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DAP with the best sound quality using Rockbox and IEMs?

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Christine Tham:

--- Quote from: Llorean on February 28, 2008, 03:40:21 PM ---I hate to be pedantic here, but while trying to describe an objective issue, you've been very subjective in what jitter results in. As well. jitter in CD reading is often an issue with the actual reading. What phase are you particularly concerned with jitter in, communication with the DAC?

All you've done is basically said "jitter makes it sound bad." Where, exactly, would jitter occur on an MP3 player, and how much, exactly, is the maximum it could reasonably be expected to affect output in hard terms?

--- End quote ---

Well, I would encourage you to actually do some reading if you are interested in learning more about jitter. Google for Julian Dunn and jitter, and you will find a few papers published by him.

The reason I am describing jitter in subjective terms is because it is not easily measurable, unless you have expensive equipment or do manual calculations based on J-test outputs. What I describe is based on my experience. I have reviewed dozens of DVD players, including high end ones costing $10-15,000. I have attempted to measure jitter on them. I have even built and designed my own player.

By the way, jitter does not always make things sound "bad." There have been reports of people who find high jitter euphonic. Our ears are incredibly adaptive, and it's easy to get used to a particular sound, even when it's not accurate.

Jitter can occur anywhere in the playback chain. Yes, there is jitter in the pits encoded on a CD, but this is typically removed through a memory buffer on the optical transport itself.

Jitter on mp3 players can occur in a number of ways (including RFI generated by the processor). But the most probable cause is logic induced modulation on the playback chain, given that you have a combination of a fairly powerful CPU in close proximity to the DAC, and an relatively low current power source.

ZincAlloy:

--- Quote from: Llorean on February 28, 2008, 03:22:42 PM ---Are you asking anything? I've already said you won't hear it with those.

--- End quote ---

no, just adding data to compare. I know I can't hear the hiss with them  ;D

markun:

--- Quote from: ZincAlloy on February 28, 2008, 12:35:18 PM ---hiss? what hiss? my h300 isn't hissy at all.

--- End quote ---

--- Quote from: ZincAlloy on February 28, 2008, 12:46:41 PM ---I use Koss Porta Pro headphones.

--- End quote ---

I also don't hear the hiss with my Porta Pro's, but I do hear it with my Sennheiser CX300's.

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