spartan123
100+ Head-Fier
- Joined
- Jan 8, 2006
- Posts
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- 16
This looks interesting:
AUNE Mini USB DAC + Headphone Amplifier MK2
AUNE Mini USB DAC + Headphone Amplifier MK2
Originally Posted by mrarroyo /img/forum/go_quote.gif David, if I may suggest I would encourage HLLY to install a socket for the Headphone amp and to provide the user w/ a list of op-amps that would be compatible. This way the end user could experiment with a few op-amps and find the best sound for him/her. The unit has been burning in since I received it 9 days ago, thus an additional 215 hours for a total of about 315+ hours. I did a quick comparison with an external amp being fed w/ the line out of the HLLY and the internal amp is a lot better than when I first listened to it. I will say that the OPA2134 is good but not my favorite op-amp, for example I prefer: AD8620, LM4562, AD8656, AD8066, to name a few. Of course it depends on the overall circuit implementation and the mentioned op-amps should be taken with a grain of salt. Another item that would affect the sound is how clean or dirty the A/C is. I have a filter installed as well as a ferrite core around the power cable supplying the HLLY. These two items may be helping. More to come. |
Originally Posted by spartan123 /img/forum/go_quote.gif can the current chips be replaced with the new ones? |
Originally Posted by david-gao /img/forum/go_quote.gif OK, Miguel! We will have tube buffered DAC soon, We will send it to you for test and advice! By the way, do you test the power amplifier? David gao |
Originally Posted by mrarroyo /img/forum/go_quote.gif Hi Davie, what power amplifier. The back of the HLLY DMK-IV I have does not have speaker outputs. If you mean the line out, yes I am using the line out to feed a Graham Slee Solo SRGII. I just did an small back and forth between the HLLY headphone out and the Solo SRGII being fed via the HLLY line out. I used two headphones a wooded SR80 and the HE5. The source was a Philips DVD player that has "been around for a while". Any ways the result was consistent, the bass is deeper/tighter/punchier with the Solo SRGII, the soundstage was better defined w/ depth and width on the Solo SRGII, the high mids and the highs were pretty even, and the Solo SRGII exhibited a bit better musicality. I should mention that it was easier to hear these differences with the wooded SR80 Grado than the HE5. What does this tell me? That the HLLY DMK-IV is a good deal. The DAC section is very good much better than the price would lead you to believe. The headphone amp now with almost 400 hours is much tighter, clearer, and w/ more detail than at 100 hours of burn in as I received it. No, it is not a killer unit since the Solo SRGII w/ PSU1 sounds better but it should since it sells for $700 versus the price of the HLLY DMK-IV. If/when David can improve on the amp out section then it will be a very nice unit to own for those wanting a second rig or starting out on the hobby although I feel the DAC section will keep many very happy for a while. BTW David, if your new unit has speaker outputs then it would be an interesting option for those who own an AKG K1000. It would make a nice office rig to cover a few scenarios. |