After some research on the Rockbox forums, I decided to start looking at the code to see what the limitations were on the digital output.  This lead to me wonder, just how many people are using an H1x0 player as their source, using the digital output?  The Rockbox developers think there aren't many of us.  I'd like to give them a better number.  
 
To make things more interesting, what DAC/amp/headphone combination do you use with your H1x0?  I'm using an iBasso D1 (with HiFlight's TopKit opamps) and Denon AH-D2000 with JMoney pads.  Wonderful combo!
 
As a side note for the curious, I can confirm that ALL output going through Rockbox gets converted to redbook (16-bit 44.1kHz).  Files already in 16/44 are not resampled, though.  I can't guarantee being able to change this, but given that my H120 is my primary source (my laptop has WAY too much jitter from the spdif port), I'm hoping i might be able to hack it a little to squeeze just a little more out of it.  If anyone knows of a way of measuring bit depth and sample rate coming out of an spdif port, please let me know.  EDIT: Did some tinkering and hoooo boy would it be a challenge to try to even allow 48kHz native playback.  As the developers stated, a LOT of other code makes assumptions about sample rate being 44.1kHz, so upping the sample rate just makes everything play slowly.  Changing the speed conditionally on the sample rate would be nasty.  The bit depth is even more of an unknown.  So yeah, it is recommended that all files be transcoded to redbook with a better dithering software before use with Rockbox.

My configs: Rockboxed iHP-120's digital out + iBasso D10 or Vulcan or Vulcan VB or HeadRoom Portable Micro Amp with DAC

I am using rockboxed iriver with a Swiss-made portable professional DAC\amp called Sonosax SX-DA2. That feeds Ultrasone Ed8 (recabled)

Rockboxed iRiver iHP-120, optical-out to an iBasso D10 to a pair of Westone UM3X earphones. This setup has kept me happy for quite some time now.

Couple Questions:
 
Which Sounds better Iriver H140 or H120?
 
is the rtc chip really necessary?
 
Do they have a Neutral Sound Sig, how to they compare to ipods and the zunehd?
 
Why do people optical connect the h120 to the H140 then to an Amp, wouldn't it sound better just to hook the h140 straight to the DAC?
 
Whats the largest capacity: Battery and Hard Drive for the h1xx series?
 
Can you replace the HD with a CF Card, does it improve sound? are all cf card capacities supported?
 
How much all together should a battery/hd/real time clock chip mod cost?
 
Can either player index/sort flac files?

The current digital output is definitely far from perfect with the iRiver H1x0 series.  It's fun to use in a pinch, but I've moved on long ago.
 
-Ed

i dont like the sound of ibasso D10, but there are not much option for portable amp with digital input

Which Sounds better Iriver H140 or H120?  
is the rtc chip really necessary?
 
Do they have a Neutral Sound Sig, how to they compare to ipods and the zunehd?
 
Why do people optical connect the h120 to the H140 then to an Amp, wouldn't it sound better just to hook the h140 straight to the DAC?
 
Whats the largest capacity: Battery and Hard Drive for the h1xx series?
 
Can you replace the HD with a CF Card, does it improve sound? are all cf card capacities supported?

Click to expand...

None of them sound better. They are both absolutely not interesting in terms of sound auqlity. Using them as an analogue source is senseless, it is just as good as most other consumer MP3 players out there. For the same reason, feeding difital from h120 to h140 and then to amp is pretty senseless, get a good quality external DAC\amp and you will be rewarded.
 
RTC chip is not needed, you have clock in your cellular, that's enough
 
There is no need to compare irivers to ipods and zunes, they are all just average sounding mp3 players. The ONLY way to use iriver is as a purely digital transport feeding good dac\amp.
 
I am using 120 gb hdd and 2200 mah Cameron Sino battery, works great for me Dunno about using larger hard drives.
 
You can replace hdd with cf, it will somewhat improve battery life but not sound quality. Forget about SOUND of h1x0 series, it is nothing special and there is nothing to improve there.
 
Quote:

edwood said:

The current digital output is definitely far from perfect with the iRiver H1x0 series. It's fun to use in a pinch, but I've moved on long ago.

Click to expand...

