JDS Labs O2+ODAC

Before starting this review, I would like to share the technical aspects and package details.

Also, I am so thankful to Jude from JDS Labs for giving me this opportunity.



Objective 2

Frequency Response +/-0.1 dB (20Hz-20kHz)
THD 1 Khz 150 Ohms 0.0016%
IMD CCIF 15 Ohms 0.001%
IMD SMPTE 0.002%
Noise (ref 400 mV) -105 dB
Max Output (33 Ohms) 613 mW
Max Output (150 Ohms) 355 mW
Max Output (600 Ohms) 88 mW
Output Impedance 0.54 ohms
Crosstalk (15 ohms) -65 dB
Channel Balance (50% volume) 0.6 dB
Battery Run Time 6-8 Hours



Package Contents
Objective2 Headphone Amplifier

15VAC Power Adapter

2x Tenergy 9V NiMH, Low-Self-Discharge Batteries

Rubber Feet



OL DAC

Frequency Response 10Hz-20kHz+/- 0.15dB
THD+N 20Hz-20kHz< 0.001%
IMD CCIF 19/20 kHz -6.03 dBFS0.00033%
IMD SMPTE -6.03 dBFS0.00031%
Noise (A-Weighted)-109 dBu
Dynamic Range (A-Weighted)114 dB
Linearity Error -90 dBFS+/-0.01 dB
Crosstalk -10 dBFS 100K RCA-108 dB
USB Jitter Components 11025Hz-116 dB
PCB Stackup4 Layers
Maximum DAC Line-Output, 100K2.00 VRMS



Package Contents

OL DAC v1.10

15VAC Power Adapter

3ft USB Type-A Cable



Design:

Surprisingly, JDS Labs devices are designing and producing in USA. I think that JDS Labs can request higher prices easily with regard to audiophile product prices in the market recently.

Objective O2 and OL DAC is quite portable for desktop usage in terms of its size. O2’s capable of being used on-the-go but not as good as like Hugo or Mojo. Both O2 and OL-DAC are same size. Their height and width measures are small and it only needs a tiny space. Both devices are made of high quality aluminium material, finish points are clean and smooth, material and workmanship quality are extremely successful and durable.

Both devices require A/C adaptor however you can use O2 with battery. Portability is not so necessary even but, in some cases, it is quite useful. Battery life is somewhere between 6 hours to over 8 hours but it depending on use. Volume knob is very soft and can be adjusted easily, it does not feel cheap and cheesy; in that kind of amp’s, volume knobs might be unbalanced and slack. You do not hear hiss while adjusting volume knob. Almost all of the functions and outputs are integrated onto to front panel which I found very practical. I really like O2 and OL-DAC in terms of design, workmanship and material quality in the overall.



Output Power:

O2’s is powerful than it is expected. Probably, it is strong enough to drive almost all the headphones with authority in the market. O2 is very suitable for IEM which I really like its harmony with the IEMs I have. I also would like to indicate that I did not hear any disturbing hiss with low impedance IEMs. Andromeda is very sensitive earphone and I didn’t hear any disturbing background noise. I listened O2 with all IEMs volume knob 4e 1 ratio. I also would like to remind that O2 is so powerful for IEMs and it is better to control your previous sound level for your earphones and ear health before listening it with IEMs.



Sound Type:

I absolutely like the sound quality. O2’s sound character is quite transparent and clean, contrary to my expectation. General presentation of O2 is very neutral and it doesn’t bring anything in front. It presents the sound naturally without colorizing and its relatively light and bright tone. Both bass, midrange and treble were exceptionally fast and sharp. Overall instruments tune is neither thick nor thin, it is in between. It is able to stay partly musical without being boring. There is balance from lower to upper frequencies in overall presentation and none of the frequencies are overlapping. High-resolution files sounded very fine with 24-bit, AIFF, WAV and DSD audio.

