[Trae]

I guess I'll chime in on how a DAC works:
 
It converts a digital signal into an analog signal, basically. The digital signal is generally received through any digital interface like USB. Depending on the specs of the DAC, it will be able to support a variation of samplerates (44.1KHz, 48KHz, 96KHz, etc.) and bitrates (16bit, 24bit, 32bit). The higher the bitrate and samplerate, the better quality the signal there is. I read somewhere that listening to 24/192 is actually bad for your ears, though... Also, different DACs have different SNR (sound to noise ratio). The higher the SNR is (measured in dB), the more resolution the DAC will have because you will be able to achieve a higher volume without hearing any hiss (noise from the source equipment). For example, here is a graph of some DACs and their respective SNRs (Courtesy of Audio-gd):
 

 
I'm sure some of you have heard of Wolfson DACs, and how they're so great, and this is the main reason why (the Wolfsons are the WMxxxx). They're able to achieve a high SNR while supporting a wide array of bitrate and samplerate formats. I'm also sure some of you have heard some DACs or DACs/Amps using dual Wolfson DACs, and that's because some of them are only able to convert one channel, like the WM8741. So, you'll need two of them in order to have both channels converted into an analog source for the amplifier to amplify. You want the highest SNR possible from a DAC so that the noise generated from the DAC + the noise generated from the Amp will be as little as possible. 
 
About 90% of the world uses CD quality audio (44.1/16), so the crazy formats that some of these chips support will be useless, unless you that 10% that uses 192/24 (more like 2%). You may think upsampling them will make them sound better, but that's like converting an MP3 128kbps into Flac. It's pointless, and it may even lower the audio quality in the process. So, you're better off not touching anything in that area. 
 
Well, that's about all I know on DACs. 
 

if you had a 4/5/5.5 gen iPod video you could send it in for an iMod. They replace the DAC and re-route the line out to bypass the internal amp, and recase it so there's no hp out, just line out.

I dream of owning a Super iMod (home modded with a 240gb HDD)

 
They don't replace the DAC, they just reroute the signals right after the traces leave the DAC, thus completely bypassing the amp. The 4th gen rewires the headphone out as a line out, and the 5/5.5 gen rewires the dock as a line out, while retaining the functions of the dock. 

 

[chuckle490]

Bravo Trae, very informative and much appreciated.

 

[Trae]

Quote:

 
 
Anyone?

DT770 pro250 + amp will sound better than DT770 pro80 without an amp, especially if you're a basshead. With an amp, you will have more volume overhead, and more room to eq the bass out before it starts distorting. The best setup would be the pro80s with an amp because they're more sensitive, and they should scale better, volume-wise, with a good amp.  

 

[Jlox1]

Quote:

 
Well, I love the look of Ultrasone cans, so I'll take one out anytime.
 
 
The SRH750DJ isn't a really big circumaural can for me. It's the norm in size, but there are definitely bigger, "portable" cans out there. Take a look at the M50, for one.
 
 
As I mentioned earlier, I haven't heard the HDJ-1500, but I love my other Pioneer cans (500, 1000, 2000). They are generally detailed sounding, with a good bass punch. Bass quantity goes down and sound quality goes up as the model numbers increase. I suppose the HDJ-1500 would be an intermediary between the HDJ-1000 and HDJ-2000, 2 cans which are already quite difficult to separate in terms of pure sound quality. If you can get a decent price on the HDJ-1000, you should just get one.

Yeah I was asking about the 1500s so religiously because on amazon right now the 1500 is going for 145 new while the 1000 is going for 149 new.

 

[Apo0th3karY]

Quote:

I guess I'll chime in on how a DAC works:
 
*snip*
 
They don't replace the DAC, they just reroute the signals right after the traces leave the DAC, thus completely bypassing the amp. The 4th gen rewires the headphone out as a line out, and the 5/5.5 gen rewires the dock as a line out, while retaining the functions of the dock. 

 

 Thanks for piping in where I'm still useless lol.
 
Hmmm... I thought during the iMod process they put in a Wolfson chip and bypassed the internal amp.... what do I know Either way whatever they're doing it's a 200x improvement from stock.

 

[DexterMorgan]

A low cost deal for bassheads: JVC HAM5X for £21.67 at amazon.co.uk. http://www.amazon.co.uk/gp/product/B004W73TCI/ (this is the lowest price for this headphone in Europe, ever, I think)

 

[Prakhar]

I wonder... The new Ipod touches and iphones have a lightning dock that is digital out only. To use LODs you need an analog out. The adapter that apple offers has the Wolfson DAC built into it. 
 
Doesnt that mean that using the adaptors with the new ipods and iphones will give a true line out?

 

[Trae]

Quote:

 

 Thanks for piping in where I'm still useless lol.
 
Hmmm... I thought during the iMod process they put in a Wolfson chip and bypassed the internal amp.... what do I know Either way whatever they're doing it's a 200x improvement from stock.

No problem. I forgot some stuff too. I need some time to research it and fully understand it before posting it, though. The reason why iMod is available only on the 4th, 5th, and 5.5th gen devices is because they use Wolfson DACs in them. They're reportedly better quality DACs than the Cirrus DACs they're using in the 6th and 7th gen. That's why they don't iMod those generations. 

 

[Trae]

Quote:

I wonder... The new Ipod touches and iphones have a lightning dock that is digital out only. To use LODs you need an analog out. The adapter that apple offers has the Wolfson DAC built into it. 
 
