Anything wrong with iPod dock for line out?

[K2Grey]

Quote:

Originally Posted by agile_one Just did a quick experiment to try to answer the question of line out from a 5g video iPod using the Apple universal dock - Model A1153, with the ir port for a remote. I never use this, as I have an ALO Silk for lineout duty, and that IS a true line out. Set my trusty 5g 60 gb iPod in the dock, ran mini-mini to my Hornet, and had a go. Lo and behold, both camps are correct - the line out via the Apple universal dock can be level adjusted with the iPod's volume control, AND it is a steady line out that is unaffected by the iPod volume setting. How can this be? Easy - depends on the operating system used. Boot to Apple firmware (I have the 6/28/2006 version), and the iPod's volume control rules - ie: not a true line out from the Apple dock. Boot to RockBox (I have the 8/2/2006 build), and the iPod's volume control has no affect on the signal - a true line out from the Apple dock. So, it seems the dock itself is not the culprit, rather the firmware/software that drives it. I am totally in the RockBox world now, so no issue for me, and I am glad to confirm that I can use the apple dock and get a true line out signal from my 5g video.

Actually, I believe the impression you have gotten is not correct.

The last time I heard, the volume control is in the signal path even with Rockbox. There is no way to remove the volume control. The Rockbox developers took the advice of head-fi posters and fixed the volume control to 0db (that is, no boosts or cuts). But the volume control is still there.

Edit: Furthurmore, I believe the volume control used is digital attenuation by the DAC. Thus, whether or not the volume control is there is irrelevant to whether it is a "true" line out or not. For example, with a computer based setup you can attenuate the sound in foobar2000 regardless of what the hardware is. Look at linuxstb's posts in this link:

http://www6.head-fi.org/forums/showthread.php?p=1957471

 

[gdg]

The software issue is moot. Whether or not it enables the volume control is neither here nor there since in either case it's still in the signal path. The fact that the volume cannot be controled with an Audiolineout dock imeans that the lineout pins are being used. The the apple dock must be accessing a diffenent set of output pins.

Gerry

Ps Redwine Audio confirmed this for me this afternoon.

 

[Sinwerm]

Quote:

Originally Posted by gdg The software issue is moot. Whether or not it enables the volume control is neither here nor there since in either case it's still in the signal path. The fact that the volume cannot be controled with an Audiolineout dock imeans that the lineout pins are being used. The the apple dock must be accessing a diffenent set of output pins. Gerry Ps Redwine Audio confirmed this for me this afternoon.

Exactly. As I remember it , they (apple) set-up the line out for the Apple made universal dock to use the pins (on 5g ipods) to have the volume circuit active. Other docks use the "true" line-out pins. Odd choice no ?

 

[Large4mat]

Quote:

Originally Posted by Sinwerm Exactly. As I remember it , they (apple) set-up the line out for the Apple made universal dock to use the pins (on 5g ipods) to have the volume circuit active. Other docks use the "true" line-out pins. Odd choice no ?

Very poor choice IMO. Makes me wish all the more that I had picked up a NOS 4th generation Ipod.

 

[kwkarth]

Quote:

Originally Posted by Sinwerm Exactly. As I remember it , they (apple) set-up the line out for the Apple made universal dock to use the pins (on 5g ipods) to have the volume circuit active. Other docks use the "true" line-out pins. Odd choice no ?

Frankly, if the volume "circuit" is digitally implemented, then its presence will have no effect on the analogue quality of the signal as long as it's set to max, which it is when employing the line out connection. I am still pretty sure that the head amp buffer in the 5G iPod is bypassed with the line out connection. I will verify this today and report back.

 

[kwkarth]

The line out connection drives a pair of headphones directly at what sounds about like 70% volume. I suspect the iPod uses a different output buffer for line out than for headphone out for two reasons:

1. The directly driven sound from the line out connection is clearer, more open, and has better depth. The headphone output, on the other hand, is rolled off at the high end, is more closed in and constricted sounding.

2. The volume control operates the headphone out volume only while simultaneously having no effect on the line out. As far as I know, you have to have two separate buffers to pull this off.

The EQ controls operate on both outputs as most of you know, but again, since this is in the digital domain, it should have NO effect on the audio quality if left set to flat.

 

[Melletron]

Quote:

Originally Posted by gdg With respect to Cryo'd cables I was being sarcastic am fully aware that cryfreezing is probably done with liquid nitrogen. That's not the point. The point is that I've been around audio long eneough to have heard just about every mumbo jumbo tweak out there. These "magic" solutions are designed to prey on people who have no concept whatsoever of how engineering and science actually work in reality. I have good cables in my sound system (Wireworld Equinox 5) but I can assure you that they are simply well made cables that sound significantly better than most. They don't require suspension in air, orientation with the "Chi" energy meridians of the planet or any other such nonsense. There may well be something to Cyo freezing but I seriously doubt it and will be pleasantly surprised if they turn out to be superior. Gerry

I don't know about any of this stuff, but I can tell you that this cable rivals the cotton and for me it started out with two strikes against it. One, it's stranded and two, it's copper. I'm a silver guy, but this cable sounds awesome. To my ears it's got the best of both worlds, like the cotton. And seemingly indestructible like... well, like no other.