milkpowder

I also wonder how it works. I'm guessing the iTransport has AAC, MP3, ALAC to PCM decoders built-in in addition to its ability to read/interpret the iPod file structure. A S/PDIF converter and DAC then output coaxial digital and analogue, respectively. You would then be able to use your DAC of choice with your iPod achieving eargasms limited only by the size of one's wallet (whatever is left of it!)

Wikipedia has a decent explanation too. I also thought this was pretty informative: http://www.6moons.com/audioreviews/balance...phones/one.html I have never ever tried balanced Grados nor recabled ones. Quite a few companies will recable your Grados though: Moon Audio, APureSound, Headphile, etc. The stock Grado cable is a decent OFC so the benefits of recabling it is questionable. Maybe it could use higher purity conductors, different materials (OCC copper, silver, gold, or even carbon fibre), better insulation, etc, but who knows whether the sound signature will change for the better or worse? Unfortunately, my lack of experience in this area means that I can't offer any solid advice. I've read that too, but I really question whether it would really make a huge difference. A lot of cheap so-called balanced sources aren't really utilising fully balanced internal circuits anyway (balanced output signal converted from single ended signal through the use of either a transformer or phase splitter circuit). I'll refer to what Tyll Hertsens of Headroom Corporation said about balanced drive: Many pre-amps that have bothe balanced and unbalanced inputs and outputs contain a phase splitter. This circuit is designed to take an unbalanced signal and make it balanced. A tranformer could be used here, but more commonly a phase splitter circuit is used. This circuit contains at its heart an inverting amplifier that takes the unbalanced signal and inverts it to make up the "-" signal. The problem is that the normal non-inverted signal does not pass through this amp. What happend is that the inverted "copy" of the normal signal is slightly different because it has passed through the inverting amp. When we're talking about achieving high levels of performance with this technique, ANY missmatch between the two signals is a definate no-no. Many of the very competent technical arguments against balanced drive (PPLs for example) contain a disgust for using this "phase splitter"---a disgust which I share. I believe there is only one way to do balanced right which is by starting with a balnced signal and then keeping them perfectly matched (as humanly possible) through-out the entire signal chain. The only way I know of to do this is: getting a signal from both sides of the coil in a phono cartridge, microphone, ot tape head, and by having two digital to analog converters for each of the left and right channels one outputting the normal signal and the other a numerically perfect inverted signal. ANY other method for creating a balanced signal for a single unbalanced signal will create a non-perfect copy, and therefore significantly minimize the benefits of balanced drive.

Headroom gives a nice, easy-to-understand run-through: Standard headphones have three electrical connections: one to each ear and a common ground wire. The audio drive signal goes to one side of the driver coil in each earpiece, and the return from the coils joins together in the common ground connection. In balanced headphones both sides of the driver coil are driven simultaneously and no common connection between channels exists. Therefore, balanced headphone amplifiers generate a normal and a perfectly inverted audio signal. The inverted signal is basically a mirror image of the normal drive signal; so when the 'normal' signal is going positive, the inverted signal is going negative in an identical sine-wave relationship. In brief, this complex method of driving headphones effectively doubles slew rate, voltage swing, & power output, and halves the output impedance of the amp as seen by the headphones. The result is a dramatic improvement in audio quickness, musical clarity, and sonic impact. I also believe balanced connections are basically immune to RF interference.

Nordost uses something similar on their top-end cables and so do Tara Labs on their midrange cables. It's basically increasing the volume of air around the conductor, dramatically reducing the dielectric constant and increasing propagation speed. I personally haven't used cables which aggressively advertise their use of air dielectrics and neither can I see why it would make a dramatic improvement on the sound quality.

Out of a good amp, all the "darkness" disappears. I'm really not joking. The HD650 (and the HD600/580) are top-notch cans that can sound absolutely incredible with a well designed amplifier. Don't forget a good source too

There are quite a few headphone forums though. Head-Case.org tends to be where a lot of senior/experienced Head-Fi (or ex-Head-Fi) members congregate. The language is much more brutal (as you will see for yourself) but the discussions are usually very high end. There aren't many noobies around at all. Having joined Head-Case.org for a few days, I've gathered that they really don't like Ray Samuels and many members have issues with the way Head-Fi is run/moderated.

I'm assuming you've tried contacting Justin directly, or does it have to be a post on the MOT thread?

