[Davesrose]

Quote:

Originally Posted by cribeiro /img/forum/go_quote.gif Nice try..., but no, sorry. Don't worry!! You can anyway enjoy your great gear while I envy you nastily Probably because you have better ears, also. Hey, that is not fair!! I have just realized you have corrected your post while I was writing... And you are right in part (even a bit more, after your editing).

Well at least I was close

At least it's good to know that nothing in the real world is absolutes: which makes sense because there are so many variables that effect something. For example, a soundwave (btw, I did mean density....but density smensity: I remember from high school science that it's proportional to volume

). Does quantum mechanics study how soundwaves might be dispursed through the various states of air?

Well at least I've learned that ways of quantifying angular speed and velocity are different for each specialty. And that this stuff is really complex after I've gotten back from dinner and have two pints of beer in me!

BTW, while my physics knowledge is at high school level....I think I do have a pretty good ear for music and audio reproduction: 22 years of playing an instrument and attending concerts. My audio setup is pretty good if I do say so myself.....if you're ever in ATL, you're welcome to have a listen: SACDs, CDs, and now vinyl are all sounding pretty good

 

[cribeiro]

Quote:

Originally Posted by n2xe /img/forum/go_quote.gif It's not dependant on frequency, line length or prop velocity per se.

Are you really sure about this? Or is it for your particular application?

 

[Davesrose]

Quote:

Originally Posted by n2xe /img/forum/go_quote.gif I think I can see why the CX-300 gets a lot of mixed reviews. Some people love them and some say it's too bassy. I don't find it to be too bassy and after looking at the FRG you folks provided I was really wondering why. Since the SR-325i has 32 ohm impedance, the difference is not as pronounced.

Yep, source and output of amp plays a role in how a headphone sounds. Every headphone also sounds different because headphone companies have specially designed their diaphragms to be weighted in certain areas of the sound spectrum. If you use the same source with the SR325i and HD650, they'll sound completely different. Not just because of the different load requirements (SR325i being 32 ohm at around 100 db/mv while the HD650 is 300 ohm at 97 db/mv), but because of the design of the headphone. The 650 was designed to sound like a concert headphone. It's popular for classical music because Sennheiser designed the bass to be more pronounced, the mids to be softer, and treble to extend (exactly the way accoustics are in an auditorium). Grados are popular amung rock musicians, because their upper mids are more pronounced. I like the 325i for when I'm listening to a horribly compressed rock CD. The extra brightness is needed when a CD is "hot" (sound engineers will bring up the loudness so that the music isn't as dynamic). The HD650 may be too "laid back" under a compressed source or if it's underpowered.

I think another reason why headphone reviews are so subjective is because of the listener's preferences as well. I've noticed my impressions of headphones can be different then some people who only listen to rock (I like rock, electronica, jazz, and classical).

Gotta scoot again.

 

[cribeiro]

Quote:

Originally Posted by Davesrose /img/forum/go_quote.gif Well at least I was close At least it's good to know that nothing in the real world is absolutes: which makes sense because there are so many variables that effect something. For example, a soundwave (btw, I did mean density....but density smensity: I remember from high school science that it's proportional to volume ). Does quantum mechanics study how soundwaves might be dispursed through the various states of air? Well at least I've learned that ways of quantifying angular speed and velocity are different for each specialty. And that this stuff is really complex after I've gotten back from dinner and have two pints of beer in me! BTW, while my physics knowledge is at high school level....I think I do have a pretty good ear for music and audio reproduction: 22 years of playing an instrument and attending concerts. My audio setup is pretty good if I do say so myself.....if you're ever in ATL, you're welcome to have a listen: SACDs, CDs, and now vinyl are all sounding pretty good

I hope you enjoyed your meal

About Quantum Mechanics and sound waves... I imagine it can be done, but I have never seen anything about it, and I do not know if it would be practical, since the sound waves are macroscopic.

