phones directly out of CD player's RCA outputs

[Don Quichotte]

Hi guys! I am new around - well, I've been reading your posts for a year now cause I have headphonitis too, you know... Very educative, Head-Fi is great! Thanks!
Now, my question is: why aren't you connecting your headphones to the RCA outputs of your player? It is only one member around, namely Jazz, who mentioned he does this, and he reported results on a par with his EMP and Corda HA 2 amps, just a bit less appealing or something like that (I don't understand, in which way precisely less appealing?) - see his recent HA - 2 review. If you have a variable output you can use a simple, short piece of interconnect and the appropriate terminations. I don't know about impedance matching, though, maybe you could clear this up to me. I am using this improvised adapter between my CD player and my AKG K501, and it is only on very quiet symphonic passages that I need a louder sound. I guess it would work even better on CD player with higher output voltage than my 2 V. On the Sennheiser HD600 the sound is much too loud, I needed to decrease it to about -10 db. The sound is much better than from the CD player's headphone output, I found it to be even better (more sharply detailed and more dinamic, although less relaxed) than out of the headphone output of a big Marantz integrated amp (PM 17, I think). Shorter signal path, and you could spend the money on a better source. I must admit, I have never listened to a dedicated headphone amp. What do you think? Enlighten me!

 

[morsel]

Bad idea. The RCA outputs of your CD player are line level signals. The output circuits are not intended to drive transducers such as headphones, nor are they likely to have the "oomph" to do so. That's what headphone amps are for.

 

[Don Quichotte]

So I thought. But then, why didn't the Marantz amp's headphone output (supposedly not as good as a dedicated headphone amp, but many say that Marantz integrated amps have a quite good headphone jack) outperform the RCAs of the CD player? And why didn't find Jazz his headphone amps sounding much better? Jazz!! Help me get it!

 

[joelongwood]

Here's Jazz's comments from a previous post:
Quote:

Beside my headamps I use my headphones by connecting them directly to the DAC line-out RCA jacks ? via a 500 ohm potentiometer. It sounds very accurate and clean, maybe a bit dry, but it's the original signal which otherwise is half-way accurately amplified by the headamps and thus in no way fully authentic. If you like to experience the truth, then try this!

Somehow, I don't think you are doing the same thing he did, as you don't mention DAC outputs or potentiometers.

 

[Don Quichotte]

Joelongwood, I am not using an external DAC, but I don't think there should be a difference between the RCA outputs of an external DCA and those of the internal DAC of the CD player. Regarding the potentiometer, indeed I don't use one, this might be the only difference. I don't know if the presence of a potentiometer could improve the sound in any way as my experience so far suggests rather the contrary. Maybe it could help with impedance matching, but I guess most guys here should know better. If Jazz is right and you get this way a sound comparable (in quality) with that of a headphone amp then many headphone amp purchases could be a worse ideea than spending the same money on a better source, at least in the case of those who are buying their source at the same time as their headphone amp.

 

[morsel]

Maybe the Marantz you have has a weak headphone output. Maybe your headphones aren't great. All I can do is guess. My advice is to forget about connecting to the line out and get a headphone amp.

 

[Don Quichotte]

Thanks for your replies. I don't want to annoy anybody insisting on a question that might seem stupid for most of you, but have you LISTENED to such a setup, or are you just making a logical deduction? If your belief is based on your ears, than I would really appreciate if you could go a bit into details: lows are uncontrolled, soundstage is collapsed, the whole sound is compressed, etc. and how big is the difference. By the way, my current phones are K501, really really demanding from what I've read.
Thanks!

 

[Don Quichotte]

NOBODY tried??!

 

[JaZZ]

Don...

You may already know my opinion on this subject. And your own experience gives you the right image: the direct path (DAC [RCA] line out as headphone amp) is faster, clearer, more focussed, more precise, more dynamic – and less colored as well as less colorful

– than any amp. Even though you have chosen the most unfavorable circumstance, in the form of the low-sensitive K 501, you notice better sound compared to the dedicated headphone amps (-outputs) you have at the disposal.

