Does an expensive DAC make a difference?

Q: Does an expensive DAC make a difference?

A: Most sigma delta DAC chips sound so similar it is hard to tell them apart. The sound the DAC puts out is also influenced by the analog circuitry, which may or may not be significant. Since many DACs try to be "transparent", i.e/ to add or take away nothing from the signal, you are not going to see a huge difference between them, despite their cost. So for example an ODAC sounds very similar to a Benchmark DAC1.

There are 3 exceptions:

1) some manufacturers go our of their way to "tune" the sound of their dac, typically by using the analog circuit to modify the sound, for example the warm sound of the Cambridge Audio DACMagic 100 or the Micromega MyDAC.

2) An NOS DAC often sounds very different than regular sigma delta DACs, mainly because the DAC chip itself i very different.

3) Some DACs add a filter to the output stage to modify the sound. This filter can be a tube, for example the Aune T1. The tube does not really act as a tube (i.e. for amplification) but serves to distort the signal in a pleasing way. Therefore these DACs sound different.

So it's not the price of the DAC per se, but which category it falls under that ultimately determines the sound it generates.

In general headphones and amps make much more different to sound than DACs. But DACs make a bigger difference than cables.

DAC vs DAC

Q: Do DACs really sound that different from each other? I thought all DAC chips sounded pretty much the same

A: Most DAC chips are indistinguishable from each other, but keep in mind that DACs have analog circuitry too, which changes the sound to a lesser or greater degree.

So for example I cannot tell the difference between Modi and ODAC most of the time but I can tell the difference between my NOS DAC and ODAC every time!

And between my Cambridge Audio DacMagic 100 and Modi every time (different analog circuitry specifically tuned by Cambridge Audio to sound warm for classical music)

USB vs optical vs coaxial inputs

Q: What is the difference between USB and optical/coaxial inputs? Is one better than the other?

A: In essence they are the same -- a digital signal is a digital signal, no matter how you transport it. Having said that, there are a couple of differences:

[1] if you use USB, you can plug it into any computer. With optical or coax you need a source with an optical or coax jack. Not all computers have them, for example.

[2] At one point until not so long ago, USB technology was limited to 24 bits/48 kHz. At that time, it was much more advantageous to use optical or coax, which went up to 24/96. That technological disadvantage is no longer the case with current generation of USB chips. However, the technology has swung the other way -- many DAC manufacturers limit optical/coax thruput rates to 24 bits at 96 or 192 kHz. If you want to go higher beyond 192 kHz, for example 24-32 bit/352.8kHz-384kHz, USB may be the only way to do this. Keep in mind that your ears probably cannot tell the difference between 24/96 and 24/192.

[3] If you want DSD you may have to have USB input (of course, if your DAC does not support DSD then this is moot)

[4] if you have USB line noise from EMI (because USB carries power in addition to the audio signal) then optical/coax may get help rid of the noise (because you are not using USB)

Personally, my favorite connection is optical out, and not for any musical reason -- I just like the idea that my music traveled along a fiberoptic cable as light before ending up between my ears.

Now I see it, now I don't....

Q: Do different DACs sound different? What kind of DAC should I get?

A: In theory the DAC should generate the exact identical analog version of the digital source, i.e. the sound is faithfully transmitted to the next link in the chain without any additions or subtractions. This is my definition of a transparent DAC --- a DAC that behaves "like it's not there".

But in reality that's not what happens, since the additional components that make up the DAC add their own "voices" to the signal, as does the DAC chip itself.

Having said this, most DAC chips use the same digital processing method (delta-sigma) and so sound remarkably similar to each other, whether they are made by Sabre or Wolfson or Cirrus Logic or Analog Devices, or any of the other slew of DAC manufacturers. There are some exceptions, for example old-style NOS (non oversampling) DACs sound different than their delta-sigma brethren, because they operate under entirely different principles.  But by and large when you read reviews that wax eloquent about the significant and substantial differences in the sound from one DAC chip or another, you are being subjected to, well, bullshit.

Why then is there so much variation recorded between DACs? Why are some dacs felt to be "warm" and others to be "cold"?  Well, the biggest reason is that it is a matter of perception: if you approach DAC transparency from an objectivist position, then for you a transparent DAC is ideal and if you are a subjectivist listener then the same DAC is "cold" or "boring".

