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 Sometimes it's just old and out-of-date.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.
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.