There seems to be a common bias: a line-out amp isn't able to drive a headphone adequately. Those who try it will change their mind: there is no shortcoming with this array, except for a potential loudness level restriction in the case of low-sensitivity headphones. But there's one precondition necessary: a low output impedance. Anything below 60 ohm is unproblematic. You'll notice that there's no distortion at all, no clipping, even at the highest levels possible, and if, it's the headphone which is the cause. And there's also no lack of bass (impact or level) at all. Nor is any rounding of treble.

The ideal case seems to be a variable line output – if it's of high quality (not self-evident!). Otherwise a (500 ohm) potentiometer serves well and without great loss of balance neutrality (possibly a slight increase of bass). Effectively there will never be 500 ohm serial resistance (see the «Impeder»), but some in the range between –0 (min. and max.) and around 120 ohm. This is a value which is normal for common tube amps BTW.

So, from a puristic point of view, there's nothing better than to renounce a superfluous amplification stage, even though the line out amp originally isn't designed for this purpose (morsel). But you can use a pre-amp output as a headphone amp and vice versa. Actually its only difference to the line-out amp is its higher level – and the buffered potentiometer, to compare it with the direct path solution. But if you don't need the higher gain, you can renounce it.

In reality it's not so clear. Well, with my speaker rig I renounce the preamp; this has a very similar effect as to renounce the headphone amp. But in the case of the speakers I managed to fine-tune the crossover networks to make the system sound great anyway. This is not possible with headphones. You have to take what you got, more or less. My experience is that especially with digital sources it's very, very difficult and delicate to get the right tuning the less electronic are in the signal path, thus the more true and accurate the signal is. Speaking of headphones, you must imagine that you have quasi the unfiltered DAC sound in your ears. And this is by all means a technical sound, additionally restricted by the («data compressing») digital format. Every amp seems to transfigure this original sound into a more forgiving one – be it tube- or solid-state based.

It's primarily kind of too high resolution with the direct path: I'm pretty sure you definitely hear the digital electronics or the digital format's shortcomings. The sound is a bit coolish, I would call it digital, but on the other hand it shows finer and more subtle details and greater speed and dynamic than through any amp. And it seems to be too transparent – the soundscape is downright a bit empty... But that's in fact an overdrawn description. The direct path will sound better with most sources except for some very good headphone amps (actually: very good sounding...): they fill the emptiness by broadening and accentuating the details (solid state) or by rounding them and increasing color contrasts (tubes) and create a more coherent and colorful entity. A characteristical detail: the only one of my headphones which clearly sounds best with the direct path is my Etymotic ER-4X – modified and fine-tuned to my liking.

JaZZ

 

[morsel]

Sigh.

Of course I have tried it, and I stand by my previous statements. There may be a few line out stages that are capable of driving headphones directly, but they were not designed to do that. A good headphone amp will be a superior solution regardless of headphone impedance. I completely disagree with Jazz. The notion that line outs are generally superior to headphone amps is ridiculous. If Jazz was correct, no one would use headphone amps.

If your Marantz headphone jack sounds worse than your CD player line out it is because your Marantz sucks or is defective. Your Marantz does not equate to a headphone amp.

I am done here, believe what you will.

 

[Don Quichotte]

Thanks a lot, Jazz, I really appreciate your detailed answer! Indeed, you have described quite accurately my experience with using an amp (I repeat, not a headphone amp, but several good amps; besides the drawback in detail, transparency, extreme frequencies handling and many other attributes, even a crappy headphone output of a CD player gives you a little bit of the advantage I heard with amps over the direct path). I'm talking about an obviously more relaxed and somehow more coherent, more detached and more colorful sound when using an amp. I see I almost used your words: "create a more coherent and colorful entity". On the other hand, the most striking advantages of the direct path as you call it were for my ears a better (more extended, more impactful, more defined) reproduction of the extreme bass and highs and greater speed and detail over the entire frequency spectrum. Couldn't you simply compensate for the cold and analitical approach by buying a better, more analog-like sounding CD player, maybe a tube equipped one? I would be EXTREMELY curious to compare money-equivalent setups like (just writting randomly some serious brands) Arcam CD player + EMP + HD600 against Cary CD player + HD600 out of RCA outputs... I have no ideea which would be the result, but I'm so curious!
Thanks again!

