rather confused

Laptops don't have the best sound quality, normally. It's not a priority, and as small as many laptops are for what they have inside, there's usually not enough room or concern for proper shielding. The result is a high noise floor, hiss, and opamps that probably aren't at all optimal for the circuit. Macs, I would hope, have better sound than Dell laptops, because Apple puts an emphasis on art when it comes to selling their computers.

Portable players, and smart phones as well, put more emphasis on sound. More money and effort is put into designing the DAC and amp, and more care is taken to ensure proper shielding, channel separation, etc. It's really no surprise you don't hear a difference, not to me anyway. It's pretty easy to find a DAC with inaudibly good performance, and with a headphone as easy to drive as a Grado it's no big deal to find an adequate amp either. The big concern for low impedance headphones is output impedance, and sometimes THD. Power isn't an issue unless output impedance is high, even with portables.

There's also the fact that the uDAC-2 isn't a very good piece of equipment, even for its price. Though I'm unsure of the Galaxy S specs, it's entirely possible that its amp outperforms the uDAC in certain tests, particularly channel balance and output impedance.

The udac-2 uses the ESS Sabre 9022 DAC and your Galaxy uses the Wolfson WM8994.  The primary differences are outlined below.

ESS Sabre 9022 DAC is a 32-bit DAC chip while the WM8994 is only 24-bit

ESS Sabre 9022 DAC  is a 8-channel chip at while the WM8994 is only a 4-channel chip

ESS Sabre 9022 DAC has an upsampling rate of 864 khz while the WM8994 samples up to 96kHz

The audible differences will depend on the rest of your setup.  What sample rate you are feeding the different DAC chips, the various bit rates on both the files and the devices you are using.

With your current gear it looks like you cannot hear a major difference.  There may or may not actually be an audible difference, but a more in-depth analysis must be done to conclude there is no advantage of one over the other.

Quote:

Originally Posted by NA Blur 

The udac-2 uses the ESS Sabre 9022 DAC and your Galaxy uses the Wolfson WM8994.  The primary differences are outlined below.

---

ESS Sabre 9022 DAC is a 32-bit DAC chip while the WM8994 is only 24-bit

 

ESS Sabre 9022 DAC  is a 8-channel chip at while the WM8994 is only a 4-channel chip

 

ESS Sabre 9022 DAC has an upsampling rate of 864 khz while the WM8994 samples up to 96kHz

 

The audible differences will depend on the rest of your setup.  What sample rate you are feeding the different DAC chips, the various bit rates on both the files and the devices you are using.

 

With your current gear it looks like you cannot hear a major difference.  There may or may not actually be an audible difference, but a more in-depth analysis must be done to conclude there is not advantage of one over the other.

Very little of that matters on its own, and is overshadowed by the design itself. It's misleading to simply quote the chip info, especially stuff like 32-bit versus 24-bit which doesn't matter at all.

I have not had a chance to listen to the UDAC-2, but perhaps you could elaborate as to why you do not like this piece of equipment?  Do you have any measurements as to why it does not perform as well as other DAC's?

 

Quote:

Originally Posted by Head Injury 

Laptops don't have the best sound quality, normally. It's not a priority, and as small as many laptops are for what they have inside, there's usually not enough room or concern for proper shielding. The result is a high noise floor, hiss, and opamps that probably aren't at all optimal for the circuit. Macs, I would hope, have better sound than Dell laptops, because Apple puts an emphasis on art when it comes to selling their computers.

 

Portable players, and smart phones as well, put more emphasis on sound. More money and effort is put into designing the DAC and amp, and more care is taken to ensure proper shielding, channel separation, etc. It's really no surprise you don't hear a difference, not to me anyway. It's pretty easy to find a DAC with inaudibly good performance, and with a headphone as easy to drive as a Grado it's no big deal to find an adequate amp either. The big concern for low impedance headphones is output impedance, and sometimes THD. Power isn't an issue unless output impedance is high, even with portables.

 

There's also the fact that the uDAC-2 isn't a very good piece of equipment, even for its price. Though I'm unsure of the Galaxy S specs, it's entirely possible that its amp outperforms the uDAC in certain tests, particularly channel balance and output impedance.

Quote:

Originally Posted by NA Blur 

I have not had a chance to listen to the UDAC-2, but perhaps you could elaborate as to why you do not like this piece of equipment?  Do you have any measurements as to why it does not perform as well as other DAC's? 

Yes. I'll PM them.

Most of the problems are with the amp, though.

I wish I had more DAC's around to do some listening tests, but measurements always help.  Thanks for the data.