And as much as I envy you for your ear, audio setup and playing skills, i would not trade any of my beloved equations for them

(this is well-meant, of course) But I keep hoping I might learn to play the guitar, and I will definately save up enough for a nice gear. But I very welcome your offer to listen to your setup! Thank you very much.

 

[bellsprout]

Quote:

Originally Posted by n2xe /img/forum/go_quote.gif The frequency of a sine wave is its angular velocity.

wrong... i don't know how many times it's been explained and how many more times we need to explain it to u. the concept isn't that hard to grasp...

Quote:

Originally Posted by n2xe /img/forum/go_quote.gif The rate of change of angular displacement is zero because there is no variation in the angular displacement over time.

wrong...the average angular displacement over a long time is zero. rate of change (first derivative) of angular displacement is anything but that. if the rate of change of something is zero, it's not moving.

Quote:

Originally Posted by n2xe /img/forum/go_quote.gif This is exactly what I've been saying all along and even the physicist agreed that in the special case I described, I am correct (again).

plz get off ur high horse and just read and reread a few of our previous posts. we're not trying to "beat" u - if we wanted to do that we'd have given up a long time ago. there's a wealth of knowledge here and there's a lot u can learn. but if u want to wallow in ur ignorance and try to put us down, that's fine too.

ps i didn't spend $653 on snake oil. i spent it on headphone, iem, dap and parts for a portable amp i'm making

pps i can't believe u thought my frequency response graph was anything but photoshopped. there's a difference between real frequency responses and ones that are physically impossible. think about it for a bit u can easily see.

 

[cribeiro]

Quote:

Originally Posted by bellsprout /img/forum/go_quote.gif wrong... i don't know how many times it's been explained and how many more times we need to explain it to u. the concept isn't that hard to grasp... wrong...the average angular displacement over a long time is zero. rate of change (first derivative) of angular displacement is anything but that. if the rate of change of something is zero, it's not moving. plz get off ur high horse and just read and reread a few of our previous posts. we're not trying to "beat" u - if we wanted to do that we'd have given up a long time ago. there's a wealth of knowledge here and there's a lot u can learn. but if u want to wallow in ur ignorance and try to put us down, that's fine too. ps i didn't spend $653 on snake oil. i spent it on headphone, iem, dap and parts for a portable amp i'm making pps i can't believe u thought my frequency response graph was anything but photoshopped. there's a difference between real frequency responses and ones that are physically impossible. think about it for a bit u can easily see.

Have you seen his last post? Let's calm down we both, he is starting to see sense... Or not?

 

[tbritton]

Quote:

Originally Posted by n2xe /img/forum/go_quote.gif I think I can see why the CX-300 gets a lot of mixed reviews. Some people love them and some say it's too bassy. I don't find it to be too bassy and after looking at the FRG you folks provided I was really wondering why. Again, we were debating my assessment of several headphones but keep in mind, that's with an iPod as the source. I usually listen to the CX-300 with my 4th Gen 20GB iPod and that makes a huge difference. 4th Gen iPod use a class A output amp with capacitors to remove the DC bias. I measured the output impedance vs frequency on that iPod this afternoon. Because of the output capacitors, the output of the iPod starts climbing above 5 ohms at 800 Hz to about 45 ohms at 20 Hz. All things being equal with 16 ohm CX-300, you get a 9dB drop in signal at 20 Hz (about -3dB at 100 Hz). Those of you listening to CX-300s with a source that has a direct coupled push-pull driver are going to get a lot more bass than you will with a 4th Gen iPod. Just for kicks, I plugged into my iPod Shuffle (direct coupled, push-pull output) and there is a significant difference. Since the SR-325i has 32 ohm impedance, the difference is not as pronounced.

Now we're talking like a true member of head-fi!!! Glad to see you "in the groove" again, n2xe. BTW - many IEMs are low impedance and suffer from this bass roll-off when using the iPod lines.