Hmm distorting on iTunes... I had that problem when I over-boosted certain frequency ranges in the EQ panel. Does it distort when the EQ is off or configured at 0dB?

Just comparing the XRCD version of Jazz at the Pawnshop to standard redbook, the XRCD does indeed sound more lively. XRCDs (XRCD -> XRCD2 -> XRCD24 -> K2 HD) are superior to CDs because they are mastered at higher specs. The final CDs are also physically better made. Technically, the XRCD versions will be closer to the master tape. cmk is completely right though. The proof of the pudding is in the eating.

Looks hardwired.

I did my A levels in the UK, but really don't think my syllabus had anything about semiconductors in it! We did the standard quantum stuff, eg wave superposition, two slit interference, quarks and bosons and other subatomic particles, etc... Sg A levels are probably much more advanced though. Honestly, I'd be lucky if I still remember any of it. EDIT: actually band theory sounds very familiar. I remember it having to do with tubes:D

Haha, the infamous electron configurations. Worked for a while, but once we touched on orbitals, everyone was either confused or mad about why we were basically lied to. The 2,8,8, etc explanation is extremely limited, just like the oxygen definition of oxidation. Works for the simple stuff, but insufficient once you touch on anything vaguely advanced.

It really depends how much you'd like to spend. Judging by your gear, I'm thinking you wouldn't mind dropping USD$150-300 on a set of decent cables? There are so many reputable cable companies out there... Nordost, Chord, Transparent, Audioquest, QED, Van den Hul, Cardas, Wyrewizard, PS Audio, Harmonic Technology... gosh I could go on forever All of those companies have cables in the $150-300 price range. Of course, there are also smaller cable maker companies like Signal Cable, Blue Jeans Cable, Better Cables, etc... Get whatever looks good

Also check to see if you can get updated sound card drivers.

Ahh... cotton is supposed to have an even lower dielectric constant than Teflon! I'm not sure about silk though.

Just looking at what audio cable manufacturers use for insulation, Teflon is the most commonly used insulator because its dielectric constant is almost the lowest of any man-made material. Yeah. On cheaper cables, you'll find mostly polyvinyl chloride or polyethene. On more expensive cables, air and vacuum are the very best. Companies like Nordost use micro-filaments around the conductors to increase the volume of air and then encase them in Teflon tubes. Tara Labs also uses air insulation but goes right to the extreme with their top-of-the-line cables, attempting to do away with the insulation as much as possible with their vacuum technology.

Teflon is used because of its extremely low dielectric constant. My very elementary understanding of what that means is that it does not store a lot of electrical energy relative to what a vacuum would store if you were to apply the same potential difference. By definition, a vacuum has a dielectric constant of 1. Air is just a tad higher than that whilst Teflon is about 2.1 or so. A bad insulator would literally soak up energy from the cable. Here endeth my knowledge...

Here goes my last off-topic post in this thread: Oxidation/reduction is formally and scientifically defined by change in oxidation numbers. Sure, oxygen may be involved in some, but not in all redox reactions. Exchange of oxygen is an unsatisfactory and elementary definition of oxidation/reduction. BTW, I am also relying on my high school A-level chemistry

