[HiFlight]

Quote:

Originally Posted by dnewhous /img/forum/go_quote.gif Putting a class A amplifier on a portable audio device is a dumb idea. I'll be impressed when someone puts a Universal Class D amplifier on a PMP.

The advantage of a Class D is the efficiency of operation, not improved sound quality. Class A bias is noted for achieving the very best audio quality at the expense of efficiency. Considering the aready very long battery life exhibited by the AMP3, I can see little, if any, advantage by Hisoundaudio attempting to change to a Class D circuit.

 

[Chef]

I actually appreciate the discussion of concerns about the class a amp inside the AMP3. I don't think these threads should be 100% positives and just saying how much you love it... that's not useful. It actually is interesting to think about just how exactly they're working around it, and what they might have sacrificed to do it. It's clearly not an ordinary application, so skepticism (and calm, factual explanations to quell that skepticism) are absolutely necessary for the intelligent buyer and curious owner. No silliness about "I know what I hear."

Since the power source of a lithium battery is obviously a lot weaker than a wall outlet for a typical class A amp, what impacts does that really have? You're not trying to power full blown speakers, of course, but I pretty much use my beast of a amp near full volume for my headphones. I wonder how the Amp3 really scales up.

 

[tstarn06]

"Concerns" are the same as saying it's a "dumb idea?" Not sure if that's what you are saying, but if so, doesn't sound like a very useful approach to addressing any concerns. It's certainly not a way to impart constructive skepticism. Sure, discussions are good, but what's wrong with someone saying what they hear is better than anything else they've heard? Just curious.

 

[foreverfi]

Quote:

Originally Posted by Punnisher /img/forum/go_quote.gif Thanks for the review. We need someone to do a RMAA test to see how the Amp3 handles low frequencies at various impedances. Bass rolloff is a common problem with daps and I'd like to know how the Amp3 performs.

I don't think the RMAA test has too much reference for the sound quality. Every body know that the IPOD have a very good RMAA chart with very flat frequencies responsive curve. But IPOD is not the best one in term of sound quality.

My personal opinion is ear is the best test tool for a audio gears because machine has never listened to numerous albums.

Maybe to normal player, RMAA test have will be enough, but to the hi end device, our hearing audient is more important.

Of course it's my humble opinions, you can keep your opinions.

 

[Jupiterknight]

What are users of the AMP3 experience with mp3 compressions format with the AMP3 or what sounds the best/convenient for you? I have been trying different compression types and at the moment I leaning towards Lame CBR 224, I started out with Lame VBR -2, I know the differences should be extremely subtle between those two, but now to me it seems like the CBR sounded slighly better and had fewer glitches than the VBR settings.
I would very much like to hear what other AMP3 owners uses for mp3 compressions type and have good experiences with listening to. I'm just curious..

 

[Punnisher]

Quote:

Originally Posted by foreverfi /img/forum/go_quote.gif I don't think the RMAA test has too much reference for the sound quality. Every body know that the IPOD have a very good RMAA chart with very flat frequencies responsive curve. But IPOD is not the best one in term of sound quality. My personal opinion is ear is the best test tool for a audio gears because machine has never listened to numerous albums. Maybe to normal player, RMAA test have will be enough, but to the hi end device, our hearing audient is more important. Of course it's my humble opinions, you can keep your opinions.

I agree and did not intend to imply that measurements are everything. They are not everything.

Though I would be bothered if there was a strong rolloff with lower impedance headphones. I don't suspect it will because of the topology of the amplifier but it would be nice (and a strong selling point) if it were tested and documented.

Example: The D2 has an enormous rolloff problem with anything less than around 80ohms. People still swear it sounds fantastic. However for me, the rolloff is very noticeable hence why I don't use it much anymore. A piece of the audio spectrum is missing and I can't ignore that.

 

[tstarn06]

Quote:

Originally Posted by Jupiterknight /img/forum/go_quote.gif What are users of the AMP3 experience with mp3 compressions format with the AMP3 or what sounds the best/convenient for you? I have been trying different compression types and at the moment I leaning towards Lame CBR 224, I started out with Lame VBR -2, I know the differences should be extremely subtle between those two, but now to me it seems like the CBR sounded slighly better and had fewer glitches than the VBR settings. I would very much like to hear what other AMP3 owners uses for mp3 compressions type and have good experiences with listening to. I'm just curious..

Many of my tracks on the Amp3 are simply downloaded tracks, at 192k MP3 or WMA, so no ripping involved, and they sound excellent to me. I do have some 256 and 320 CBR rips, but you may or may not know that, according to early reports, the Amp3 is optimized to play 192k files.

