[skidu]

Quote:

Originally Posted by drews /img/forum/go_quote.gif P.S. The HDP sounds really nice, better than the uDAC which I love...

If you could post some impressions on how it fairs with the HD650's that would be great, especially how it compares to the MKIII. I've been looking to get my first amp/dac for my HD650 and i really hope this fits the bill.

 

[bcwang]

I got to spend some time today at the nuforce office listening to multiple hdp units. By the way, those guys are really nice and helpful. To set the expectations straight...here are my findings.

-My HDP is the standard issue, nothing wrong with it other than the swapped channels. I already got that taken care of. Which kind of unfortunately means....

-The HDP does indeed hiss but the ability to detect it depends on the headphone and your hearing. And of course the more sensitive your hearing, the more likely you'll hear the hiss. But it seems like most people can't hear it (what a blessing for you guys!)

-The se530 hisses much more loudly than the westone um3x which I tried. But the um3x was still easy to detect the hiss. So far in my trials, the SE530 is THE headphone to detect hiss with. I don't know why the 124db/mw um3x hissed much less than the 119db/mw se530, maybe it has to do with the impedance being higher.

-I am able to hear the hiss with a couple of full size headphones as well, but I think most people could not. The level is much lower than when using IEMs and I could consider that acceptable for my use. Though I definitely cannot call it "pure blackness" in the background.

Now, to let this thing break-in so I fully appreciate the sound quality. So far it does sound very pleasant, but the hiss got me distracted the first few days. Now that I know my unit isn't defective, I'll try to really just enjoy it and see if it'll suit me.

 

[HeadphoneAddict]

Quote:

Originally Posted by bcwang /img/forum/go_quote.gif I got to spend some time today at the nuforce office listening to multiple hdp units. By the way, those guys are really nice and helpful. To set the expectations straight...here are my findings. -My HDP is the standard issue, nothing wrong with it other than the swapped channels. I already got that taken care of. Which kind of unfortunately means.... -The HDP does indeed hiss but the ability to detect it depends on the headphone and your hearing. And of course the more sensitive your hearing, the more likely you'll hear the hiss. But it seems like most people can't hear it (what a blessing for you guys!) -The se530 hisses much more loudly than the westone um3x which I tried. But the um3x was still easy to detect the hiss. So far in my trials, the SE530 is THE headphone to detect hiss with. I don't know why the 124db/mw um3x hissed much less than the 119db/mw se530, maybe it has to do with the impedance being higher. -I am able to hear the hiss with a couple of full size headphones as well, but I think most people could not. The level is much lower than when using IEMs and I could consider that acceptable for my use. Though I definitely cannot call it "pure blackness" in the background. Now, to let this thing break-in so I fully appreciate the sound quality. So far it does sound very pleasant, but the hiss got me distracted the first few days. Now that I know my unit isn't defective, I'll try to really just enjoy it and see if it'll suit me.

You can look forward to losing some of your bat-like hearing as you get older, but most people can't hear the levels of hiss that you can.

Compared to my ALO Amphora and AMP3 with IEM, the HDP is dead silent/black background. I can't hardly hear hiss on the ALO Amphora with most full size phones, so I can't imagine how it would be to hear hiss on the HDP with full size phones. You certainly have incredibly sensitive ears and not average ones.

 

[pekingduck]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif You can look forward to losing some of your bat-like hearing as you get older, but most people can't hear the levels of hiss that you can. Compared to my ALO Amphora and AMP3 with IEM, the HDP is dead silent/black background. I can't hardly hear hiss on the ALO Amphora with most full size phones, so I can't imagine how it would be to hear hiss on the HDP with full size phones. You certainly have incredibly sensitive ears and not average ones.

Hi Larry,
It's probably not a fair comparison... but I'd really like to ask if the amp part of the HDP rivals the Amphora?

 

[HeadphoneAddict]

Quote:

Originally Posted by pekingduck /img/forum/go_quote.gif Hi Larry, It's probably not a fair comparison... but I'd really like to ask if the amp part of the HDP rivals the Amphora?

No, but it's close. After just 100 hours the final rev HDP beats all my other portable DAC/amps, although the best ones come close to the HDP, just as the HDP comes close behind the Amphora (with either Pico DAC or HDP DAC as source). Once you get to a certain level of performance, the improvements in sound are often subtle, but sometimes more noticeable than others. The D4 with upgraded opamps can sound fantastic with my IEM, but I can switch to the HDP and feel like the sound is a little more refined and I can hear deeper into the music - yet it wont make the D4 sound bad, just not as good.

