[Deiz]

Quote:

Originally Posted by effectic /img/forum/go_quote.gif Hmm explain something to me then. a HD600 sennheiser which is 300ohm obviously requiring an AMP. Why would it require an AMP? And without am AMP what will the result be? Lower volume or lower sound quality? Meaning by a significant margin would the average joe who aint audiophile actually notice it in a blind test?

Impedance is only half of it. Sensitivity is very important. At 1 mW, HD600s will output 97 dB, contrast this to a pair of SR80s which will output 98 dB at 1 mW.
So they'll be almost identical out of a headphone jack, right? Wrong. The SR80s have a 32-ohm impedance, and will output roughly 111 dB out of an iPod, which is 30 mW into 32 ohms. Given that to double the output, you must double the wattage, 1 mW is 98 dB, 10 mW is 108 dB, and 30 mW is 30% of the next 10^n, we can add 3 dB, coming to 111 dB.

On the other hand HD600s, with their 300 ohm impedance, present a tougher load, as impedance isn't completely linear they'll get around 5 mW out of that same 32 mW-into-32-ohms headphone jack. Thusly, 97 dB + 40% of doubling = 101 dB, exactly half the output level of the Grados that, ignoring impedance, were only ten percent louder before.

When you increase the impedance, the amplifier needs to be able to swing more voltage. Inversely, low impedance headphones need lots of amperage.

When the headphone amplifier can't supply the voltage or amperage necessary to drive the headphones, you're hearing less than ideal, amp-limited sound.

The thing is, a line level signal is more than enough to blow out headphone drivers. On the other hand, with a line level signal, the most sensitive of speakers will barely make a peep. A power amplifier for speaker therefore amplifies line level to speaker level.

On the other hand, the main purpose of a headphone amplifier is to provide either high amperage or voltage to a difficult-to-drive load, at comparatively tiny output levels, as compared to speakers.

So, in practice a headphone "amplifier" tends to actually be attenuating a line level signal, in the most basic sense - But it does this more elegantly than the other solution: Placing coupling capacitors and passive attenuators on line-level outputs from your source.

 

[Fidelity_Fiend]

Quote:

Originally Posted by effectic /img/forum/go_quote.gif So will be interesting if someone can compare the Z5500 amp with an expensive amp with a high ohm headphone and see if it can power it with low distortion. Atleast compared to the average human ear, many people claims to be audiophiles however after years of damage to your ear drums because going deaf with headphones is very likely and almost unavoidable. I doubt many of us can even hear the difference between real audiophile equipment. Most scientists agree a lot of things are also all in your mind and its a psychological thing with your brain tricking you. Who knows they could have a point also scientists agree burn in is just a myth to even to this date they continue to preach burn in is all myth and we only think it works cause our brain and ears adjust to that specific sound signature. Who knows?

Two things:

Firstly, hearing damage by headphones is by no means inevitable and it would be foolish to except it as such. It is true that it is easier to damage your hearing with headphones but sensible use will prevent this. Most of the hearing damage publications refer to masking, where someone turns up the volume of their headphones in order to drown out background noise, especially when using headphones that are not noise blocking such as earbuds.

If you listen to headphones in a quiet environment where there is no noise to mask, at a prudent volume then there is little risk. No true audio lover would be willing to risk their hearing. I think boasting about speaker sessions 'louder than a jet engine' are probably what brings the tinnitus. Just for the record, 130db will damage your hearing almost instantly. The exposure guideline for;
115 dB - .46875 min (~30 sec)

That's as high as the chart goes but for every 3db over 85db the safe exposure time is cut in half. So take the above figure of 30 secs and reduce it by half 5 times. Meaning that the exposure time to 130db before serious risk of hearing damage is 0.9375 seconds.

Secondly, while the burn in of electronics may be debatable - actually the term originates from the burning in of vacuum tube electronics. While it maybe be exaggerated, burn in with drivers makes perfect sense. Drivers will become more supple after a lot of motion, it simply makes mechanical sense.

 

[Dominat0r]

or you could of saved the science lesson and just plug your cans into a real headphone amp and your ears will tell you the difference. You quickly learn that amps just dont provide volume. However, now you know how it works, and KNOWING IS HALF THE BATTLE!

Honestly....ignorance is bliss...if it sounds good to you, then dont fix it =) You will find yourself in a never ending spiral of gear trying to find that perfect sound....takes a lifetime and a whole bank account to do so.

