[ag8908]

Edit: DO NOT TRY THIS. See my experience here http://www.head-fi.org/products/breeze-audio-pd05-xmos-pcm5102-dac
 
As I understand, perhaps the most important determinant of how a DAC sounds is its chip. Higher end DACs have very fancy chips, 32 bit 384k etc. Lower end DACs don't. Each chip also has its unique sound signature. So . . .
 
1. You can go to this website, or another, to find the DAC chip used. http://www.alldacinfo.com
 
2. For example, the very expensive Foxtex HP-A8 uses an Asahi AK4399 chip http://www.alldacinfo.com/?p=7383. Or, the expensive Luxman DA 100 uses a Texas Instruments PI5102 http://www.alldacinfo.com/?p=8532 .
 
3. Then you can search ebay for DAC [chip], e.g. search for DAC ak4399 http://www.ebay.com/sch/i.html?_trksid=p2050601.m570.l1313.TR0.TRC0.H0.XDAC+ak4399&_nkw=DAC+ak4399&_sacat=0&_from=R40 or search for DAC PCM5102 http://www.ebay.com/sch/i.html?_trksid=p2050601.m570.l1313.TR0.TRC0.H0.XDAC+PCM5102&_nkw=DAC+PCM5102&_sacat=0&_from=R40 to find USB DACs already assembled, containing that particular chip.
 
Will these sound significantly different from the pricey versions?

 

[jodgey4]

I've always heard that while chips have their differences (including or not different filter options), the most important part is the actual analog stage after/implementation of the chip. I would not buy a DAC on a chip alone.

 

[Chodi]

Those selections you posted from Ebay are sure cheap but are they real? There are a lot of fake parts coming out of China. Even if the dac chips are real that does nothing to validate how they would sound in the circuit provided. I admit the cost is so low that it is not a high risk to try one and see if you like it. Seems they are selling some of those DIY boards for less than the known cost of the components (if real).

 

[RonaldDumsfeld]

Each chip also has its unique sound signature

 
Does it? Really? I thought that in any form of objective test all competent DAC assemblies sound the same i.e. transparent to the human ear.
 
Some measure better than others and don't quite measure as well as they should but no one has ever proved they can hear clear differences. As far as i am aware.
 
The reason you can get knock off copies of 'hi end' gear so cheap is precisely because the current generation of converters in motherboards, smartphones and tablets is so good and inexpensive.
 
.

 

[ag8908]

Yes I'm almost certain each dac chip had its own sound signature.all mine do (although I guess I can't prove it's the chip and not some other part of the dac)

 

[ag8908]

  Those selections you posted from Ebay are sure cheap but are they real? There are a lot of fake parts coming out of China. Even if the dac chips are real that does nothing to validate how they would sound in the circuit provided. I admit the cost is so low that it is not a high risk to try one and see if you like it. Seems they are selling some of those DIY boards for less than the known cost of the components (if real).

But are the components in a DAC that expensive? Mechanically or from an electrical engineering perspective it's not necessarily the most cutting edge of technology is it? The chip is the most sophisticated/complex part of the structure if I understand correctly.

 

[]eep]

As I understand, perhaps the most important determinant of how a DAC sounds is its chip. Higher end DACs have very fancy chips, 32 bit 384k etc. Lower end DACs don't. Each chip also has its unique sound signature. So . . .

...moot...

Will these sound significantly different from the pricey versions?

I have compared quite a lot of dacs by now.

You are starting from a right (but flimsy) proposition using faulty premises and thus ending up at the wrong conclusion. And so you are asking the wrong questions.
Yes, a dac chip is important. But it heavily depends on how it is fed, implemented, filtered and amplified. In my opinion what happens after the dac chip determines most of the sound. You can use the most advanced chip using the highest samplingrates (why is/should 32/384 be audably better than 24/96?) but if you filter to early or to steep and use (cheap or knockoff) opamps you will not attain the same quality as that high-end dac that uses the best input (chip+protocol to avoid jitter), the best powersupply and discrete filtering and I/V conversion.

I love nothing better than finding a cheap version of high priced high-end stuff, but there are may caveats. There are lots of great products coming from China, but you cannot trust any or every Chinese seller that comes along. Often they will sell samples that did not pass QC. I know, I'm getting quite an expert in purchasing from China (>7y). You have to know more about audio than just what chip they use. There are many variables, not just technical. I buy as many dacs as I can from China, preferably the cheap promising type, and see what can be modified. My biggest success is also the cheapest and simplest dac. I own several types and compared them with others types and output filters. I organize meetings for ppl to listen to as many different dacs as we can find. My favorite is still the simples NOS dac. Second comes my heavily modified tubed sigma-delta dac. Another good dac I heard was a very expensive Lampizator DAC. I can't really compare with what I heard in shops and shows since amps and speakers have to much influence. My biggest disappointment was an SMSL dac with, what I thought was, a very good dac-chip and decent opamps. Sound was disappointing. And when I started swapping opamps it started eating opamps and finally broke down completely without ever living up to its promise.

