[liamstrain]

With those comments in mind (though I would have never considered the M-stage dark, but then I'm coming from tubes), you might consider keeping an eye out, down the line, for a Dynalo based amp (something like the Sheer Audio HA-006+ - http://www.acoustic-fun.com/catalog/product_info.php?products_id=62 )
 
This *should* be an experience closer to the O2, but with more oomph. 

 

[Kouzelna]

Is there a way to mod the O2, since it is a moddable amp, to work with the K702?  What keeps it from working with the K702 you think?

 

[liamstrain]

Unfortunately, I don't know enough about the 02 circuit to even begin to guess. 

 

[Kouzelna]

 
Fixed the issue.  A battery had gotten loose in shipping.  Once I reinstalled it, the problem magically went away.
 
Here's a quote from my newly updated O2 ad:
 
 
Comparison to my M-Stage amp:
 
 
It came down to a serious toss up with the M-Stage, and basically the bottom line is this:
 
The O2 by far has more clarity, detail, and sonic accuracy in my opinion.  It is a great amp. But the M-Stage has a bit warmer, "tube-like" sound, and since I love tubes, I'll stay with it instead.  However, the M-Stage lacks a lot of the accuracy, presence, clarity and detail of the O2 so it is at great sacrifice I do it.  It just boils down to my particular preference for tubes, which I currently can't afford.  So the M-Stage is the one I'll keep, at least until I can afford a WA6.
 

 

[Chris J]

 
Quote:

 
 
OK boys and girls, I spent an hour with them last night side by side, and here's the drill on the comparison:
 
The O2 by far is more clear, neutral and detailed.  The M-Stage is a dark sounding amp, with a more "tube like" character in a sense.  I would choose the O2 hands down because of its truly "transparent" clarity, and its seeming incredible ability to really pump out each and every detail of the recording.  
 
BUT - 
 
The problem I am having with the O2 is that they are not really able to power the K702 as well as the M-Stage.  At least, that is how it seems to me, just from a "hearing" perspective.  This is what I mean:
 
I LOVE the O2.  But there is simply not enough depth and body during more complex parts of songs as you hear with the M-Stage.  When a song really gets going, it seems that part of the bottom drops out, whereas the M-Stage has lots of depth and "uumph," though at with the sacrifice of that pristine clarity and just superb detail that the O2 has.  From my experience with amps and the K702, I am thinking as a relative newbie anyway, that this means the K702 is not being properly driven with the O2.  At least, that is the sound: it seems as if the M-Stage is pumping that K702 full of energy and moving the stuff around in there, whereas the O2 gives it enough juice to play well, but not really "groove" and shake its booty around.
 
Would love comments, but consider the O2 up for sale as of this moment.

How much ya want for the "0"?
 

 

[etomic]

I am new to headphone amps.
 
I need a budget priced headphone distribution amp, and I read that the PreSonus HP4 - 4-Channel Headphone Distribution Amplifier Priced at around $150.00 was a good choice for monitoring voice over recordings and the like.
 
My question is: can this amp work for everyday listening with my Grado sr225 headphones?
or do I need to get something more suited to and dedicated to audiophile use?
 
Just thought I might be able to kill 2 birds with 1 stone.
 
Any help is appreciated.

[size=1.33em]  [/size]

 

[liamstrain]

Generally speaking, It should be fine with the SR225... they do not require much extra effort on the part of the amp. With that said. I do not know the output impedance on the PreSonus, and if it is too high, you might lose some control of the bass on the 225s (which have a very low impedance, and high sensitivity). 
 
With that said, when it comes down to it, distribution amps are designed for one task and single phone audiophile amps for another... they can be pressed into service for the other job, but it will always be just a little beyond what it was meant to do. 

 

[Chris J]

Quote:

I am new to headphone amps.
 
I need a budget priced headphone distribution amp, and I read that the PreSonus HP4 - 4-Channel Headphone Distribution Amplifier Priced at around $150.00 was a good choice for monitoring voice over recordings and the like.
 
My question is: can this amp work for everyday listening with my Grado sr225 headphones?
or do I need to get something more suited to and dedicated to audiophile use?
 
Just thought I might be able to kill 2 birds with 1 stone.
 
Any help is appreciated.

[size=1.33em]  [/size]

You're not allowed to ask Grado questions in the K702 thread!

 
Just kidding!  Let us know how it works out if you get one. The price looks very reasonable.
 
A lot of guys report that Grados are very easy to drive.
 

 

[Chris J]

Quote:

Is there a way to mod the O2, since it is a moddable amp, to work with the K702?  What keeps it from working with the K702 you think?

Just a guess, if you are really handy and have a +/- 9 Vdc power supply you could try substituting that power supply for the two 9 Volt batteries.
Has anyone ever tried this?
 
I agree, the M Stage sounds somewhat dark, which is probably why us K701 and Q701 owners like the M Stage, good synergy.

I've tried different Op Amps, the sound changes a bit, but the M atrix still sounds dark.
This could explain why the M Stage is not my preferred amp for my DT880 600 ohm cans as they are a fairly neutral can.
 

 

[Kouzelna]

The person I got the amp from uses his own O2 for his Grado 325i.
 
Funny, but the M-Stage really improves over time as it warms up.  It's weird to me as it's a SS amp, and I thought only tube amps benefit from "warming up."  But the M-Stage does actually open up and produce more clarity and treble when it's been on a while, and, warmed up.  
 
 
 
As for my O2 price, check out my ad here:
 
http://www.head-fi.org/t/592878/fs-new-objective2-o2-amp-or-m-stage-w-gold-desktop-case-115-incl-s-h
 
I'm only asking a measly $115 which inlcudes all shipping to CONUS (Continental USA).  That is $50 less than buying it from JDSLabs, with shipping.  
 
The amp is brand new.  I professionally ship.

 

[etomic]

Here are some of the specs for the PreSonus distribution amp I was looking at:
 
PreSonus HP4 - 4-Channel Headphone Distribution Amplifier

Specifications:

Maximum Output Level -80dB to +10dB; 51 Ohm Impedance

Frequency Response 10Hz to 50kHz

Noise -98dB

THD + N 0.002%
 
....... would this be an improvement to listening to my Grado sr225 headphones without a amp?  or should I continue searching for a budget audiophile headphone amp?
Since I need an distribution amp anyway, I still hope I can kill (2) two birds with (1) stone.
 
Any input appreciated.

 

[Kouzelna]

Does anyone have any experience with using a Woo WA6 and the AKG K702?
 
Do you guys feel this would be a good match-up?  As I understand, the WA6 is the amp that could work well with the K702.  
 
In time, I hope to get one and compare it to my M-Stage and go from there.  (My dream setup is the T1 and WA6).

 

[liamstrain]

I think Dubstep girl has this combination. Certainly it *should* work well. The WA6 is transformer coupled and noted for being a pretty clean sounding amp. 

 

[Kouzelna]

Oh heck, I forgot.  I did read that smashing review by Dubstep Girl, and she did love the combo.  However, she had the WA6+, which is like 6 times the price of the WA6.  
 
Would the cheaper WA6 still be the same basic style of amp that would work?  I realize the WA6+ is a gigantic sized "premium edition" of the standard model, but I'm not sure that it changes the basic design of the amp enough to kill the basic synergy of using it with the K702.

 

[liamstrain]

I don't think there would be a significant difference in performance between the two WA6 models when paired with the 701/2.