If you are an objectivist, you want the faithful transmission of a signal, then the coloration imparted by the analog component fo a DAC like the Cambridge Audio DacMAgic 100 is anathema.

And if you are a subjectivist, the coloring of the sound excites you just as much as the faithful transmission of the signal, and the transparent output of a DAC like the ODAC might be "bland" or "cold" or "not energetic" to you. I would argue that for such a subjectivist listener, the tonal variations offered by a tube DAC might actually be more pleasing than "the truth the whole truth and nothing but the truth" offered by a transparent DAC. If you don't believe me, ask anyone with a Grado.

Further, a DAC can pick up floor noise -- hiss from, say a laptop via the USB port, that the muddies the sound profile a ta. But the same DAC may be deathly silent when plugged into a desktop USB. Does that mean that the DAC is transparent when it's connected to a desktop but not to a laptop? By my definition, yes.

You can get around noisy USB by including a good power transformer with the DAC itself. But these are expensive, and can drive up the price of the DAC. One DAC brand that has been touted for its sonic neutrality, to the point of becoming a standard reference whenever the term "transparent DAC" rears its head, is the Bench mark DAC1, which is an expensive option.

So from price-performance perspective, does buying a DAC1 make sense? Probably not. You can get a relatively transparent DAC as cheaply as $100 - the Schiit Modi (which uses a wallwart for power), or alternatively the ODAC (which uses USB power, and is priced at $150) and these are perfectly acceptable price-performance options to something like the DAC1.

Q: Can DAC s power headphones?

A: Some DACs have circuits on their output side that can run most headphones without issues -- for example the Benchmark DAC1 is a reference DAC that also has a high current, low impedance headphone amp. Now you can use it as a DAC with fixed output to a standalone amp, but in reality you could use it as the only equipment you will ever need, if you wanted to. The HPA2 on the DAC1 is very capable of powering 2 headphones on its dual outputs, including most higher impedance headphones. The volume knob allows you to easily adjust the level of the output, and so you can set your source volume at 100% and use the DAC1 to pretty much manage your entire personal audio experience.

In contrast, you have the Schiit Modi, which outputs a line-level signal via the RCA jacks on the back. The Modi output may not be powerful enough to power many headphones, and you have no way of adjusting output volume unless you modify the source level (which is typically not the best thing to do since the sound quality can degrade).

So the trick, if you want a single unit solution, is to find a DAC/amp combo, or a DAC that has a headphone amplifier circuit built in. Keep in mind that some lower-end DACs don't really splurge on the quality of the built-in headphone amp since they don't see the need (many of their customers will be using standalone amps anyway).

Aune Flew Over The Cuckoo's Nest

Q: So I recently bought an Aune T1 and upon trying it out for the first time I realized that the sound cuts out every few seconds for about 1/4 to 1/2 a second. After further listening I discovered that the amp completely disappeared from my computer's list of playback devices after about 5 minutes. I've tried plugging it into different USB ports on my motherboard, and even tried a different USB cable but I keep getting the same issue.

A: The Aune T1 is a budget option that has had its share of reliability issues.

If the sounds cuts out intermittently for short periods, the first thing to consider is distortion known as clipping (which occurs when an amplifier is driven to excess, and tries to output more than it can), but that should not cause you to lose the USB connection.

It does not look like the issue is a bad USB port on your motherboard.

I would first go into computer>properties and prevent your USB from sleeping. If the issue still exists, try connecting the Aune to a different computer. The T1 has a Tenor USB chip that should be plug and play. If it intermittently loses connection with all computers, I think you might have gotten one with a bad chip.

If it works well with a different computer, I would reload Win drivers (or try running the T1 with ASIO drivers)

Veni's Three Laws Of Cheap (But Good) Personal Audio

Q: Whats the easiest way to improve my listening experience on a low budget?

A: There are three components that folks typically consider when they talk about personal audio -- [1] headphones, [2] amplifiers, and [3] DACs (digital to analog converters).

Veni's Three Laws Of Cheap (But Good) Personal Audio are:

Law 1: in general better headphones improves your sound the most, more than upgrading your amp, which in turn offers more enhancement than improving your dac.

Law 2: not all headphones need a dedicated amp or DAC.

And finally Law 3: if your amp or DAC costs more than your headphones, you are probably doing something wrong.