[NiceCans]

Quote:

Originally Posted by Audiofiler the search tool is wonderful toy indeed...many threads on this topic with great reference therein.

While I myself am a member of 'TEAM ~ Search Button', in defense of others:
it is not always a lack of use of the 'Search' function, but often more a matter of how the search was worded causing a failure to bring forth results.

back O/T . . . .
seems all headphones sound good without an amp, but many sound signicantly better with one.

 

[Audiofiler]

Quote:

Originally Posted by NiceCans While I myself am a member of 'TEAM ~ Search Button', in defense of others: it is not always a lack of use of the 'Search' function, but often more a matter of how the search was worded causing a failure to bring forth results. back O/T . . . . seems all headphones sound good without an amp, but many sound signicantly better with one.

Yeah, I was not pointing fun at or getting down on the OP, just was suggesting that the search tool is very useful for finding more info than you can even read sometimes.

You are right though the search tool is flimsey and somewhat picky about functionality.. Nicecans, your avy is rocking cute as always!!

Back OT, pending how serious one wishes to delve (some say vortex) down the headfi path, you may opt to get a better amp at first, to allow an upgrade down the road for your cans and rig..This way you can sample sound sigs from various Mfrs, and learn more about what you like in the process!
Hope this helps

 

[Chri5peed]

Quote:

Originally Posted by Bigfieroman So, to get optimal sound quality, if not using a line-out, the best option is to leave the source volume low, say 1/3 or 33%, and amplify the signal to a

If you can't amplify a line-out signal, your source(DAP) should have its volume at maximum.

Volume on these systems is achieved by putting a varying resistance in the path. This resistance could be seen as an interference. It works inversely, so min volume is got by adding the maximum resistance and max volume is got by the least resistance.
So, putting it at max volume is adding the least varying resistance/inteference.

 

[mulveling]

Quote:

Originally Posted by Bigfieroman This is where I am confused; many people are claim vastly improved sound when using an amp...this doesn't make sense. From what I can tell, most people turn the source close to or at maximum volume, and then use the amp to adjust final volume. If there is distortion in the signal, why would it not be amplified? In other words, how does an amp make a set of cans sound better, not worse? I understand the need for an amp with phones like the Pro4AATs, they are 250 ohm. But, my computer has more than enough power to drive them to a easily sufficient volume, so I am having difficulty justifying a $100 amp purchase. I don't listen to music very loud, and after my mp3 player is delivered today, I wouldn't be surprised if it had enough power to power them to a decent volume. My best guess as to why an amp would create better sound quality compared to a battery powered source is because of the increased voltage. Volume is increased by increasing the current, but amps start with higher voltage to achieve the same power. For instance, my mp3 player uses 1 AAA battery, unless it is transformed, it is only 1.5v, (rechargable is 1.2v). Most portable cmoy amps use at least 1 9v, sometimes 2. Is that why people say amps improve sound quality?

First of all, forget the misconception that the purpose of hifi headphones amps is just to go louder - it's about higher quality at comparable volumes.

Anytime you listen to headphones, you're using an amplifier to drive them. The amplifier could be the built-in amp from an ipod, a dedicated headphone amp, or sometimes people even use the output stage of their source as the amp. When you plug your headphones into a receiver or integrated sepaker amp, a numer of things could be happening:
1) the headphone jack is driven by a headphone amp stage built into the receiver; usually of exceeedingly poor quality
2) the jack is powered by the preamp stage of the receiver
3) the jack is powered by the power amp stage with resistors added to bring the level down

It is true that amplifiers cannot mitigate distortions from a source. However, amplifiers always add distortion of their own, and this is often what audiophiles seek to minimize by replacing the low quality "stock" headphone amps with a higher quality one. Note that this point is sort of debatable though - some types of distortion are considered euphonic in moderate amounts, while other kinds of distortion sound awful even in small amounts.

Anyways, the point is that amplifiers sound different because they add different types and amounts of distortion to the signal. Cheap amps (usually the kind that are built in) often add judicious quantities of the bad, non-euphonic kind of distortion. Also of importance is that an amplifier will often output increased distortion when driving a load it wasn't designed (or not properly designed) to drive. Here's where we get into the need for a powerful dedicated headphone amp - low impedance headphones need an amp with high current capabilities, else the amp will be strained (and distort more). High impedance headphones require a higher voltage swing (again, else distortion). High quality amps will typically be capable of large current and voltage swings, keeping distortion low over a wide rage of headphone impedances. The output impedance of the amp also affects distortion. High output impedance will cause distortion, but the quick fix (global negative feedback) itself is considered to cause very non-euphonic distortion. There are many design considerations to an amp that all affect the sound.

