[TunneLVisioN42]

Ill try to be to the point here, I recently upgraded from HD 558's to Hd 650's I love the smooth mellow non-fatiguing treble and everything about this headphone (I think I found my perfect match) SO now I need a Dac/Amp combo to do it justice.

Ill be getting a tube amp for sure I am not sure what so far but I would like to get my DAC figured out first.

I am currently using a Audioengine D1 for both my DAC and amping needs (If you take a look at the pictures one highlights the internals)

http://www.amazon.com/Audioengine-D1-Premium-24-Bit-DAC/dp/B006IPH5H2/ref=sr_1_cc_1?s=aps&ie=UTF8&qid=1342645498&sr=1-1-catcorr&keywords=audioengine+d1

Which I will be returning as there is some issues with clipping and WASAPI with this unit but everything else sounds really good, I have a FiiO D3 DAC sitting around and I was wondering if this a viable option for my DAC needs which seems unlikely since its so cheap, but on the other hand I have heard the DAC chip it uses is quite good so in closing.


How does the[size=x-small] [/size]FiiO D3 [size=x-small]stack up against the [/size]Audioengine D1 in terms of DAC quality only, should the FiiO D3 be unworthy of my HD650's what would be an acceptable choice that atleast reaches or surpasses the Audioengine D1?

My budget is 300$ total for my DAC/AMP needs so whatever is left I am using on a tube amp.

 

[NA Blur]

Well the D1 uses the AK4396 DAC chip which is from Asahi KASEI.  This chip is pretty good, but some claim that it has limited sound staging.  According to the specs it should work fine and I recommend you focus on acquiring a great amp for the HD-650.  The HD-650 is trick because of two main factors.  The first is simply that it sounds veiled.  The audio sounds like it is playing through a thick pillow before it reaches your eardrums.  For me this was intolerable no matter how hard I tried to play it down.  No live music sounds this way and a headphone should not deliver a veiled sound.  That said if you can stand it then there is the second issue.  The second issue is the frequency dependent impedance curve.  See below:
 
http://graphs.headphone.com/graphCompare.php?graphType=0&graphID[]=860
 
As the headphone reproduces specific frequencies the impedance is changing.  This makes it hard for an amp to control the voltage and power needs of the driver.  Because of Ohm's law we know that V=I*R or Voltage = Current ( I ) * Impedance ( R ).  As the impedance increases the current decreasing making it a tad easier for the amp to deliver the necessary voltage to the headphone.  Sounds like a good thing right?  Looking at Joule's law we see that P = I^2*R or P * V^2/R.  Because most amps are constant voltage sources ( set by the volume knob ) we use P * V^2/R or Power = Voltage ( V ) Squared over Impedance ( R ).  Now that you have higher impedance you can easily see that the power drops significantly.  The harder it will be to power the driver and voice coils.  These two laws make impedance a tricky beast.  Back in the day they used high impedance headphones so you could connect many to the same circuit and drive them all with the same voltage and not have to worry about current, but they were rarely concerned with fidelity.
 
Here are three things to make the HD-650 sound better, but to be honest the HD-650 is one of those headphones that you will end up hating or loving.  Time will tell.
 
1.)  Remove the foam insert within each earcup.  This easily pulls out and if you are careful you can easily place it back in.  This will help unfilter the driver giving the headphone less of a veil.
 
2.)  Find an amp that can drive at least 700mW into the headphone out with a voltage of at least 8 volts.  Tube amps can typically deliver more current for less money so perhaps start there.  Testing your HD-650 with a few amps is going to be your best hope in finding one that works well.  For me the HD-650 still sounded dry, veiled, and in order to get decent sound too loud, out of my Grace m903.
 
3.)  Going truly balanced may deliver bass and treble extension for the HD-650 making it more tolerable in the long run.
 
I say keep the D1 DAC and test a few amps and purchase the one you like the most.  If you end up not liking the HD-650 go with a pair of Denon AH-D2000.  They may be just what you end up liking in the end.

 

[TunneLVisioN42]

Thanks for all the info, going through it all now, but I must mention again that keeping the D1 is not an option as it is having clipping issues with WASAPI and this is a known issue I also would like to have a stand alone DAC and I must send the D1 back so I am looking for a DAC option that is just as good in the 100$ price range leaving me 200$ for a Tube amp will update after I am done reading through all the wonderful information you have provided good sir.

Also I do like soundstaging and instrument separation (ALOT) so that is one of my preferred qualities with a new DAC if that is possible.

As for the "HD650 Veil" yeah I heard about it and read a bit before purchasing but I don't seem to mind it although I will look into mods, Funny you should mention the Denons I was really eyeballing them before my purchase but I think I am going to stick with my HD650's for now and look into that later, I will also look into going balanced as time goes on or If it becomes affordable in the near future.

 

[NA Blur]

Try this to help your clipping issue:
 
Turn your PC audio to 75% no more.  Run this through your D1 and use the volume control on the D1 to get the volume you need.  Increase the volume on your PC in 2% increments reducing the volume on the D1.  See if the clipping issue goes away.

 

[TunneLVisioN42]

The clipping issue is only present when using WASAPI which renders software volume control through your PC useless, I have messed around quite a bit and it has been frustrating but the only thing I can do to lessen it is setting Buffer Length to 50MS through Foobar but it is still present at times, thus I really don't wanna have to deal with it which is why I really would rather not keep it.

 

[NA Blur]

Yeah, I hear ya.  If you are not completely satisfied and you know replacing it with something else will fix it then doing just that is a viable option.  Are you sure that swapping to another device will fix the issue?