[skeptic]

Nothing more than to increase the awareness that specifications matter. 

For instance, the Vali has a THD of <0.4% while my Woo3 has a THD of <= 0.08%.

Does this matter?  Maybe, maybe not.

Will the Woo3 sound better?  Maybe, maybe not.

Hi USG! Good to see you back in the thread!

A couple of comments on the above I think you may find intriguing - first, as a fellow (now former) woo 3 owner, I sincerely doubt the validity their posted specs on their Otl's. The Woo 3 and 2 are both much slower and tubier sounding than the crack, which is faster, more detailed and more dynamic by comparison, especially with the ccs boards in place. Crack is objectively a better more sophisticated circuit. The cost differential is labor and fancy case work.

That said, in his diy comparison thread, wyldrage measured (with a humble emu 0404 setup) the crack as having distortion higher than what schiit publishes for the vali - around .8% if memory serves. But it really does sound better, and cleaner, than the woo 3 and much better, to my ears, than my o2 with high impedance Senns. My guess is that woo's measurements are off by a lot. Jack Woo personally commented that his transformer coupled amps sound more solid state than the OTLs. Woo's published distortion measurements (way worse for the transformer coupled than for the OTLs) can't be reconciled with that comment.

Finally, I'm actually a fan of measurement first amps, as well as good tube amps. I am presently working on both a wire se se (half finished) and the really cool agdr booster board for my o2 (debugging), which brings a battery powered o2 within spitting distance of the wire. Even stock, I love my o2 with my alpha dogs, my westone 4s and even my dt880's, but for whatever reason, it just doesn't work for me at all with my hd650's. The engaging magic just isn't there to my ears. More power to those who find complete happiness with what is irrefutably an incredible budget performer, but notwithstanding their measurements, nonfeedback SET designs seem to just play really nicely with hd650's as I and many others hear them. Maybe the distortion is in a sense simply compensating for the room effects we don't get with headphones?

Keeping it real though, I was advocating the crack in this thread back in 2011 and was largely ignored. Now it's all the rage and I'm still a big fan of my crack and listen to it with my hd650's just about every day - but even hotrodded, it isn't the equal of a zana and certainly not the equal of bottlehead's mainline or others of that caliber. A great match for hd650's, no doubt. Better than even the woo 2 at twice the cost, I would say yes. But it is hyperbole to suggest that it is where the buck stops for this or any other headphone in my opinion.

 

[atraf]

The Vali/Modi combo sounds really good with 650's. Asgard 2 should be more flexible with IEMs though, and has similar sound signature as Vali.

How is the bass/midbass with the vally? is it really giving you that oomph that I am looking for, that tumble on the ears? 
Sound wise what does it mean that the vally is hybrid ? 
 
Basicly i am asking does it worth paying double and get the valhalla/bifrost combo?

 

[Zojokkeli]

I don't have experienced enough ears so I can't say anything specific in audio-language, but I find the bass surprisingly strong. Definitely enough for electronic music, IMO. I'm coming from HD 598's and this is the best I've ever heard, so maybe someone with more experience can give you more detailed information.

 

[skeptic]

In reference to the discussion of headphone amp measurements above, I stumbled on an interesting new article today written by Benchmark's engineers and published by Enjoythemusic.  It provides a nice concise explanation of at least one common problem with amp measurements due to manufacturer's frequent use of resistive loads rather than actual headphones when testing.  Evidently, this skews the results in a significant way.
 
http://www.enjoythemusic.com/magazine/manufacture/0414/headphone_amplifiers_specifications.htm

 

[upstateguy]

Hi USG! Good to see you back in the thread!

A couple of comments on the above I think you may find intriguing - first, as a fellow (now former) woo 3 owner, I sincerely doubt the validity their posted specs on their Otl's. The Woo 3 and 2 are both much slower and tubier sounding than the crack, which is faster, more detailed and more dynamic by comparison, especially with the ccs boards in place. Crack is objectively a better more sophisticated circuit. The cost differential is labor and fancy case work.

