[uncola]

Let me go test it right now and I'll write my experience
Ok I tested the line-in using my phone as a source, no issues with left and right channels having differing volume levels.  Which is funny because using my usb dac with the rca in ports on the back does give me channel imbalance issues on the first two clicks of the volume pot.  But my phone is a weaker source so I am several clicks above 0 on the volume pot where there's no imbalance at all.  The way I understand it, it's normal for an analog potentiometer to have some imbalance near 0 volume.. and my usb dac does 2.1v out so that makes sense to me.. 
 
stupid video I made

 

[BeatsWork]

  Let me go test it right now and I'll write my experience
Ok I tested the line-in using my phone as a source, no issues with left and right channels having differing volume levels.  Which is funny because using my usb dac with the rca in ports on the back does give me channel imbalance issues on the first two clicks of the volume pot.  But my phone is a weaker source so I am several clicks above 0 on the volume pot where there's no imbalance at all.  The way I understand it, it's normal for an analog potentiometer to have some imbalance near 0 volume.. and my usb dac does 2.1v out so that makes sense to me.. 
 
stupid video I made

Hmmm. Looks like I've got a bad socket then. It's an enclosed component so I may just remove and re-wire with two more RCA inputs so that I can switch between 2 DACS.   Thanks for checking-appreciated!

 

[BeatsWork]

  My A1 has no hum with the HE-400 (which are 35 Ohms), either... lt appears that l only get the hum on low impedance, dynamic HPs...

No hum with HE-500.

 

[IYAshike]

l came to the conclusion that it is not about the impedance of the HP, but the sensibility. For example, with the Beyers DT-770 PRO (rated at 96db) the hum is hardly audible (although it is there). 
 
The HE-500 are rated at 89db; the HE-400 are 92.5db... 
 
In any case, some people seem not to have hum, at all. lt may [size=13.1428575515747px]also[/size] be the tube you get (some might be better than others). 
 
l bought a new DAC/amp, so l haven't listened to the A1/D2 since July. l will sell it sooner or later, l guess...

 

[Asudef]

I'm highly considering this amp to drive my bookshelf speakers but they're rated at 87db @ 4Ω and 100W. The manual specifies at least 50-100W but I read that Wattage doesn't really mean that much.
Are there similarly priced tube amps that could drive my speakers?
 
Would this amp drive my speakers well? The room is only about 160sf in size.
How does this sound with the D2 DAC?

 

[uncola]

I use psb image b5 bookshelf speakers that are 89db and 6 ohm nominal with no problem..  haven't tried it with any 4 ohm speakers though

 

[Jubijub]

hello,
 
I'm considering this amp with a MavAudio D2 plus as a DAC, using a SoundBlaster Z as the source/DSP.
 
I want to drive good headphones (not bought yet, considering Sennheiser HD600 or better), and my speakers, which are already amplified. (i use them 10% of the time, but still)
 
Is there a way I can get the signal out to my speakers so that : 
- I don't fry them (they accept jack 3.5mm, but I assume I can use a simple converter RCA/Jack)
- plugging headphones disable the sound on the speakers