It is fretless in overall and it is providing a clean, smooth listening. In this price range, many of the earphones feature the warm musicality instead of delivering technical performance due to the high cost and workmanship of detailed technically successful products. However, O2 surprises me by delivering technically good performance because I used to see this performance in a higher price range. I believe that O2’s and ODAC’s performance is above it price and I have to admit, it’s pretty impressive at this price range.



Trebles:

I felt the treble to be well tamed with good extension and it also has a very detailed and naturally textured extension. Trebles are really significant in the overall presentation and they are not sharp. It is very well extended without being sharp or unnatural. Upper frequency presentation is extended, effortless and pretty clean. You do not face any aggressiveness while listening to music. I listened to almost all the treble-dominant IEMs but I did not run across to any diffused or uncontrolled trebles. I really liked these controlled trebles that know where to stop. The detail level is above this price range. It is very successful in terms of instruments distinction and positioning. I can easily define the cymbals’ position in Rock based tracks, cymbals are not unnatural generally. It’s also effortless, so It is not tiring the ears while listening and not getting out of the hand while giving the detail. It is great that it can play in detail without causeing tiring trebles.

Mids:

Mids are neither front nor behind in the overall presentation, same as the other frequencies. Their quantity is almost same as the trebles and their character is not disturbing. There is no sharp or bright presentation, the character of the mods is linear accompanying to the overall presentation. Bass frequencies do not crush the mids and there is no mid hump in low mids. Instruments plays organic and realistic. Mid presentation is spacious and detailed in general. Vocals are enough detailed and impressive for many listeners, they are centrally located in the overall presentation. You can hear the vocals very clear and bouncy. Vocals and instruments have good and natural textures that make the music enjoyable and musical. It is very easy to understand that there is no veil and it is very close to the realistic tones of instruments. Mids are very easy to listen it and it offers a joyous listening for hours without boredom.





Bass:

Low end is clean and detailed. The quantity of lower frequencies is quite satisfying, it is not too much, it is detailed and controlled. Bass quantity varies from earphone to earphone but its overall bass quantity and tones are slightly more than neutral, so the bass quantity is enough for many users. Sub-bass is there, but it is rolled off and laid back little bit but somehow sub-frequency is fair enough, relatively the presentation is soft and easy. I really like sub frequencies because the quantity is not more than necessary. General presentation is controlled and do not spread. There is no bloat or overhang and It has good timbre and presence. Punch and speed of the bass is fairly enough. Bass does not loose its control and it’s fast in tracks, so it does not tire the ears in this term.



Soundstage:

The soundstage is spacious with an excellent layering and precision. Stage is transversely wide located however the depth is relatively good. It spreads the instruments into a spacious and wide area, there is enough distinction space for the instruments. The layering is very well done with a lot of air between them and every instrument. It does not feel like the soundstage is virtually increased. Background is quite silent and instrument distinction is successful. There are not any issues like mixing all instruments. I also found the background of device really clean.





Verdict:

The O2 and OL DAC combo is an exact price/performance combo in terms of size, sustaining IEMs and over the headphones and being a good desktop alternative. They produces a great deal of clean detailed sound and power from a compact size. Also, it feels solid and aesthetically is top notch at this price. Another reason why I like this combination because the presentation is slightly musical and technically good. I think the harmony will be good with most of the headphones and the main reason of it is the balanced sound frequencies. Would I recommend this combo? definitely yes! I can easily recommend this combo to every audiophile and have no doubt this is a fantastic-sounding dac-amp combo compared to other products of the same form factor at this price range.

I look forward to seeing many products in the JDS Labs for years to come.

This is a review of the JDS Ojective2+ODAC Rev B amplifier and DAC combination.
 

 

The JDS Ojective2+ODAC Rev B (O2/ODAC) was sent to me for free by JDS Labs for the purpose of doing this review and including it in my recently started $250+ amp/DAC comparison thread. A big THANK YOU to JDS Labs and Jude for letting me check it out.
 