A single transistor or opamp can't come close to doing the job right, which is why high end amp design is complicated and why the cheap built-in amps sound like crap.

Sometimes you'll see people chain a higher quality amp after a lower quality amp stage, ie: using a dedicated headphone amp from the ipod headphone jack. At first such an arragnement seems counterproductive - why would you want to add the distortion from two amps into the signal chain - however it's not necessarily as bad as it seems. By feeding the ipod amp into another amp, you're presenting the ipod a different load than that of a headphone. Typically, the input impedance of an amp is very high (10,000 - 100,000 ohms, compared to 32 - 300 for headphones), which is easier to drive (meaning lower distortion) for many preamp and headamp stages. Same with people who are using their sources (ie: soundcard) to directly drive headphones. By adding a dedicated amp, they take the burden off the source's output stage so that the overall distortion goes down (or becomes more euphonic

).

 

[Audiofiler]

Quote:

Originally Posted by mulveling First of all, forget the misconception that the purpose of hifi headphones amps is just to go louder - it's about higher quality at comparable volumes. Anytime you listen to headphones, you're using an amplifier to drive them. The amplifier could be the built-in amp from an ipod, a dedicated headphone amp, or sometimes people even use the output stage of their source as the amp. When you plug your headphones into a receiver or integrated sepaker amp, a numer of things could be happening: 1) the headphone jack is driven by a headphone amp stage built into the receiver; usually of exceeedingly poor quality 2) the jack is powered by the preamp stage of the receiver 3) the jack is powered by the power amp stage with resistors added to bring the level down It is true that amplifiers cannot mitigate distortions from a source. However, amplifiers always add distortion of their own, and this is often what audiophiles seek to minimize by replacing the low quality "stock" headphone amps with a higher quality one. Note that this point is sort of debatable though - some types of distortion are considered euphonic in moderate amounts, while other kinds of distortion sound awful even in small amounts. Anyways, the point is that amplifiers sound different because they add different types and amounts of distortion to the signal. Cheap amps (usually the kind that are built in) often add judicious quantities of the bad, non-euphonic kind of distortion. Also of importance is that an amplifier will often output increased distortion when driving a load it wasn't designed (or not properly designed) to drive. Here's where we get into the need for a powerful dedicated headphone amp - low impedance headphones need an amp with high current capabilities, else the amp will be strained (and distort more). High impedance headphones require a higher voltage swing (again, else distortion). High quality amps will typically be capable of large current and voltage swings, keeping distortion low over a wide rage of headphone impedances. The output impedance of the amp also affects distortion. High output impedance will cause distortion, but the quick fix (global negative feedback) itself is considered to cause very non-euphonic distortion. There are many design considerations to an amp that all affect the sound. A single transistor or opamp can't come close to doing the job right, which is why high end amp design is complicated and why the cheap built-in amps sound like crap. Sometimes you'll see people chain a higher quality amp after a lower quality amp stage, ie: using a dedicated headphone amp from the ipod headphone jack. At first such an arragnement seems counterproductive - why would you want to add the distortion from two amps into the signal chain - however it's not necessarily as bad as it seems. By feeding the ipod amp into another amp, you're presenting the ipod a different load than that of a headphone. Typically, the input impedance of an amp is very high (10,000 - 100,000 ohms, compared to 32 - 300 for headphones), which is easier to drive (meaning lower distortion) for many preamp and headamp stages. Same with people who are using their sources (ie: soundcard) to directly drive headphones. By adding a dedicated amp, they take the burden off the source's output stage so that the overall distortion goes down (or becomes more euphonic ).

nicely put..what Mul said

 

[ilovesocks]

Quote:

Originally Posted by Audiofiler nicely put..what Mul said

Yeah, I taught him everything he knows.

 

[tomb]

Quote:

Originally Posted by Bigfieroman My computer is a laptop, but it has an excellent soundcard. My MP3 player does not have a line out, only a headphone jack. So, to get optimal sound quality, if not using a line-out, the best option is to leave the source volume low, say 1/3 or 33%, and amplify the signal to a comfortable level? I have heard that one should turn the source up to near maximum, but it sound as if this will add significant distortion to the signal...