Your knowledge and insights would be a welcome addition to many other threads here, so please do browse the site some and contribute some more.

And here's something you might enjoy put together by a sound-reinforcement person like I used to be. Thanks goes to Contrastique for submitting this link (particularly she submitted it for the pink-noise track, but it is a very interesting compilation of test audio you might all enjoy.)
http://www.binkster.net/extras.shtml#cd

Terry

 

[n2xe]

Quote:

Originally Posted by cribeiro /img/forum/go_quote.gif Are you really sure about this? Or is it for your particular application?

Yes, I'm sure. A reflection will occur regardless of line length (or propagation delay, which ever you prefer). If the line length is short compared to the wavelength (of interest) then the effects may be so small that it doesn't matter.

Particularly with audio since the highest frequency of interest is 20 kHz so one wavelength is 500,000 feet. A 100 foot run to a speaker is 1/5000 (more like 1/2500 in wire since the speed of propagation is about 1/2 C) of the wavelength so it hardly matters or is noticable, or measurable for that matter.

This actually is my area of expertise (I know, hard to believe), I have a patent (USPN 5,136,187) on a temperature compensated terminator that I developed for an application where it mattered (I don't think it ever saw the light of day however).

 

[n2xe]

Quote:

Originally Posted by bellsprout /img/forum/go_quote.gif wrong...the average angular displacement over a long time is zero. rate of change (first derivative) of angular displacement is anything but that. if the rate of change of something is zero, it's not moving. plz get off ur high horse and just read and reread a few of our previous posts. we're not trying to "beat" u - if we wanted to do that we'd have given up a long time ago. there's a wealth of knowledge here and there's a lot u can learn. but if u want to wallow in ur ignorance and try to put us down, that's fine too.

Is not 100 Hz 628.3185 radians per second? Is not the angular displacement always 628.3185 radians per second? For an unmodulated, pure sine wave isn't the change in angular displacement always zero?

I can learn a lot here. Likewise so can you. All I ever asked was for a fact based debate. About 10 pages were pure name calling. When facts were presented, I evaluated them. If they made good sense, I accepted them. What more do you want from me?

 

[n2xe]

Quote:

Originally Posted by tbritton /img/forum/go_quote.gif Now we're talking like a true member of head-fi!!! Glad to see you "in the groove" again, n2xe. BTW - many IEMs are low impedance and suffer from this bass roll-off when using the iPod lines. Your knowledge and insights would be a welcome addition to many other threads here, so please do browse the site some and contribute some more. And here's something you might enjoy put together by a sound-reinforcement person like I used to be. Thanks goes to Contrastique for submitting this link (particularly she submitted it for the pink-noise track, but it is a very interesting compilation of test audio you might all enjoy.) http://www.binkster.net/extras.shtml#cd Terry

I wish you posted that a day ago. I spent a couple of hours recording test tones with my trusty old Hewlett-Packard 200CD Audio Oscillator...

 

[tbritton]

Quote:

Originally Posted by n2xe /img/forum/go_quote.gif I wish you posted that a day ago. I spent a couple of hours recording test tones with my trusty old Hewlett-Packard 200CD Audio Oscillator...

Heh - I hope it saves you some future work, then!

Terry

 

[tbritton]

Here is a link to some discussion at Hydrogenaudio concerning the low-impedance bass roll-off issue (which itself has links to further discussions and graphs of test results.)

http://www.hydrogenaudio.org/forums/...howtopic=51344

I wound up over there doing some reality-checking of research I'd done concerning a gain-staging question of how to overcome the iPod's Equalizer, with its built-in settings and no preamp adjustment, exhibiting distortion problems. The major fruit of my labors is at the post below, but read that whole thread if you want some history and deeper considerations. As it turns out, many mp3's and aac compressed files possess internal clipping problems which can be overcome by the mp3gain and aacgain programs.

http://www.head-fi.org/forums/showpo...6&postcount=77

Enjoy!

Terry