[milkpowder]

Quote:

Originally Posted by jdimitri /img/forum/go_quote.gif Yes, i think the main improvement is the hiss I think an amp improves an IEM's sound a bit, but i don't think it's enough to make me carry one around (even when my amp is a supermini)

I tend to agree with you. The actual improvement in sound is subtle, although definitely present. The use of an amp is particularly useful for iPod users because the sound from the line-out is noticeably cleaner than the one from the headphone jack. However, I have abandoned the idea of carrying an amp around with me because the noticeable, but minor improvement in sound (due to the use of line-out and amp) is not worth the extra bulk, let alone the price of one of the nicer amps. I'm also not too sure whether it's the line-out that's making most of the difference or the amp...

Maybe when I get a smaller source (eg flash-based players), then I'll think about portable amps again.

 

[Desk Monkey]

thanks guys, this really helped

 

[noblsheep]

Quote:

Originally Posted by mADmAN /img/forum/go_quote.gif the plan was to have the source from a Sony Ericsson W810i (yeah yeah..i know) going through an LDM+ (high gain version) with undecided IEMs.

please don't put IEMs with a high gain version of LDM+. it hisses like a clockwork pissed-off cat.

edit: oh. adaptors.

 

[randalg]

Quote:

Originally Posted by chris in mo /img/forum/go_quote.gif Are you hooking the headphone out of your Ipod to the Input of the amp or using a line out connection from the Ipod dock connector? I was under the impression that using the doc connector and line out to bypass the internal Ipod amp and headphone jack would make a noticable improvement in the sound quality. Have you not found this to be the case?

I'm a total newb and was going to ask about this.While looking around different sites I noticed different rigs using the headphone out and others using the dock connector.Can someone tell me the differences in these two connections.
TIA,
Randal

 

[GlendaleViper]

Specifically with the Vibe, I really did not notice any quantifiable difference in sound quality at all. However, using the lineout function of an iPod and amped with an M Hornet, the hiss from the iPod's stock headphone out, which is quite noticeable, disappeared completely. I personally use the Vibe unamped simply because the phone/iPod combo is so lightweight and portable, the hiss is bearable as a trade-off.

Cirkustanz, I'm going to shamelessly plug my Vibe impressions here.

 

[kramer5150]

I have to agree on the amp hiss issues with IEMs. Depending on which MP3 player you have that hiss can be downright annoying.

For IEMS, amps add current reserves for the big bass notes. It gives the sound a more tight and defined sound.

It is my oppinion/speculation (I have no factual data to back this up) that amps typically have a higher damping factor than most portable player headphone outputs. Damping factor is (basically) the circuits ability to damp the AC backwave thats produced by the oscillating driver voice coil, once the fundamnental note stops. Damping factor translates into "how well the amp controls driver oscillation". So... an amp that is better at damping that AC back-wave will be better at controlling driver cone motion. So, in a nutshell, amps seem to control diaphragm oscillation better than an unamped circuit. Whether its a function of the circuit damping or not.... I can't really say.

Personally I use my amps to EQ and color the sound. Different OP amp chips have different sonic characters and can IMHO dramatically change how the amp/IEM sounds. FWIW I find OP amp rolling MUCH more dramatic on IEMS, because they are very sensitive and (generally) reveal a high level of detail.

 

[nightfire]

I dunno if it's been mentioned, but IEMs can benefit from an amp because often battery powered sources can't exceed a certain output voltage. This can lead to clipping (especially on IEMs with a high impedance like the ER4s) on the transients, where a sharp note (snare/cymbal hit) needs a voltage swing at the current listening level that the source can't produce.

ie. a 5 volt USB device (or ipod?) can't make a transient exceeding 5 volts (unless it uses an exotic circuit like a charge pump, SMPS, etc) - so if a very short, but loud event happens, the waveform will be clipped. It should be 6 volts, but is only 5 volts... meaning distortion.