[HeadphoneAddict]

Most of the changes are in the 1st 100 hours, and it's mostly extra refinement, openness and depth to the sound. I can say I like it more with the more hours I put on it, but that may just be my ears burning in.

 

[bcwang]

AustinHorn,

I don't think the bel canto link could possibly reduce hiss for my situation. The hiss I'm hearing is not from the source material, but is simply the noise floor of the HDP itself. I can hear it the amp off, and nothing connected to it except the power supply.

HeadphoneAddict,
I've tried the shure attenuator that comes with the headphones, and it seemed to dramatically decrease sound quality when I got it to the point of no hiss. Unless the shure one is much worse quality, I don't think the volume attenuator solution will work. For now, I can connect my tomahawk through the rca outputs if I need to use IEMs with it. But I haven't used IEMs in a while now so I haven't been too concerned with it.

As for changes, I can't comment on it because the first few hundred hours it's gone through was when I was still trying to sort out the hiss issue, I probably put in a couple hundred hours by the time I got down to listening to it for real.

Right now I'm trying to sort out why different digital input methods sound different, why different players (foobar vs winamp) sound different, and why different USB cables sound different. I haven't really officially reviewed any equipment yet because it seems all these things that shouldn't matter, really seem to make a difference and make a fair comparison between two pieces of equipment very difficult. All I can say right now is the HDP sounds very pleasing to me through the HD800.

 

[djbnh]

Interesting read regarding hiss for some and not others. I'm going to have to go the manufacturer's site to read S/N specs.

edit: SNR > 100dB; read the IEM related notes, too. Thanks for the info.

 

[etnt]

Anybody's HDP gets warm so long as the power is plugged in, even when it is not in use? Mine is and I'm finding it strange.

 

[bcwang]

Quote:

Originally Posted by etnt /img/forum/go_quote.gif Anybody's HDP gets warm so long as the power is plugged in, even when it is not in use? Mine is and I'm finding it strange.

Define not in use. If there is no sound playing but the amp is on, it is still using power. If the amp is off, it should be cool though I haven't checked because mine is never off. The headphone amp is a class A design so it actually generates more heat inside the case if it is not playing or playing at a low volume as all the energy is being dissipated inside the case. Also, it seems to me it gets hotter when a low impedance headphone is connected to it than a high impedance one. At least this is my observation from my one day using a high impedance headphone with it, where it stayed cool the whole time. This contrasts with my normal varying heat throughout the day depending on the music it's playing and volume setting.

 

[AustinHorn]

Quote:

Originally Posted by bcwang /img/forum/go_quote.gif AustinHorn, I don't think the bel canto link could possibly reduce hiss for my situation. The hiss I'm hearing is not from the source material, but is simply the noise floor of the HDP itself. I can hear it the amp off, and nothing connected to it except the power supply. HeadphoneAddict, I've tried the shure attenuator that comes with the headphones, and it seemed to dramatically decrease sound quality when I got it to the point of no hiss. Unless the shure one is much worse quality, I don't think the volume attenuator solution will work. For now, I can connect my tomahawk through the rca outputs if I need to use IEMs with it. But I haven't used IEMs in a while now so I haven't been too concerned with it. As for changes, I can't comment on it because the first few hundred hours it's gone through was when I was still trying to sort out the hiss issue, I probably put in a couple hundred hours by the time I got down to listening to it for real. Right now I'm trying to sort out why different digital input methods sound different, why different players (foobar vs winamp) sound different, and why different USB cables sound different. I haven't really officially reviewed any equipment yet because it seems all these things that shouldn't matter, really seem to make a difference and make a fair comparison between two pieces of equipment very difficult. All I can say right now is the HDP sounds very pleasing to me through the HD800.

BC, I know that there has (& probably always will be) a running argument about whether cables do or should make a difference in the sound one gets from sources. I have to admit I come down heavily on the side of those who do feel cables can make a huge difference. I have found that true with the hdp & is another reason I'm interested in the power supply JasonL has been talking about. I'm hoping (Jason are you listening) that the power supply will allow for 3rd party power cables. I'm using Shunyata Anacondas on all my sources, including my dac1 hdr, and find they make a big difference over stock cables. My RCAs/USBs are Kimber Select & each is a step up from standard digital cables. I think I've spent more $$$$ on cables than anything else & I don't feel the improvements I've seen are subjective. Cables (speaker, interconnects, digital, & power) I feel are as important to the sound you get as the gear you buy. So I don't think it is your imagination that you're hearing different sound with different gear. You just need to decide which combo gives you the sound you like best. Based on my experience, that is a never ending quest for perfection. Heck I even switch speaker cables on my HT system depending on whether I'm listening to music or watching a movie, esp. an action movie. It is more about the music than the movie, but speaker cables also make a noticeable difference & if anyone but me is watching/listening, I want them to hear what ever it is as its very best. I know crazy! If it is just me, I use headphones and I'm happy!

