Why are headphone amps important? - Page 2

Beware of pro-audio headphone amps and outputs. They are typically used for "monitoring" which sometimes translates into rolled off highs and lows. The M-Audio Mobile Pre, for example: perfectly adequate USB interface, but the headphone output is severely rolled off. 

 

With regards to your first question regarding the need for a headphone amp, here's what I wrote on this topic:

 

http://www.head-fi.org/forum/thread/516907/either-my-ears-are-broken-or-this-is-all-just-a-joke/120#post_6993705

 

As illustration for one of the points:

 

http://www.head-fi.org/forum/thread/495707/fiio-e7-or-cmoy-bass-boost-v2-02#post_6781213

 

Jack

I'm glad to see this stated in this forum.  I've seen a number of threads where posters state that amps only give you more volume and that's bull.

 

One significant factor to remember is that when an impedance is specified for a set of speakers or headphones, that impedance is for a given frequency and not for the whole range of frequencies that the speaker/headphone will reproduce.  As the frequency goes up or down the impedance changes significantly.  Consequently, the greater the ability of the amp to provide the power to control the speaker (actually the speaker diaphragm) at all these impedances/frequencies the better the speaker/headphone will sound. 

 

One example of how important this is considered in audiophile circles is provided in the specs of an old Krell KSA100 amp.  Although this amp is only rated at 100 watts, it was designed to drive some very difficult loads and will output 10,000 watts into .2 ohms.

 

I have an old pair of Sony MDR-V6 headphones and recently purchased a Sansa Clip+.  Also, for just $20, I decided to go ahead and buy a FiiO E5.

 

The MDR-V6s sound really good when paired up with the Clip+ (FLAC recordings) but I was amazed at the difference when I added the E5.  I was so impressed with this tiny little amp that I've now ordered and IBasso D10.  I also have Shure SRH840s which the E5 drive nicely, but I noticed a huge difference with the MDR-V6s.

 

Thats my $0.02 worth.

 

 

The V6s respond really well to amplification.  Portables, or even something like a 2000.00 tube amp make immense improvements.

It's a bit like the difference between a naturally aspirated petrol engine and turbo diesel engine. Petrol engines are like not having an amp. They produce lots of power and torque on a narrow curve, usually peeking in power and torque at the higher end of the rev range. Turbo diesels are like having an amp, they're more even in their power and torque distribution. Diesels will produce the same torque from just above idle to just before the red line, and will peek and stay in its power band earlier than a petrol engine.

The comparison goes in the opposite direction after this because on average good petrol motors are a lot more fun than diesels. Ultimately what makes a pair of headphones, an amp and a good source (just like a good car) is the character of the sound. There's an X-factor where you just fall in love with it. Most amps, most headphones and sources will color and change the sound in different ways. Amps and headphones will make the biggest difference here.

On more a basic level, amplifiers take input A, increase the overall power, and send it to output B. Amps will often push certain frequency ranges higher or lower. This makes matching them to headphones important, and it's where the subjective nature of the whole thing comes in. With Grados I want to tame the highs a little, keep the mids basically the same, and increase the bass extension some, I want to tone down the stereo separation and let them bleed a little.