That said, in his diy comparison thread, wyldrage measured (with a humble emu 0404 setup) the crack as having distortion higher than what schiit publishes for the vali - around .8% if memory serves. But it really does sound better, and cleaner, than the woo 3 and much better, to my ears, than my o2 with high impedance Senns. My guess is that woo's measurements are off by a lot. Jack Woo personally commented that his transformer coupled amps sound more solid state than the OTLs. Woo's published distortion measurements (way worse for the transformer coupled than for the OTLs) can't be reconciled with that comment.

Finally, I'm actually a fan of measurement first amps, as well as good tube amps. I am presently working on both a wire se se (half finished) and the really cool agdr booster board for my o2 (debugging), which brings a battery powered o2 within spitting distance of the wire. Even stock, I love my o2 with my alpha dogs, my westone 4s and even my dt880's, but for whatever reason, it just doesn't work for me at all with my hd650's. The engaging magic just isn't there to my ears. More power to those who find complete happiness with what is irrefutably an incredible budget performer, but notwithstanding their measurements, nonfeedback SET designs seem to just play really nicely with hd650's as I and many others hear them. Maybe the distortion is in a sense simply compensating for the room effects we don't get with headphones?

Keeping it real though, I was advocating the crack in this thread back in 2011 and was largely ignored. Now it's all the rage and I'm still a big fan of my crack and listen to it with my hd650's just about every day - but even hotrodded, it isn't the equal of a zana and certainly not the equal of bottlehead's mainline or others of that caliber. A great match for hd650's, no doubt. Better than even the woo 2 at twice the cost, I would say yes. But it is hyperbole to suggest that it is where the buck stops for this or any other headphone in my opinion.

 
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.

 

[connieflyer]

A good amp should only change the amount of the signal not the content.  Any coloration changes the sound of the output, good or bad.  How close the input to the output other than the amount of signal would show a good amp as opposed to an amp that is making music.

 

[JamieMcC]

A good amp should recreate a sonic signature that you enjoy listening to, everybody has different tastes.
 

 

 

[olegausany]

A good amp should recreate a sonic signature that you enjoy listening to, everybody has different tastes.
 

 

+1

 

[upstateguy]

  In reference to the discussion of headphone amp measurements above, I stumbled on an interesting new article today written by Benchmark's engineers and published by Enjoythemusic.  It provides a nice concise explanation of at least one common problem with amp measurements due to manufacturer's frequent use of resistive loads rather than actual headphones when testing.  Evidently, this skews the results in a significant way.
 
http://www.enjoythemusic.com/magazine/manufacture/0414/headphone_amplifiers_specifications.htm

 
I've read this before. 
 
It could have been an interesting article if we knew the names of the dac/amps used in the comparison.
 
Or even better if it compared the Benchmark stand alone $450 H1 headphone amp to some other well known amps.  
 
According to Benchmark "Inside the H1 is Benchmark's signature headphone amplifier module, the HPA-2™."
 
Without knowing what was compared to what, we have to assume it's nothing more than Benchmark's advertising razzmatazz.
 
But while I was looking for info on how the Benchmark HPA-2 amp drives 650s, I found this post from Elias Gwinn, a Benchmark engineer,: (http://www.amb.org/forum/benchmark-engineer-on-balanced-v-unbalanced-headphone-amps-t326.html)
 
ALL headphones have non-linear mechanical impedances (that is, the mass and shape of a speaker will resonate more at certain frequencies and much less at other frequencies). This means the physical build of the headphones (as well as other physical impedances, like your head and ears!) will try to override the electrical system (amplifier and speaker coil).
 
To create low-distortion headphone response, one must consider 'damping factor'. A high damping factor will control the response of the speaker, thus preventing the physical impedances from dictating frequency response. Damping factor is the ratio of speaker (load) impedance to amplifier (source) impedance. In other words, the best damping factor will result from a low source impedance. Again, the source impedance from the HPA2 is less then 0.01 ohms...as low as gets!!
 
