Seeing as the iHP has only one stereo DAC, I don't see how the EQ could possibly be bypassed.

If your player uses capacitors to couple the output (I'm pretty sure the iPod does) then you'll get a high-pass filter with low impedance headphones. In this case it may be better to go with the ER-4S, which won't roll off the bass as much. Sort of a compromise between subdued highs and bass...

Most are just going to say the best is the player they currently own. Good luck.

You'll need a test harness that can sample the voltage across your headphones if you want to do load testing. Otherwise, just put the sound files on your player, then hook it up to the line-in on your sound card. Calibrate the input/output levels and then test.

Those 1kHz intervals are the harmonics. The THD for the headphone out isn't that bad- those peaks are below -90dB. If you look at the end result, the THD is about .01%- really not that bad for portable audio. It's on par or better than the Karma at least and should be about the same as the iPod...

The FM radio needs some sort of ADC to feed its signal into the digital audio bus.

Quote: Originally posted by Traveller Thx, that's a great start Now the question is if say, this TLV0834I A/D is any good...? 8-bit... sounds scary to me...! I'm thinking that this ADC may be used for the FM radio section... Even the Motorola processor has a 12-bit ADC that could...

Better stereo image, perhaps. There's no amplifier on the line out so there's probably less crosstalk on the power rails. However, you pay the price with rolled off treble and bass (unless this is what you like) since the line out can't properly provide the current to low impedance loads. You'll...

Ah yes, I thought you were one of those crazy directional wire-impedance matching guys. Apologies.

Why would you want to match input impedance on an amplifier to the output impedance on the source? For modern amps, the goal is maximum voltage transfer; for this to happen you want a much higher input than output impdeance. For the amplifier to speakers stage, impedance matching will give...

The recent firmware (1.4) does not change the EQ behavior at the line out port as measured by RMAA (and it's very apparent when listening too.) I don't know if I quite agree with your assessment of the volume control Kelvie. The volume could be controlled by just setting the maximum voltage...

IMO, you can't say a line out is amped just because it has the same apparent sound level as the headphone jack. Also, would you not call the output from a phono pre-amp line level, even though these by necessity do some equalization of the signal? I think line out is a very loosely defined term...

Do you have evidence that the line-out is amped? When I made my measurements: http://www4.head-fi.org/forums/showt...threadid=53916 the line out had distortion under a low impedance load, which indicates to me that it is not amped. I think out of the box, the players have essentially the...

The 100kOhm load completely explains the results if both measurements are on the same jack. The headphone jack is usually coupled with a capacitor, that's what causes the bass roll-off. Any correction to this in coupled systems involves sound processing.

This is a picture of the backside of the AC adapter that came with my iHP. As usual, YMMV etc...

Fixed the stuttering problem. Just a matter of different buffer sizes for different files...

To reiterate what others have wisely said, use the shirt clip up high, and the cords should kind of hang in front of you out of the way for most motion. I use them in a lab where I move around a lot and rarely hear any microphonic effects.

The iRiver offers neutral bass with the EQ off: With the UBASS and ROCK EQ options, there is about a 15dB boost between 0-40Hz and a roll off from there to 200 Hz. The ROCK EQ adds about 3dB to the 10kHz+ band. My listening impressions: neutral sounds very good with ER-4"S"- you...

I just realized that having a frequency dependant load might be a bit confusing (the response curve plots voltage...) so I've redone a measurement with a constant 51 ohm load: 51 ohm test As you can see, it no longer looks like there is increased high frequency response (it's actually...

Hey oddball, thanks for the info regarding the tips. That is good stuff IMO! I live in a pretty sheltered area for electronics, so I haven't even seen the EX71 in stores... As far as exaggeration goes, I wasn't referring to you CrawlingEye. I think your approach was very balanced in fact.

Here's my problem with always suggesting e2c+ex71 mod. How does one obtain the sleeves from an ex71 if one does not already own said headphones? Buying e2c+ex71 can get rather pricy. It seems to me the e2c would be a good choice alone if the sound is right for the purchaser. Also, please be...

Which 1kHz bump are you refering to (which graph?) In the dynamic range and THD tests, this is the test signal that is used to calculate the reported values. As far as the bump at 2.5 kHz in the low impedance frequency response test goes, it is caused by a bump in the impedance curve for the...

Quote: Originally posted by TheMuffinMan_01 can the ihp read stuff above 320? its stats say it can't... but is that for mp3's or non vbr media? Of course the iHP can read higher than 320 kb/s - that number is just for mp3s. It can playback WAV files and act as a decent harddrive...

Quote: Originally posted by dj_digital So do those tests indicate that the ihp has theoretically better sound than the Karma? I'm not too familiar with rmaa so could someone explain these results a little? Thanks dj_digital There isn't really a huge difference between the...

Quote: Originally posted by penbat Shure E5Cs give very high volume output. much more than Etymotic Er-4Ps. Well that's great, I'd say they should work well then and you've answered your own question.