Originally Posted by derbigpr
I don't know if you still have the amp or not, but I'd like to know if there is any notable channel imbalance on it? I guess since it doesn't use an analog volume pot there shouldn't be any, but I still wonder, since the issue I've had with several more expensive amps (like the Musical Fidelity M1) is that they all seem to suffer from channel imbalance to some extent, which really kills the amp for me, regardless of how it sounds.
Also, did you maybe hear the Nuforce HDP? How would you compare them? Would you say the HAP-100 is a significant step up if we're talking about amp section of the HDP exclusively?
Originally Posted by Armaegis
I have not noticed any imbalance at all. The pot isn't in the signal path, it controls a 100 step digital attenuator. If you listen carefully while playing a sine wave, you can hear the steps, but during normal music you'll never hear it.
I do have the HDP as well. I would say the HAP amp sounds better, but has more limitations. The HDP has more grunt available, but the HAP has a more full bodied sound and doesn't have some of the metallicness of the HDP. The HAP has quite a bit of headroom, but limited current drive so really is meant for high impedance cans. I find it pairs very well with Senns (HD600/650/800) and full sized Beyers (DT880/etc). It does alright with low impedance up to a point, but will clip if you try to drive them excessively loud. But at least the clipping must have some sort of protection in it, so it's a "soft" clip unlike the harsh and hard clip of the DAC-100.
A "significant" step up? Yes... but only with certain cans.
I have no imbalance at any volume here as well.
I also think the HDP is a little more aggressive sounding, and so it's not as much fun as the HAP-100 with cans like my HD800, Grado HF-2, or AKG K240M 600 ohm. I think that the overall detail and soundstage with the HAP-100 is better, but I would guess that power is similar although I haven't tried for max volume on each in a side by side comparison. NOTE - the HDP improves considerably with a regulated PSU like a sigma 11, and comes much closer to the HAP-100 at that point, but at a cost that is higher and does not quite get all the way there.
I think the best phone for the HDP is the HD600/650, like they were made for each other. The best phone for the HAP-100 is the HD800. The difference is that I can also enjoy the HD600 with the HAP-100, but I don't like to use the my HD800 on the HDP.
Both are nice with HE-500 and LCD-2 rev2 but I prefer the HAP-100 due to it's refinement and soundstage. I also prefer the HAP-100 with IEM because there is some very faint hiss with the HDP that isn't intrusive but is absent in the HAP-100, and the HDP does have some low volume channel imbalance (fixed by lowering the PC system volume if using the DAC)
The HDP has more power/current than the specs say, because of a last minute mod that greatly improved the sound right before production started - it will shake your fillings loose with the HD600 at high volumes, and still have good oomph with LCD-2 and HE-500. I should compare them side by-side with low impedance phones someday, but my gear is spread out all over the house.
I have always said that the HDP's DAC was better than it's built-in amp, but the HDP is like buying an "excellent" low-cost DAC at a fair price and getting a "good" amp thrown in for free. And the DAC doesn't need the PSU to sound it's best. The HDP DAC fed into the Schitt Audio Magni amp is an audible upgrade over the built-in amp, but feeding the Schitt Modi DAC into either amp reveals fairly quickly just how much better the HDP DAC is vs Modi or other $200-400 DACs. I recon it's DAC sounds as good as my Pico DAC or a DACport LX DAC, plus it's got an amp that they don't have.
One last thing - if you must have a good budget DAC/amp combo for HD800, and don't need the HDP's optical or coax inputs, and can't afford the HAP-100 to drive them, the newer Icon DAC is a much better choice than the HDP.
It's warmer and smoother sounding for the HD800 (less aggressive, or less metallic as Armaegis might put it) and more powerful and punchy for HE-500 and LCD-2 rev2. It's a better all-around product for getting along with a wider variety of headphones. While the HDP > HAP-100 combo sounds a little better and is much more flexible due to it's inputs, it costs quite a bit more than the Icon DAC if USB alone is all you need. Having tried the HDP > HAP-100, I'd bet that the Icon DAC > HAP would also be great, but that extra 10% in performance is expensive. But add a better DAC to the HAP and you get another 10%, etc, etc... It continues until you have a $4K DAC and $3K amp for another 10%.