which pair of headphones are you intend to power with the UD301

Yeah, like they say many ways to skin the cat. DC power is suppose to give the cleanest signal.

Just a basic Senheiser HD650. I will not buy HD800 for now as most of the time the HD650 will be in office. While at house, I prefer to use speakers.

The headphones output power of the UD301 is rated at only 100mW per channel into 32ohms far too low to make the HD650 sing

Complication is the key word here. It's harder to make a streamlined extremely clean build without the extra necessities. For example, the inside of a Schiit amp and that of a DIY amp. Most boutique custom amps inside is extremely messy and DIY like. Schiit is clean as hell. That's why I respect schiit. Good value for money with fantastic build quality.

And they do. High end brands like goldmund use to rip entire sony boards out and call it theirs, and charge 10X more. A LOT of high end brands have similar board and internal designs.
This is the internals of a 110K Vivaldi DAC. Simple, clean, non fussy.

www.thanhtungaudio.com/media/product/606_dcs_vivaldi_dac_internal_sjpeg.jpg

This post has been edited by Sentinel92: Apr 28 2015, 10:54 AM

That's what I read from their website;

Even the headphone amplifiers used in the CCLC circuits are of dual monaural design. The 100mW + 100mW output (at 32 ohms load) headphone amplifier uses CCLC (Coupling Capacitor Less Circuit) technology. In conventional headphone output circuits, a capacitor is used for output-stage coupling, and so the sound is unavoidably colored. When the capacitor is combined with a high-pass filter this often results in phase lags, or low frequency level degradation. With CCLC the negative impact of capacitors on sound quality is eliminated, providing full low-frequency sound and a responsive headphone listening environment with great spatiality.

Doubles as a no-compromise, high-performance headphone ampIn addition to the dual monaural headphone circuits, there are options to switch off the XLR and RCA outputs on the rear panel. By cutting the power supply and isolating those circuits that are unrelated to the headphone output, the performance of the UD-301's headphone output can be maximized. This feature also makes the headphone amp very easy to use as the volume control for the headphones is completely separate from the output mode (Fixed, Adjustable or Off) on the rear panel.

Headphone output
Connector 6.3mm(1/4") stereo phone jack
Maximum output 100mW + +100mW (32 ohms with load, distortion rate 0.1%)
Compatibility impedance 8 ohms to 600 ohms

As you can see, it mention about headphone up to 600 ohms supported~ But only UD301.. Not UD501

Inside too simple... Will feel kind of cheated and buying for nothing...

Having volume is one thing, having enough current for it to sing is another Bring your pair of HD650 along and compare the headphones output of both the UD301 and the Aune T1

This post has been edited by E1 - AKG: Apr 28 2015, 11:54 PM

Hmm... ok. I guess manufacturer should be more transparent like maybe putting recommended headphone and also some not recommended headphone so consumer have better ideas...

Are you buying for the sound quality or not ?

I think quality is highly subjective depends on;

(1) Components quality?
(2) Design quality?
(3) Listenner taste and expectation?
(4) Own speaker, amp and cables used.

Example; The Krell 300i was known as affordable high end amp. Once listened, yes, very powerful low freq response, like everything is in control with tight bass. Kind of like none-stop want to show its muscle. And the sound is even more powerful than the famous Marantz PM8005 (I like it). But... to me not that musical... Just imagine a strong guys every day, every hours none-stop want to show off muscle here and there... For a while, yes impressed. But for long, who can tahan that? Pairing with Ayre pre-amp in indeed soften them. But end up like pondan...

It mean personal taste is subjective. Example: some people like Krell sound... some people like pondan sound.. some people (including I) prefer sweet sound (maybe because of this overweight), some prefer ultra-unrealistic-unnatural-super-detail sound etc...

For me, I like extended sound stage, acceptable amount of details (no need exessive until unnatural like those ESS9018) and towards smooth and sweet sounding, which can make me smile... relax...

Anyway, when have time will try UD301. Since no hifi set there, thus can only test with headphone. But problem is... I know a lot of amp/dac sound very much different with speakers versus headphone. My PM6005 with its built in DAC consider dissapointing in headphone department.

Well if you said it to be so subjective then why post here to ask?