The differences in power, or hiss, or synergy with some pieces of gear will stand out more than the differences sound signature or soundstage. For example, the Amphora sounds good with HE-5 but it cannot match the power levels of the HDP with those phones, so that is one area where the HDP stands out above the Amphora. The Amphora does his with my ES3X and the HDP doesn't, plus it gives them a nice bump in the bass, so that is another area where the HDP excels over the Amphora.

I believe I like HDP just a little more than the 24/96 DACport and Apogee mini-DAC headphone out as well, which are also slightly better than the Pico and D4 and others. The depth and refinement I hear as the final revision HDP burns-in is taking it to another level over the 1st prototype I tested. Still, I think the DACport would be my next favorite next to the HDP, even over the Apogee headphone out (whether using 24/48 USB or 24/96 optical). It was my comparison of the DACport side by side with Pico amp w/DAC that convinced me the Pico could be sold (Pico's DAC is better than it's amp). Then again, I also liked the opamp rolled D4 more than the Pico amp w/DAC. The Pico DAC-only > Amphora or P-51 is another story, and it comes very close to the HDP, except in power - but that costs $900 including the jumbo cryo silver x mini IC ($800 with a cheap cable).

With the final rev HDP here since Thursday night I have been neglecting my main rig, bedroom rig, laptop rig, stat rig, and everything else as I continue to enjoy the HDP with all my IEM, HD600 and HE-5. I'm thinking these 100 hours of burn-in are enough to get an idea of what it can do, but I'm still going for my standard 300 hours for consistency.

 

[kostalex]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif It was my comparison of the DACport side by side with Pico amp w/DAC that convinced me the Pico could be sold (Pico's DAC is better than it's amp).

Do you mean USB > DACport > Headphones perform better than USB > Pico amp w/DAC > Headphones? Where may I find the details of this comparison? What headphones were used?

 

[syke]

You've got what it takes to be a golden ear...

in my workplace that is...

My colleagues are banging their heads trying to master the various frequencies with pink noises...


Quote:

Originally Posted by bcwang /img/forum/go_quote.gif I got to spend some time today at the nuforce office listening to multiple hdp units. By the way, those guys are really nice and helpful. To set the expectations straight...here are my findings. -My HDP is the standard issue, nothing wrong with it other than the swapped channels. I already got that taken care of. Which kind of unfortunately means.... -The HDP does indeed hiss but the ability to detect it depends on the headphone and your hearing. And of course the more sensitive your hearing, the more likely you'll hear the hiss. But it seems like most people can't hear it (what a blessing for you guys!) -The se530 hisses much more loudly than the westone um3x which I tried. But the um3x was still easy to detect the hiss. So far in my trials, the SE530 is THE headphone to detect hiss with. I don't know why the 124db/mw um3x hissed much less than the 119db/mw se530, maybe it has to do with the impedance being higher. -I am able to hear the hiss with a couple of full size headphones as well, but I think most people could not. The level is much lower than when using IEMs and I could consider that acceptable for my use. Though I definitely cannot call it "pure blackness" in the background. Now, to let this thing break-in so I fully appreciate the sound quality. So far it does sound very pleasant, but the hiss got me distracted the first few days. Now that I know my unit isn't defective, I'll try to really just enjoy it and see if it'll suit me.

 

[HeadphoneAddict]

Quote:

Originally Posted by kostalex /img/forum/go_quote.gif Do you mean USB > DACport > Headphones perform better than USB > Pico amp w/DAC > Headphones? Where may I find the details of this comparison? What headphones were used?

You have all the details I have written anywhere on that subject - it was my first post about it.

The DACport and HDP are set for 24/96 USB and I'm listening to Nancy Bryan "Neon Angel" in 24/96 hi-res download, and they both sound better to me via USB DAC than the Pico amp w/DAC. I switch to Diana Krall "Live in Paris" 16/44.1 CD rip and I still feel that way. The sound just seems more complete and present and natural, letting me hear deeper into the music - whether with Westone 2, Monster Turbine Pro Gold, Westone 3, Westone ES3X, UE11Pro or JH13Pro. In my previous reviews of the Pico amp I felt that it was slightly lacking in lower midrange warmth vs other amps, although detail, transparency and soundstage is great. With already warm phones like Denon, Ultrasone and some Grados or HD600 the Pico was good.

But, with a wide variety of other portable DAC/amps to pick from I usually preferred to use the Pico as a DAC/preamp feeding an already warm sounding amplifier (like Woo GES or Woo WA6). The Pico Slim vs Pico Amp at CanJam rectified all of my concerns about the original Pico sound, matching my P-51 in sheer portable performance, and possibly being a little more refined sounding while doing it (at least with my ES3X). Since I have the Pico DAC-only it made sense to sell the original Pico and add the Slim. This way I can separate the DAC and amp and have a smaller amp to take with me for iPod, and leave the DAC portion with the Macbook.