 

[Jupiterknight]

Quote:

Originally Posted by tstarn06 /img/forum/go_quote.gif Many of my tracks on the Amp3 are simply downloaded tracks, at 192k MP3 or WMA, so no ripping involved, and they sound excellent to me. I do have some 256 and 320 CBR rips, but you may or may not know that, according to early reports, the Amp3 is optimized to play 192k files.

Thanks for your reply, yes I do remember reading about that he Amp3 is optimized to play 192 files and I def. tend to agree on that, but have just noticed that the CBR rips I recently have been "experimenting" with seems to function better with the D/A converter or amp and they tend to sound slightly better ( in terms of a better balance between highs, lows and depth) than the around same size VBR rips I have been using, or at least different to my ears.....
I rip from flac files using latest dbpoweramp. So I just wonder does the Amp3 do better with certain rip formats than other?

 

[average_joe]

Quote:

Originally Posted by Jupiterknight /img/forum/go_quote.gif What are users of the AMP3 experience with mp3 compressions format with the AMP3 or what sounds the best/convenient for you? I have been trying different compression types and at the moment I leaning towards Lame CBR 224, I started out with Lame VBR -2, I know the differences should be extremely subtle between those two, but now to me it seems like the CBR sounded slighly better and had fewer glitches than the VBR settings. I would very much like to hear what other AMP3 owners uses for mp3 compressions type and have good experiences with listening to. I'm just curious..

Quote:

Originally Posted by tstarn06 /img/forum/go_quote.gif Many of my tracks on the Amp3 are simply downloaded tracks, at 192k MP3 or WMA, so no ripping involved, and they sound excellent to me. I do have some 256 and 320 CBR rips, but you may or may not know that, according to early reports, the Amp3 is optimized to play 192k files.

On a FLAC vs. MP3 note (192K); I have done some A/Bing and FLAC does indeed sound better than 192K on the AMP3.

There is no way for me to quantify how much as a large amount to me (with my equipment and ears) might be a small amount to you, but it is a big enough difference to me that I want to have FLAC files.

If/when I get a chance I will test 320K vs. 192K vs. FLAC.

 

[Jupiterknight]

Quote:

Originally Posted by average_joe /img/forum/go_quote.gif On a FLAC vs. MP3 note (192K); I have done some A/Bing and FLAC does indeed sound better than 192K on the AMP3. There is no way for me to quantify how much as a large amount to me (with my equipment and ears) might be a small amount to you, but it is a big enough difference to me that I want to have FLAC files. If/when I get a chance I will test 320K vs. 192K vs. FLAC.

I hope you will have the time to do a test, I would really like to hear or read your opinion on this, so far I do hear a certain difference between the 320 and around 192k, but to my ears the sound of Amp3 probably have not settled completely yet to, or what types of compression or lossless sounds the best with my ears. I would just like opinions so it can help me reduce some of the time I spend on testing different formats or earphones/headphones for that matter!!

 

[tstarn06]

I may do some comparison listening too, just because I am curious about it now. I am using the Amp3 mainly just with onboard memory, so swapping out files is pretty easy.

 

[ulsanman]

I have found very little difference between 320 and 192 but a noticeable difference with flac which sounds fuller clearer and brighter.

 

[average_joe]

The differences I noted between FLAC and 192K was clarity, detail, and space. 192K sounded a little smeared and duller. I wouldn't say the FLAC files were brighter, but clearer, yes.

Edit: With more listening, and adding 320K to the mix (and one 320K WMA file), the biggest difference is the 3D space. Also, 320K and FLAC are much closer than 192K, at least as far as the treble. And each song is a little different. The one track I tested with WMA, Leona Lewis - A Moment Like This, wasn't a good choice, as the beginning of the song (which is what I use to A/B as it is easy to repeat that part by just skipping back/forward). I could detect no difference in the first 15 seconds, and then minimal differences in the part from 16 to 20 seconds. I could not tell a difference between the WMA and FLAC, and not too sure I could tell a difference between the 320K MP3. There was a difference to me between the 192K and everything else in the 3D space of the effects of her voice.

With ATB (3 songs, Justify, Desperate Religion, and Made of Glass) I could tell a difference in the space between all 3, as well as details the space revealed. I chose those as the songs have excellent space to start with.

I also listened to more artists/tracks with the similar results. I used the Mingo WM2 (using an impedance adapter to eliminate the hiss completely) for tonight's tests, but have verified this in the past with my Fuze and the IE8 and earlier with the AMP3 and the C710.

 

[a_tumiwa]

yes, i feel that the flac is clearer especially in high frequency then 192k bitrate. From my comparing between amp3 vs sony x1000, Amp3 is more forgiving to low bitrate than sony x1000

 

[TaoZar]

The AMP3 sounds great.

Is there a way to get it to germany? I really really want it!