[Currawong]

It's hard to imagine what something is like if you haven't experienced it. From time to time someone will set up a cheap rig and insist that spending anything more than they have is crazy and all amps or DACs sound the same, despite people with more experience knowing better. Boomana wrote up an excellent post, in reply to a discussion on amping headphones, the difference between getting sufficient volume and sufficient amping:

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Originally Posted by boomana /img/forum/go_quote.gif I don't know anything about ripple, but I'm confused reading your response to tomb because you seem to be talking about different things. You're talking about loudness, and tomb isn't. Unless I'm misinterpreting your words, you're saying that certain soundcards can drive known difficult-to-drive headphones to sufficient volumes. As far as I know, that point was never in question. I'm not a technical person, so I'll just give an example from my listening experience, so forgive if I'm missing either your or tomb's points, but here's my understanding: Let's take one of the most notorious hard-to-drive headphones, the K430s. I was certainly able to get sound from my computer soundcard, but not sufficient volume (no, I don't have one of the newer, reportedly more powerful soundcards, and I admittedly know nothing about them), and the sound was thin, flat, and disappointing. I could plug my headphones into the micro amp I had at the time, or even the jack of the Eastern Electric MiniMax cdp I had with better results, but not really. The music was louder, but really unsatisfying, though I could certainly get a taste of the K340s sound signature and the beautiful mids. I bought a Heed Canamp and a Darkvoice 336, which were $400 and $260 at the time (I have no idea what they are now), and what a difference! Not only was I able to get it way past volumes I would want, the sound quality drastically improved at normal, safe listening volumes, and I was suddenly noticing parts in the music (mostly in treble and bass) that I hadn't noticed before. I became aware of imaging, and a sense of where the instruments were placed in relationship to each other, an idea of "soundstage" and depth, etc. that were not present with other, less powerful amps. I had to turn both amps up to a certain volume (a wee bit loud, but not too loud) to hear the music like that, but it was wonderful when I did. I suddenly knew the benefit of more powerful amps with certain headphones. Jump forward about a year, and I got a SP Extreme Platinum, which I'd bought to drive K1000s single-ended since I didn't have a power amp at the time, and having heard the amp at a meet, I knew it could drive all my headphones. I thought it might be a Swiss Army knife of amps, and it still is my only full-size dynamic amp. Anyway, I plug my K340s into it, and the bass is cleaner, tighter, and with a better sense of attack and decay. That jumped right out at me, but here's the kicker: I could turn the volume down to almost inaudible levels, and every bit of music was presented as fully as it had been with the Canamp and DV, but with those, I needed to have the volume borderline loud to hear it the same. And with the SP, at the same "normal" listening level as with the Heed and DV, the K340s had a more open sound, with much better separation of notes (e.g., can hear individual notes in tympani rolls, not just the roll) and sense of balance from bass to treble (heavier mid emphasis with the DV and Heed). That experience was the first to teach me that driving a headphone "well" had very little to do with volume. Volume was just one factor, and since that time, it's never been a deciding factor for me when choosing an amp, since most amps can produce adequate volume. BTW, I ended up using the SP as a preamp to a FirstWatt F1 for the K1000s, and the best I ever heard the K340s was with jp11801's re-terminated to a 4-pin pair, using a K1000 tail and the FirstWatt. Holy moly! These headphones are seriously underrated because they are usually seriously underpowered. Can a decent desktop (DV, Heed) drive them enjoyably? Absolutely! Can it drive them well? That's debatable, but in my opinion the answer is no. Oh...and the SP could definitely drive the K1000s to sufficient volume, but also not drive them well. The K1000s definitely need a power amp to bring out their sound. Now, I just used those headphones as an easy example, but I've found the same to be true with the HD650s, K701s, and though I sold my HD800s, the limited experience I had with those headphones is pretty much the same. I don't know of anyone who would tell someone not to enjoy their headphones, if they do, from whatever they're using to drive them. Enjoy! On the other hand, it's also alright to acknowledge that sufficient volume doesn't always equate with being well-driven.

