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Good articles to read if you have a lot of time:
http://en.wikipedia.org/wiki/Gramophone_record
http://en.wikipedia.org/wiki/Loudness_war
http://en.wikipedia.org/wiki/Amplifier
http://en.wikipedia.org/wiki/Tube_amp
http://en.wikipedia.org/wiki/Op_amps
http://en.wikipedia.org/wiki/Lossless_audio
This is just a quick post to clarify some headphone myths
1) How do headphones work?
Standard dynamic headphones essentially work by moving current through a thin wire. This wire is placed next to a magnet, so that the resulting magnetic field moves the wire back and forth. If you attach a thin material to the wire, you can move air and thus produce sound waves which match the voltage waveform that enters the headphone.
There are other kinds of headphones, but those are uncommon and pretty much only exist in the audiophile market.
2) Why do headphones have different resistance ratings? (i.e. 8ohm vs 600ohm)
Certain drivers are much larger than others. In other words, they move MORE air than other drivers. This means that you need more power to effectively move the coils and fight the force of friction (air resistance, etc.). Certain drivers are less power efficient. Certain drivers even ARTIFICIALLY add resistors into the circuit purely to increase input resistance. Having high resistance is often beneficial, because you want the output resistance of your amplifier stage to be lower than the input resistance of your headphones. However, there are drawbacks to having too much input resistance. The real explanation is quite long, but a good, simplified way to think about it is to remember that V = IR, and think about the headphone as a single component. high resistance forces you to provide more voltage to pull the same amount of current.
3) Do I need an amplifier?
No, you probably don't. Most headphones can produce volumes loud enough to cause hearing damage with less than 20mA of current. Even the shittiest built-in amplifiers can usually produce at least 1-2 Vrms of output, which can easily pull that amount of current in most headphones.
4) Why do people say that headphone X needs an amplifier?
Because amplification is not some magical thing that just increases signal amplitude. An ideal amplifier will boost a signal by a constant ratio, proportional to its gain. People think that amplifiers work like this...
...but that's simply not true. A real life graph becomes increasingly less linear as you increase gain and output voltage. If you are pushing your amplifier to close to its saturation limit, then you are not accurately reproducing your signal.
Here is a very easy way to test what I am saying. Connect speakers to your computer. Open up a music player and set the volume to max. Now set your computer's sound card output volume to max too. If you do all this, you'll probably have to set your speakers to a low volume or the sound will be too loud. Listen to the song.
Now repeat this test, except now, set your music player to a low volume, set you sound card to a low volume, and set your speakers to a high volume. The sound will be shitty, and it makes sense, because you are amplifying with your sound with a shitty amplifier.
5) Do my headphones need an amplifier?
If you are listening to music with your headphones, you already have an amplifier. Your laptop has a built in amp. Your ipod has a built in amp. These amps work fine generally speaking, but they are still cheap amps.
The difference between cheap amps and expensive amps is that expensive amps react better when approaching saturation limits, and they also tend to have a higher output ceiling in the first place so you wont reach the saturation limit. That gives you more linear, accurate sound reproduction. Whether or not you can hear (or care for) the difference, is a different story.
If you have normal headphones, then a normal (i.e. cheap) amp is fine. However, if you buy high end headphones, you should invest in a dedicated amp of some sort, because high end headphones WILL pick up flaws in cheap amps. Expensive headphones also tend to have high input resistance and/or low sensitivity (because they are designed to work with powerful amps), so they might need more raw power.
You do NOT need an expensive dedicated amp. Old vintage receivers usually have high quality dedicated amplifiers in them. You can buy them used for as little as $5-20 on craigslist
6) I'm thinking about buying a headphone rig for my computer, do I need an external DAC?
No, you probably don't. Your source music has the largest impact on your sound, followed by headphones, followed by amplifier, followed by DAC. Upgrade things in that other. Unless you are an audiophile, the only reason why you would want a DAC is because they work externally (outside your computer). If you use your computer's built in DAC, you can sometimes pick up noise artifacts from other hardware components.
 
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Nice post. I'm not sure about the accuracy of it all, but it seems to make sense!
