Or to ask the question more correctly: Is the headphone jack a separate entity from the amp section, or does it actually draw a significant amount of power from the amp ? I've never researched the schematics of a receivers' head phone jack in relation to the main amp, so I'm not exactly sure of how or why HP jacks work the way they usually do.

Now, for the most casual situations (meaning not the greatest cans, or mainly low impedance and fairly high sensitivity ones) a standard HP jack is sufficient enough to plainly listen to an album which isn't the most detail or soundstage oriented (ie; most of todays crappy pop rock/RnB selections).

But when a discerning ear is involved in listening to some of the most lush and airy passages which a beautiful string section or symphony orchestra has to offer, more is needed out of your amp section to drive those really hard to please cans.

Examples: Sennheiser HD 650's, AKG K701's etc..

So my question to you guys is this: Is the HP jack on the 2150 a "standard fare" HP jack, or was it designed to work in conjunction with the amp to properly drive high impedance, or power hungry cans (there is a difference between high impedance and power hungry too) ?

Curiously yer's,

Doug

Headphone jacks must have separate headphone amps because they don't want to use the same level of power as regular speakers. My understanding is that they take a copy of the "pre-amp" signal before the amp and feed it to the headphone amp. How good that headphone amp is would determine how the receiver does with more difficult-to-drive cans.

I'll have to leave discussion of the chops of the 2150's headphone amp to other, better souls...

Doug,

I believe you'll have no problem driving any type of headphone with the 2150, from the HD650 to K701's . I use the easy-to-drive HD 595's, and I am very happy with my listening experience.

I asked Scott before I bought my 2150 about the performance of the headphone output and how it was driven. I believe he relayed to me it is not driven directly from the amp and reduced via resistors like some are, so it has it's own amp.... but as gonk said it 's signal is from the preamp. He assured me the headphone output was inteneded to be as good as the rest of the amp, not just a "courtesy jack" .... as I pointedly asked him if it was.

Both volume controls can be used to adjust the volume... bass and treble work, the speaker EQ is defeated.

I can't say I'm an audio perfectionist, but I have my boundaries of what is "good sound".... and it does sound good! I am very particular about background noise though, especially using heaphones ..... and the 2150's headphone output is very quiet..... I'm quite happy with it

By the sound of your post you do not have headphones ? .... and you have a 2150 ? If you're wondering how low efficiency can will sound, the only way is buy 'em to try 'em. I bought about 5 different ones before settling on the HD595's. The HD5xx series are designed to deliver the sound into your ear a bit more directly than other headphones, and to me they deliver an experience unlike any other headphone. Wow , is all I can say..... and they're very efficient to boot. I never tried the HD650's because double cords drive me nuts, so I can't give you any feedback on those.

Wether the 2150 sounds as good as a $500 stand alone can amp is highly subjective and up to the listener. Before I tried the 2150, I was thinking I'd have to get a seperate can amp because all the amps and receivers I tried had noisy headphone amp sections. With the 2150 I have no need for one. Everyone's taste is different .

Thank you for the feedback guys. Garth, it's actually the other way around. I do have several pairs of cans, but no 2150 yet. I had ordered one, but then a week later was in a car accident (everyone is ok) so had to prioritize the financial side of things. I've actually had HD 555's for a few months, as I was lent a pair from Headroom to audition and do a review with. Also had a chance to get some Grado's from them, as well as their Bithead amp.

I currently own a few IEM's, which don't need an amp to drive, but I absolutely know that when I get the 2150, I'll want some really nice cans to float away with, during those moments when speakers aren't permissible. I also have Sony V6's, but would hardly consider them to be high end cans, let alone hard to drive or even lush sounding.... They're good for portable use but....

I guess you're right though, I'd have to hear in order to tell. Though I may get a dedicated amp for comparison's sake.

sweet spot, you say you currently own a few IEM's, which don't need an amp to drive. I don't really agree - the bithead you mention does a lot to improve what I get from my IEM and I would not want to listen to mobile audio without it now. as for the quality of the headphone jack on the rr2150 - it's not as good as a dedicated headphone amp at the same price, but it's as good as the total bithead. I use a pair of AKG cans with it and am pretty happy. it's probably not for critical listening, though (I prefer the IEM or of course a good pair of speakers, maybe even plus sub!)

Melo, no offense, but how could you possibly not agree with me, without knowing exactly which IEM's I have? You can not in any way shape or form, lump all IEM's in together. Perhaps I should have said In ear Canal phones though, rather than IEM's. Usually that distinction is given by the manufacturer, rather than the average user.

For example, one pair that I own, are the Super.fi 5 pros, which for all intents and purposes is just an in ear canal phone. And IEM would more properly be claimed as one that was custom made to fit your specific ear canal, as in a custom molding. Anyway, my Super.fi's are extremely efficient, as well as well balanced without the need of an dedicated amp. I know this because I've done comparison testing. I've done this with several pair of "in ears" actually. From the super.fi's to Westone UM2's and a few of the Shure's.

The added benefit of a portable amp was pretty insignificant, and did not justify the price of one whatsoever. In many cases, I believe that a portable amp is overkill, and severely over rated. When traveling, especially by means of public transportation, I find it ridiculous that anyone would go to such great lengths as to bring a portable amp, all the cords to accompany it, and then of course, good enough cans to allow the music to shine.

And then, we've got another issue all together, don't we ? Unless you've put lossless music on your DAP, what exactly is the point of trying to make compressed music sound "good" ? I'd rather not have my great gear expose that crappy compressed music for what it is, thank you very much.

For home listening, when I'm not able to use speakers, there's really no way I'm going to stuff an IEM into my canals. I'd rather wear proper cans, which can give me the added soundstage and separation that the music I listen to, deserves. As good as some of the higher end IEM's are (UE 10's or Sensa's for example) they just simply can not compete with good open cans.

I'm seriously thinking about the newish AKG K701's for that honour. I may get to audition a pair in a short while actually, so we'll see.
Should I decide that I need an amp at that point, I'll get one.

Doug

If you want to find out more about anything to do with headphones, check out the www.head-fi.org and you will have plenty of informations at your disposal.

Hehe... been a head-fi member since back in 2003 But more than getting info about cans or headphone jacks in general, I wanted specific info on the RR2150 situation.

And whilst I believe that the jack on the 2150 is probably ok, I doubt that it's really much more than a standard jack. No offense to the company, but what else would any manufacturer say about the quality of their product, other than "it's great" and such. So while it's nice to hear Scott saying something along the lines of "it's not just a courtesy jack", I can't really help but think that there's no real proof of this, as it would be indicated in audio reviews, and would also be listed in the spec sheet as just one more "up" on the totem pole.

It doesn't bother me all that much really, since there's no surprises but, I'll take what I can get.