YoYo JoKeR

100+ Head-Fier
Pros: Transparency, Clarity, Supreme Performance, Reliability & Affordable to All
Cons: Literally nothing.

Intro:  JDS Labs, Is an American company based in Collinsville, Illinois. They make headphone amplifiers & DAC’s. Mr. John Seaber is the man behind JDS Labs.  We might remember JDS Labs when they produced the popular cmoy-BB amp & later on, their Objective2 which was a game-changing amplifier. JDS Labs has also manufactures their own products: C5/D Portable amplifier/DAC, Element desktop Amp/Dac along with ofcourse their Cmoy BB amp.
Special mention is about my experience with Mr. John. From my experience & interactions with him, he is the kindest & very prompt person I have ever spoken to in audio world. He answers to all questions in person & makes sure doubts are cleared. I’m a proud owner of JDS Labs O2 amp, (my first headphone amplifier, in early days of my Head-Fi days)  Enjoyed it a lot, had a wonderful time with it. O2 holds a special place for my ears.
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My profound thanks to Mr.John for arranging a sample unit of ODAC RevB for my evaluation. The ODAC  got updated in circuit board. The latest model is ODAC Revesion B, improvised on previous & original design of ODAC. So ODAC Rev.B is basically designed to supplement component shortage & along with few minor yet audible improvements.

About ODAC: ODAC is the DAC counterpart of the famous O2 amplifier, &  was released in 2012. The ODAC was jointly developed by NwAvGuy (The legendary engineer who created O2 amp) and Yoyodyne Consulting . Yoyodyne generated ODAC’s  circuit board, and NwAvGuy provided performance analysis. Yoyodyne has remained responsible for all production engineering & distribution. ODAC was certified as Objective by NwAvGuy; Yoyodyne generated the design and controls its manufacturing.
The new Rev.B uses SA9023 & PCM5102A, and the Low dropout regulator has been updated to a ceramic stable Analog Devices ADP151 equivalent part. Fixes include: Added 16x vias to USB support pads to improve mechanical strength of mini-USB jack, new improvised circuit board & locked EEPROM to prevent IC failures, fixed USB supply stability, & minor performance improvements.
Technical specifications of ODAC Rev. B:

Freq. Response 20Hz-20kHz          +/- 0.04dB

THD+N 100 hz -0.15 dBFS               0.0028%

THD+N 20 hz -0.15 dBFS                 0.0015%

THD+N 10 Khz -0.15 dBFS               0.0024%

IMD CCIF 19/20 Khz -6.03 dBFS      0.0015%

IMD SMPTE -6.03 dBFS                   0.0015%

Noise A-Weighted dBu 24/96           -103 dBu

Dynamic Range (A-Weighted)          > 112 dB

Linearity Error -90 dBFS 24/96         -0.08 dB

Crosstalk -10 dBFS 100K 3.5mm    -86.40 dB

USB Jitter Components 11025Hz    -112.3dB

Maximum Output Line Out 100K     2.1 VRMS
Audio Formats (Bit/Freq):    16/44, 16/48, 16/88.2, 16/96, 24/44, 24/48, 24/96

Native Driver OS Support:    Windows XP & Later, OS X x86, Linux
Distortion:  < 0.005%

Inputs: Mini-USB
Interface: USB, Audio Class 1

Output: 3.5mm (or RCA), line level

Power:    Self-powered by USB

Packaging & Accessories: The ODAC comes packed in JDS Labs stamped strong black cardboard box. It withstood a rough journey across the globe, yet remained in perfect shape. That explains everything.
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Included Accessories
Instructions: Contains instruction about operating the device & some warranty information.
USB Cable: Mini USB cable with ferrite bead, Monoprice brand, has very good quality with 28+1P/24+2C AWG gauge, matches very well with ODAC.

Design and Build:  It has an aluminium case, & the ODAC  Rev.B which Im reviewing is the RCA version (with RCA connection) The RCA version ODAC is a tad little longer than the regular ODAC with RCA jacks being connected to ODAC via soldered wires. This version also retains its regular 3.5mm jack. The Rev.B physically exactly same as the original ODAC, & has same dimensions. On one end we have both Mini USB connector & 3.5mm output. On the other end (for RCA versions) we have RCA output jacks.
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The DAC itself is very small, nimble & has small footprint. Can also be used as portable DAC, as it is self powered. It does not require any drivers & works on low current draw, which is a plus for compatibility with portable android smartphones. The Rev.B has the same (or even better) benchmark reliability, performance than the ODAC.
Points : 10 out of 10, Excellent, very practical, feasible & well implemented.

