[cfcubed]

So my 2c which should not be valued any more or less than anyone else's 2c around here.  Not to undermine or distract of others' posts here.
 
TomB wondered aloud here why so few members (e.g. w/high DIY post counts / 5-yr+ old join dates) have responded to the "Objective push" going on around here.
Everyone chooses the voices they listen to.  E.g. when a new, loud group enters an ongoing/established group meeting they are usually listened to and then shared discussion ensues.
Assuming some sort of common respect is shown and no one group tries to ignore others' contributions or railroad the discussion.
 
IMO the core issue missed in this Objective/Subjective discussion concerns the claims made.  As long as the supporters of a design do not make false claims about it's quantifiable/measurable aspects I don't see the problem.  And I don't see supports of most popular DIY designs here making specific measurable claims here that could be debated.  
We don't see supporters of, say most any amp with a tube in it, saying its FR & THD is such-n-such.  Only claims in the vein that many like what they hear coming from it. 
 
One can prefer any sort of sound signature or lack thereof.  With some recordings I prefer the voicing/slight mellowing aspects an amp with a tube in it brings.  For other, better source masters, I often prefer all solid-state.
 
E.g. if the value/beauty of a painting was only measured by its accuracy, Impressionism may have never have come about.  All valued paintings would be of the Realism variety.
 
I bet I'll wish I continued to avoid posting.    Few posts in this thread actually address the OP.  Much of this belongs in yet another "If it doesn't measure better it cannot be better" thread.

 

[peppe]

Quote:

I am new to audiophilia, but not electronics. I am currently running an asus Xonar STX --> Ultrasone Pro 750,but the nature of the Xonar adds to the sibilant nature of the highs and seems to further recess the mids on these phones. Not to mention the coldness of the sound.
I would like to build an amp that would be well suited to these phones, bringing out some warmth and taming the highs some.
I have not heard any dedicated hp amps before, so I don't know where to start. I figure the amp would need a low output impedance, because the impedance of the Ultrasones is low, but I don't know if I would be better off with a ss, tube, or hybrid.
Any help would be appreciated. Thanks in advance.

I would say don't overthink it.   Common recommendations for a first amp is a cmoy.  If you don't burn your house down making that, then you have a lot of choices in the $100-300 range.  Most established designs have a lot of X vs Y comparisons available of people comparing them.   Everyones setups are different, so it is hard to distill it, but read enough reviews on an amp and some common threads emerge.
 
When I was doing my search for a first build I ended up on a CKIII.  A lot comparisons done by others of the CKIII vs xxxx usually had CKIII on the warm side.   I wasn't quite sure what sound I would like, but my reading on warmth usually indicated it would be easy to listen to.   So, i figured worst case I have an amp that colors the music in a way that is easy to listen to
 
So far so good, but if you get the DIY bug every project will look tempting. 

 

[wakibaki]

Quote:

Perhaps it would be faster to just tell people what headphones to listen to and how than to tell them how they should be enjoying what they are enjoying their own way.

It's not my intention to act as some kind of killjoy here.
 
Science, electronics and DIY audio are inextricably linked. I couldn't do DIY without understanding electronics, and electronics is based on science.
 
I like radio too, but radio isn't full of people trying to insist that their subjective impressions must be taken into account. We do the science, we build the radios, they work, or they don't work. The degree to which they work is quantifiable and there's no debate about the results. A guy who can design a radio has had to work too hard for his expertise to compromise it by allowing the edges to be blurred by the incorporation of dubious information.
 
I like photography, but photography too isn't full of people insisting that their subjective impressions are taken into account, certainly not as far as the technical aspects are concerned, despite that its no less based on science and engineering than audio. Some people like Nikon lenses, some like Leica, but the absolute arbiter of lens quality is the modulation transfer function. Nobody tries to suggest that Leica lenses are superior to Nikon lenses because of qualities visible to the eye but not documented in the modulation transfer function. 
 
