[johnnylexus]

Quote:

Originally Posted by StevieDvd Many people find it hard to accept until they themselves hear a difference between docks,cables,sources etc. Remaining a sceptic is fine but believing everyone is fooling themselves that there is a difference is a bit conceited, as is the opinion that if you cant hear a difference then you have bad ears! It's just practise and familiarity with equipment and music that eventually brings it out. Or is it ...................

I'm not trying to sound conceited. One really cool thing I noticed when I went from Superfi 5.pro to the Shure e5c's was all of a sudden I could pick out the instruments in the soundfield, it was soooo cool.

I'm just trying to figure out if using the line out/amp combo will yield a similar boost in sonic performance. The cost is quite high in terms of portability, extra cables, etc.

 

[Jahn]

honestly, i really wouldn't run a headphone out vs. turbodock comparo straight into a can. could be bad for the can to plug right into a line out, as mentioned before. instead, get a mini to mini cable and input that into an external amp and plug your can into that. as mentioned before, make certain the volumes are even (lower the headphone out internal vol to 90%) otherwise the headphone out might sound "better" because it will be louder - that's just how our ears work.

if you set everything up like that to even the playing field, you will hear a definitely difference between your headphone out and your line out. honestly, on the go/portably you probably don't NEED to use a line out and a portable amp and the rest, but if you do use it, you will hear an improvement, even with all the ambient noise and walking around and stuff.

 

[StevieDvd]

Sorry johnnylexus was not implying you were conceited was speaking more generically, apolgies if it came out wrong.

Using a little logic for once I'd say that Apple would not have put a lineout on the Ipod if the headphone was the same at a set volume. All that would have been needed would be a button to autoset the volume (i.e lineout mode). Far cheaper than the extra hardware built in.

Bear in mind that the effect of the lineout is probably more apparent when you throw better headphones & amps at it as well so those of us pampering to our portable equipment are squeezing at much quality as we can from it - certainly not what most folk would call value for money though.

 

[greenleaves]

To those who hear the SQ difference, it will be helpful to look into how Apple designed the line-out and headphone out in the 5G.

Below is part of the DAC WM8983 signal path diagram referenced by the Rockbox developers. It has appeared to be identical to the speicifc CODEC used in 5G. You will see both the line-out (LOUT2/ROUT2) and the headphone out (LOUT1/ROUT1) are all branched out from the same signal paths out of the CODEC.

All D/A conversion and amplication are handled by the CODEC. The output signals are then shared by the headphone and the line-out. Apple simply fixes the line-out at 0dB, and EQ remains functional in both.

This fact confirms my experience with no SQ difference in the headphone out and the line-out. I would imagine for those who can hear the difference, they must have very sensitive ears or perhaps due to other reasons.

Here is the datasheet if you want more details about the CODEC.

http://www.wolfsonmicro.com/uploads/.../en/WM8983.pdf

 

[forsberg]

Quote:

Originally Posted by greenleaves This fact confirms my experience with no SQ difference in the headphone out and the line-out. I would imagine for those who can hear the difference, they must have very sensitive ears or perhaps due to other reasons.

So that means for ipod 5G the turbodock is pointless right? amping thru headphone out vs. turbodock is exactly the same....?

 

[forsberg]

... and if any SQ diff ppl hear on the 5g's - it'd just be the placebo effect?

 

[greenleaves]

I don't have a Turbodock, and so can't comment on it. I have used Sik ram din for awhile but no longer now. It's more convenient for me to use the headphone out instead, and save the port for other things such as an external battery charger etc..

Music listening always fills with subjective interpretations and emotional atachments to the music you are listening and the gears that you are using. It's all very personal. In the end it's the musical experience you get from it really matters!

The SQ comparison is part of a quest that satisifes my curiousity out of my muscial experience with the iPOD. It's a fun and revealing exercise after all.

 

[BavariaBarbarian]

Quote:

Originally Posted by greenleaves This fact confirms my experience with no SQ difference in the headphone out and the line-out.

That diagram is very informative and it does prove that the headphone output doesn't go through a separate amplification stage (as some have said).

But it does not prove that there can't be any differences between the hp-out and the line-out. The signal routing and the decoupling caps may and probably are different and who knows what else apple puts in the signal path...

Now don't get me wrong, I'm not saying that ther MUST be a difference, just that you can't yet rule it out.
I for one haven't even compared the two outputs and am not sure that I can hear it on my 4G, where I have done that.

Btw does anyone know where to find the datasheet for the WM8975? I can't seem to find it on wolfson's site.

 

[Jahn]

I'm a tiny bit confused here. So what happens in the Apple Radio Remote? It must receive a digital signal because there's a DAC inside the Remote - ok, that much I get. That means it bypasses the internal DAC of the ipod and avoids this whole headphone out vs. line out debate, great.

But then, how does the analog signal from the remote's DAC get amplified? Is there a teeny tiny amp in the remote too? Someone clue me in please! Or is the remote's signal actually a line out signal from the remote's DAC that REALLY isn't tied into the ipod's internal amp that goes to the headphone out (and maybe the ipod internal analog line out)?

in which case, the Remote might be the "cleanest" signal from the hard drive, even considering the extended length of the remote's cable carrying the digital signal?

 

[greenleaves]

I have not ruled out a SQ difference in both. I believe there will be a SQ difference but just that it is so insigificant that I have not detected it in my listening.

I have pointed out in another thread that the Redwine mod could possibly make a significant SQ difference by physically replacing the caps and other stuffs along the signal path up to the line-out. But that is a very different story involving hardware changes. In the end you still cannot bypass the internal amp in the usual sense for better amp stage outside, and the iPOD EQ remains functional in the line-out.

 

[BavariaBarbarian]

Agreed.

But the claimed iMod results seem to indicate, that the output of the WM8975 is pretty high quality.

Hmm... if that radio remote really has it's own dac, then there must be a digital output somewhere on the dock-connector. Interesting...

 

[divad68]

I notice a clear difference in SQ between using the headphone out and Apple's Universal dock, both through my Hi-Fi and via my X-can v3 into sennheiser HD650's. The top end via the line out appears less 'gritty' and more refined to me. Given that the Universal dock is apparently not a 'true' line-out (you can adjust the volume via the ipod) I decided to buy a Sendstation Pocketdock, but for some reason that sounds worse than the headphone out. I've now ordered a Turbodock, hoping that it will offer an improvement over the Universal dock.

 

[forsberg]

Quote:

Originally Posted by divad68 I notice a clear difference in SQ between using the headphone out and Apple's Universal dock, both through my Hi-Fi and via my X-can v3 into sennheiser HD650's. The top end via the line out appears less 'gritty' and more refined to me. Given that the Universal dock is apparently not a 'true' line-out (you can adjust the volume via the ipod) I decided to buy a Sendstation Pocketdock, but for some reason that sounds worse than the headphone out. I've now ordered a Turbodock, hoping that it will offer an improvement over the Universal dock.

What version ipod are you using?

 

[divad68]

Quote:

Originally Posted by forsberg What version ipod are you using?

5g 60gb

 

[divad68]

Quote:

Originally Posted by divad68 5g 60gb

By the way, I think I should add that I am very happy with the SQ via my headphone out (better than my mini), just that I do notice an improvement with the line-out.