Sound: The ODAC Rev.B puts out a very impressive performance, especially its transparency & soundstage. It does not any particular coloration of its own. Soundstage is amazing. It has a fully circular 3D imaging. Detail retrieval, and dynamics are excellent. Overall the sonic presentation contains high level of transparency and accuracy. Absolutely zero audible hiss/noise, and zero EMI pickup.
Benchmark performance for the price. It has supreme value for money. In practical conditions, the performance of ODAC Rev.B is perhaps is beaten only by fancy multi-hundred dollar DAC. Amazing clarity & transparency, it completes the objective parameters set for an ideal DAC. Overall, ODAC Rev.B puts up a highly impressive performance. 
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Points: a full 10 out of 10, Simply amazing. Delivers beyond expectations.

Comparing ODAC with ODAC Revision B: Physically they are both having exactly same dimension. Just components & signal paths in some areas have been updated. Audibly, it is very hard to tell the difference between the two. But Rev.B definitely has slight audible edge over original ODAC. Practical differences are: ODAC Rev.B supports 88.2 KHZ & has higher 2.1VRMS output, SA9023 ensures better compatibility with android & I devices. Redesigned circuit means bullet-proof reliability. The 2.1 VRMS really helps, providing decisively better output. In case of O2 amp, Rev.B helps in more powerful driving of headphones & a lower gain of 1X/3.3X as optimum.
Frequency Response, 20-20kHz
+/-0.14 dB
+/-0.04 dB
THD+N 100 Hz, -0.15dBFS
THD+N 20 Hz -0.15dBFS
THD+N 10 kHz -0.15dBFS
Noise, A-Weighted
-102 dBu
– 103 dBu
Dynamic Range (A-Weighted)
> 111 dB
> 112 dB
Dynamic Range (Un-Weighted)
> 107 dB
> 109 dB
Crosstalk @ 1kHz, -10dBFS (3.5mm)
-80.4 dB
-86.4 dB
Sum of Jitter Components @ 11025 Hz, -1dBFS
-105.8 dB
-112.3 dB
IMD CCIF, -6.03 dBFS, 19/20kHz, 24/96k
IMD SMPTE -2 dBFS, 24/96k
Linearity @ -90dBFS
-0.09 dB
-0.08 dB
Maximum output
2.00 VRMS
2.10 VRMS
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Conclusion:  I consider ODAC Rev.B as an exception DAC, because in my experience I never came across a DAC as reliable, as functional, & as performing, yet affordable as it. The Rev.B continues the legacy & reputation of ODAC forward, with even better level of practicality. Overall it performs extremely well. Highly impressed. The ODAC Rev.B has a benchmark performance.  Objective: Completed
Overall, I can award a full 10/10 for ODAC Rev.B owing to its supreme performance in all aspects. My strong recommendation for all enthusiasts who want a truly objective performance.
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Which one do you think sounds better this Odac or the graham slee bitzie.


New Head-Fier
Pros: Excellent Sound Quality, Customer Service, Quick Shipping
Cons: None
Recently bought a HD650 and quickly realized my laptop wasn't good enough, bought this and it has IMMENSELY improved the sound of my new headphones. I am using this ODAC and a PA2V2, waiting for my Crack Bottlehead to ship. Should be a great setup once it's all done.
Shipping was excellent, even with a custom engraving I got it in three days.


New Head-Fier
Pros: Neutral. Silent(no EMI). Tight bass.
Cons: None.
I have so far had owned only FIIO products E10,E11,E17 etc. have tested out audioengine D1, matrix iDAC and some other DACs before purchasing this DAC. This is hands down best performer of all the products i have owned or tested so far. When you plug it in you'll definitely notice significant improvement in quality. Even by comparison of the other DACs and the way they improve overall SQ. None of them have given me this noticeable improvement over my  laptop's default Soundcard's output. It's not that E17 or Audioengine D1 didn't improve SQ, they in fact did (and not small by any means) but the jump is not quite as high as this little DAC. For the asking price i don't think one would ever find a product as good as this one. Bass sounds just so awesome like never before. It is tight and one can easily notice the improvement in the bass quality. Soundstage gets bigger and treble is accurate and when plugged in, my HD650 starts sounding a different headphone (the lush signature is still intact even if treble gets a bit more sparkle).  I am not much of into highs i like the way they are represented on HD650 without any Amp/Dac.But still treble sounds more accurate when plugged in with this DAC. Must say i am amazed with ODAC, 
Makiah S
Makiah S
Agree'd, I was suprised how much better everything I owned sounded after I got my oDac back in the day! 


