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Old 11th February 2013, 03:28 PM   #34801
qusp is offline qusp  Australia
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Quote:
Originally Posted by fas42 View Post
Well, you've got me going now ... had a look over at HeadRoom: Headphones: Full-Size, In-Ear, Wireless, Noise Cancelling, Headsets at what they show, AKG 272HD vs. HD800 - same methodology in testing always gives one a head start (is there a pun there?) ! Everything there points to the Sennheiser being superior: flatness of FR, distortion, square wave handling, impedance load is an absolute doddle ... so what's going on?

The clue is the FR: the AKG's fall off a cliff at about 2kHz ... all the nasty high frequency stuff is nicely pushed into the background - apart from the massive 15dB spike at 10kHz, I wonder how a speaker with that sort of performance would go down ...

Frank
Whatever Frank, your full assessment without any first hand knowledge, or it would seem going by your take on a weekend with the HD650, without a proper headphone amp; doesnt hold much water as to your opinion on what myself and others are hearing. Continued theorizing by google does not strengthen your case.

The spike at 10K is an artifact of the test rig, its there in just about everything at headroom. i'm not pro AKG242 MkII either really, but I would take them over the HD800. The HD800 is part way to a nice and very comfortable headphone (if you can get past what you look like with them on), it does many things very well.

The first time I heard them I thought they were quite impressive, but over time with more experience with them, the overtly large stage along with the mind exploring mid/treble became apparent to me and now its all I hear. They are very picky as far as amplifier, most seem to enjoy them with tubes, probably due to having more damping in the electronics to offset some resonance in the driver, construction or impedance. Several mods have come about to battle the resonance I speak of, as well as a quite ridiculous one where a set of HD600 are worn at the same time as a set of HD800 over the top (both are open back) you should read Tyll's review of this hehe! hilarious!

aside from soundstage size, my JH13 (custom in ears with passive 3 way 6 driver WW-MM-TT crossover) are better at everything they do for my taste. They are much more nimble, with STAX-like transient speed, more detail, nice tight and well extended bass, very good imaging, excellent and fairly neutral midrange, yet without the fatigue. they have a small bump at ~40-50hz (with extension down to 15-20Hz), but are otherwise quite neutral as are built to be Custom in ear stage monitors.

Each set of JH13 is equalized (to a target curve) due to every set and every ear cavity/'room' response being different. they use the ear impression used to create them, along with computer modelling and measured response to meet the curve for each set of headphones crossover. This is termed 'ear flat'

there are now a couple versions of stage monitors with digital crossover/correction and are paired with a multichannel DSP->DAC->AMP with 6 wire headphone cables (actually from memory they were disappointingly a 4 wire a side with a shared ground)

for the money needed for a decent HD800 rig i'd rather just go the extra mile, get some STAX and build a DIY T2, KGSS or BHSE. But I became distracted with speakers....

I do not believe you can get a great idea of how headphones will sound by plots just yet, you can get some idea of how headphones may compare to one another, so i'm glad the search for a proper measurement technique is ongoing.

Last edited by qusp; 11th February 2013 at 03:47 PM.
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Old 11th February 2013, 03:30 PM   #34802
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I use ferrites araound all my audio cables, including speakers. What's the hell ?
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Old 11th February 2013, 03:36 PM   #34803
DF96 is offline DF96  England
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There are lots of different ferrites for lots of different purposes. Also iron dust cores which some may confuse with ferrites. Use the right core and it helps keep RF out of your equipment. Use the wrong one and it could help inject RF into your equipment by tuning your cables to make them better antennas!
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Old 11th February 2013, 04:00 PM   #34804
qusp is offline qusp  Australia
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actually here Frank, Tyll has documented and collected all of the mods to address the problem I speak of. the most well known of which is the 'Anaxilus mod' after the head-fi member. waterfall plots seem to reveal it best.

Quote:
"...the main effect of the mod is the reduction of inner reflections, the reduced treble intensity is the result of reduced parasitic transient corruption"
Quote:
I believe the metal ring around the driver is acting acoustically as a reflecting surface and helping to promote a resonant mode that is storing a bit of energy. It is this very slight ringing at 6-8kHz, I believe, that some people find objectionable.
and I do...(underline mine)

thats it on headphones from me, sorry chaps.

Last edited by qusp; 11th February 2013 at 04:03 PM.
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Old 11th February 2013, 04:19 PM   #34805
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There are lots of different ferrites for lots of different purposes.
I had not made any comparizons. Bought ferrits and mounted them. Nothing changed in the 200K Hz range, little rounding of square waves, reduction of HF noise, not a big change in tonal presentation, just the signal is cleaner: i can live with, or without.
I doubt any big changes due to the Q of various ferrites, considering the involved inductances. Am-i wrong ?
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Old 11th February 2013, 04:19 PM   #34806
marce is offline marce  United Kingdom
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True, you have to match the ferrite to the problem (the noise that is of concern) though the clip on ones are quite often broadband (25MHz - 100/300MHz) and I would suspect that these are the most frequently used as they are the 'standard' or basic clip on most of us are likely to buy. Operating at frequencies though of a magnitude of 1250X the hihest audio frequencies are they (rf aside) going to affect the audio waveform, and if so by how much?
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Old 11th February 2013, 04:25 PM   #34807
SY is offline SY  United States
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Originally Posted by marce View Post
(rf aside)
That's one big "aside"!
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Old 11th February 2013, 04:40 PM   #34808
DF96 is offline DF96  England
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Three possible effects of ferrites on cables:
1. modify (hopefully downwards) the amount of RF entering the equipment
2. affect stability (but only on equipment which was almost unstable anyway)
3. add distortion (but only when used wrongly e.g. separate ferrites on signal and return wires so saturation possible)

Less RF ought to improve things, but some people may prefer extra noise and distortion so injecting RF via badly designed cables etc. may please them.
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Old 11th February 2013, 04:54 PM   #34809
Bonsai is offline Bonsai  Taiwan
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A ferrite bead can also work wonders. In an EF2 or EF3 in the base of the diver they absolutely kill any HF parasitic oscillation. Wonderful devices.
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Old 11th February 2013, 04:59 PM   #34810
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May-be we can start a business of special audiophile ferrites, with rare earth, precious metal plated, with some nice wood cover to dump resonances (of course) witch will add purity to our music ?
With the advantage we could produce real impressive curves (in the Ghz range) to justify the amazing improvement, ( a little obscure technique help ), and nice poetic words to share comparative listening impressions, in the spatial area, separation, fluidity, easiness of transients and natural of the reproduction.
Of course, they will be VERY expensive, and w'll have to pretend their improvements only reach the top on HI-FI (not MID-FI) equipments around. While they will help any system, no way to lose a market.
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Last edited by Esperado; 11th February 2013 at 05:07 PM.
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