a very interesting point regarding benchmark's lack of specificity as to the amp modules included in their products.  In a sense, you have to wonder if they are looking to avoid the sort of scrutiny that they are directing towards competitor's products.)
 
That said, with the exception of Pass Lab's recently expired SuSy patent, it seems like there is a lot of truth backing up the argument that balanced amps have more cons than pros. To recap: unless you need the extra power to drive an inefficient transducer, push-pull or, alternatively, bridged amps generally add noise and distortion (excluding, in push-pulls, common mode distortion - which is really only relevant to long cable runs).  They also raise output impedance/reducing damping (theoretically bad but which may or may not be to the tastes of the user at issue).  Most notably, they cost about twice as much to build.  On the flip side, you get double the voltage and double the slew rate, but the latter is believed by most to be inaudible in the context of any competent amplifier.   
 
I don't have the technical background necessary to fully appreciate the why of it, but if you look at Pass Lab's technical summary article, you will note that Pass essentially agrees with the Benchmark guys in so far as suggesting that the 3 traditional balanced approaches either perform worse than, or at best, equal to, ordinary 2 channel single ended designs.  https://passlabs.com/articles/super-symmetric-amplification  SuSy amps, as discussed in the link, are evidently a different matter.  

 

[Androb]

  You guys really surprised me, saying that the O2 is in the same league as Valhalla so why the hack people spend 350$ when they can spend so much less? 
I really thought about investing 400$ in a dac/amp combo but now your telling me its a waste of money cause I can get the same sound with something that cost a lot less. 
my problem is that there is no place for me to listen to any amp/dac before I purchase them, so I can only trust your reviews :\

Well I got a few different Amps, and it sure sounds alot better on some. So I dunno about that.

 

[mbusby]

I run it out of my PC via spdif optical to a v-dac and then into a project horizon (using a 6dj8 holland orange globe).
 
Dat bass....

 

[upstateguy]

   
It is a great question you pose, and I wish I had a great answer.  I actually really like how my 250ohm dt880's sound with my crack, albeit slightly less than I like the pairing with my hd650's.  What I find so puzzling is that I also really like the dt880's with my O2, but I don't like my hd650's with my O2 much at all.  The O2 clearly and understandably excels with high sensitivity orthos like my AD's (and at unity gain, with my Westone 4's), but the dt880's and hd650's are both high impedance phones of similar sensitivities that one would tend to assume would behave similarly.  Aside from the extra 50 ohms, which is going to mean the hd650's are getting a little less power than the dt880's, my best guess is that it comes down to sound stage and spatial cues.  
 
The dt880's are a little more spacious but less coherent sounding to start with, and I think the O2 brings that under control and focuses the sound.  The hd650's, by contrast, are really coherent and focused sounding straight out of the box, and a little less spacious in terms of sound stage.  The crack, and other good tube amps I've heard, make the hd650's sound a little more expansive and involving in a very good way (at least to my ears) - presumably something to do with the impact of even order tube distortion.  When I plug them into the O2, their already very coherent focused sound is left as is, and I don't perceive them as sounding much better, if at all, than out of the jack on my Marantz receiver.  As 300 ohm headphones, they also don't really benefit from the superb noise floor on the O2 to the same extent as lower impedance headphones.
 
I still haven't heard the GS-1, and I would love to be able to AB it with something like my mainline or a zana.  My understanding is that KG's designs don't really fall within the "wire with gain" philosophy and actually add a hint of warmth to the sound of my headphones.  Unlike the O2, my impression was that the GS1 and other dynalo derivatives don't rely on the same degree of global feedback as "measurement first" amps - which I have also read can cause interesting disproportionate impacts on very high order distortion.  Although extremely low in magnitude, I wonder if the global feedback issue isn't tied into the reports of subtle "glare" that some listeners seem to perceive with the O2.  Obviously, this is well above the threshold of fundamental frequencies, but high order harmonics are the controlling factor in our perception of timbre... 
 
Also - thanks for your comments regarding benchmark and the significant downsides of going balanced.  I had read Elias Gwinn's debate with AMB on the balanced issue a while back and found Gwinn's position very persuasive.  (http://www.amb.org/forum/benchmark-engineer-on-balanced-v-unbalanced-headphone-amps-t326.html).  (I think you also raised a very interesting point regarding benchmark's lack of specificity as to the amp modules included in their products.  In a sense, you have to wonder if they are looking to avoid the sort of scrutiny that they are directing towards competitor's products.)
 
That said, with the exception of Pass Lab's recently expired SuSy patent, it seems like there is a lot of truth backing up the argument that balanced amps have more cons than pros. To recap: unless you need the extra power to drive an inefficient transducer, push-pull or, alternatively, bridged amps generally add noise and distortion (excluding, in push-pulls, common mode distortion - which is really only relevant to long cable runs).  They also raise output impedance/reducing damping (theoretically bad but which may or may not be to the tastes of the user at issue).  Most notably, they cost about twice as much to build.  On the flip side, you get double the voltage and double the slew rate, but the latter is believed by most to be inaudible in the context of any competent amplifier.   
 
I don't have the technical background necessary to fully appreciate the why of it, but if you look at Pass Lab's technical summary article, you will note that Pass essentially agrees with the Benchmark guys in so far as suggesting that the 3 traditional balanced approaches either perform worse than, or at best, equal to, ordinary 2 channel single ended designs.  https://passlabs.com/articles/super-symmetric-amplification  SuSy amps, as discussed in the link, are evidently a different matter.  

 
I have read that some people think the KG designs slightly warm, but I never heard the GS-1 that way.  The GS-1 has much more information in the upper registers and has a significantly higher resolution than either my M^3 with 637/627s or my Woo3 with a Cetron power tube .  I would classify both  the M^3 and Woo3 as having warmish presentations relative to the GS-1 but not the holographic effect the GS-1 has.  Curiously, the M^3 (637/627) and the Woo3 (Cetron) have extremely similar sound signatures and I have found my 650s sound almost the same from either one with maybe a hint more bass from the Woo's second order harmonic.... maybe.
 
Regarding the O2, the GS-1 can play louder than the O2 but I don't think I'd want to bet on my ability to distinguish between the O2 and the GS-1 at moderate listening levels with my T-1s (dac used was a North Star 192MKII with either a Blue Circle Thingee or a HiFace transport, ... the HiFace having more resolution and a hotter treble than the BCT and the Thingee having less resolution but a better tone ).  Unfortunately, once I discovered no apparent JND between the O2 and GS-1 with the T-1s, I never bothered to compare extensively or further with the 650s, '04/880s, or the 701s I almost never use. 
 
These days I use the O2 with a laptop, a Pico dac and 880s when I'm away.  When I am at home, I use the same laptop but with the HiFace/North Star/GS-1 and either the 650s or T-1s depending on mood and program material.
 
What I did notice recently was that when both the 600ohm T-1s and the 300ohm 650s were plugged into the GS-1 at the same time, the T-1 played louder than the 650s.
 
Now I'm thinking about another direction.... Harbeth P3ESR or KEF LS50 and some kind of compact dac-amp like a Peachtree Nova....  maybe