This is a benchmark headphone amplifier for many,including Earmass. I have been reviewed few of the headphone before with the Objective 2 amp,well,it is not the JDS Labs version anyway,it is just a local DIYer build version.
I have detected different performance from both of the O2 amp anyway. When I first got my Objective 2 headphone amplifier from a local DIYer,I was just feeling that every reviewers just exaggerated on the performance of the Objective 2 amp(As the DIYer declared that it is same performance as O2 amp should),I am really getting upset and disappointed with I got from the amp,but that is until I get this review set,I was just saying ‘SHIT! This is not the O2 like that O2!’,funny but it is true,the JDS Labs Objective 2 amp is a true O2 amp that deserved the ‘Objective 2′ naming.
But this review entry is nothing related to compare the Local Objective 2 with the proper build like JDS Labs Objective 2 amp,I will just focused on the review of JDS Labs Objective 2 headphone amplifier.
Before we start, I would like to say thanks to John from JDS Labs to send me this review unit all the way from USA to Malaysia.
Description and Specification
There is actually tonnes of review on Objective 2 amplifier. Basically it is build based on the NwAvGu’s recipe. All of the details and information you are able to get from the ‘official’ website of it. This is a ‘transportable’ amp,as its size is far larger than portable amp should be(Such as the Govibe Minibox),but it has built in battery which can last quite long.
Below is specification that I directly copied from JDS Labs official Web:
- Frequency Response: +0.01, -0.01 dB (20Hz-20kHz)
- Gain: 2.5x and 6.5x
- Output Impedance: 0.5 ohm
- Volume Potentiometer Taper: 15A or 3B
- Case Dimensions: 108.50 x 80.00 29.50 x mm (excludes knobs/buttons)
- Weight: 11 oz, with batteries
Objective 2 is an amplifier that can be used as benchmark and has excellent score in the measurement. Some may argued that the attitude of the creator (NwAvGuy),but personally,I do think that he is quite brilliant with this creation.
Design and Build Quality

Front Panel. From left to right there is a 14-20 VAC(Make sure your adapter is 14-20 AC output),on/off button,3.5mm headphone jack,Power LED indicator,Volume knob,low/high gain button(1x or 6.5x),and a 3.5mm input jack.
I think the black colour one will be much better looking than the one I get,which is in silver metal colour. Anyway, silver looks charm as well. It is a straight forward amplifier,and the control and jack are all in the front panel. It is easy to use and really straight forward.
Packaging and Accessories
JDS LAbs will sent you the amp in a bubble wrap envelope and all you will get is the amp itself,few sheets,and nothing..Yes,nothing more. You have to purchase your own adapter that power up the amp. Me myself had scratched my head badly to find the dedicated adapter,it need a weird adapter so please make sure you have READ the instruction before buying the adapter,you need an Ac-Ac adapter,not the normal Ac-Dc adapter.
Working Method and Pairing/Power

Connect your source with O2 through a 3.5mm cable,then plug in your earphone/headphone. JDS Labs Objective 2 can work without the power jack plugged in as well. It has internam battery.
It works easily. First of all,make sure that youhave a DAC (Mobile phones,portable players and computer sound card is ‘DAC’ as well),connect it through a 3.5mm cable,then switched on the adapter(which is not included in the packaging),turn on the amp and volume,play your music through earphone/headphone (You have to plug in your headphone/earphone to the jack as well =P)
Seriously,Objective 2 had paired nicely with the earphone/headphone I throw at it,it is a neutral sounding headphone amplifier,no really any ‘coloration’ so it is easy to pair with. But I have detected that better not to pair any of ‘thin sounding’ earphone /headphone to O2,it has some kind of thin sound itself as well.
Power wise,it is quite powerful especially for the small and slim size. It can power up all of the tested earphone/headphone with just 9 O’clock in low gain mode.
Sound
JDS Labs have been paired with Stoner Audio UD100 through Black Octagon Bos2 3.5mm male to male cable, tested with Creative Aurvana Live!,Shure Se425,Bowers and Wilkins P3,RHA MA350,NuForce Ne700,Yamaha Eph-100 and Soundmagic E10,songs play through Foobar 2000.
Objective 2 measured really well on measurement,so how do it sound?
High : It is good and extensive.
Mids : I think that it is a bit(Just a bit) thin,but it is still great.
Low : Punchy and deep,but lack the fun and impact that some including me would like.
Sound Signature : For me objective 2 is all about ‘neutrality’ and ‘transparency’. It is neutral and transparent,I have heard more expensive headphone amplifier,but none of them have the transparency and neutrality that JDS Labs Objective 2 provided. It is really transparent and has dark background,all along with superb clarity. Detail level is good as well. Nothing short,considered its price.
Sound Stage : It is open,spacious and has good sound stage. It has wide and deep soundstage,with good imaging as well.