The JDS O2/ODAC is available from the JDS Labs homepage and the price at the time of this review was $279 in the default configuration (more about customized options and prices later).
 
https://www.jdslabs.com/products/48/objective2-odac-combo-revb/
 
I’m not in any way affiliated with JDS Labs.
 
Short introduction to JDS Labs:
JDS Labs makes high quality DAC’s, headphone amplifiers and cables. They are based in Collinsville, Illinois, USA.
 
This is what they say about themselves on their website:
“We go above and beyond American manufacturing. We built our in-house machine shop and production line to achieve product quality that we're proud of. JDS Labs's success comes from our obsession with brilliant audio engineering. Performance of our amplifiers and DACs pushes the market forward.
 
During product development, we utilize a PrismSound dScope Series III audio analyzer to conduct professional sound quality benchmarks. An audio analyzer is capable of generating reference quality audio signals and measuring the resulting output of an audio device under test. This allows us to perform impulse response tests, fast-Fourier transforms (FFTs), and continuous-time analysis in order to observe specifications which directly impact audio quality. In simplest terms, an audio analyzer generates exceptional audio signals and checks to see how closely a tested device compares to its own quality.”
 
About me:
 
Built, accessories and functionality:
The JDS Ojective2+ODAC Rev B are a solid state headphone amplifier, DAC and pre-amplifier (optional) combo.
 
In my opinion the O2/DAC is already a classic piece of equipment in the headphone related world in the same way as the Beyer DT 7/8/9XX, AKG K/Q7XX or Sennheiser HD6X0. They’re all known for offering excellent performance for money. The O2/ODAC is an open source design so anyone with some soldering skills could build one but there are also a number of half-baked sets and also fully finished options like the one JDS Labs are selling. I’ve read a lot about the O2, ODAC and O2+ODAC for several years now so naturally I was super happy to finally be able to hear it for myself.
 
The O2/ODAC is available in two different colors: black and silver. I’ve got the black version. It’s also customized to some extent and you can choose to power jack in the back (+3$) instead if in the front, a 6.3 mm headphone output instead of the 3.5 mm one (+$30) and/or you can chose to add a dedicated DAC output as either 3.5 mm (+$3) or 6.3 mm (+$17) jack.
 
The rated output power of the O2/ODAC is 613mW at 33Ohms.
 
The JDS Ojective2+ODAC Rev B have a metal/aluminum chassis that feels really solid. The physical controls available on it do also feel very reliable. The physical controls sums up to a volume knob, a switch to choose between how or low gain and an On/Off switch.
 
The JDS O2/ODAC offers one USB mini digital audio input and one separate AC power input.  It also offers an analog 3.5 mm audio input and, as already mentioned, for a few dollars extra you can also add a DAC output in the back. There’s also a headphone out socket.
 
Unfortunately I’ve not been able to make the O2/ODAC to work with any of my Android devices. My guess is that the USB driver is too old to be prepared for this.
 
The O2/DAC support all popular file formats for audio up to 24bit/96kHz files. The lack of support for higher sampling rates as well as the lack of support for DSD files are probably signs of the design of the O2/DAC being several years old by now.
 
The accessories included are:
1 USB cable (USB A to B Type, 1.5M)
1 User's Manual
4 rubber feets
1 Power adaptor (AC 15V)
 

 
The specs:
The O2/ODAC has been with me for alomst two months now and it has played well over 50 hours. 
 
Demolist:
 
Sound impression:
The first thing that I noticed when I started to listen to the JDS Ojective2+ODAC Rev B was that it was less analytical and fuller sounding compared to what I was expecting.  
 
This review will mostly be about the O2/ODAC as a DAC/amp combo but before I start on that I’d like to make a very short comment about the O2/ODAC as an amplifier only. As far as I know the original design for the O2 was for a headphone amplifier only and the goal for it was to have a completely transparent and neutral presentation. When I hooked up the bit Opus #1 DAP to the 3.5 mm analog input on the O2/ODAC the sound is indeed pretty much unaltered in comparison to listening straight from the #1. This is quite impressive and exactly what a well deigned amplifier should do. This leads me to believe that the “signature” I hear from the O2/ODAC is actually that of the DAC section. So let’s continue to explore how it performs as a DAC/amp combo.
 
