O2 AMP + ODAC
Jan 21, 2014 at 8:51 AM Post #1,891 of 5,671
Is it a good idea to keep the output of odac at 1.0V for 1.0x or 2.5x gain on the O2?


Thanks!
 
Jan 21, 2014 at 9:06 AM Post #1,892 of 5,671
No, optimum is to keep the ODAC at 100% volume = 2v, and then adjust gain and volume on the O2 accordingly.
 
As i said previously, for low impedance cans like 32ohm Grados 1x gain is fine, for 300ohm cans like HD650's 2.5x is about right.  I dont see any reason to use any higher gain unless your source is low power and you need to make up for it.
 
Jan 21, 2014 at 12:34 PM Post #1,893 of 5,671
No, optimum is to keep the ODAC at 100% volume = 2v, and then adjust gain and volume on the O2 accordingly.

As i said previously, for low impedance cans like 32ohm Grados 1x gain is fine, for 300ohm cans like HD650's 2.5x is about right.  I dont see any reason to use any higher gain unless your source is low power and you need to make up for it.


I thought I didn't need 6.5x but classical music, especially slow movements of piano concertos are really quiet.
 
Jan 21, 2014 at 1:06 PM Post #1,895 of 5,671
I thought I didn't need 6.5x but classical music, especially slow movements of piano concertos are really quiet.

 
 
You don't, you just need to turn the volume knob a bit more..
 
Jan 21, 2014 at 1:59 PM Post #1,896 of 5,671
What about congestion, bloat and sibilance you reported before?


I'm not sure why but this is less of a problem when the volume is between the 10-2 o clock position than when it is below the 9 o clock position on 6.5x gain. Another observation is this bloating issue is more prevalent on pop, rock, commercial music. I don't hear the bloat too much if at all on classical recordings. Maybe the soundstage? Recording space? Mix? I don't know. I'm not an engineer so I don't know the physics or math. Just my observation.
 
Jan 21, 2014 at 2:40 PM Post #1,897 of 5,671
I'm not sure why but this is less of a problem when the volume is between the 10-2 o clock position than when it is below the 9 o clock position on 6.5x gain. Another observation is this bloating issue is more prevalent on pop, rock, commercial music. I don't hear the bloat too much if at all on classical recordings. Maybe the soundstage? Recording space? Mix? I don't know. I'm not an engineer so I don't know the physics or math. Just my observation.

 
Volume @ 10-2 o'clock at 6.5x... with an ODAC...
 
8-O
 
What cans are you using? I guess the only thing I'd notice in that circumstances with any of my phones would be the popping sensation when my eardrums split...
 
Joachim
 
Jan 21, 2014 at 4:43 PM Post #1,899 of 5,671
Volume @ 10-2 o'clock at 6.5x... with an ODAC...

8-O

What cans are you using? I guess the only thing I'd notice in that circumstances with any of my phones would be the popping sensation when my eardrums split...

Joachim


Classical music. Slow movement of a piano concerto. 2nd movement of Ravel piano concerto in G with Thibaudet is really really quiet.
 
Jan 21, 2014 at 6:08 PM Post #1,900 of 5,671
Classical music. Slow movement of a piano concerto. 2nd movement of Ravel piano concerto in G with Thibaudet is really really quiet.


Listening to it atm... spotify only unfortunately but still nice. ODAC at 100%, O2 on 2.5x. Highest I can bear with my K240 Sextett, which is not really efficient either although no comparision to an HE-6, is around 12 o'clock (and actually too loud for an adagio and way too loud for my ears around 6:30).
 
And now I was in for a painful surprise when spotify gave me a loudness war commercial - luckily I had already turned it down a bit to 10 o'clock but it still hurt...
 
So the question stands - what cans need 6.5x and up 2 o'clock even with Ravel's piano concert in G - 2. adagio assai with Thibaudet :wink:
 
Joachim
 
Jan 21, 2014 at 7:12 PM Post #1,901 of 5,671
 
Listening to it atm... spotify only unfortunately but still nice. ODAC at 100%, O2 on 2.5x. Highest I can bear with my K240 Sextett, which is not really efficient either although no comparision to an HE-6, is around 12 o'clock (and actually too loud for an adagio and way too loud for my ears around 6:30).
 
And now I was in for a painful surprise when spotify gave me a loudness war commercial - luckily I had already turned it down a bit to 10 o'clock but it still hurt...
 
So the question stands - what cans need 6.5x and up 2 o'clock even with Ravel's piano concert in G - 2. adagio assai with Thibaudet :wink:
 
Joachim

 
Spotify (using premium) is way louder than my CD ripped to itunes. On spotify, I have it up till 9.30 oclock max on 6.5x and 11.30 on 2.5x BUT on my itunes I need it to be 2 oclock on 6.5x. So you don't need the 6.5x gain there. :wink:
 
Jan 21, 2014 at 11:16 PM Post #1,902 of 5,671
Besides recharging the battery, the AC adaptor will allow you to accept true line out (2V) without fear of clipping the input stage. It is recommended to use AC adaptor  when you are going to use it with ODAC or any desktop source. I think the battery mode will only accept 1.5-1.7 V of input before clipping. In other words, you can accept louder source and therefore get it louder at output stage using the AC Adaptor.
 
Jan 22, 2014 at 6:52 AM Post #1,903 of 5,671
No, optimum is to keep the ODAC at 100% volume = 2v, and then adjust gain and volume on the O2 accordingly.

As i said previously, for low impedance cans like 32ohm Grados 1x gain is fine, for 300ohm cans like HD650's 2.5x is about right.  I dont see any reason to use any higher gain unless your source is low power and you need to make up for it.
I have an O2/ODAC combo and back when I bought it I had no idea what the gain setting was so I got one with the default 2.5x and 6.5x gain. I'm using low impedance headphones (Grados). Am I ruining the sound quality by using higher gain settings?
 
Jan 22, 2014 at 8:29 AM Post #1,904 of 5,671
Its real simple, start with the lowest gain setting, use the volume control to set the music to what you like for reasonable listening so you wont KILL your hearing over time,
 
If that works there is NO need for higher gain.
 
I run my T90's at unity gain and can blast my head off!!
 
Alex
 

Users who are viewing this thread

Back
Top