‘Transportable’ amp VS Desktop amp,O2 is still small and really capable for its size. Bottom is Musical Fidelity Vcan II.
All Tested albums and Tracks are in Lossless formats unless otherwise stated.
Arioso – Daniel Domb and Carey Domb (Apollo)
When I first played this track with my Creative Aurvana Live!(CAL!),I am actually impressed,Wow,I have never heard soundstage this wide from my CAL!. Soon,I plug in my Shure Se425,and the violin and the guitar sound nice!
Black or White – Michael Jackson (The Ultimate Collection)
Electric guitar,checked. Bass line,checked. Vocal,checked. All with good clarity and accurate rhythm response.
When you Believe – Mariah Carey and Whitney Houston
I believe this song can be done with more expressive. The vocal is nice,but can be nicer,lack the texture that I will like. But is still enjoyable.
恰是你的温柔 – 徐雯
徐雯has the sweet voice that I love. This song play with good clarity but I personally think that vocal can be more expressive,it is just when I am asking for more.
Diamonds – Rihanna (Unapologetic)
Vocal is good so the bass. The bass is hitting quite hard and punchy,but lack the impact and ultimate body.
Conclusion
Good : Neutral and transparent (Hard to beat), Superb Clarity, Good Detail Level, Soundstage, Audio Quality (No significant flaw), Can be powered up by internal 9v battery, Good looking,Price,Small,Easy to pair with.
Bad : No Bass Boost means No Fun, Low frequency is not really satisfying if you need something that has big impact,No indicator for battery and charging indicator.
I have a lot to love in Jds Labs Objective 2 amplifier. In fact,Objective 2 will become my benchmark amplifier for the review,as it has minimal coloration and excellent neutrality, so it will be great for my review job. It is a good headphone amplifier I can say.
However,I love JDS Labs CmoyBB V2.03 more. Well,I understand and totally agreed with you,Objective 2 is a far more better amplifier than the Cmoy from technical point, it is just my personal preference that made me love the JDS Labs CmoyBB V2.03R. I have sold my CmoyBB but seriously,I am thinking to get another one,as it provide the smooth and musical sound for me especially the Godsend Bass Boost features,that I am loving more.
Who says so,every guy should be only in love with Cinderella?
It is only personal preference. But speaking to a broader perspective,many will like this amp,and in the price point,I doubt that there will be another headphone amplifier that provide clarity,transparency and neutrality that Objective 2 can give to you. Cmoy can’t touch Objective 2 in this arena.
I love portable amp as they can cope better with low impedance (such as 16 and 32ohm) and high sensitivity earphone/headphone,unlike those desktop amplifier(Which only cope with at least 32ohm impedance earphone/headphone).
I have tried Musical Fidelity Vcan and Vcan II,although in some point Vcan and Vcan Ii provide better score,but when came to clarity,accuracy and neutrality,both of the big desktop amp can’t really match it as well.
I have no problem to recommend this wonderful headphone amplifier to anyone,except those who needs more BASS impact and attack added to the music,maybe should choose another amp.
















Pingback: JDS Labs Objective 2 Amp - HiFi Headphones Forum - online headphone & earphone community forums
the local diyer u meant is leolab?
Hi, I’m trying to choose between this amp, the Bravo Ocean or the Magni from Schiit.
With the HE-400, what do you think would be the best please?
Thx.
Hi, I’m trying to choose between this amp, the Bravo Ocean or the Magni from Schiit.
For the HE-400 what do you think would be the best please?
Hi Jeyckel,
Bravo Ocean is about thick mid and smooth sounding, O2 is a fine choice for the money, but seriously depend on what music you listen to, many of my friends think that O2 is a little bit boring and not really musical.
Thx Su! I’m going for the Bravo Ocean then.
Keep us update!
Hi Su, I was wondering if u would know where i can get a JDS Labs O2 in Malaysia, my friends recommended this model to me since i like listening to details & im not a bass head, i’m looking for portability also.
Yes, you can reach the Malaysia distributor for JDS Labs products at 016850617three
is this a personal number or company ? who should i look for ??
Thanks a lot, i really appreciate it.
This is a personal number that bring JDS Labs products into Malaysia. Don’t worry, just called the number up.