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Originally Posted by boomana /img/forum/go_quote.gif I just want to add that the whole my headphone is loud so it's being driven well argument is in the same category of misinformation of tube amps are warm and lush, and solid state amps are analytical on this board. Just because it's sometimes true doesn't not mean it's The Truth, and in reality, examples proving the opposite are probably more plentiful. 1) If your headphones aren't capable of revealing differences, you won't hear them. Different headphones have different requirements. 2) If you've never had the opportunity to hear a specific headphone with wide variety of amps and sources, not just one or two, you might not believe there are differences, even they exist; and just because a certain headphone doesn't reveal changes in amps or sources (there are many that don't), doesn't mean others won't. 3) Critical listening is a skill that must be learned and honed over time. Back in the late 80s and early 90s I lived with a well-respected record producer, mostly jazz, who even won a Grammy. Being an obsessive nut over every little everything, when working on a project it was 24/7 in the studio and then at home, actually bringing the R2Rs with him when in the mixing and mastering phase. He'd listen on both speakers and headphones around the house, and would sometimes ask me my opinion, saying, "What do you think of this (some ever so subtle change he did with something)?" I couldn't hear what the heck he was talking about until he taught me how to listen, and the truth is that it annoyed me to learn to listen critically. It took effort and concentration and I found it very frustrating at first, but over time (a couple years, not weeks), I learned to hear and distinguish things quickly and clearly that I absolutely couldn't hear before, and even then I couldn't hear what both he and his sound engineer could hear very well. I don't listen critically 95% of the time now because I don't like to, and I'm pretty aware that I've lost some of the skill I had back then. You can't describe subtle differences in certain colors to someone who is colorblind. It doesn't mean others can't see them, and that they don't exist. Same thing here. I think so many of the disagreements on this board come folks battling over issues with roots in those three areas. At some point you just give up trying to say anything at all.

 

[carickw]

I've read a couple of the earlier blogs and am a relative novice. A different blog said to buy multiple headphones and then demo them and decide which is your favorite and them match equipment to them, so i recently bought HD650s and Grado RS-2is, and awaiting delivery. After reading this, it makes me question how effective a demo without the proper equipment is. Say the HD650s need a proper amp to sound good and the Grado's improvement with an amp is minimal (totally hypothetical), obviously the Grado's would sound better in my demo, but I don't know how they will compare to a proper set up. I guess I am just a little confused over these two blogs.

 

[Currawong]

carickw: I sympathise, as I had a pair of AKG K701s which I sold before I ever got to use them with any kind of rig that might have brought out their potential.

IMO, you'll probably get a fair idea of what both headphones are like, if not their potential. Some of the effect of amping will involve a change in tonality. For example, you'll probably get more bass from a better amp in most headphones, which can make the music more fun to listen to. Cheaper tube amps often have a softer treble which can mask harshness and is more pleasant to some people. From an audiophile perspective, from better amping you get more detail and and the music sounds like it was recorded in a larger venue. How much each of those things matters depends on the kind of music you listen to, which is, IMO, the most critical thing.

Anyway, here is a follow-up post by Uncle Erik I was meaning to add to this blog.