I'm not sure about your comment with the DAC. I would suspect that the analog output of a computer system is actually pretty poor in terms of audio quality and hi fidelity reproduction, independent of amplication capability. Some computer's may not actually be able to output 24bit/192khz either, which is perhaps more of a problem with high definition sources, than with the quality associated with up-sampling.
Additionally I'm not sure what role jitter plays with the use of a built in computer DAC c.f. using a SPDIF external DAC. USB and firewire based DAC's are able to obtain a less jittered signal if implemented well. This can make a significant difference to the sound quality. Different DAC's also have different sonic signatures which may result in a significant improvement in sound (though this tends to be a personal thing).
Either way, your sound is only going to be as good as the weakest link. The law of diminishing returns applies the more you spend. For most people a good pair of headphones and a computer is adequate. For others it won't be.
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24bit audio is a huge scam and I will go into detail to explain why
the difference between 16bit audio and 24bit audio is dynamic range. NOTHING ELSE. anybody can verify this with some googling/research. Dynamic range is basically the volume difference between the quietest sound and the loudest sound. There is a process known as dithering which means that 16bit audio can produce a perfect sound waveform, plus some amount of noise. If you make that noise inaudible, you get around 90dB of remaining dynamic range. 24bit audio follows the same principle, and ends up with 130dB or so (I forget the exact number).
Here's the problem, 90dB is loud enough to cause hearing damage from long term exposure. That means, on 16bit audio, if you volume adjust your music until the quietest sound is barely audible, then the loudest sounds will literally damage your ears. If you ever ACTUALLY listen to true 24bit audio (i.e. music that really has 130dB of range) your ears will bleed, and this is not a joke or exaggeration. In fact, if you volume adjust until the quietest sounds are readily audible (lets say, 50dB), then 24bit audio could LITERALLY kill you (170dB+ can cause instant death, not a joke, that amount of sound pressure is comparable to getting shot with a bullet).
DACs can definitely improve sound. The most significant improvements that they can offer are balanced outputs, crossfeed, and linear filtering. However, even these things offer very little change to sound quality (compared the change that you get from changing speakers, amplifiers, or source material).
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Thank you for this.
Chef is a fucking moron and his thread spews ignorance.
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Any recommendations for head phones in the range of around $70-$100? I know it's not much but, I'm frankly tired of listening with earphones all the time xx. I'm looking for one that can sound pretty good with just using an mp3 player as well.
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I'd recommend the sony mdr-v6. It's the consumer version of the sony 7506, which is one of the most popular headphones used in professional recording studios.
It's extremely neutral with good sound, portable, doesn't leak sound (can be used in libraries), and is basically indestructible, and is under $100 new on ebay.
Other options...
If you don't need portability. AudioTechnica AD700s are comfortable for most people and they have spacious sound, but lack a little bass response. Grado sr60s and sr80s are in your budget and have very aggressive sound that is good for rock, but it might be too bright/sharp for some people. They are also open headphones, which means that people near you can hear your music, and ambient noise will not be blocked out. The Alessandro MS1 is barely under $100 and its a slightly warmer version of sr60s based on my brief time listening to them (its also made by Grado, but labeled by Alessandro).
Other options include the Denon d1001 and AudioTechnica ES7 or M50. The d1001 is a good portable headphone. The ES7 looks nice and has a full-bodied sound but it isn't very neutral (sounds very bass heavy to me) and it doesn't fit comfortably for all people. The m50 is AT's studio monitor model and it is slightly warm and bass heavy, but it has good mid range reproduction. its a little bit bulky for portable use.
If you want to buy used headphones, you might be able to score Shure SH840s or grado sr225s (open headphones) at slightly over $100. They are both very high end headphones but you will need an adapter to connect them to a laptop/ipod ($10 at radioshack).
edit: all of the headphones I mentioned work fine from an ipod/laptop
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I don't really know the specific details regarding 24bit, only to say that it seems to sound better to me... Perhaps I'm just deluded.
