If you son likes the DirecStream, then it's good.The Nordost cable seems more outragous to me though.
Hi Guys,Is it stupid to even consider an R2R dac like the gda600 or a theta gen 3 or 5, for iem listening?
Recently got to hear few DAC+amps :Chord Hugo + HD800 with AK240 as digital source - Wow! what a disgrace to the HD800. The Hugo has a really strange sound. As if a detail filter was applied. Major sounds can be heard but all the little details are totally absent. For the same reason it sounds extremely 2D. Zero layering, depth and flat dynamics. The grain and hardness is not immediately apparent but mids onwards the Hugo definitely lacks lots of refinement. And for $2k it has no right to stay in the market. What a BS product!This was only the second time i heard the HD800 and even tough with the Hugo one can easily tell that this headphone has some of the fastest upper treble.
Hugo and Dave don't use any kind of DAC chip, the analogue conversion is discrete using pulse array. The key benefit of pulse array - something I have not seen any other DAC technology achieve at all - is an analogue type distortion characteristic. By this I mean, as the signal gets smaller, the distortion gets smaller too. Indeed, I have posted before about Hugo's small signal performance - once you get to below -20 dBFS distortion disappears - no enharmonic, no harmonic distortion, and no noise floor modulation as the signal gets smaller. With Dave, it has even more remarkable performance - a noise floor that is measured at -180dB and is completely unchanged from 2.5v RMS output to no signal at all. And the benefit of an analogue character? Much smoother and more natural sound quality, with much better instrument separation and focus. Of course, some people like the sound of digital hardness - the aggression gets superficially confused with detail resolution - but it quickly tires with listening fatigue, and poor timbre variation, as all instruments sound hard, etched and up front. But if you like that sound, then fine, but its not for me.
The PWM/DAC approach is not new, but performance limitations have historically confined itsuse to low-resolution, low-bandwidth applications. The performance of the method relatesdirectly to the ability of the low-pass filter to remove the high-frequency components of the PWMsignal. Use a filter with too low a cut-off frequency, and DAC bandwidth suffers. Use a filter withtoo high a cut-off frequency or with slow stop-band rolloff, and DAC resolution suffers.
Higher Order Low-Pass FiltersHigher order filters offer progressively better stop-band rolloff rates, and hence remove more ofthe unwanted ripple in equation (6). However, design complexities associated with thermal driftand component value variation increase with filter order. Cost and board space consumptionalso increases. At some point, an actual DAC chip becomes a better solution.