My NOS-DAC uses a cheap bulk chip that keeps 100% of the signal-quality while a good SDdac might produce a 'better' signal but loses all or most of it's advantage to the outputstage. SD dacs produce a lot of high frequency noise that must be filtered why NOS dacs do not (not much). SD-dacs are made for cheap and easy production and need amplification of their very weak (V) output signals (hence I>V).

So, my advice: start by leaning about the differences in conversion methods, fi nos or ladder-dacs vs. sigma-delta dacs, output filtering and amplification. Avoid opamps. And then start looking around.

Edit: another caveat: Chinese love name-dropping. They think it sells if there are a lot of expensive names in the product description. The more the better. They have no idea how to make it sound good though.

Edit 2: This is my educated guess for a good dac. I was thinking about the VALAB version, but it's not really that cheap (and my wallet to thin).

 

[ag8908]

links to these good cheap dacs you found?

 

[]eep]

The ones I modified?
Without my mods it's just average (with limited lifespan).

 

[FraGGleR]

The DIYinHK boards have gotten good reviews in the DIY circles.  They aren't the cheapest, and you would have to DIY quite a bit, but if that is what you are looking for, that could be a good place to start.  
 
And not everything from China is a cheap knock off.  Direct access to factories can give some of these small board makers quite an astounding price advantage, not to mention that their response to insane amounts of competition is to reduce margins (instead of shoot for premium markets).  I recently traveled there and marveled at how cheaply things can be made and gotten.  Little standoffs that would cost me $0.30 a piece from Mouser were available for parts of a penny (granted I would have to buy several hundred...).  I will concede, though, it is near impossible to sort through the cheaply or poorly made boards and the good ones, but that is the risk that you take trying to get around paying for branding, R&D, labor, distribution layers, etc. that you get with name brand stuff.  Again, not saying stuff from China doesn't come with extra caveats, just don't like to see the sweeping and borderline xenophobic claims that all things Chinese are sh!t that pops up quite a bit (not specifically this thread).  
 
And to reiterate what others have said, the DAC chip itself won't tell you anything about how it will sound.  It is all about the implementation of the surrounding components and for that, you will have to really know DAC design to sort through it all.  If that isn't your strength, I'd just save up money to buy a well reviewed DAC that meets your budget and needs.

 

[ag8908]

The ones I modified?

Without my mods it's just average (with limited lifespan).

oh i see n/m.

 

[Bobby S]

As already mentioned, the DAC chip alone plays a minimal part is the final sound of a product.
There are dozens of DACs out there based around the same chips and some can sound dramatically different to others, just in terms of character.
In terms of quality the differences can be even more stark.
Long story short: it is unrealistic to expect a cheap DYI board sold for peanuts to sound similar to a mega-buck DAC from Luxman or whatever company.
 
Here are some of the technical traits of a high quality DAC:
- extremely low jitter, obtained by employing high precision clocks (expensive!)
- high quality interfacing for SPDIF and/ or USB (asychronous, galvanically isolated etc, again expensive and hard to do)
- high quality power supply, for clean, low-noise power to all components (very expensive)
- high quality discrete analog stage (difficult to design, expensive to implement)
 
Even for a minimalistic design of such a DAC, the parts alone cost in the hundreds of USD, not to mention the extensive time required for R&D to come up with it in the first place.
Long story short: there are no free lunches.
 
On the other hand you can get 80-90% of the way there with cheaper solutions, that is true. And for that reason alone the Chinese DACs have become extremely popular in the last decade at least.

 

[ag8908]

Being a gambler, I just pulled the trigger on this. Basically not returnable. Wish me luck!

http://www.ebay.com/itm/PD05-XMOS-PCM5102-USB-DAC-with-Headphone-amplifier-fuction-SN-/121284312100?pt=US_Home_Audio_Amplifiers_Preamps&hash=item1c3d1bbc24

It has what I heard is arguably the best chip out there Burr Brown (Texas Instruments) PCM5102 384k/32bit.

 

[FraGGleR]

Being a gambler, I just pulled the trigger on this. Basically not returnable. Wish me luck!

http://www.ebay.com/itm/PD05-XMOS-PCM5102-USB-DAC-with-Headphone-amplifier-fuction-SN-/121284312100?pt=US_Home_Audio_Amplifiers_Preamps&hash=item1c3d1bbc24

It has what I heard is arguably the best chip out there Burr Brown (Texas Instruments) PCM5102 384k/32bit.

Please let us know how it goes.

 

[Chodi]

Honestly, if you want a very reasonably priced product from China with service and a good reputation for building products that sound good I would go to Audio-gd. Their products are all reviewed and you know what you are getting. I admit at the price for these no name china products the price is low so there is not much risk. I would be interested to hear your results. Just because it has a the same dac chip as an Audio-gd, Yulong or even Benchmark dac doesn't mean it will sound and perform anything like those.