Yep, you are correct - IMHO. Personally, I prefer 1/2 to 3/4 of the volume control, but it depends on quality of the source. You are correct to suspect that you can start clipping with the source prior to an amp if the volume is too high (assuming no line out, of course).

Turn the volume too low, and your amp may be amplifying more noise than signal. I truly believe that without a line out, it's an experimental process.

Back to the subject - rather than write you another dissertation, think of a car:

Requirement:
75 mpg Interstate speed
Two cars can satisfy that "volume":
a) a Yugo or
b) a Nissan Z.
However, there's a world of difference in the quality of that travel, and in the ability to respond to the different obstacles that come along.

Even then, some might say, "What difference? The Yugo will get you to the same destination - probably for less cost." In fact, my daughters might say the same about headphones and amplifiers - "What difference? I only need to hear the words and the tune."

As for me, I want the Nissan Z to "drive" my headphones.

 

[kramer5150]

Quote:

Originally Posted by Audiofiler nicely put..what Mul said

Yeah.. I never thought of it that way.

If I plug my headphones straight into my line out jacks it's essentially the same output level as my govibe at ~3/4 volume... IE un-listenably loud.

Is there a passive device.. that takes that line output level and makes it variable to directly feed a headphone?... AND presents the line out with optimal impedence load?

 

[slag]

Quote:

Originally Posted by kramer5150 "how can the amp improve sound?"... Well... it can be used to EQ and color the sound to taste.

So as a foobar2000 user, what can't my software EQ do that a hardware EQ can? Since my source (Indigo IO soundcard) is great, I won't get that much benefit from using an amp for low-impedance headphones (HD595's), will I?

 

[Luckyleo]

As long as we're talking about amps, I have a question related to the line out on my Ipod G5. It definetly sounds much better than using the standard headphone jack. However, instead of the battery lasting 12 - 15 hours it lasts only 5-6 hours. Is this normal? Do you know why?

 

[tomb]

Quote:

Originally Posted by kramer5150 ... snip ... Is there a passive device.. that takes that line output level and makes it variable to directly feed a headphone?... AND presents the line out with optimal impedence load?

A pot is regarded as a passive device. Further, it's on the input side of the amp.

 

[Bigfieroman]

Thank you gentlemen for the informed and lucid posts, it is great to see how mature most of this community is. Allow me to reply in turn...

To the people who told me to use the search function; it is obvious that I know how to use the search. I was quite successful in selecting 2 pair of headphones and recognizing a need for an amp by using the search function. I apologize if my creating this thread offended you, I assumed that such a question hadn't been asked since it was rather technical in nature, but I was wrong. I do want to say that this mistake gives you NO RIGHT to be condescending to me in your replies, and I think it is ridiculous that THREE individuals felt it necessary to admonish me for not searching. Nicecans is the exception, he was polite, despite being the 3rd poster... I am new to the forum, most forums I have been to try to foster new members, not jump all over them/talk down to them for a mistake.

Anyways, back on topic. I will definitely be getting a headphone amp, as the MP3 player is getting its butt kicked by the KSC-75s, distorting like crazy and killing the battery in no time. I would also like the option to use the Pro4AATs with something other than my computer, so I think an amp is in my near future. Hopefully then I can stop buying expensive equipment...uhh, yeah...

 

[sidewinder]

I sometimes get irritated by people asking the question "what is the best" or "will this work" bla bla over and over again. Your question on the other hand is nice to read because of the great info it can provide (especially for 'newbies'). It hasn't been asked in a long time.

 

[tungsten_95]

Some very interesting posts in this thread. I normally take things I read in hifi-boards with a grain of salt, but my DT990 sounds so horrible out of my H/K AVR in comparison to my (very) old Marantz receiver that I'll soon give a headphone amp a try. The AVR amplifies without a problem, but it sounds incredibly undynamic and flat. The Marantz on the other hand sounds great to my ears. I'm eager to see what an dedicated headphone amp can do.

One strange thing: My wimpy DAP doesn't seem to have a problem with the Beyer (250Ohm). Much better sound than the CD or AVR headphone jack.

 

[aaron-xp]

Make this sticky or something. We really need a guide about what amplifiers are for, especially for newbies like me...

The search function is rather bad for this, given that we get fragmented pieces of information, so anyone willing to do "community service" for head-fi by compiling information?