When I discuss the engineering of audio, there's no room for debate. There's what's verifiable, and what's not verifiable.
 
I resist any attempt to turn the subject into morass of grey areas, because it's impossible to do useful work unless you can determine whether improvement has been made. Genuine advances in science are only achieved by those who scrupulously exclude their subjective impressions in favour of instrumented test or human impressions which have been systematically processed to ensure objectivity. Nobody denies that people's hearing is different, but you can't use that fact to justify proceeding on the basis of subjective impressions, because you make no progress.
 
There is a 3rd. area, a true gray area, which is that which is yet to be verified, but this is for discussion by those who appreciate the state of the art. Before anyone can legitimately enter such a discussion, they have to demonstrate both that they know the state of the art and that they know what constitutes evidence in this context. Contrary to what cfcubed seems to think, scientific exploration does NOT operate on a democratic basis. You don't get to vote on the value of Newton's understanding of gravity. You either use it where it is applicable (in non-Einsteinian scenarios), or you are WRONG. You don't get the right answer when you try to predict the motion of the planets. Many people disliked the ideas of Darwin, but he was right and their opinions were valueless in terms of understanding the natural world.
 
Much of audio engineering has al;ready reached the point where the human ear is incapable of distinguishing improvement. If this were not the case, then there would be no question of grey areas, improvements would be obvious. It's because, and only because, it's become possible to throw together a few components and produce a device that performs well enough to be indistinguishable from another similar but different device that debate on the subject has opened up, but that debate is no more than the churn of empty opinion generated by ignorance of the nature of evidence and insufficient self-awareness on the part of those who lean on the expertise of others embedded in the devices they use. The conclusion to be drawn is not that some amplifiers sound better than others, but that many sound identical or near identical, and the subjective impressions of differences are evidence of the fallibility of human judgement.
 
 
To argue otherwise is to subscribe to the logical fallacy that we call 'putting the cart before the horse'.
 
Spectacle lenses are finished only to the lowest quality optical standard, because once gross errors are compensated the wonderfully adaptive human eye and brain are capable of 'tuning out' lesser problems. In exactly the same fashion the ear and brain require only moderate fidelity for the enjoyment of music. Do you imagine the buyers of 78 records went around moaning 'oh, I can't listen to these'?
 
w
 
@ExecuteMethod.
 
Whatever you do, don't spend a lot of money (more than $150) on any amplifier which doesn't both claim to be of reference standard and back up the claim with measurements done on industrial standard testgear.

 

[grawk]

electronics is based on science exactly the same way cooking is.  There's science in there somewhere, but being the guy that reads the schematic and connects the dots or even the guy that designs the circuit ain't science.

 

[drtturnip]

It could be the Grados were designed around the industry standard 120 ohm amplifier output impedance.

 

[jdkJake]

Quote:

 
 
E.g. if the value/beauty of a painting was only measured by its accuracy, Impressionism may have never have come about.  All valued paintings would be of the Realism variety.
 

As a man who values objectivity and scientific method as the cornerstone to his career, nothing surpasses the beauty of what cannot be explained nor adequately characterized. Like the fragile flower, it is beautiful to me because it is.
 
Hence, I seek it out while not discounting for a single moment the immense precision and refinement that made it possible.
 

 

[drtturnip]

 

Driving toward low output impedance is not the best scenario for all low impedance headphones.  I can't speak for Ultrasones, but Grados don't like the very low impedance that comes with most solid state outputs, because it promotes the very thing you're trying to combat: high-end harshness.

 
 
 

It could be the Grados were designed around the industry standard 120 ohm amplifier output impedance.

 

 

[Willakan]

120 ohms is only the "industry standard" according to some ancient document that most manufacturers of both headphones and amps completely ignore. If you want a high output impedance, use an impedance adaptor.

 

[nikongod]

beyerdynamic amps still apply the 120ohm standard.