Objective 2 (and O2+ODAC) Impressions Thread

[Cankin]

Thanks, had a look, still gonna get the O2

Just a quick question before I order, if I get the 2.5 x- 6.5x gain can I open it up and change the resistors out to change the gain? it doesnt bother me much if I have to resolder

 
Make sure to check the warranty policy before you cut the resistors.

 

[Aussiejuggalo]

Make sure to check the warranty policy before you cut the resistors.

Yeah I will, just wanted to know if I could in case the standard 2.5x - 6.5x causes clipping on my DT880s

On another note, I'm about to pull the trigger...


Getting a Hatchetman engraved because why not?

 

[Aussiejuggalo]

Got my O2 today , awesome looking amp and sounds great, dont have clipping on either gain setting which is good to

Spoiler: Pics

Yeah... this was taken upside down and just flipped lol



The setup looks awesome

Think I may end up getting rid of my soundcard and going full external but still not 100% sure on that yet :redface:

Edit, if your using the O2 on just mains power is it ok to keep the batterys in or just take them out? nevermind, ended up taking them out

 

[kcdecker]

I ordered my O2 yesterday and it should arrive tomorrow...excited!
 
This is a relatively small appreciation thread...is the O2 strangely unpopular?

 

[JakeJack_2008]

  I ordered my O2 yesterday and it should arrive tomorrow...excited!
 
This is a relatively small appreciation thread...is the O2 strangely unpopular?

No, you are terribly wrong. The O2 and ODAC are very popular here.
Way over one year,  I bought them from JDS Labs  - what a great place to buy  -  and I am very happy.
I'm using the O2 and ODAC  with my Toshiba Satellite laptop and the DT 880 (250 Ohm) cans.
The system sounds great.
 
Proud and Happy owner of the JDS O2 and ODAC,
 
JJ

 

[jseaber]

  I ordered my O2 yesterday and it should arrive tomorrow...excited!
 
This is a relatively small appreciation thread...is the O2 strangely unpopular?

 
As JakeJake describes, O2 is a popular design. The O2 and ODAC cover a  broad range of applications (portable and desktop, amplifier, or amp+DAC, etc.), so discussions cover a wide number of threads and forum categories. Thus, this thread is a small representation of O2 users.
 
On a somewhat related note, here's a look at O2 on display at CanJam this morning:
 

 

[PurpleAngel]

  I ordered my O2 yesterday and it should arrive tomorrow...excited!
This is a relatively small appreciation thread...is the O2 strangely unpopular?

 
The original designer of the O2 & ODAC was at one time totally banned from Head-Fi, even talking his name was banned.
So for a time he was referred to as Lord Voldemort or He who can not be named.
 
Here is a large thread dedicated to the Objective 2 & ODAC
http://www.head-fi.org/t/616331/o2-amp-odac

 

[kcdecker]

I ordered the O2 from JDSLabs and was surprised at the free engraving option.  Being that if I were to start thinking about the engraving, I'd drive myself crazy for weeks trying to think of what to engrave, I just typed in "random quote" on google and ended up with, "Remember my name."  How appropriate for an amp designed by he-who-cannot-be-named...
 
Because I'm exceptionally lazy at the moment, my exposure to the O2 is limited to the headphones within reach of my living room chair, which would be the Mad Dog (3.2).  Despite only about 3 minutes of listening, it's now my new favorite amp.
 
Score one for NWAVG--I mean, the dark lord...

 

[leithen]

I have an O2 combo from JDS labs that I quite like. I just decided to try the DAC alone, hooked up to an RSA Raptor tube amp and I was a bit surprised at the levels of distortion I was hearing in the bass. If I turn the volume down on the PC and then compensate by increasing the volume on the raptor, things sound better, however, I was under the impression that one should always max out the volume on the PC when running it into a DAC. Does anyone have any ideas about this?

 

[jseaber]

  I have an O2 combo from JDS labs that I quite like. I just decided to try the DAC alone, hooked up to an RSA Raptor tube amp and I was a bit surprised at the levels of distortion I was hearing in the bass. If I turn the volume down on the PC and then compensate by increasing the volume on the raptor, things sound better, however, I was under the impression that one should always max out the volume on the PC when running it into a DAC. Does anyone have any ideas about this?

 
Please see connectivity information here:
http://www.jdslabs.com/pdf/Instructions_O2-ODAC.pdf
 
ODAC performs correctly when connected to a single load. Multiple, paralleled loads will produce severe distortion until PC volume is reduced. You'll need a Dedicated DAC Line-Output on O2+ODAC to truly isolate ODAC for use with external amps.

 

[leithen]

   
Please see connectivity information here:
http://www.jdslabs.com/pdf/Instructions_O2-ODAC.pdf
 
ODAC performs correctly when connected to a single load. Multiple, paralleled loads will produce severe distortion until PC volume is reduced. You'll need a Dedicated DAC Line-Output on O2+ODAC to truly isolate ODAC for use with external amps.

I'm not sure I understand. The ODAC combo I have does have a dedicated line out. I've connected it by running the USB into the ODAC and the line out into the external amplifier. Based on my read, you're indicating that I am correct to turn the volume down a little on the PC? I was mainly curious why this is the case, as I've always been under the impression that one should have the volume from the PC at max when connecting to an external DAC...?
 
Thank you for your feedback - much appreciated!

 

[jseaber]

  I'm not sure I understand. The ODAC combo I have does have a dedicated line out. I've connected it by running the USB into the ODAC and the line out into the external amplifier. Based on my read, you're indicating that I am correct to turn the volume down a little on the PC? I was mainly curious why this is the case, as I've always been under the impression that one should have the volume from the PC at max when connecting to an external DAC...?
 
Thank you for your feedback - much appreciated!

 
Connect a 3.5mm cord into the right, 3.5mm jack. This will mechanically disconnect ODAC from O2 and enable proper operation of the Dedicated Line-Output.

 

[leithen]

   
Connect a 3.5mm cord into the right, 3.5mm jack. This will mechanically disconnect ODAC from O2 and enable proper operation of the Dedicated Line-Output.

Yes, this is what I've done. But that doesn't answer my volume question...?

 

[jseaber]

  Yes, this is what I've done. But that doesn't answer my volume question...?

 
Please post a picture; I think there's confusion from both sides.
 
Your question was answered in post #40. It's only necessary to reduce volume when ODAC is connected to multiple loads. Your external amp is a secondary load if O2 is not bypassed. The DAC is able to produce clean audio at 2VRMS when connected to a single amp. Its internal charge pump struggles under lower impedance loads (paralleled outputs), so DAC output voltage must be reduced to achieve clean output. This is easily accomplished by reducing PC volume.

 

[leithen]

   
Please post a picture; I think there's confusion from both sides.
 
Your question was answered in post #40. It's only necessary to reduce volume when ODAC is connected to multiple loads. Your external amp is a secondary load if O2 is not bypassed. The DAC is able to produce clean audio at 2VRMS when connected to a single amp. Its internal charge pump struggles under lower impedance loads (paralleled outputs), so DAC output voltage must be reduced to achieve clean output. This is easily accomplished by reducing PC volume.

 
Well, now I feel silly. I thought that the ODAC did not require being plugged in to a power source, when bypassing the O2. However, this is clearly not the case, as plugging in solved the problem and removed all distortion.