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Originally Posted by Uncle Erik /img/forum/go_quote.gif Justin, the Millett Hybrid is a fun little amp. I built one a few years ago and I like them. Like Boomana pointed out, amplification is not about power. If we want to go with a car analogy, a 500HP car might sound impressive. But if it has cable-operated brakes and not much suspension, it isn't going to be much fun to drive. An amp is also the equivalent of the brakes and suspension of a car. Personally, I'm into handling. My last car was a dead stock RX-7. Its braking and handling let me demolish cars with much more horsepower. The current car is a stock tC with TRD suspension. Again, the brakes and handling let me outrun a SUV with twice the horsepower. Part of the problem is that people really do not understand what amps do. An even bigger problem is that people make no effort to understand what an amp does. They buy on hype and word of mouth without understanding what they bought. Finesse has a much bigger role to play than simply the power output. One amp I'm building (when I am not stuck in the office as I am today) is a fairly low powered item with 417A tubes. However, it has a slick, smooth power supply and wonderful Lundahl output transformers. The power supply is tube rectified and has three chokes to ensure smooth, ripple-free DC to the circuit. In addition to the tubes and output transformers, it only has one cap and one resistor in the amp circuit. I'm putting in a stepped attenuator, as well. The parts for this amp ran just about $1,100, not including the case. It'll probably be $1,500 total when complete. If I bought large quantities of parts, I might be able to get costs down to $1,200 or so. It is not cheap to build a quality amplifier. I don't know of any other way to get a power supply this good for less - otherwise, I would have spent less. If you factor in labor, tools, overhead, taxes, and every other business cost, it would be tough to make a profit on an amp like this for less than maybe $3,000. Performance aside, you also have to look at reliability and build quality. Sure, you can find some cheaper transformers, but how much will you save if the insulation on the coils melts and you have to replace it? Not all iron is created equal and you might very well have a reliability issue if you shave dollars. I also believe in solid construction. I spend a lot of time digging out individual terminal points out of a electronics store. For those, you have to drill a hole then mount the point. They're individual points, so you need two to mount a resistor. Some might call this overkill. However, if a capacitor goes bad, I can have it out and replaced in 10 or 15 minutes. If you use a PCB, that can take considerably longer and might not even be possible if the PCB scorches and destroys some traces. Then, you'd be stuck with either replacing the PCB or performing heavy surgery that will take hours and hours. Anyhow, if you want something that performs well and is long-term reliable, you have to put time and money into it. There aren't any shortcuts. Someone might be happy with cheap parts, cheap construction and marginal performance, but that is not an excuse to disregard what is good. I just don't think many people here understand what it takes to have a good amp. If they did, we wouldn'thave these kinds of arguments.

 

[cynan]

My simplistic understanding on this: Gain vs Current.

Gain, a function of voltage output, is what is primarily increased when you turn a volume knob clockwise. Yes, some soundcards have sufficient gain to make any headphone sound loud enough - they output sufficient voltage to do so.

However, this does not mean they are able to provide the current to reproduce the enitre breadth of the frequency range evenly or with fidelity. Because lower frequencies require more power (as in VxI or watts) for reproduction, lower powered amplifiers generally result in an under-emphasized lower frequencies (or over-emphasized upper frequencies, depending on your perspective). It still sounds loud, but obviously less full and natural. Once you really start pushing the gain past what the amp can provide necessary current for, you get detectable distortion and, in extreme cases, clipping.

Taken outside of head-fi for a moment, cheaper audio receiver companies often set their gain to match or beat more expensive higher powered models (which are capable of providing more current). An unenlightened customer in a generic box store might be prone to test two such receivers side-by-side by rotating the volume knobs to a given position and think that because the cheaper receiver was as loud or louder at that position that the receiver had as much or more power - when this is absolutely not necessarily true. It's the same with soundcards and better headphone amplifiers...

Of course there is much more that goes into a highend head phone amplifer (or any amplifier) than power (current available at a given gain or voltage output) such as loop back circuits to reduce voltage swing, different input and output stage designs, the use of various tubes and OPAMP, etc... But what is most pertinent to this topic, IMHO, is the old gain vs current issue.

That asside, there are some nice inexpensive PC soundcards coming out that can generate some decent sound on most headphones. Take a look at the new Asus Xonar Essance STX for example.

 

[Currawong]

That's a nice summary I reckon cynan.

 

[Crazy*Carl]

The problem is there are many posts that say higher impedance headphones cannot be driven with an ipod or onboard sound. This leads newcomers to false ideas about what amps are for (like you can not get sufficient volume without an amp, which is usually false). You really have to take these forums with a grain of salt and rely on what you hear (though its hard to demo good equipment.)