Vintage Power Amp vs new age power amp

>Modern amps on average have wider bandwidth, faster rise
>times, higher current, higher damping factor, lower
>distortion, and audibly better signal-to-noise ratio.

Not necessarily true.

Compare Nelson Pass's Threshold amps from the 80s, and 90s with his Pass Lab's amps from the 90s to date. They generally have the same specs. Just different implementation, which is why many gravitate towards his older stuff because price-per-amp, vintage is hard to beat even including replacing the supply caps. This is also true for old Krell and McIntosh gear.

In any event, the specs are one thing but not always indicative of better performance.

>Electronic parts (capacitors, resistors, printed circuit
>boards, etc.) are better as time moves on...there are new
>materials, or construction techniques, etc. that makes these
>black boxes perform better. Even though there is excellent
>older stuff, the excellent newer stuff is better.

I would agree that better manufacturing techniques now can lead to tighter tolerances. However, I would not necessarily agree that that results in modern amps sounding better than vintage amps.

They sound different, but one (modern or vintage) is not better than the other.

As for banana plugs, I actually don't like the ordinary ones. Over time, they can use tension (and thus a solid connection). One option is the locking bananas. Somewhat costly, but a solid connection.

Sort of a new Mustang vs an old Mustang w/ a rebuilt engine, suspension and modern tires debate. I had a Rotel RB-1080 power amp lots of power, well built, good synergy with the rest of my system- good looking amp. The McIntosh 2100 that replaced it just beat it. Not by a lot, but in a way that said "I'm a classic. There's a reason for it- listen". Oh and the McIntosh uses spade lugs-eesh....

It's like I said before: Good sound is where you find it. Some vintage stuff became audio classics for good reason--it was ahead of the curve, or it achieved a great balancing act between the science and art of audio. OTOH, not everything that's old is golden. Sometimes it's just old and out-of-date.

By and large the new stuff is faster and cleaner, but not necessarily. However, there are landmarks in all periods. One such is the Marantz PM804 integrated amp. At $999 it's like getting a 70 wpc integrated in 1972 for $190. Back then, you couldn't get an amp with the bandwidth combined with its s/n at *any* price.

But OTOH that doesn't mean you'll give up your Eico for it. Like I said, good sound is where you find it. I say this as someone who listens with great pleasure through a 1981 Heathkit AA-1600 power amp. There may be better amps out there, but not at the $239 I paid for this audio classic.

As for the original OP, whether to get that Marantz 300D or buy new, the asking price on the Marantz combined with your own visceral reaction to the sound of the Marantz is your only true answer.