The older ones were very good and I still have mine. If you do some critical listening between them on factory settings, you will see that older ones are a touch louder and maybe a little clearer but don't take that as overall better, so please read on.
On the older 4500s there is an extra hum you can hear when activating Enhance (need good headphones and good hearing) which a lot of people can't hear, but those that are sensitive to high freq sounds can find it annoying. If you match your threshold tone to the hum the two sort of blend.
Now the first thing I noticed during the testing phase on the 5000 was that this hum was less noticeable, but also very faint signals were noticeably a little quieter, but easily offset by increasing your Target Volume by a couple numbers. The changes were necessary to get the best performance out of Fine Gold.
I have listened to the newer 4500 (I'll call this the 45v2) in Enhance vs the 5000 in Enhance and they sound identical to me, which pretty well confirms the 45v2 units are more similar to the 5000s (apart from obvious settings changes).
One point of difference between the older 4500 and the 5000 (and 4500v2) is the target signal is a little "fuller" sounding. It is only very subtle but quite noticeable on targets on the limit of their detectable depth. This is a similar effect to what the SteelPhase Enhancer achieves, and why it marries up nicely to the older 4500, as it beafs up that often fluffy signal response. On the 5000 it is even beefier and you can run the clearer Filter 1 position but I'm getting side tracked.
So overall, if you had an old 4500 on optimum settings vs. a 45v2 on optimum settings, I really doubt you'd see much of a difference. There are very subtle differences but I don't think it's worth worrying about.
The newer 4500's are perhaps a better match with the new spiral wind coils as they just just run nice and stable, very important when using a highly sensitive coil.
Hope that helps.
:Y:
