Audiophile equivalent of “hack value”?
I don’t really see how it’s so difficult to understand. We do pretty much the same thing.

This is just a guess, but I believe that the distortion is of the agreeable type. Every tube amp owner I’ve know spoke highly of the “warm” sound that was produced. They aren’t “flat” response.

I’m just saying this would make more sense if it was for a purely analog system, like a phonograph or audio tape. Pumping digitally-represented tunage through an analog amp seems like tubes for tubes’ sake at best, an exercise in futility at worst.

Mike please no audiophile crap, go for ufo and paranormal if you chose lunatic direction just not audiophiles please

I sit here with my HifiMan EF2 ($200) and Audio-Technica ATH700 ($140) connected to my PC and I’m enjoying great audio while I work. I switched from a Creative X-Fi and I have to say, unless you listened to the difference, you would not get it.
The EF2 (available at head-direct dot com) is connected to my PC via USB and has no audio driver at all on my system so the MP3, WMA or better yet, FLAC files play on media monkey and out my USB as digital and are decoded on a Digital to Analg converter (DAC) inside the little amp. The DAC alone adds great value as it is much better quality than Creative uses in their process and it does not pick up system noise from being inside the PC. Then the sound goes through two vaccuum tubes and it amplified a bit and naturally picks up that warmth of sound that everyone who listens to tubes, enhjoys. Then it is boosted by an output section whhich gets it to the level and impedence of my headphones. So for under $400 I have sound which is in a lot of ways as easy on the ears and as rich and full in depth and soundstage as an expensive home system with regular speakers.
If you get a chance, go visit head-fi DOT org and see all the different equipment the members have and talk about. It is an enjoyable site to learn about headphones and amps.

@therian:
Who cares?
Just be glad that it’s a decent electrical project and not a wallet made out of broken Arduino boards or something.

Being an audiophile is different to everybody. It’s all about getting exactly the sound you want. If you want precisely the sound that the producer and creator intended, then that’s what you should pursue. Same for if you are looking for something that does not have perfectly flat frequency response, but just that little something that works for you.

If it is not your deal, then do your own thing.

Great project anyhow, new technology is great, but the old stuff can be just as fun!

Tube have distortion in the even harmonics while op-amp have it in the odd harmonics. Odd harmonics are those making a square wave, so they are ‘unpleasant’ to the ear. Even harmonics, on the other end, make for a softer sound. Tube also require less feedback, which is good.
On the other end, using a tube amp to listen to digitally butchered music (aka MP3) doesn’t make much sense to me…

I’m going to build a “tube” amp like this but put a cheap IC amp inside with a LPF to cut out the highs. It’ll sound the same to these tube-stricken “Audiophiles”, nice and “warm” – at least as long as it glows.

Serge747 has no idea what he’s talking about. He especially doesn’t know what harmonics actually are.

@ riazap–
You are not being fair to @Serge747. He is essentially correct. The “warmth” attributed to vacuum tube amplifiers and audio gear stems from the type of distortion they tend to introduce. If you know anything about music theory, you know that doubling the frequency of a tone brings you up one musical octave. So, for example, if your fundamental is 440 Hz (an “A”), and distorion causes even harmonic content at 880 Hz, it still sounds good, because the harmonic is pleasantly and musically-related to the fundamental. This is true for all of the even harmonics.

Tubes are not the only pieces of audio equipment that exhibit this tendency. For years, studio engineers ran their tape decks “hot,” purposefully recording above the recommended 0db level so as to introduce even harmonics that “fattened” the sound.

Solid state gear tends to produce odd harmonics. These harmonics are *not* musically related to the fundamental, but are instead dissonant. Distortion with odd harmonic content tends to sound harsh.

An exception to this is FET circuitry. FETs are voltage-controlled devices, as are tubes, and if they’re set up right, and driven into distortion the right way, they can have remarkably tube-like audio qualities.

Another thing that @Serge747 touched on is the idea of feedback. Modern amp design usually involves building an amplifier with huge amounts of gain, then taming that gain with negative feedback. The benefit, among other things, is improved bandwidth. Vintage tube audio tended not to have a great deal of negative feedback. If you feed both types of amplifiers with percussive, narrow-pulse audio (as might be found in a snare crack, or the ting of a ride cymbal) audible differences appear due to the time constants associated with the feedback network in the solid state amp.

The bottom line is this: It seems to me that a lot of what passes for “audiophile quality” equipment and accessories really boils down to an “I-have-a-bigger-d*ck-than-you” type argument. In other words, it’s BS. I’m not convinced that a $10,000 amplifier is 100 times better than a $100 amplifier, and the way most people use them, you would never hear the difference.

However, that doesn’t change the fact that there *is* a difference between the way tubes and solid state devices process sound, and there are legit reasons why one would purposefully choose tubes.

One final comment. There is no such thing as “reproducing” music. Why? Because no snare drum in the real world sounds like the snare drums you hear in pop music. Those drums are gated, filtered, and usually processed with one or more types of reverb. A real electric guitar doesn’t “sound” like much of anything at all. In fact, an electric guitar is really a kind of analog synth, because it uses the vibration of steel wires in a magnetic field to produce disturbances in a coil of wire. The signal that comes out of that is amplified, compressed, gated, clipped, and processed with chorus, delays, reverb, and who knows what else. Even the singing you hear in a recording is *not* how a real-life singer sounds, unless you are used to having people sing full-blast within 4 inches of your ear.

My point is that music, from the moment of creation, is really a *subjective* expression. When that recording is later played on your ipod, a car stereo, a boom box, or whatever, it is further altered and modified, intentionally or not, by your space, your equipment, and your settings.

The ambiance of the space between your ear-buds and your ear drum, or in the passenger compartment of your Nissan, is not the same as the ambiance in Carnegie Hall. Even if it was, *nobody* can seem to keep their hands off the bass and treble controls. Then there are those numb-nuts who drive down the street with the volume so high that their own eardrums are being driven into distortion. Accurate “reproduction” my *ss!

Music, from creation to delivery is entirely subjective in nature.

Pfft, so you did a bit of study and have no real world experience? If you think you know better, how about explaining why you disagree.

Nicely put pookeye.

@samurai

Power and efficiency are irrelevant at experiencing music. Some people pay insane amounts of money to listen 1kW+ power amplifiers on 80dB/W or less efficient loudspeakers. Other people make 3-5W power amplifiers and use them on 90dB/W or more efficient loudspeakers. Truth is the human ears can’t listen music louder more than 85dB for long periods of time without suffering permanent damage.

Distortion level (THD) is number that describes level (amount) of distortion, nothing more. It does not describe how brain perceives distortion, so it is more a number for the magazines than guidance for the pleasure.

Hearing is believing, and goes double blind-folded for audio.

It induces noises and glows lights. It’s also a space heater!

This monkey is satisfied!

@DontBuyFromLogitech

or one of the Creative PMPs that natively play FLAC?

iFanboi…

I dare you to find a single person that can tell the difference between a FLAC rip done from a mint vinyl record, and the vinyl record itself, given the exact same full-analog setup (after the point of phono-preamping or flac->dac).

I guarantee any properly-sized trial will yield no better than random (.50/.50) at picking out the source of audio.

@ RandomPrecision I believe person named Carver was acknowledge with duplicating the sound of tube audio amplifiers with transistor amplifiers. He’s know dummy, where there are few who want to buy transistor amps that sound like tube amps he manufactures high end expensive tube amps as well. Used to anyway it’s been a long time since I pay close attention to the audio entertainment world. My 30 year old Radio Shack system still works well.

I came up with a rather simple rule, many years ago, after working in a high-end stereo shop for a while and having people come in who basically wanted to buy equipment that distorted music in some particular way that they claimed to ‘like.’

Whether it was JBL speakers with the once-popular ‘west coast sound’ (basically pumped-up midrange) or Empire phono cartridges with certain definite frequency limitations, or even people who wanted to use equalizers to minimize trumpets or whatever, my rule came to be “get equipment that reproduces as accurately as you can afford, and if you don’t like what you hear, then you need to listen to different music.”

@ Whoever

THIS.

(Very nice post, man.)