Optical in irivers is not very good, that's true. However, you can mod h1x0 to have a coax spdif output (actually there is a coax out pad on the PCB, all you need is to rewire it to one of the jacks), and that will somewhat improve things. As well, if you use a good DAC with good jitter handling and good coax cable, you will get pretty good sound. There is no alternative to h1x0 as a portable digital source.

In my opinion, the analog line out on the h100 and h300 series players is extremely good. I'd use optical if I had a dac here, but alas I don't.

 
Quote:

abyrvalg said:

Optical in irivers is not very good, that's true. However, you can mod h1x0 to have a coax spdif output (actually there is a coax out pad on the PCB, all you need is to rewire it to one of the jacks), and that will somewhat improve things. As well, if you use a good DAC with good jitter handling and good coax cable, you will get pretty good sound. There is no alternative to h1x0 as a portable digital source.

Click to expand...

Do you have a pic of where this is on the board? I would like to mod one of my 120s.

I use my iriver iHp120 as a transport for my home/digital system.
 
Iriver
 
Behringer SRC2496
Behringer DEQ2496
 
Amp
 
The only mod I would like to see to the optical output (perhaps it extends to the whole player, and has been addressed since I last upgraded my rockbox) is the ability to output 24/96.

wuwhere said:

Do you have a pic of where this is on the board? I would like to mod one of my 120s.

Click to expand...

 
Well, the spdif out pad is clearly marked on the PCB, it is right near the optical out socket (see here). It is marked as SPDIF_TX - all you need is to tap to it and to the iriver's ground plane. However, when you do it, your optical out will not work, so what I did is I removed optical out LED at all, and rewired SPDIF to analog out socket. Now I use an ordinary 3.5 mm jack for spdif.
 
On this picture you can see it too. It is the pad near the left lower corner or the leftmost white socket (the one marked with a red pen).

Quote:

abyrvalg said:

 
Well, the spdif out pad is clearly marked on the PCB, it is right near the optical out socket (see here). It is marked as SPDIF_TX - all you need is to tap to it and to the iriver's ground plane. However, when you do it, your optical out will not work, so what I did is I removed optical out LED at all, and rewired SPDIF to analog out socket. Now I use an ordinary 3.5 mm jack for spdif.
 
On this picture you can see it too. It is the pad near the left lower corner or the leftmost white socket (the one marked with a red pen).

Click to expand...

Thanks.

I do, 
 
and I think it sounds fine. Much finer with the D10 and a opamp kit using TLE2141, and the EL8201 buffers! That combo allows for clean optical transport into the amp, and then the music rocks out in the Amp stage with the Topkit. It comes out of the amp sounding bassier than anything I've put in the D10 and definitely nicer than the Headphone Out on the iRiver H1xx. 
 
I'd say this combo of opamps takes the D10 to potential.
 

The voicing and instrument seperation in those buffers is Great, but the microdynamics in TLE2141 amp is stellar!

 

 

EDIT: 

 

 

Well Folks, I don’t know about you, but I’ve been living with my iRiver H120 & H140 and iBasso D10 for years.

I just upgraded to HiFlight’s v.3 Topkit for the iBasso D10 consisting of an adaptor for the LR amp socket, a custom, Class A Biased TLE2141 opamps in a dual mono module if i guess at the config right from the way it looks, and the nice EL8201 opamp buffers.

voicing, dnamism, and realism are enhanced with this… not that the D10 with its excellent Standard Topkit or choices for opamp rolling was a slouch for starters.

I used to prefer the elastic bass-to-stretchy-treble signature of the LMH6643 in the LR, with the AD8656 as BUFFERS, but now I’m in nirvana, as everything is sounding studio accurate and organic, and I primarily listen to Electronic.

Using a stock firmware H140 to feed a MicroDAC/D10 for an SR71 and RS-1's, HF-2's, UE5c's, or PK-1's. 
 
The optical out has been (long ago) demonstrated as bit perfect for regular redbook audio.  It's a fine portable source and I've had no complaints even as compared to some pricier setups.  I've moved away from Rockbox as I don't currently need the extra features...and the 1.66 firmware has been ridiculously stable for me over the years.