Bass extension and impact is very good without any noticeable roll off in the lower frequencies. Sub bass and mid bass interact seamlessly with equally good quality and similar quantity making the whole lower frequencies very fluent. The combination of great bass quality and a natural quantity makes the presentation dynamic and very easy to like.
 
The midrange is liquid and smooth with plenty of details. The O2/ODAC sounds very linear through all frequencies and the midrange is no exception. Nothing really stands out and it sounds very natural and dynamic. I feel as if there’s some air missing from the sound though making the overall presentation a bit on the intimate and even closed in side. The sound is natural sounding and I do find that vocals is very well reproduced with enough wright on male ones and no fatigue with female ones.
 
The treble is well extended but does lack some air and I’m not able to detect any harshness whatsoever in it. Being slightly on the warm side it does never feel harsh or artificial to me but rather full and natural.
 
The overall presentation has good soundstage but better depth than width and height.  Layering is also good but I do sense some lack of air between the instruments. The background does feel black and calm but the overall presentation is still a bit on the intimate and closed in side. Transparency is also quite good and all together I’d describe the sound of the O2/ODAC as slightly warm with great dynamics. This is a signature that I personally find to be quite enjoyable paired with most IEM’s and headphones.
 
Comparison:
Please note that the comments in the comparison section are not in absolute terms but in comparison between subject A and B. This means (as an example) that if subject A is found to be brighter than subject B it does not necessarily mean that subject A is bright sounding in absolute terms. I hope this makes sense.
 
In these comparisons I’ve been listening through my Hifiman HE400i’s.
 
I’ve been using the USB input when doing these comparisons. Both units has been hooked up to two different laptops both running Windows 7 with the same settings and I use MediaMonkey as my player of choice.
 
Both units was connected to a simple switch box through their respectively headphone outputs. This way it’s very easy to switch between the sources in minimal time. I also use a simple Android app to volume match the amplifiers so although maybe not perfectly scientifically the result should still be pretty correct.
 
Burson Audio Conductor V2+ (1,499) vs JDS Labs Objective2+ODAC Rev B:
Compared to the V2+ the O2/ODAC is more closed in and intimate sounding while the V2+ is more much more airy and has better timbre to the notes. The O2/ODAC is overall darker and also a bit duller in its presentation.  The V2+ has a larger soundstage width and an overall more relaxed and effortless presentation.
 
The V2+ of course has some other advantages as well such as significantly higher power output (4W @32Ohms compared to ca 613mW@33Ohm on the O2/ODAC), two analogue RCA inputs and both pre-amp and DAC direct RCA outputs, in addition it also has a great quality remote control.
 
Although both these are well build the V2+ definitely has a better build quality and should also have so costing about five times the price of the O2/ODAC.
 
Cambridge Audio DacMagic Plus ($499) vs JDS Labs Objective2+ODAC Rev B:
Compared to the DacMagic Plus the O2/ODAC has an overall sligh fuller sound. The ODAC offer more energy and attack while the DacMagic Plus, albeit being a touch brighter, is more relaxed and laid back.  The ODAC is more distinct in what it does and has better clarity while the Cambridge is smoother and had noticeable more air between instruments, this is also the reason that it feels more relaxed in my opinion.
 
Feature wise the DacMagic Plus offers both coaxial and optical inputs in addition to an optical output. The ODAC has a 3.5 mm analog input while the DacMagic has both RCA and balanced outputs. The O2/ODAC is considerable smaller and both units feel very well built. 
 
iBasso D14 “Bushmaster” ($249) vs JDS Labs Objective2+ODAC Rev B:
Compared to the O2/ODAC the D14 have a lighter and less dynamic presentation. The D14 is definitely the brighter sounding of the two while the O2/ODAC is warmer and more dynamic but also more congested. The O2/ODAC does also offer more energy and attack. The treble on the D14 is more airy and has better extension. Overall the iBasso unit is cleaner and leaner with a wider soundstage while O2/ODAC is more dynamic and warmer sounding.
 