Jude: 2007-11-13 0857 EST This is obviously our worst outage in the history of Head-Fi.org. What happened was that we had Head-Fi.org's files and backups moved to a multi-terabyte network attached storage (NAS) unit while we continued to work on the proper implementation of a true clustering configuration for Head-Fi.org. From what we can tell, this particular NAS unit--with a reputation for being ultra-reliable--had one of its 12-channel RAID controllers malfunction. This particular NAS unit is a 24-drive unit, made up of two 12-drive arrays, each array with two parity drives (RAID 6). Maybe we put too much faith in it, but we thought were safe housing everything on it for the time being. From what we're being told, when the controller card malfunctioned, it messed up the NAS unit's logical volume, which is where we're at now. We are working closely with the vendor and the technical support team in Europe to restore the logical volume and get the NAS back up again. We feel confident we will be able to restore Head-Fi to its state just before its outage, but won't know for sure if we'll have to fall back to a back-up, of which there are many on the NAS. Unfortunately, the only off-NAS backups we have of Head-Fi.org's databases are quite old, meaning we'd potentially lose thousands of posts, so I will not put Head-Fi.org back up until we know for sure the status of the logical volume restoration. The repair was well under way yesterday when the repair process ran out of RAM. (The NAS has four gigabytes of RAM.) Since, for a number of reasons, the repair process was being run almost entirely from RAM, the four gigs was apparently not enough. I have ordered 16 gigabytes of RAM, which will arrive this morning, immediately after which I will head to the datacenter to install it; then the team in Europe can commence with the remotely administered repair process(es). The repair has gone slower than we anticipated, and running out of RAM yesterday was an unfortunate setback. But, once again, 16 gigabytes of RAM (versus the four gigabytes in there now) should be arriving this morning. whereupon we will immediately call our friends in Europe so they can continue with the repair work. We already know some data was lost, but hope and pray that what we do retrieve will be enough to let us get the site back up this evening. We know we should have been more diligent about keeping more backups off the NAS, but running two 12-drive arrays, each array in RAID 6 (two parity drives, for a total of four)--and the fact that our previous, self-built NAS units ran without problems for over seven years--we felt we were safe in keeping them there until we were finally through with the proper clustering we've intended for months. All I can do at this point (other than what we're doing above) is to apologize to you all for the outage. Though Head-Fi isn't what I do for a living, it is very important to me as a gathering place for friends, and I know it is for many of you, too. Once again, I'm sorry about this extended outage, and will continue to work on it until we're back up (hopefully tonight).

Note that I put inert air in quotation marks. Of course I know there is no such thing as inert air. It's part of Nordost's BS marketing literature. I am well aware that even some of the most inert elements (eg gold) can be made into compounds under the right conditions. About silver oxidising in contact with air: Oxidation can mean an increase in oxidation state so your rash statement about the word "oxidation" hinting at what caused it is partially incorrect. Technically, silver doesn't form oxides in normal atmospheric conditions. What it does form, however, is silver sulfide, Ag2S The reaction can be summarised as such: 2 Ag + H2S => Ag2S + H2 The oxidation number of silver on the left hand side is 0 as it is in elemental form. After reacting with H2S in the air, its oxidation number is now +1. An increase in oxidation number equals an oxidation reaction. Technically, this is a red(uction)ox(idation) reaction because hydrogen goes from being in +1 oxidative state to 0. Sulfur's oxidation state remains constant at -2. I hope that justifies what I've said. Peace.

Like you said, it is impossible to keep the silver wire suspended in the middle of the insulator on its own. However, with the help of an additional spiral of filament around the conductor, this is definitely possible. Just look at Nordost's higher-end cables. They all boast mono-filament or dual-mono-filament technology, most recently patented and developed by 3M in 2005 (US patent no 6,849,799). The helically wound spacer (or filament) creates air voids, suspending the central conductor in air - the best dielectric 2nd only to a vacuum - and effectively lowering the dielectric constant of the cable. As a result, propagation speed increases. This technology has actually existed since April 1936 (US patent no 2,038,973) invented by Jesse F Wentz of Bell Telephone Laboratories. Wentz used a dual filament of acetylated cotton around a copper conductor, which was then wrapped in iron tape and encased in a lead sheath. It's sulfur in atmospheric air that causes the 'oxidation' or 'tarnishing' of silver. During the manufacture of a cable, I'm sure it is possible (don't quote me on this ) to purify the air in a way that all the potentially reactive components are removed, hence leaving you with "inert air".

Haha. Actually some person I spoke to didn't like the Jena cable. His reason was the Jena Labs recable made it sound slightly harsher than before. A quick listen confirmed his observations. The K701 was faster and more responsive than before and that might give the impression that it is harsh. Personally, I'd have to do a more extensive comparison first. It would be in your best interest to buy an additional pair of re-cabled K701 for comparison purposes

Was just reading the specs on the page linked to by Nu_Omega and noticed how weak the speaker amp function of it is: 240mW into 8 ohms. What speakers could you run with it? It would be too weak even for ultra-efficient Avantgarde horns unless you listen to them in near-field setting! Certainly wouldn't be able to drive K1000s properly. Interesting headphone amp nonetheless.

I've heard the K701 (stock and recabled w/ Jena Labs) driven out of a SP Platinum Extreme and Meridian G08. Great sound. The headphone amp of the DAC1 (recent revision) and Graham Slee Solo sounded pretty good with the K701 too.

Nope. I hope to do so at the next opportunity. I noticed I used past tense when I meant to say: I wonder how the E9 compares to it. Apologies for the muck up.