The HDP target audience is different than the DACport or Pico amp w/DAC target audience - since HDP plugs into the wall and has more power for full size phones. But, it still handles all my IEM with finesse. If I wanted the best portable DAC/amp that could run entirely off USB power for mobile laptop use, I'd pick the DACport over the other portable DAC/amps I have reviewed (including Duet, Pico, and all the others). It's also a little more powerful than the uDAC with HD600. If I wanted the best bang-for-the-buck USB DAC/amp that could plug into the wall, to feed full size amps and drive full size phones, it would be the HDP. The Apogee mini-DAC headphone out comes close, but it's not quite as refined and sounds a little more aggressive like a P-51, and the mini-DAC headphone soundstage is not as deep although it is very wide. Others have complained about the mini-DAC's built-in amp sounding more 2D than others too. And, I got one of the last USB versions of Apogee, as they are all now firewire.

Hopefully sometime this week or the next I will try comparing the HDP vs Apogee mini-DAC while feeding the full size amps in my bedroom, like the WA6, SAC KH1000, and ALO Amphora. I'll be able to switch between the external amp and built-in amp as well. Then I plan to take the HDP downstairs to my main rig to compare to the PS Audio Digital Link III feeding my EC ZDT amp. I can use my Jensen balanced input transformers to feed the HDP into my balanced WES (no SE inputs). And, as a bonus I can feed my phono preamp into the HDP, not just digital. A final bonus is I can also try my 12v Sigma 11 PSU that I use for the Apogee and see if that helps performance.

 

[AustinHorn]

I just got my HDP in the mail today & now have it running now. After reading bcwang's comments I decided to test it for hiss too. I turned the volume up all the way & tried all my head & earphones with it. At full volume I was able to detect a hiss on my E Hf5 earphones. On my unit off is about 10 o'clock & full-volume is about 7 o'clock. On those headphones I hear nothing until about 6 then I hear a little static & from 6-7 I hear a low hiss. However with these ear phones, even with loud rock, normal listening volumes would be between 2-3 o'clock. On my UE triplefi10vis, I get no hiss but do hear the static at 6 when moving the dial. Now on my full size phones there is zero hiss or static & that includes my HD 650s, K 702s, ER325is, & Ultrasone HFI 700s. I'm 60+ and though I do test as having excellent hearing for my age, I know I've never had "bat-like" hearing (too much loud rock back in the 60s). But the bottom-line is that at least on my unit, hiss isn't something to worry about, but with the right earplug (ie He5), it is there. I've connected it to my PC using USB (the hiss louder) & via the coax/bnc from my Bel Canto Link (hiss is much less), but it is still there. Anyway, FYI.

Soundwise, with no burn in, IMHO it is a good step up from my modded Zero, my udac, & my SuperPro707 dacs, but still a good step down from my completely burned in & highly modded Benchmark DAC. I'm hoping/expecting that gap will shrink considerably over the next 300 hours or so though. Fingers crossed.

Anyway, for anyone considering this amp/dac, and assuming my unit is typical of the full production line, I don't think hiss is a big issue & that the price performance ratio is very, very good.

Now I guess I'll wait and see what/when Jasonl & Co. decides to have these units returned for repair &/or replacement plus that 20% refund (a great deal gets even better, thanks Jasonl). My guess is that they'll just have us return these units & replace them with new units from the factory but JIC I'll continue with the burn in process!

 

[HeadphoneAddict]

Quote:

Originally Posted by AustinHorn /img/forum/go_quote.gif I just got my HDP in the mail today & now have it running now. After reading bcwang's comments I decided to test it for hiss too. I turned the volume up all the way & tried all my head & earphones with it. At full volume I was able to detect a hiss on my E Hf5 earphones. On my unit off is about 10 o'clock & full-volume is about 7 o'clock. On those headphones I hear nothing until about 6 then I hear a little static & from 6-7 I hear a low hiss. However with these ear phones, even with loud rock, normal listening volumes would be between 2-3 o'clock. On my UE triplefi10vis, I get no hiss but do hear the static at 6 when moving the dial. Now on my full size phones there is zero hiss or static & that includes my HD 650s, K 702s, ER325is, & Ultrasone HFI 700s. I'm 60+ and though I do test as having excellent hearing for my age, I know I've never had "bat-like" hearing (too much loud rock back in the 60s). But the bottom-line is that at least on my unit, hiss isn't something to worry about, but with the right earplug (ie He5), it is there. I've connected it to my PC using USB (the hiss louder) & via the coax/bnc from my Bel Canto Link (hiss is much less), but it is still there. Anyway, FYI. Soundwise, with no burn in, IMHO it is a good step up from my modded Zero, my udac, & my SuperPro707 dacs, but still a good step down from my completely burned in & highly modded Benchmark DAC. I'm hoping/expecting that gap will shrink considerably over the next 300 hours or so though. Fingers crossed. Anyway, for anyone considering this amp/dac, and assuming my unit is typical of the full production line, I don't think hiss is a big issue & that the price performance ratio is very, very good. Now I guess I'll wait and see what/when Jasonl & Co. decides to have these units returned for repair &/or replacement plus that 20% refund (a great deal gets even better, thanks Jasonl). My guess is that they'll just have us return these units & replace them with new units from the factory but JIC I'll continue with the burn in process!

At the 2-3 o'clock which is where you would listen, I am willing to bet the headphone amp is very quiet with IEM. Mine is. I mentioned that if I crank to near max, with no music I can hear a little hiss with IEM, but I would NEVER have the knob up there with IEM without going deaf.

The HDP headphone amp does sound a little rough at first, but it really improves over the first 100-150 hours. I think you will be happy once you get past that point.

As for sending it back for swapping the channels on 3.5 mm input, I was thinking that they will change it on your actual unit and send the same one back.

 

[bcwang]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif At the 2-3 o'clock which is where you would listen, I am willing to bet the headphone amp is very quiet with IEM. Mine is. I mentioned that if I crank to near max, with no music I can hear a little hiss with IEM, but I would NEVER have the knob up there with IEM without going deaf. The HDP headphone amp does sound a little rough at first, but it really improves over the first 100-150 hours. I think you will be happy once you get past that point. As for sending it back for swapping the channels on 3.5 mm input, I was thinking that they will change it on your actual unit and send the same one back.

Haha, I always have to convert volume knob positions as everyone seems to be using the HDP in a different orientation. I myself use it in the standing up (in the stand) position where all letters and words are right side up. Off is 7 o'clock and full volume is 5 o'clock.

AustinHorn, what you call detecting hiss when the volume is at 3 o'clock (your 6 o'clock) is not what I would consider real hiss as that volume is near full scale and would blow the HF5 if any real music was playing. If you can't detect any background noise at your actual listening volume, I'd call that a quiet amp. Turning any amp to full volume I can hear hiss out of every single headphone amp I've tried using any headphone I've ever tried. That is just not really having hiss. Having a problem with hiss is really only when you can hear the hiss in the quiet parts of your music. You, AustinHorn, are lucky that you can't hear the hiss I'm mentioning, even though you think you can!

And Larry is right, they will take the unit you send back, perform the fix, and send it back to you. Some of you will be lucky and get the fixed units as they were able to recall some of the shipments back and perform the fix before re-shipping. Others will get it sooner but will have to ship back for the fix.

 

[AustinHorn]

Oh, bcwang, I'm very glad not to have the problems you've had. And I do realize that it has a very black background at my 2-3 position but I was just pointing out that there is a hiss on the Hf5 when turned up all the way (no music playing). My Benchmark is dead quite at that level w/o music playing so that was what I was using that as my benchmark to compare the HDP against! The udac has even more hiss too when I tune it up like that. Now with my 702, I have to turn my HDP up to my 6 o'clock + position to play at the levels I like, but pausing the music still leaves a very black background with them so I'm very satisfied, hisswise. I had expected a little more headroom than that with my K702s, but I think it will be fine, especially if I use it primarily as a dac feeding my Doge or LDV amps. It drives all my other headphones just fine with room to spare but I tend to favor my AKGs for most of the stuff I listen to. I figure I'll free up the Benchmark from the PC duties so I can put it back with my stereo setup which is what I really had in mind for it in the long run.

Believe me, regarding my 1st post above, I wasn't not complaining. I'm looking forward to getting the break-in that Larry was talking about to see the improvement. Thanks to you guys, I now know that I will get my own unit back so I'll leave it burning in with a burnin disk until I get the return shipping label. I'm just very happy my HDP doesn't have the problem you (bcwang) experienced.

I heard from Nuforce support this evening so I'm guessing since I formally accepted their offer I should have the return shipping label by the weekend or Monday. I assume this will go back to Calif. rather than China, right? I hope so. Anyway, it is good to know that the time I'm putting on the unit won't be a waste. I'll run it 24/7 until it is time to pack it for return shipping.