Doesnt that mean that using the adaptors with the new ipods and iphones will give a true line out?

 
Wow, I didn't know that. I did some reasearch, and they use the WM8533 DAC that supports up to 192KHz. Buy the new touch with the adapter, and the L9 and see if it works!
 
EDIT: It works, according to this post I found on Amazon. It would be kind of hard using it for portable use, though. Two adapters stuck together along with an amp sounds like a disaster waiting to happen. Put it in your pocket wrong and snap!
 
 
 
Alright, here's the other part: THD and the Dynamic Range
 
THD= Total Harmonic Distortion. This is the distortion that the equipment gives off. This applies to DACs, amps, and speakers. Every piece of equipment will give off some distortion. This isn't the distortion that you hear when you blast the volume up too high. This distortion is already implemented in the sound after the signal has been converted to an analog signal, or when the analog signal is amplified. Think of it as a byproduct of converting or amplifying the signal. You don't really have to worry about THD because most amps and DACs' THD is so low, it isn't recognizable by the human ear. In order to save my fingers some button pushing, I'll just throw this quote in from bcae1.com:
Quote:

When an amplifier is driven with a signal, the signal at the output terminal of the amplifier is an amplified version of the input signal PLUS any distortion created by the amplifier. All amplifiers and signal processors add distortion to the signal. The levels of harmonic distortion in a high quality amplifiers are sooooo far below audibility that they are basically of no concern. When someone tells you that one amplifier is definitely going to sound better because its THD is rated at .002% vs an amp with .05%, you can be pretty sure that he doesn't know what he's talking about. Many people believe that THD below 1% is not audible and I believe they're probably correct. The fact is, especially in an automobile, the amplifier is the least of your worries. Speakers used for mids and highs commonly produce between 1% an 5% THD and for subwoofers the numbers can easily reach 10%. This doesn't even take into account all of the resonances of all of the plastic and metal panels in the vehicle.

 
Total Dynamic Range is a bit trickier to understand. For DACs it's the range, in dB, that it supports without distorting. For example, the Wolfson WM8533's dynamic range is -100dB (quietest) to +12dB (loudest). You add those two numbers together, and the total dynamic range is 112dB. The DAC is able to support a file that is within those boundaries without distorting. The music file's themselves have a dynamic range too. The reason is because if you didn't have one, there wouldn't be any audio. Different mastering companies use devices that master the songs at different dynamic ranges. That's why some songs sound louder than others. Plus, some people tend to edit some songs and apply some gain to it to make it sound louder. If the music file's dynamic range is +13dB, then you will hear distortion because it exceeds the dynamic range that the DAC supports (I'm talking about the WM8533). Keep in mind that +12dB isn't that loud, but that's when an amp comes into play. Keep in mind that if you have a 13dB (using the WM8533 again here) file that has been converted into analog, and then amplified, it is still going to sound distorted because it exceeds the supported dynamic range. Amplifying it will just make it even more evident. This video may also help you understand dynamic range. 
 

 

[Apo0th3karY]

Quote:

Quote:

 

 Thanks for piping in where I'm still useless lol.
 
Hmmm... I thought during the iMod process they put in a Wolfson chip and bypassed the internal amp.... what do I know Either way whatever they're doing it's a 200x improvement from stock.

No problem. I forgot some stuff too. I need some time to research it and fully understand it before posting it, though. The reason why iMod is available only on the 4th, 5th, and 5.5th gen devices is because they use Wolfson DACs in them. They're reportedly better quality DACs than the Cirrus DACs they're using in the 6th and 7th gen. That's why they don't iMod those generations. 

 
Ah. I get it now.

I know the Wolfson DAC is superior, but I've come to understand the Cirrus chip isn't far behind though. I dunno I checked this stuff out briefly before I joined the forum and haven't really kept up with it and just been happy with my iPod. I figured if I don't look more into it, I won't want to upgrade.

Actually I had a eureka moment earlier today as I realized that my 2G 64gb iPod Touch that I haven't touched (pun intended) since the left channel of the hp jack went out. I got a 3G 32gb to replace it and it's not holding enough, and I'm rotating music and I've resorted to the iPod 'compression' that I don't fully understand. This is all waaaayyy OT though. lol

 

[clarkkent]

Subscribed!  Now to try to read this gigantic thread lol...

 

[clarkkent]

Saw this in the deals thread
Quote:

Philips Citiscape Downtowns in white @newegg.com for $39.99, free shipping.
 
http://www.newegg.com/Product/Product.aspx?Item=9SIA0MC0KX8289&cm_sp=Spotlight-_-9SIA0MC0KX8289-_-01152013

 
I do like tons of bass lol.  I have some JVC S500's coming, but I'd like some "fun" bass heavy headphones as well.
 
Is this philips a good choice at $40?  Some amazon sellers are still selling the XB500 for $67 shipped, is it worth it to step up to those?  Or do you have any recommendations for under $75?
 
Thanks all!

 

[miow]

Quote:

A low cost deal for bassheads: JVC HAM5X for £21.67 at amazon.co.uk. http://www.amazon.co.uk/gp/product/B004W73TCI/ (this is the lowest price for this headphone in Europe, ever, I think)

 
Do they sound any good? I've just ordered one since it's so cheap.

 

[dimitri42]

Quote:

 
Do they sound any good? I've just ordered one since it's so cheap.

 
I would like to know that too. I might try them out.

 

[Prakhar]

RPG has a reivew on them I think... Check it out?