 

[eruditass]

Quote:

Originally Posted by effectic /img/forum/go_quote.gif Thanks for explaining it like that for me guys finally someone explained it the real scientific way. Now I have a perfect idea on the importance of headphone AMP. This is why I like head fi folks people here actually have electrical degrees and stuff and I am a person always listens to a man who speaks science. I find they should make Deiz post a sticky. Ow and Fidelity_Fiend to. I think we have all learned a valuable lesson here today, that education and science is very important in life else we would have 0 understanding of anything.

in addition to power, there are many things that come into play such as transient response, crosstalk/stereo separation(something commonly overlooked, and the reason why many people don't hear soundstage), harmonic distortion, intermodulation distortion, frequency response, and phase response.

 

[Shahrose]

Quote:

Originally Posted by chef8489 /img/forum/go_quote.gif I run z5500 and will defently tell you the headphone out is lacking. The speakers sound great but not enough power out of the headphone. Love the pico dac as I get a much better sound.

i tried the z-5500 headphone out (i don't even think it's actually amped) and all it did was reduce the volume of the output and made the quality slightly worse. you're better off plugging the headphones directly into your soundcard. to be fair, no computer speaker headphone-out is good, so the z-5500 is not alone.

 

[fubarbundy]

Just to wake up this thread and give a definitive answer - the headphone amp in the Z-5500 is APPALLING. It chops off all bass frequencies (maybe below ~100Hz) from S/PDIF at least for no apparent reason - well above what goes to the sub (~30-35hz).

 

[crapback]

It does fine producing white noise for burning in a set of 990's.

Other than that it sounds boxy and narrow out of an x-fi extreme gamer. Adding the crystallizer just made everything artificially bright. It will go unfreakinbelievably loud though. Always remember to not turn down the volume before you unplug your headphones. If you do you might not get to enjoy shocking the bejeesus out of yourself and anyone else within a 1 block radius.

 

[ben_r_]

So, was there any out come to this? I have owned the Z-5500's for about four years now and have often thought of putting an CMOY in line with the headphone out. Is that not advisable? Or should I get a Y for the front channel out from my X-Fi soundcard and plug a CMOY in line with that. Just looking to drive maybe a set of HD-280's.

 

[dye1337]

the output on the z5500 cant properly power sr80s, let alone an hd600.  Sorry, I even tried it out with hopes, don't hold yours up.

 

[dizzyraider]

Quote:

So, was there any out come to this? I have owned the Z-5500's for about four years now and have often thought of putting an CMOY in line with the headphone out. Is that not advisable? Or should I get a Y for the front channel out from my X-Fi soundcard and plug a CMOY in line with that. Just looking to drive maybe a set of HD-280's.

 If you have computer>Z-5500>CMOY, then all you would do is amplify the distorted sound from the Z-5500. I would just have the cmoy directly connected to the sound cards's line out.

 

[D4ydream3r]

I just received my brand new set of DT770 250ohm. I quickly plugged it into my Z-5500 and currently playing Chamillionaire - Ridin 192bitrate  at "Boost 5". It powers my cans just fine unlike my friend's 600ohm AKG K701s, I can turn it all the way up and still feel underpowered. I also order a FiiO E5 portable amp, will compare and update once it comes.

 

[colmustard]

Quote:

I just received my brand new set of DT770 250ohm. I quickly plugged it into my Z-5500 and currently playing Chamillionaire - Ridin 192bitrate  at "Boost 5". It powers my cans just fine unlike my friend's 600ohm AKG K701s, I can turn it all the way up and still feel underpowered. I also order a FiiO E5 portable amp, will compare and update once it comes.

600 ohm k701!?!?! 

 

[Mr. Morden]

I wouldn't recommend the Z-5500's for headphones. Maybe mine have a bad jack, but if I plug in any headphones (Be they my ATH-M50s or cheap Apple buds) they distort HORRIBLY if there is any bass. It's universal across the headphones, I tried my RE0's, then my M50's and all of them did it. I plugged it in right out the back of my line out on my sound card (M-Audio Revolution 5.1) and the distortion went away completely. So no, absolutely do not use the headphone jack on the Z-5500's. I'm going to sell mine soon anyway as I bought some Def Tech speakers and an Onkyo receiver to replace them. Z-5500s are a great value for their quality as far a surround goes, but I don't think anyone is going to be running out and buying them for headphone use...

 

[Murmaider]

I prefer listening to my iem's and cans straight out of the soundcard. whenever i plug them into the Z's they muddy the sound quality...IMO

 

[badtrip]

Hi there..
 
What do you guys say about Z-5500 and Sennheiser HD-25 II, will z5500 drive it well?
I own a creative titanium audio card..
 
Unfortunately i have some difficulties with my computer.. i'll be connecting my future headphones via my audio card's auxillary output.
 
BTW is my cellular capable of driving this headphone? I have a HTC LEO HD2..
 
Please advice ..