Balanced headphone amps will double the source impedance of an unbalanced headphone amp. No matter how low the impedance of a balanced headphone amp, it could be half that much if it was unbalanced. This is one reason balanced headphone amps are not a good idea. (It should also be noted that the balanced output of the DAC1 / USB / PRE is 60 ohms or greater, depending on the attenuator settings).
 
Not only will the source impedance double with balanced headphone amplifiers, but the total distortion and noise of the amplifier will double as well!! Every output device (opamp, transistor, tube) creates some distortion and some noise. If there are two opamps or transistors or tubes driving each headphone speaker, twice as much distortion and noise will be added!!
The result of balanced headphones is less damping factor, more distortion, and more noise. Also, balanced headphones configurations offer no real benefits, to boot.
 
Feel free to use the XLR outputs of the DAC1 / USB / PRE for balanced headphone outputs (as mentioned above, the DAC1 USB and DAC1 PRE will do better then the DAC1 at this task, because of the 4562's). It won't damage anything to operate in this configuration. But, for the reasons above, I don't recommend it.
 
Thanks,

Elias

 

[upstateguy]

  A good amp should recreate a sonic signature that you enjoy listening to, everybody has different tastes.
 

 

 
You can do the same thing with DSPs and an equalizer. 

 

[olegausany]

 A good amp should recreate a sonic signature that you enjoy listening to, everybody has different tastes.
 

 

 
You can do the same thing with DSPs and an equalizer. 

Unfortunately it's not so easy. I spent a lot hours playing with 3 different equalizers but was unable to get sound i was when driving D7000 with WA7 and it took me just a few minutes to get what i want while driving HD650

 

[Solrighal]

Hi folks. I've got the itch again and want to buy another pair of headphones. My current open cans of choice are my AKG Q701's. I also have a pair of V-Moda M-100's & Shure SRH840's. I want something different, something with a bit of warmth to the sound. I still want detail. I'll be driving them mainly with my ODAC / O2 (1x/3x gains) & occasionally with my Fiio E18. Will these amps drive the HD650?

I'm torn between the HD600 & HD650. Can someone explain what either would give me that's better than my Q701's? Sell these headphones to me.

 

[joebobbilly]

Hi folks. I've got the itch again and want to buy another pair of headphones. My current open cans of choice are my AKG Q701's. I also have a pair of V-Moda M-100's & Shure SRH840's. I want something different, something with a bit of warmth to the sound. I still want detail. I'll be driving them mainly with my ODAC / O2 (1x/3x gains) & occasionally with my Fiio E18. Will these amps drive the HD650?

I'm torn between the HD600 & HD650. Can someone explain what either would give me that's better than my Q701's? Sell these headphones to me.

You're in the HD650 thread... I think you already know what our answers here will be

 
Assumptions aside, the difference between the two is not extreme, but I'd argue the HD650 would be a better "contrasting complement" to your Q701. Unless you really cannot stand a warmer mid bass that is slightly more "coloured and euphonic" I'd say HD650 is the better can.

 

[Solrighal]

I'm looking for something to complement the Q's. I've always wanted the HD650's but they've held their price well. Do you think the O2 will be able to drive them though?

 

[nivikus]

Hi everyone, just jumped on the HD650 bandwagon and I'm looking to of course pair them with an amp. But, I'm having a tough time deciding what I want to go with. My main focus is on speed, mid-range and soundstage. I listen to mostly electronic music but definitely have some post rock and classical in there. I'm more interested in lush and entertaining sound. Not analytical or fatiguing.  My budget is around $300.
 
A lot of people in this thread seem to really recommend the Bottlehead Crack and that is coincidentally around my budget. However, the Speedball upgrade also comes highly recommended and that definitely puts me over budget. It would drive me crazy knowing I'm missing out.
 
So, forgetting the BH Crack for a moment, what's some other great amps that pair really well with the 650? I've been seriously considering the Valhalla, the Maverick TubeMagic D1, and the iCAN iFi. A lot the reviews right here at head-fi say the Xbass and 3D mode on the iCAN aren't actually gimmicks, and I think I would enjoy that for gaming. Thoughts?