Feature wise the D14 offers both optical and coaxial inputs. They both have 3.5 mm analog inputs but and gain switch. They both have USB mini inputs and 3.5 mm headphone outputs (the O2/ODAC can be customized to 6.3 mm if wanted). The D14 can also run directly from USB power as well as on battery which makes it more flexible. The footprint of the D14 is quite a bit smaller. Build quality feels very solid while the O2/ODAC packs a bit more power.
 

 

 
For even further comparisons feel free to visit this thread for breakdown between more $250+ amp/DAC units (this is a work in progress and several other units will follow in the near future).
 
http://www.head-fi.org/t/816410/peter123s-250-amp-dac-combo-comparison-thread#post_12771442
 
Matching:
The output impedance of the headphone output on the O2/ODAC is rated to a very low 0.54Ohm. This means that it should work really well with pretty much every pair of headphones and IEM’s out there.
 
In this section I’ve tested how some of my favorite headphones but also one earbud and one pair of IEM’s pairs up with the O2/ODAC.
 
Hifiman HE400i ($449):
The HE400i, when paired with the O2/ODAC, has great drive and dynamics making it sound quite engaging to me. The HE400i doesn’t have the widest stage and neither does the O2/ODAC but they still work very well together making for a non-fatiguing and toe tapping listening experience.
 
AKG Q701 ($300):
The Q’s sound good paired with the O2/ODAC in my opinion. The bass has good presence and impact, which indicates that the power is sufficient. I find the overall sound slightly on the warm side and this suit the Q’s quite good. Although this combination doesn’t sound bad I’ve heard better sources for the Q’s.
 
Philips Fidelio X2 ($300):
The X2’s has plenty of dynamics on its own and can sound a bit too bassy and boomy when paired to a warm source that have more than the natural bass presence. With the O2/ODAC it sounds full and engaging, retaining its great dynamics without getting overly boomy. This pairing is very good in my opinion.
 
VE Zen 2.0 ($138):
The Zen 2.0 is a 300Ohm earbud that I like a lot and tend to use instead of closed headphones.
 
The Zen 2.0 has a smooth and pretty laid back signature that works fine well with the O2/ODAC. There’s enough energy and dynamics to make the presentation engaging and easily enjoyable. I’d say that this is a very nice combination.
 
Aurisonics ASG-1PLUS ($500):
The ASG-1PLUS is an 11Ohm hybrid IEM (1 DD + 1 BA).
 
The 1PLUS has an excellent out of head presentation and its bass (especially mid- and upper bass) is quite a bit subdued.  I’d say that they work fine with the O2/ODAC. There’s enough dynamics to be enjoyable will all kinds of music but the overall presentation get a bit on the dull side. This is still an enjoyable combination though. Although the 1PLUS is not as easy to drive that the 11Ohm suggest I’m not able to detect any background hiss whatsoever when using them with the O2/ODAC.
 
To sum up the matching section the signature of the O2/ODAC does make pretty most of my headphones and IEM’s sound very good and I haven’t come across anything that pairs badly with it.  The O2/ODAC has a very low amount of audible hiss even when paired to my most sensitive IEM’s. The O2/ODAC does also have enough power for all my full sized headphones which makes it very versatile in practical use.
 
Summary:
The JDS Ojective2+ODAC Rev B may be a bit old in its design and not offering support for the latest and greatest high definition audio formats but in my opinion it still holds its own even in today’s crowded market.  It offers USB audio in as well as an analog input and is also partially customizable upon ordering. I’d also like to add that while the O2/ODAC is a good amp/DAC combination, although it may lose out in overall performance against more expensive offerings, it is an amazing amplifier delivering a truly neutral presentation just the way a great amplifier should. So if you’ve got a great quality source already the pure amplifier version of the O2 may be a better, and cheaper ($129), option.
 