Having said that, there are a growing number of professional sites that are offering 24bit LPCM music, and that probably means there's some benefit behind it. I'm not talking about taking a 16bit/44.1khz source and upsampling/scaling to 24bit/192khz - rather about recordings that have been originally mastered in this resolution and digitally conveyed.
The difference is probably quite subtle though.
Btw, what's your set-up?
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Baa?21242 Posts
On December 20 2009 11:48 Humbug wrote:
Any recommendations for head phones in the range of around $70-$100? I know it's not much but, I'm frankly tired of listening with earphones all the time xx. I'm looking for one that can sound pretty good with just using an mp3 player as well.
Audio Technica ATH 700s are pretty good, they go for like 110 on Amazon.
They're huge though, so portability is not a strength 
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I don't want to give the impression that 24bit audio is a bad thing. I still upsample to 24/192 for peace of mind, and regardless, technology will eventually move toward it. The thing is, although 24bit tracks truly do sound better in many cases, its not because of the format. Audio that is released in 24bit is usually mastered very well. DACs that support 24bit also tend to be high quality. For listening purposes, its perfectly reasonable to output in 16bit.
On the other hand, there is a HUGE benefit to using 24-bit audio if you are into mixing or producing music. Noise can accumulate when you layer multiple tracks. In fact, its not uncommon for recording studios to sample in 32bit depth, or higher.
My setup is Laptop -> EMU0202 -> K.I.C.A.S. Caliente -> akg k701 / grado sr225 / sony mdr v6
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United States12607 Posts
I am considering buying some headphones (HD 650s) which I have read sound much better with a dedicated amp. I really like your vintage receiver idea—my computer is my main source, how would I go about connecting it to the receiver? Is it as simple as getting a cable? Seems too easy to work, somehow
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United States12607 Posts
Also could you give me some search terms that might be useful in shopping around for an old receiver on CL? Or some tips?
Advice is much appreciated, thanks!
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Most receivers have an auxiliary input which you could connect from your computer if you really wanted to. That's what I used to do.
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On December 20 2009 12:05 Carnivorous Sheep wrote:Show nested quote +On December 20 2009 11:48 Humbug wrote:
Any recommendations for head phones in the range of around $70-$100? I know it's not much but, I'm frankly tired of listening with earphones all the time xx. I'm looking for one that can sound pretty good with just using an mp3 player as well. Audio Technica ATH 700s are pretty good, they go for like 110 on Amazon. They're huge though, so portability is not a strength
I own both ATH 700s and Sony MDR-V700s, and while the ATH 700s are a lot more comfortable (they barely pressure your head at all) the Sonys sound better imo. And they're about $80 iirc. They're incredibly tight when they're new (enough to hurt my ears after an hour or 2) but the difference in sound quality is pretty noticeable.
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United States12607 Posts
holy shit, old audio equipment is really freaking cheap on CL lol, people are selling entire CD/tape cassette/receiver packages for $50
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On December 20 2009 12:20 JWD wrote:I am considering buying some headphones (HD 650s) which I have read sound much better with a dedicated amp. I really like your vintage receiver idea—my computer is my main source, how would I go about connecting it to the receiver? Is it as simple as getting a cable? Seems too easy to work, somehow
you can use a cable and connect directly to the analog inputs for the receiver. However, this will introduce a lot of noise because you are double amplifying your signal (your laptop's headphone jack is another amplifier).
The ideal solution is to use a sound card or DAC that has a line-out outputs, which are basically an un-amplified signal. I personally use the EMU0202, because it is the cheapest USB-based DAC I could find which had the outputs I needed. It's $50-100 new, but that's still cheaper than a good sound card.
But none of that is necessary, you can just connect your laptop headphone jack directly to the receiver with a Y-cable from radioshack ($5-10), and just deal with the noise. It's not terrible noise, so its a perfectly reasonable temporary solution.
Also, if you have a home theatre system or full size stereo player, you probably already have a high quality headphone jack that you can use. Even if your player doesn't take digital input, you can just burn CD's as a temporary solution
A playstation2/3 or xbox will also work. They have lineout outputs that can connect to a receiver.
