[ftb]

In advance, I really appreciate the time anyone takes to help me with my probably stupid questions.

I understand a DAC to be a chip (or stand-alone device) that converts a digital signal into an analogue one to be fed into normal audio equipment. So computer sound cards have them, mp3 players have them, etc, which is why you can plug headphones straight into them and get sound straight away.

Which brings me to not understanding why you buy extra DACs, plug them into your sources, and have better sound. If the source has already converted it into a final signal, why would the signal you get out of your extra DAC you plugged in be any different, unless it's changed or added something to the output signal of the source? Wouldn't another DAC only be useful if you bypassed the first DAC being used in the source? - which, as I understand it, you are not doing by plugging an external DAC into the output of your laptop soundcard and then listening to your headphones from that DAC?

I'm obviously missing something, so please enlighten me

 

[Fryguy8]

Many sources also have a digital output (toslink, digital coax), or are used via usb on computers.

The dacs that you buy are better than the ones you get included with stuff, so by bypassing it and passing a digital output into the separate dac, you get better sound.

 

[Drubbing]

Quote:

Originally Posted by ftb /img/forum/go_quote.gif Wouldn't another DAC only be useful if you bypassed the first DAC being used in the source? - which, as I understand it, you are not doing by plugging an external DAC into the output of your laptop soundcard and then listening to your headphones from that DAC?

With USB DACs this is exactly what it does - bypasses the onboard sound card. I don't know of any external DAc that has a connector that goes straight into a soundcard output, but there may be some.

 

[Rhinosaur]

Quote:

Originally Posted by ftb /img/forum/go_quote.gif Wouldn't another DAC only be useful if you bypassed the DAC being used in the source?

This is exactly what an external DAC does when hooked up to a computer. You stop using the laptop's internal soundcard altogether, and let the external DAC take over.

As the DAC needs a digital signal, you can't plug it into the headphone jack on your laptop as it outputs an analogue signal. Instead you'd plug it into a digital out e.g. the spdif jack on your laptop or via USB. The DAC would then convert the digital signal into an analogue one, which would then go to an amplifier and then to your headphones. A sound card does the same thing but inside your laptop, and outputs that amplified analogue signal via that headphone jack.

Someone will undoubtedly be able to explain this better than I did, but I hope this helps.

 

[krmathis]

An external DAC can give you:
* Higher sound quality (different design, parts, isolation, ...).
* More flexibility (different input/output connectors, balanced drive, use with different transports, ...).
* Different features (Oversampling/non-oversampling, High-resolution (24-bit/92khz, ..).
* More?

You always bypass the transports built in DAC when using an external DAC. Aka -> using digital out.

 

[wuwhere]

For example, the old iRiver iHP-120 or 140 has an optical out, a coax out, a line out, and an HP out. If I use its HP out or its line out , I'm using its internal DAC, which is old and not as good as the newer DACs. If I use its optical or coax out, the digital signal does not go through its internal DAC and I can feed it to an external DAC/AMP which in my case is an iBasso D10. The sound is much much better through the iBasso D10.

 

[iszatso]

Are many running the line out to the D10? Haven't heard many doing that. Almost all use optical. If using coax what cable would you recommend?

 

[mrarroyo]

We buy external DACs with the hope they sound better. Occasionally they do and sometime they do not. Part of the research is how to feed the external DAC including the use of a re-clocker. Since there are a few variables it is not an straight process which at times gets both expensive and counterproductive.

 

[itsborken]

When you put a dac between your source and your amp, you are bypassing the builtin dac of the source completely (if you were using the analog out of the source you would have used the builtin dac). So a coax output of the source goes into the coax in of the dac and then you take analog out (rca or xlr) to your analog amp inputs.

Basically people bypass the builtin dac when it doesn't provide as much clarity, attack/decay of notes, instrument separation, overall soundstage width and depth, etc. Pianos and cymbals may not sound quite right and a replacement may correct the issue. Others buy a dac to take some of the edge off of digital crispness if they prefer a more euphonic sound. So, it depends on what type of sound the listener wants to generate as far as if the stock dac works out well or not.

 

[wuwhere]

Quote:

Originally Posted by iszatso /img/forum/go_quote.gif Are many running the line out to the D10? Haven't heard many doing that. Almost all use optical. If using coax what cable would you recommend?

I do, I feed my D10's line out to my Pico amp. It's a fix output. I have not ever used my D10's coax in.

 

[Happy Camper]

So the next question is why is the external DAC better than the DAC on your computer?

power supply

The power supply is the heart of any device. In a computer, it is shared with the rest of the machine. An external DAC will have different levels of design and quality parts. The better designed DACs are building external power supplies for the DAC to keep any RF and mechanical noise from transformers out of the signal processing area. You can imagine the sources of noise inside a computer.


circuits & components for output of the analog signal

The method for taking the analog output of the DAC chip and amplifying it to use with audio gear is where there are many options and claims of distinction with different designs. The computer is putting out a signal that is used with a cheap headphone amp circuit in the soundcard. A better quality signal is the line out of the soundcard. It doesn't degrade the signal by going through a cheap amp but still is so-so . External DACs will have much more circuitry and quality parts to make the sound better.

ability of the design to manage information

This is an area that I won't try to explain except to say the reader sends information to the DAC for processing. This information includes music and timing data. Getting that data put back together properly has a lot of designers doing many different methods to make the claim of better DACs. The more expensive DACs use many DAC chips in the design.

If I run across an informative DAC discussion, I will link.

 

[ftb]

Thanks so much for all your informative replies, guys. My initial confusion is no more. I didn't realise using the other connections like USB, coax, etc, bypassed the internal DAC. There sure is a wealth of knowledge on this forum