Priced at around $300 (depending on configuration) the JDS Ojective2+ODAC Rev B may not punch way above its price point anymore but I’d still consider it a valid option within its price bracket. It doesn’t support DXD/DSD but if that’s not a big deal to you and you value a fairly neutral and very natural sound I’d still recommend looking at this classic piece of equipment if you’re on the hunt for a new partner for your computer or laptop.
 
Audio Quality: 4
Design: 4
Quality: 4
Value: 4
Features: 4
 

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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 also have their own products: C5/D Portable amplifier/DAC, Element desktop Amp/Dac along with their Cmoy BB amp. My profound thanks to Mr.John for arranging a sample unit for my evaluation.
 
JDS Labs O2 was my first ever 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 in my ears.
 
About O2/ODAC:  The Objective2 as we all know, is a very famous beginner level amplifier, has a very neutral sound signature. Few years ago there were not many amps available under a budget. The one’s available didn’t perform good. O2 was designed by a U.S electric engineer “NwAVGuy” in 2010-2011. The O2 amp standalone is portable & battery operated. But take out the battery & you can fit a tiny DAC inslide the same enclosure called ‘ODAC’.
 
ODAC is the DAC counterpart of the famous O2 amplifier, & was released in 2012. The ODAC was jointly developed by NwAvGuy 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. Rev.B now puts out 2.1VRMS power.

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Packaging & Accessories: The unit 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. Included accessories:
 
Power Adapter:  15V AC-AC adapter. The AC-AC adapters help in minimizing flux leakage in the circuit.
 
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.
 

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Design and Build:  It has an aluminium case, & the unit which I am reviewing is the RCA version (with RCA connection for ODAC) The RCA jacks being connected to ODAC via soldered wires.  The device 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. Another advantage of O2/ODAC is, you can build one right in your home using basic soldering tools. It's DIY Friendly.
 

 

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Sound: Both O2 & ODAC are well documented with scientific proofs about the accuracy of sound delivery, so no questions about that. It delivers whatever is fed into it’s system. Using neutral headphones like HD800 or K702 makes the experience bitter due to harsher treble, but with darker sounding headphones like LCD-2, O2/ODAC does a good job. Driving power is fine, though not as powerful as desktop amplifiers. Op-amps can be swapped for a different hearing experience. Take out the 2068D & install a compatible op-amp of your  choice.
 

 

 
Comparison:  I would like to compare the O2/ODAC with Schiit Magni2/Modi2 which costs under 200$. Schiit has improved the original Magni & Modi, now the reliability & sound quality is noticeably better than the original version. Both Magni2 & Modi2 outperform their counterparts O2 & ODAC Rev.B respectively. Modi2 is much more accurate than ODAC plus an added advantage of 24/192 capacity. Modi2 also sounds much cleaner, clearer than ODAC. Magni2 is more powerful than O2 and also delivers higher transparency. As combo, Magni2/Modi2 outperforms O2/ODAC. Schiit combo costs 200$ with additional features & better sound quality, hence Its a value for money deal.
 

 
Affordability:  The truth is, O2/ODAC is losing its charm it had few years ago. This is due to tough competition from modern & advanced products with latest designs. Had been NwAVGuy still around, he would have definitely continued developing the O2/ODAC . But sadly he has disappeared from audio community since long back. So I have to conclude that O2/ODAC is now outdated, and as a replacement, Schiit stack serves the purpose under 200$ budget. The O2/ODAC costs about 275$, which is significantly higher than the Schiit combo.

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Conclusion:  O2/ODAC though once a benchmark for performance, is outdated. But it still delivers what it was designed for: “Objective Approach with no BS”. O2 & ODAC created tough competition & compelled audio companies to develop affordable devices with much more value to customer’s money. O2/ODAC will slowly fade away, but will always be remembered as the Game Changer.
 
My tribute to NwAvGuy: The Man behind the Change.
 

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