Quote:

Originally Posted by hophilip 

Pardon me but i don't really understand the following

"The big concern for low impedance headphones is output impedance, and sometimes THD"

 

My Grados is a low impedance cans, so what i understand is i don't really need a powerful amp to drive it, the small amp in the galaxy s or udac-2 is sufficient to drive the 225i fully. am i correct? So basically the sound quality of my grados can't get any much better as is?

 

"Laptops don't have the best sound quality, normally. It's not a priority, and as small as many laptops are for what they have inside, there's usually not enough room or concern for proper shielding. The result is a high noise floor, hiss, and opamps that probably aren't at all optimal for the circuit. Macs, I would hope, have better sound than Dell laptops, because Apple puts an emphasis on art when it comes to selling their computers."

The above passage don't really matter for my case right? because no matter what laptop i am using, i am still outputting the signal to the external dac/amp which is the udac-2. So my source is currently the udac-2 right?

 

"The audible differences will depend on the rest of your setup.  What sample rate you are feeding the different DAC chips, the various bit rates on both the files and the devices you are using."

I am playing apple lossless files via itunes. 16bit and 44khz sampling.

Correct on all counts as far as I'm concerned. There are some who swear easy-to-drive headphones sound better out of a 6 watt amp, but I don't see why you'd need anything more than good specs and enough power to reach volumes 10-20dB louder than you ever listen.

You can do better, but how audible the difference is will be questionable. I doubt your smart phone is the be-all-end-all of DAC and amp quality, and the uDAC-2 isn't. You can get better measurements, but many will be beyond audibility already. Then there's always the flip side of the coin. You could chase colored amps and DACs, tube amps with high distortion, or any number of subjective things. You'll be paying for technically inferior products, but if that's what you like then go for it.

Your priority should always be the headphones, just make sure what you're plugging them into is good, not necessarily expensive, and you'll be fine.

I think what Headinjury is saying is that if you want to look for the key specs at a piece of equipment for your setup ( i.e. low impedance headphones ) primarily look at the THD% and output inpedance specs.   I do not think he is saying you need an amp for your Grados, rather, he is suggesting some specs you can look at when you buy / browse new equipment.

I think most Mac's have better sound because of two reasons.

1.)  The audio train is almost completely separated from the power / noise sources

2.)  The DAC is simply better in most Mac's vs Windows based machines or at least how the audio is processed is generally better.

Quote:

Originally Posted by NA Blur 

I think what Headinjury is saying is that if you want to look for the key specs at a piece of equipment for your setup ( i.e. low impedance headphones ) primarily look at the THD% and output inpedance specs.   I do not think he is saying you need an amp for your Grados, rather, he is suggesting some specs you can look at when you buy / browse new equipment.

 

I think most Mac's have better sound because of two reasons.

1.)  The audio train is almost separated from the power / noise sources

2.)  The DAC is simply better in most Mac's vs Windows based machines or at least how the audio is processed is generally better.

Nice. I've always thought that Mac machines have decent DACs.

Quote:

Originally Posted by NA Blur 

Here is a link that Headinjury supplied comparing the UDAC-2 to the FiiO

Careful with that link! Open discussion of that blog is still banned as far as I know.

The LCD-2 is a great can.  It is well constructed, looks and feels amazing, a tad heavy for my taste, but sounds great.  I find the Rev 1 a tad dark and the Rev 2 a tad bright at times, but dark as well.  The LCD-2 are a bit clunky too and you will not want to be carrying them around all the time.  The DT990's are much lighter and easier to move around.

If it were me I would first find a really nice pair of headphones.  The 225's are great and all, but honestly you will not be completely exposed to great headphones and thus musicality until you reach up into the AH-D2000/DT990/LCD-2 range.  I find the DT990's really fun because they sound good out of a portable device, they improve with basic amplification, and through an awesome amp such as the m903 they sound amazingly powerful and expansive.

If you wanted to really have a great experience go with the following setup.

256kbps mp3's or lossless formats --> foobar2000 -->  Headroom's Micro Stack  Package --> DT990 ( 32 Ohm )

The Micro Stack Package runs for $675 and I know it is good because their reviewers use it a ton

The DT990's are $320

Foobar2000 is free

Yes I understand this is expensive, but with this upgrade you will certainly hear the difference and should not need to upgrade for many years.

If you plan on using the headphones almost exclusively with the amp then go with the DT990 ( 250 Ohm ) as they would fit the amp better.

To me tube amps just add another expensive part that will need replacing if you can even replace it on the particular amp you end up with.  I listened to a tube-hyrbid amp a while back and it did sound nice, but not any better than say the Ultra Desktop Amp or m903.