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Nice set-up. How significant is the difference when you plug the headphones directly into the computer?
My set-up is woefully incomplete and poorly thought out. My AH-D5000 is driven by my MBP. I recently purchased the Exemplar XD-1 DAC but wasn't aware that USB/Firewire would make a significant difference to jitter. Now I have to find a USB->SPDIF converter (like the Empirical Offramp). That's in addition to needing a headphone amplifier. Perhaps the only saving grace is that the Exemplar should hopefully be a better DAC than most USB or firewire options currently available, though I doubt it'll be that much better  More complex, more money, probably the same sound.
Btw, any take on the Denon AH-D5000 vs the Grado GS-1000i (it might be a potential upgrade path for me)?
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It depends on the headphone. I can't tell any major difference between amped/unamped if I use the mdr-v6 or sr225, but with k701s its really easy to tell even with matched volume levels. The only reason I use a DAC is because it has a clean line level output, which my laptop didnt have. The main reason I use the amp (as opposed to a cheaper amp) is because the caliente boosts bass response, which balances out the k701s nicely IMO
d5000s are fantastic headphones and you really shouldn't worry about upgrading, unless you specifically dislike some aspect of them. If you upgrade from there, you arent going to get much "better" sound, you are just going to get different sound. d5000s bass heavy, so maybe you like headphones with lighter bass? If that is case, audio-technica w5000s are a reasonable upgrade. If you still want high bass impact/presence, jvc dx1000s are amazing in that regard. honestly though, I would just stick with your d5000s. If you have money for gs1000s, then skipping the upgrade would give u enough cash to experiment with amps and still have money left over
Btw, I really didn't like the gs1000s when I heard them, i heard a lot of hiss and sibilance even in the vocal range, and overall they sound very different from the other grado models. I personally believe that the rs1 is the best headphone that grado has ever produced (sr225 being a close second)
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Thanks for the input.
I do like the D5000, though I haven't been able to recreate the sound I heard without a dedicated amp. The bass is a bit prominent and loose, and perhaps not as tight as I would've hoped - perhaps a reflection of the closed design. I wondered if a open design headphone would be a bit better in this sense. Re the GS1000i, I've heard it requires a significant burn in period - and certainly comments about sibilance and brightness are common.
Seems like an amp is probably the next step for me...
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On December 20 2009 12:26 JWD wrote:
holy shit, old audio equipment is really freaking cheap on CL lol, people are selling entire CD/tape cassette/receiver packages for $50
Yea, it really is a goldmine. Audio technology (other than DAC chips) has barely even advanced in the last half century, so you can find some really great deals that are still very high quality by today's standards
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Yo, I'm necroposting here because I have a couple questions I hope you guys can help me with.
I recently got the Klipsch Custom 2 IEMs for $70 shipped, and now I'm noticing a constant hissing out of my laptop headphone out jack. With my crappy earlier earbuds I didn't notice a problem, but now I sure do! + Show Spoiler [More about the C2] +Impedance is 16 ohms and sensitivity is 112 dB SPL/mW, so they are very loud and easy to drive for sound equipment of their price. They were at MSRP $200, but they're discontinued now and thus a lot cheaper. Rather than using dynamic drivers, they use dual balanced armatures. From what I read, they have a very flat (i.e. accurate) sound with good midrange, which suits me fine because I listen to mostly classical/jazz outside from playing games of course.
My laptop has Conexant onboard audio, in case you were wondering. The hissing is pretty constant, no matter if I underclock the CPU, turn off the video card, turn off the DVD drive, turn off wireless, unplug AC, etc. It's present as long as the volume is not mute even if there is no music playing, and seems to be the same no matter what volume I turn the system to.
I guess that I could get a cheap soundcard or external DAC to use to bypass the noisy laptop headphone jack, correct? If I use an external DAC (say a USB device), would it need an amplifier? Again, my IEMs are 16 ohms, and I listen to music softer than most. Just to check, volume information is sent from the system to the DAC, correct? So I could change laptop volume, and it would send a different-volume digital signal to the DAC to go to the 3.5mm headphone plug to the IEMs.
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