Thanks for the feedback guys. I'm happy I get to keep this unit. I wouldn't have even returned it if it wasn't for the 20% rebate Jasonl is kindly offering. My old RWA amps had reversed inputs too, but once known, it wasn't really an issue. I just relabled them, hooked them up appropriately & it worked fine. I assume this would work fine too unless someone knows something I don't with this problem. Anyway, I'm very glad to hear that I can expect considerable experience in the 1st 100-150 hours. I'm looking forward to it. On most of my gear I don't consider it "finished" until after 400 hours. My 702s certainly continued to change after 300 & so did several of my amps/dacs/cables.

 

[bcwang]

Quote:

Originally Posted by AustinHorn /img/forum/go_quote.gif I'm just very happy my HDP doesn't have the problem you (bcwang) experienced.

To clarify, it was not my HDP that had the problem (as confirmed by me testing out 2 other units), but my ears that have the problem with picking up hiss. I just need to use lower sensitivity headphones and I'm fine.

And yes, the repair work is done in their office in California. In this case, the swapped channels being on the 3.5mm is much less tolerable than swapped RCA jacks...well for obvious reasons being you can't simply just swap cable positions like in the RCA scenario since it's a single cable.

AustinHorn, it'll be really interesting to hear your comparison of the HDP to the DAC1 once you've fully broken it in. I've always considered one in the back of my mind, but never could commit to buying one. If the HDP turns out favorable then I can relax that thought...

 

[AustinHorn]

Regarding the hiss issue I stand corrected. As was said earlier, I think by you, in this case, your bat-like hearing may not be an advantage. But being limited to just K702s (my favorite full-size headphone & I've tried them all at one time or another) things are not all bad.

Re: the 3.5"/RCA cable swap issue, again I did understand & you 're right, I was comparing apples to oranges in this case & I do want that problem fixed.

Re: the DAC1, it has been a while since my DAC1 was stock, so I don't know if even with your hearing you'd be able to detect any his, I doubt it, but even stock it is close to my favorite dac ever. But with the overhaul done on mine by Reflection Audio, this baby sings. Of couse the modding cost almost as much as the dac, but IMHO it is well worth it. Especially with my current stereo setup.

Opps, I've got to go. We just had a plane hit an office building here in Austin. NOT GOOD!

 

[Fantoon]

Quote:

Originally Posted by AustinHorn /img/forum/go_quote.gif Oh, bcwang, I'm very glad not to have the problems you've had. And I do realize that it has a very black background at my 2-3 position but I was just pointing out that there is a hiss on the Hf5 when turned up all the way (no music playing). My Benchmark is dead quite at that level w/o music playing so that was what I was using that as my benchmark to compare the HDP against! The udac has even more hiss too when I tune it up like that. Now with my 702, I have to turn my HDP up to my 6 o'clock + position to play at the levels I like, but pausing the music still leaves a very black background with them so I'm very satisfied, hisswise. I had expected a little more headroom than that with my K702s, but I think it will be fine, especially if I use it primarily as a dac feeding my Doge or LDV amps. It drives all my other headphones just fine with room to spare but I tend to favor my AKGs for most of the stuff I listen to. I figure I'll free up the Benchmark from the PC duties so I can put it back with my stereo setup which is what I really had in mind for it in the long run. Believe me, regarding my 1st post above, I wasn't not complaining. I'm looking forward to getting the break-in that Larry was talking about to see the improvement. Thanks to you guys, I now know that I will get my own unit back so I'll leave it burning in with a burnin disk until I get the return shipping label. I'm just very happy my HDP doesn't have the problem you (bcwang) experienced. I heard from Nuforce support this evening so I'm guessing since I formally accepted their offer I should have the return shipping label by the weekend or Monday. I assume this will go back to Calif. rather than China, right? I hope so. Anyway, it is good to know that the time I'm putting on the unit won't be a waste. I'll run it 24/7 until it is time to pack it for return shipping. Thanks for the feedback guys. I'm happy I get to keep this unit. I wouldn't have even returned it if it wasn't for the 20% rebate Jasonl is kindly offering. My old RWA amps had reversed inputs too, but once known, it wasn't really an issue. I just relabled them, hooked them up appropriately & it worked fine. I assume this would work fine too unless someone knows something I don't with this problem. Anyway, I'm very glad to hear that I can expect considerable experience in the 1st 100-150 hours. I'm looking forward to it. On most of my gear I don't consider it "finished" until after 400 hours. My 702s certainly continued to change after 300 & so did several of my amps/dacs/cables.

How does the amp section compared to the LD MKV?