100+ Head-Fier
Pros: Completely transparent
Cons: None
The ODAC was engineered with a mind for science. Using science the designer created a completely transparent source that has absolutely no effect on the music. Thus, you hear only your headphones/speakers/ect, not your source.
If you don't want to color your music, It simply can't get better than this. As long as you only need a RCA out or 3.5mm out, and want a transparent source, it cant get much better than this.
EDIT: Head-Fi's website will NOT update the "Detail" sliders and are fixed. Website is possibly broken
Which other transparent dacs have you compared it with ?
I'm not going to lie, I don't have the largest wallet on Head-fi.
With that said, I've been able to compare it to the Xonar Essence ST (which according to Asus is the "first precision clock tuning" DAC), and The Clip+, which has a great reputation on head-fi and has measured well by NwAvGuy.
To be honest I don't really ever plan to ever buy a DAC again to compare the ODAC too. The measurements of the ODAC speak for themselves.
+1 Here i really Enjoyed it too, and I really like the detail of the music with this Dac.


500+ Head-Fier
Pros: Small, USB powered, solid 2V output, noise-free, sounds clean.
Cons: No RCA (on my version), no Toslink/Coax.
Disclaimer: This review isn't based on NwAvguy words and/or the stereotypes arround the ODAC. You won't see me using the words "transparent" and or "clinical". I actually gave the thing an honest listen, compared it with what I had arround me and this is the review I came up with.
Now, you might ask me, why did you buy the ODAC? Well, I wanted something small that I could strap under my computer desk and forget there. That's it.

But how does it sound?

Silent. This thing is completely silent. When I sit next to it in a quiet room, It doesn't talk or scream to me, which is nice. Ok now kidding aside, where as my E10 was picking up EMI that I could hear easily on louder than normal listeneing levels, now I can max out the volume and I can't hear a thing (with no music on obviously or my ears would be bleeding), which is really good in my book. Now, how does it sound with music on? First thing that striked me: the details. Bad recordings now sound terrible and good recordings sound terrific. I'm not talking about 24/96 "post-modern alternative on the verge fusion" jazz here, but well recorded 16/44 albums from Supertramp, Mumford and Sons, Muse, Jason Mraz, Maroon 5, Pink Floyd, Radiohead and so on. The sound is well laid-out and no part of the frequency spectrum jump at your face. I like that.

Now for a little comparison. My dad has a Bifrost on his fulls-size speaker system, so I replaced it with the ODAC to see if it feels any different, I asked him. We listened to Jazz at the Pawnshop songs where we can hear people moving their glass of whatever they are drinking arround and talking in the background. Our conclusion? He and I can't tell apart each DAC.  Both sound really good, and that's all what really matter. Now, please don't ask about our methodology or whatever. This wasn't a scientific test and we didn't have any expectatrion or preconceived idea of the results. We just gave an honest listen and WE just couldn't tell the difference really on our setup. It might be worth nothing to you, and that's cool, but there you go.

Conclusion? For 150$, you get really great sound from a simple USB port. If you want more inputs and flexibility, look elsewhere.

Gear used: Odac, Bifrost, Valhalla, HD650, Grado SR80, dad's speaker setup.

Nice, many reviews said that ODACs are really great and can compare to some other expensive DAC in sub $400 category. I read few comments and the owners said Bifrosts are just better than ODACs a little bit.
My combo is ODAC-> C421 OPA 2227 and HD598 but somehow it makes me feel tied for long times listening or maybe I do not like HD598. Maybe I will try other headphones. It is time to buy a new pair of headphone but the problem is money ha ha ha.
Thanks for the review.
Thanks for the review....I compared to several dacs costing alot more and could not honestly tell any difference....the ODAC is well designed and works well....does exactly what its designed to do perfectly.
Thanks for the review man. I just got mine, it certainly is better than my built-in soundcard. I agree, if you want more or specific I/O's this is not the DAC.