 

[etnt]

Quote:

Originally Posted by bcwang /img/forum/go_quote.gif Define not in use. If there is no sound playing but the amp is on, it is still using power. If the amp is off, it should be cool though I haven't checked because mine is never off. The headphone amp is a class A design so it actually generates more heat inside the case if it is not playing or playing at a low volume as all the energy is being dissipated inside the case. Also, it seems to me it gets hotter when a low impedance headphone is connected to it than a high impedance one. At least this is my observation from my one day using a high impedance headphone with it, where it stayed cool the whole time. This contrasts with my normal varying heat throughout the day depending on the music it's playing and volume setting.

Not in use as in amp is off, no lights on the front. No headphone plugged in; USB, spdif, analog rca plugged in as input; analog rca plugged in as output.

 

[AustinHorn]

Quote:

Originally Posted by etnt /img/forum/go_quote.gif Anybody's HDP gets warm so long as the power is plugged in, even when it is not in use? Mine is and I'm finding it strange.

I've had mine going 24/7 for a week & it is cool to the touch, can't tell if it is on or off by touch. Is it sitting on something else that is radiating heat like an amp or is it in the exhaust of your PC? My PC puts out a lot of heat. I moved my dacs/amps to the other side because of it. But if it is off, I'd think the heat source has to be external. Nothing else makes sense.

But I know the some others with a DAC1 have indicated that their unit gets quite warm & mine is very cool to the touch too (but only when on). I'm not sure why. Maybe the same is true for some hdp units.

 

[etnt]

Quote:

Originally Posted by AustinHorn /img/forum/go_quote.gif I've had mine going 24/7 for a week & it is cool to the touch, can't tell if it is on or off by touch. Is it sitting on something else that is radiating heat like an amp or is it in the exhaust of your PC. My PC puts out a lot of heat. I moved my dacs/amps to the other side because of it. But if it is off, I'd think the heat source has to be external. Nothing else makes sense. But I know the some others with a DAC1 have indicated that their unit gets quite warm & mine is very cool to the touch too (but only when on). I'm not sure why. Maybe the same is true for some hdp units.

It's on the desk between the LCD and the cans. It feels warm when I touch it after returning from a workday or early in the morning, so there shouldn't be other equipment transferring their heat to it. In contrast, an Icon sitting next to it feels cool to touch.

Perhaps Jason can chime in on this and if I should bring it back to the dealer for an exchange?

 

[jasonl]

Quote:

Originally Posted by etnt /img/forum/go_quote.gif It's on the desk between the LCD and the cans. It feels warm when I touch it after returning from a workday or early in the morning, so there shouldn't be other equipment transferring their heat to it. In contrast, an Icon sitting next to it feels cool to touch. Perhaps Jason can chime in on this and if I should bring it back to the dealer for an exchange?

Even with the Volume/On/Off knob in the OFF position, the HDP's
voltage regulator and the Class-A headphone amp is ON all the time, as
long as the power connector is plugged in. The USB DAC gets the
power from the host PC, so it could be warm from plugging into a PC
that's ON as well.

 

[HeadphoneAddict]

Right now my HDP is only slightly above room temperature when switched on but idling and not playing music. With playing music it barely gets much warmer, but I haven't paid a whole lot of attention to it at that point because the music was taking all my attention. The amp is very involving and engaging.

 

[charlesyu]

How does the HDP compare to the Benchmark DAC-1?

 

[etnt]

Jason, thanks for the clarification.

 

[jasonl]

Quote:

Originally Posted by charlesyu /img/forum/go_quote.gif How does the HDP compare to the Benchmark DAC-1?

If it is not better than DAC-1, I will make sure you get not only full refund of the HDP purchase price, but the shipping as well

 

[jasonl]

Quote:

Originally Posted by bcwang /img/forum/go_quote.gif AustinHorn, I don't think the bel canto link could possibly reduce hiss for my situation. The hiss I'm hearing is not from the source material, but is simply the noise floor of the HDP itself. I can hear it the amp off, and nothing connected to it except the power supply. HeadphoneAddict, I've tried the shure attenuator that comes with the headphones, and it seemed to dramatically decrease sound quality when I got it to the point of no hiss. Unless the shure one is much worse quality, I don't think the volume attenuator solution will work. For now, I can connect my tomahawk through the rca outputs if I need to use IEMs with it. But I haven't used IEMs in a while now so I haven't been too concerned with it.

See this very technical note about the noise floor. It is extremely low, not much we can do because HDP is optimized for headphones, not IEM.

Icon HDP Technical Note