Review: NwAvGuy's O2 DIY Amplifier - Page 79  

Is anyone using these with Grados?

Does it sound good?

Would really like to hear from someone that has tried both the Little Dot 1+ and also that has tried the O2.

Just trying to decide how to amp my Grados.  Right now I have SR60s and hope to procure RS1i next.

Quote:

Originally Posted by wullymc 

Is anyone using these with Grados?

 

Does it sound good?

 

Would really like to hear from someone that has tried both the Little Dot 1+ and also that has tried the O2.

 

 

Just trying to decide how to amp my Grados.  Right now I have SR60s and hope to procure RS1i next.

Chances are it will sound indistinguishable from your Clip+.

Quote:

Originally Posted by wullymc 

Is anyone using these with Grados?

 

Does it sound good?

 

Would really like to hear from someone that has tried both the Little Dot 1+ and also that has tried the O2.

 

 

Just trying to decide how to amp my Grados.  Right now I have SR60s and hope to procure RS1i next.

I've used the O2 with the Grado / Magnum headphones.  It pairs well with them.  I have not tried the Little Dot.  Also, as a question, why consider the RS1i, when you can get some Magnums for about 350?  Or, spending 550 on used RS1i headphones also puts you in the range for some used orthodynamic headphones such as offerings from HifiMAN.  I used to really love the Grado sound - then, the Magnum sound.  However, after getting hooked on the orthodynamics, it's hard for me to turn back. Then again, some orthodynamic headphones might require a bit more than the O2 to power them right, too.

I tried the O2 with the RS1i, pretty good combo, you won't be disappointed. I do like the Asgard a bit better for something like the SR325is though, adds a touch more warmth and bottom end and tames the treble a bit.

Has anyone used the O2 with a JH13? I've tried searching the thread but couldn't find any mention of it.

I'll have to agree with wje here, especially the HE500 should be on your list of considerations.

Just see what Tyll says about then here! And they cost practically the same as a set of RS1i.

Thanks guys for your feedback!

Things to think about.  I mostly listen to prog rock that is why I am thinking of sticking with Grado! :)

no, you can't use more then 2.5x with a dac or 2.0v RMS source. So it would not be useful with HE6 either. The only reason the high gain is needed is for an ipod, or other weak device that only has .05v output. If you ever plan to use it mobile, with a weak source, it's good to keep the high gain around. You may find 1x or 2.5x insuffcient with an ipod.

Quote:

Originally Posted by Maxvla 

Guessing you meant .5v, .05v is pretty weak, heh.

Some IEMs will get by with just .05V...

Quote:

Originally Posted by Eric_C 

Has anyone used the O2 with a JH13? I've tried searching the thread but couldn't find any mention of it.

My friend seemed happy with it on a JH16, if that helps at all.

The Grado's sound like crap so you need an amp that sounds like crap (but opposite crap) to try and even everything out?

From the photo below, your Epiphany amp's 'low' gain is 1.0x, evident by the absent R17/R21 resistors...

The potentiometer taper no doubt affects attenuation. A 3B taper is the standard volume taper curve. Most of our O2's use the default recommended Alps pot, RK09712200MC, which has a 15A taper. We've been using RK09712200MY's temporarily (Voldemort's 3rd alternative, a 3B taper) while the -MC parts were on backorder.

You guys must be listening at incredibly low volumes! I didn't notice a difference after we switched from 15A to 3B. Granted, we use full size headphones on the test bench; nothing less than 64 ohms. 
 

Quote:

Originally Posted by Twinster 


Looking at the picture and just realized that the gain resistors were not in a socket (as per the picture of the one Voldemort did). So I assume you just cut the resistors that was in place for the 6.5x gain?

Quote:

Originally Posted by Naim.F.C 

Ok DIY Detectives. Here are the two boards, top one JDS (2.5x/1x Gain), bottom one Epiphany (Unknown Gain). Can anyone figure out why the Epiphany requires such a good degree more volume, even with the JDS O2 at 1x Gain?

 

 

JDS O2.

 

 

 

Epiphany EPS-O2

 

 

 

And for reference, the original default design.

 

 

Thanks!

Quote:

Originally Posted by Naim.F.C 

Honestly speaking, I've never even had to use 2.5x gain, not with the LCD-2's or T1's. I personally think 6.5x is overkill unless you're rocking the HE-6 or something or want to demolish your hearing. Then again I listen at quite low volumes.

 

 

yeah, i clipped the gain on my O2, and still never get the volume past 10oclock on low gain with my LCD-2's, and with my ES5 customs, I can barely touch the volume at all before its too loud. 

of course this depends on my source - the above is true when running from my computer, optical to a bifrost dac, and into the O2. 

When i run a line out from my ipod touch, i get a much larger volume swing due to the ... umm.. lower voltage output?  yeah i think thats it.