 

[Orpheus]

i've talked to Monarchy's president/engineer before: Mr. Poon. i was originally buying his sm-70 pro for my k1000's.... but he told me his DACs are able to drive normal headphones fine just from their RCA outputs, and in fact many of his customer have done just that ...i think all his DACs have a potentionmeter, so you can adjust the volume if you want.

i think that there are many issues concerning the best in headphone amplification.... but it can't hurt to try connecting them to the RCA's.... at least on Monarchy's line level equipment.

try it and let us know what you think.

 

[Nefarion]

Decent headphone amps set up right will always blow away the direct rca line outs in cd player. Compare them and it will become quite obvious. I did quite a bit of no headphone amp listening out of rca's... When i finally recieved some decent amps the difference was night and day... Of course I was using HD600's most of the time.. But i also used some sennheiser hd490's and koss porta pros. I think its an obvious fact that running headphones directly out of line outs will not equal near the same quality sound reproduction compared to running out of dedicated amps. As previously stated, the outputs for line outs are not tuned for optimal headphone listening... Will it be adequite using some headphones for some people? Yes.. Will it be considered an "audiophile" level of quality?... it would be a stretch to say so. Of course it depends on the souce in the cans.. But any decent amp will blow away what the same source can do without an amp.

 

[JaZZ]

morsel...

...instead of your sullen good-bye I would have liked better to know some details about your experiences with the direct path, which you possibly would have taken more seriously («Of course I have tried it») without your obvious bias:
Quote:

...they were not designed to do that.

You mean like «Humans aren't born to fly.»

Anyway, a quite unsubstantial argument...


Nefarion...
Quote:

...any decent amp will blow away what the same source can do without an amp.

That's more or less what I experience myself. You just have to question this «blowing away» a bit: I think it's an unexpressed common sense that the more attractive or more beautiful sound is the one which is more true. This can even blow all logical thinking away and replace it by some reasonably sounding platitudes («...not designed to...»). I think I have done all necessary care to prove that the direct sound simply is more true. (See my corresponding postings.)


Don...

...I just want to say how much I appreciate your highly sensitive HD 600/K 501 comparison... well, I'm a bit late.

I guess some tube-equipped DACs possibly could compensate for the analytical coolness of the direct path (pity I have none at the disposal), but it may even not depend on tubes ore solid-state. My brand new Philips DVD 963SA's RCA output is very, very good for direct path purposes. Its by nature warm and rich sound doesn't suffer that much from any lack of euphonic coloration. Nevertheless it's still topped by the Corda HA-2 in terms of impressivity and colorfulness, but it's close.

Anyway, I think the subtle colorations (in the best case) an amplifier stage adds to the sound will always sound more attractive than the sonic truth (see Aphex Exciter & Co.), and I'm rather sure that the sonic superiority of the analog disc which some people still perceive is well to a certain degree due to its higher resolution, but to an even greater degree to some euphonic colorations arising during the transducing process (the hypnotizing sound of a diamond needle floating through an oscillating canal in wonderfully elastic vinyl). No chance for the plain truth!

JaZZ

 

[Nefarion]

"I think I have done all necessary care to prove that the direct sound simply is more true"

So what is true? Obviously the bottom line, the truth is the intrument (vocal cord, string, whatever) making the sound.. So your saying the direct out of an rca ... at any time with any setup.. will sound closer to the actual sound than than it would with a dedicated headphone amp. I see your logic... Less clutter = purity. But i think the flaw in that logic lies in the in fact that the souce output is developed with the intention that it will be amplified... Your logic is that the source is the cleanest, least edited signal. But the fact is it is still edited... and it is someone elses idea of how the reproduction of your music should sound. The ideal amp which amp makers strive for is one in which "edits" the source into something better. So to say the source will have the most true sound isnt a fair statement to me because the sound of the source itself is not true until it is used in the way it was designed and developed to be used. Who really knows what true is?? The people who have heard the actual instrument... But of course thats not feasable.. So we must make our best judgement as to what true is to us. The truth in sound reproduction is an opinion... And in my opinion, the sound from rca jacks source that ive tried is always inferior to the sound from the headamp hooked up to the same rca from the same source. Ive only tried it on 3 different dvd players, so maybe i havent done enough comparisons.. I really need to try it on something high end... But its pretty obvious to me what my findings would be. Night and Day like all the rest of the soruces ive tried.