Paul , I am Old School and like to keep it stock. These SA-1's sound so incredible, I personally feel to keep it as is. But not to plug my cable, I do have a BMI Hammerhead Gold power cable on it, which just puts the SA-1 in another universe of it's own.
Out of all the digital equipment I've owned over the past 20 years, the Marantz SA-1 has the best results with an upgraded power cable.
At an original $7500 msrp and now under $4K preowned for the SA-1. I would have to say it's a steal when you Hear the sound.
The lesser units such as the Marantz SA-14, SA-14mk.2, SA-12S1, SA-8260 and now there current flagship SA-11 are not in the same league as the SA-1. I personally know the design, and the parts of each.
And according to Marantz, the SA-1 is clearly a statement design. Marantz couldn't make anymore of the SA-1's because of unavailability of the custom design laser and chip. This is from first hand telling from Marantz people.
So again, if you can find a Marantz SA-1 keep it unmodded and it's better than having money in the bank. Because I can guarantee not just now, but years to come the SA-1 will be a sought after player. You can't say that about too many other players. I am done with this topic.
Brian