Neil Young to take on Apples dominance of the mobile music sceen

[Mr. Analog]

AM is great for music that was recorded in the 50s.

I disagree, high fidelity stereo recording for big labels was the standard by the mid-to-late 40s so you can find decent quality mixes for a lot of the better music from that period onward. What started happening was a rush of small time record labels making their own masters in basically a garage were more interested in finding a new talent they could sell to a big label and recorded a lot of demos that eventually got airtime and became recognized classics. If you can imagine the scene from "Brother Where Art Thou" where the guys are singing into tin cans at the transmitter while a demo platter is being cut at the same time.

Home stereo became commercially available in the 40s and started to gain traction with many recording artists of the time.

For example, here's The Harmonicats' version of "Peg o' My Heart" recorded in March 1947 in high quality stereo:
http://youtu.be/_QWa-76_-oM
(it charted for 21 weeks in Billboard, peaking at #1)

To give you an idea of what the big labels were capable of just about anything by Decca (and subsidiaries) sounds pretty amazing, for example Buddy Holly's "Everyday" sounds as fresh as the day it was recorded (May 29, 1957)
http://youtu.be/ty31QY5ZGHo

Decca by 1954 had an impressive array of stereo equipment for recording live music (rather than mixed in post) called the Decca Tree

That said AM is really great for what's called "Wall of Sound" style of production developed by Phil Spector. It was specifically designed to sound good on AM radio and jukeboxes. If you had an AM station sitting just outside the US running an overpowered transmitter next to a large body of water you could get some big sound out of the AM band (think of "The Big 8" CKLW Windsor Ontario or any of the "X" AM stations out of Mexico blasting sound into Texas / SoCal). So a lot of Motown and Doo Wop sounds great on small speakers because that's mostly what it was designed for.

[Tom]

I dunno. A lot of older music I hear sounds like it was recorded onto mono lo-fi. It's grainy, and tinny... But I probably picked a later year than I should have

Though that buddy holly recording is a bit... I can't find the right word for it. Maybe the sound is intentional. But his voice doesn't sound quite "right" to me.

[Mr. Analog]

It depends on the artist, the recording process and where the digital copy came from. There's a lot of crappy second hand copies that made it on to CDs in the 80s and 90s and generally dominate what you'll find online. I have an original first run copy of Dion and the Belmonts "Presenting Dion & The Belmonts" (1959) that sounds amazing compared to some of the tracks I've been able to find online. Most likely tape masters were made in the 70s for 8-track and then used again in the 80s for CD release and then again for subsequent re-releases in the 90s and 00s to maintain copyright. Which is a shame, the original LP is a really well mastered work IMO

Buddy Holly sang from the throat on that particular track, not something a lot of singers do because it's hard to maintain and sounds weird, but it's sharp as heck and has a lot of depth.