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Dear Diary / Please Let Me Rant Here Because I Have Nowhere Else
I got into college today. I was ecstatic and so ridiculously happy. I still AM ecstatic!
However my parents are disappointed in me. I did not get into Ivy Leagues or anything with "prestige" that they consider good.
They are both foreign parents and they think the college I got into is a bad school.
I know it isn't but they are giving me **** for it and now I don't know what to do. I am so happy yet my parents are telling me that I am dumb and that I should take a gap year and reapply next year.
I really just wish that they would smile and give me a hug like normal parents would, not to mention on the day I got accepted to a college that I was really hoping to get into. Instead all they can focus on is the rejections. It is the worst feeling ever when your parents come home on the big day and ask you where you got in, and when you say where they frown and ask "is that it?"
I really am glad that I at least have some friends who support me. And I support them too.
I hate this family. But I love them. Do you see where the root of my problem lies?
Congratulations. I hope it works out well for you. A college's ranking isn't too terribly important. America's educational system is so messed up the a bachelor's degree is basically just a fancy high school diploma. Unless you have a specific career plan it's more important that you just get one rather than worry about what it's in or how well the school is regarded.
Also, if you even
think you're having any issues with depression take advantage of the student health plan and just see a psychiatrist as a precaution. Many colleges but plenty of money into their mental health clinics just to avoid parents suing over their kids committing suicide. I'm not saying that your going to do that or anything but just explaining why I think you'll be able to see if you need any kind of help and get whatever help you might need.
I had a similar experience that turned out rather poorly and I don't want to see anyone repeat it if I can help it. I was accepted into the electrical engineering program at UIUC which was ranked #3 in the country at the time. I had some issues, didn't get help fast enough, got booted out of the EE program, and am still trying to get my life on track.
As for your parents, this may end up sounding a little harsh but I don't mean it that way. It more about understanding where they're coming from. Pretty much all parents suck at raising their kids. It's not because they're mean or stupid, it's just because raising kids is really,
really hard to do. There are plenty of places to get bad advice and few to good advice. They are probably trying their best to help you but they're just not working from the best information.
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On that front, a few days ago I emailed Woo about the output impedance for my WA6, expecting it to be rather high and thus negatively affecting my UERM performance, and I'm still waiting for a reply...
I'm not up for the calculations right now but it looks pretty high to me. You can figure it out yourself from the power numbers
here if you're interested. Look up the formulas for how the poer is divied between the amplifier's impedance and the load (i.e. the headphones) impedance.
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This is what I mean though. This is an important specification, how could it have been printed wrong in the first place? Normally I would give them the benefit of the doubt, but there is a particular history here.
I'm a little hesitant to talk more about this though.
I remain skeptical as well...
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Maybe I've just been blind to it, but output impedance seemingly has come out of nowhere to be this very important spec. I'd never heard it mentioned until this last year and I've been around HF for almost 10 years now.
Even two years ago when I joined no one seemed to care about any specifications at all. I knew about most of this stuff but I just kind of assumed that it wasn't an issue because no one talked about it because it was taken care of in solid state designs like after the damping factor craze with power amps went away. Later I found out just how messy and unstandardized this whole market is.
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I know that it seems like output impedance has been a bit of a buzzword spec at the moment, and I was a little worried at first. There is enough measurable data and information on the internet though, and from
Stereophile no less, that makes the point that output impedance is a rather important figure that affects performance.
I don't think it has been a problem for headphones with their relatively high impedances (far higher than the 4/6/8 ohm impedances of speakers) until now, when there are a number of headphones on the market with impedances low enough that interaction with the amplifier's impedance is an issue.
I'm not saying that it is the be all and end all spec, and I would think things like THD, slew rate, etc etc are equally important. But this seems like an important question when discussing portable devices and desktop amplifiers that might be seeing some low impedance loads.
Besides just being new to many people its probably more of a buzzword because its easier to understand, easier to hear, and is more variable among different products. With real music nobody is going to tell the difference between .01% and .005% THD and at the low voltages that headphones use its dead easy for the cheapest design to have plenty of slew rate.
Output impedance is also more easily captured in one number. Assuming that an amp has enough distortion to actually be audible you really need a graph to show the harmonic composition of the distortion to have any clue what it will actually sound like. Something like .01% is so low that pretty much no matter where the distortion is you won't be able to hear it. OTOH a tube amp which is working hard could easily end up with 3% and not even sound that bad while any normal solid state design with 3% THD would almost certainly sound horrendous due to the different harmonic content.
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There's probably nothing wrong with the Classic if you're using an amp. Portable amps shouldn't care about the output impedance of what's upstream.
Output impedance was a major obsession in the 1960s, only in the context of an amplifier's
damping factor, the ratio between the input impedance of the speaker and output impedance of the amp. By the 70s it was rare to see damping factor touted on spec sheets, since it was relatively easy for amplifier makers to produce solid state amps with near-zero output impedance and DF figures in the tens of thousands.
Remember that 2 ohm loads in the speaker world are rare, but by no means bizarre, and 6 ohms is common. A high damping factor is arguably even more critical for speaker amps and harder to achieve, yet it's ceased to be a meaningful figure.
This is why I don't really marvel at low-Z headphone amps, where 32 ohm is considered a nominal load. I am mostly curious why there are so few of them.
If I got an iDevice it would be a Classic and I'd use an amp as a buffer to lower the output impedance. IMO all DAPs on the market have a fatal flaw so you have to pick your poison. Output impedance can at least be fixed with an external device but a lot of other issues aren't so easy.
I think there are a few reasons why output impedance varies so much on headphone amps. One is that most head amps are op amp based op amps don't actually drive low impedance loads all that well. Extra impedance is often added to keep them stable or well behaved into lower impedance headphones. Power transistors and chip amps used for speaker amps don't really have those issues but aren't well suited for head amps, especially portable ones. That leaves a gap in the middle with only a few op amps like the 4556 in the O2 and think like the TI and National buffer chips which work well for headphones without sucking down tons of power or taking up lots of space.
The second is that different output impedances will make things sound different and lots of people will equate different with better.
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Specification
measurement standardization would be nice, but I'm in the camp that suspects that although we can measure many things that we know affect audio quality, we do not yet necessarily know how everything is relevant to audio fidelity, and how to gauge it all meaningfully. The
following quote comes to mind: "If it measures good and sounds bad, it is bad; if it measures bad and sounds good, you have measured the wrong thing."
I'd say that either way you measured the wrong thing. Psychoacoustics is really what determines whether something sound good or not.
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The MDR-MA900s look like an improved version of F1s. They have 70 mm drivers! Similar impedance to F1s and also have that "acoustic bass lens". MA900s should deliver more bass / impact than F1s due to less ventilation/openness and bigger driver. I really want to know how MA900s sound and feel (comfort wise) in reality.
With 70mm drivers I wonder how or if they handles cone break up. Sennheiser tried the best they could to deal with the issue in a large full range driver and ended up having to punch a hole in the middle and make a "ring radiator" to get the results they wanted.
On something like the XB1000 where nobody was going to care about the treble anyway it probably wasn't much of an issue to use such a big driver but if this really is following in the footsteps of the F1 and going for sound stage they do have to care about it.
My guess is that they just decided to forget about the bass and limit excursion to keep the treble nice and clean...
I actually just bought a set of used F1s for their comfort / ventilation features.