Headphoneus Supremus
Pros: not excessively revealing, smooth treble
Cons: it's not huge and doesn't weigh 100lbs. it's too small. Can't possibly sound good being so small.
I had a heck of a time getting this to sound right. It made me aware of nearly THREE problems with my setup. Not even kidding. My desktop computer's rear USB port does not work with this. A powered USB hub is required. Next for some strange reason I have to use high gain on my Q701 with this dac and my Headroom Micro Amp. With 8% volume. If not, the Q701 is too fatiguing. This never occurred with my HRT MSII. On that, Medium was fine.
I'll keep this short (EDIT: whoops guess not). First impressions of this over my HRT MSII is that it sounds much more balanced. Yet strangely any of my garbage tracks suddenly don't sound so bad. It seems to take the edge off them. Why? I have no idea. On 5 of my CD players these same tracks are just awful and much worse. Way more fatiguing. I'm listening to a song right now that was unbearably bad on my HRT MSII and CD players and now it's quite listenable...even on the Q701. You could say those 5 players are just more revealing or colored, but that's unlikely to be true.
The idea that this makes the Q701 sound less warm or more revealing or analytical is nonsense. With my Q701 I still retained it's warm and full sound. If anything, it's treble is even more smooth and easier on the ears. The Q701 now sounds closer to neutral than before. I would say in comparison the HRT was a tad warmer, but only slightly. Again, it doesn't make the Q701 any leaner in the mids or anything like that. This is really the best i've ever heard the Q701.
I find the ODAC gave the Q701 a slightly larger soundstage with better imaging, but the difference isn't huge. I was actually confused with the difference in imaging. My X-Fi Go Pro does seem to give the Q701 a slightly larger soundstage than the ODAC. Don't really care though.
I actually find this DAC very musical and smooth sounding. Maybe it's the headphones and music too. All my garbage tracks are not put under the microscope at all. They sounded much worse on the HRT MSII. I actually think that thing might be more revealing of bad recordings.
I've not had this thing magically change any of my headphones in major ways. Generally they sound just like they should, but even better in many areas.
The biggest improvement in sound was with my $80 Koss Pro DJ100. Mostly improved soundstage size and better bass. Not more bass, but just better bass. I didn't even think that was possible since i've never heard the bass as good on any other DAC. I did experience a bit more detail with the DJ100, but I didn't feel ever that anything was being shoved in my face.
One reason I sold my HRT MSII is that I didn't like it with my HD-598 and HD-580. I just have weird preferences I guess. At first I blamed my amp, but i've found it's more transparent than I had originally thought. Less colored than the HRT MSII (which is still fairly neutral). The ODAC is really so much better IMO with my two Sennheiser headphones. It doesn't make them warmer or give them any extra bass. I think if I ever tried the HD-650 again, this is the DAC which would make me like it even more.
BTW it's general "signature" is close to my onboard sound, Sansa Clip+ and X-Fi Go Pro DAC. Obviously this is a huge upgrade, but all of them sound pretty flat to me. Blind A/B test would be stupid easy though.
I could never ever hear a difference in DIY (cheap) cables until I got my HRT MSII. It was stupid easy to tell the difference (less so with interconnect cables). Nothing major. With this I can't hear an ounce of difference. Only if the cable is a very high capacitance wire (such as Canare). My guess is that the ODAC is just no super duper revealing detail monster like the HRT. No idea here. I'm perfectly happy with my $1 Monoprice cables. Consider this a bonus. I can't really figure this one out (for myself).
Now that i've found a budget amp that plays well with EVERY headphone i've ever tried, I think i've finally found the DAC to go with it. I don't know why, but every single popular amp or DAC on Head-Fi i've tried has had some weird coloration to it or only sounds best with specific headphones. I hate that. Maybe I just have very bad luck. I'd also prefer to not feel the need to buy a DAC/amp every year and would rather spend that on headphones or new music.
BTW I think maybe this has very slightly rolled off highs. Probably not, but I guess it's possible. Not like the E10 though...this seems far more balanced than the E10. E10 didn't sound neutral, yet measures flat. Strange.
10/17/12 UPDATE:
I've now been using this since 8/20. Never imagined it'd be such a nice upgrade from my HRT MSII, but it is. Unlike the HRT, this thing (like my amp) plays well with every headphone. Sounds equally good with every single thing.
Lately I did notice that it's even less warm sounding than my Clip+. I took my KRK KNS-8400 downstairs to my main setup and it just wasn't the same, but still good. Yeah..I just called the Clip+ warm sounding!
I'd say my favorite headphone with the ODAC is the Q701.
For the record, I still don't find the ODAC excessively detailed or too analytical. Detail level is just where it should be. The HRT did seem to be more detailed. Why? Not sure. Maybe it's just due to a little more coloration and my brain being fooled. Who knows..
With this ODAC, my Q701 sounds as smooth as the HD-598. Nothing in it's frequency jumping out at me too much. Not thin or analytical, but quite musical.
Thanks for that last post. I've also been convinced the only difference in how cables "sound" is due to capacitance too. I usually tend to avoid anything that's very high capacitance with warmer sounding headphones. Maybe this is why people love silver on the HD-650? It's probably ultra low capacitance. It's nice not having to bother with fancy cables on my ODAC. Not that I would..DIY ones are sometimes worthwhile. Of course i'm only talking about headphones cables and interconnects (not USB ones!).
I saw a PS1 with RCA jacks at my local goodwill, while scrounging for cheap-as-possible headphones to smash for an art project. Looked at the serial, it was the SCPH-1001 I'd read Art Dudley (I think) from Stereophile write about. I was curious...... but honestly, I only have about 10 CDs, mostly I have 256-bit AAC files (and videogames) and only buy CDs of my favourite albums. Since buying the Q701, this may change... though what I REALLY want with enough budget is a nice Vynl system. Meanwhile, the ODAC might be more wallet-friendly.
So many impossible imaginary differences, impressive.