SCD-1 & SCD-777ES Sonically What's the Difference?

Some units have two DACs outputting a true differential signal that is then amplified in a differential analogue stage.

An op-amp inverter used to create a balanced signal does, as you say, provide the balanced output that is useful on longer interconnection runs, but the typical user does not run such long interconnects. These users expect a better quality signal from the balanced output (I don't know why), so an added stage that may degrade the signal is a bit of a disappointment.

I have a pro audio background, and every time I see someone calling a balanced out a "fake balanced out" I have to laugh. This is one of those tweaky audiophile distinctions that is lost on the rest of the world.

A balanced output simply means that there are two signals - the original and an inverted version. They share a common ground. The whole point of a balanced out is to allow for very long cable runs without introducing cable-induced noise, or losing big chunks of signal. So, a balanced output enables common mode rejection, and has high gain to support the long cable run.

The balanced outputs on the SCD-1 do this job just as they should. So how is that "fake?"

And yes, I know about an inverted signal derived from a "differential" split output versus an op-amped flip-flop. The fact is that it makes no difference regarding the purpose of a balanced out. Most pro audio gear simply flips the signal with an op-amp or similar inverter circuit.

The power supply is the same,it's the 2 encapsulated transformers($340 without labor)that is the main difference.Add to that,the fifth foot,balanced outputs(fake or not,it can still be used with balanced equipment)and don't forget their difference in appearance.I did prefer the SCD-1 to the 777ES when comparing the two,though it was not night and day.I do feel the transformers play a large role in regards to these differences.Gary.

My understanding is that there is essentially no difference, aside from the use of an inverter to create a "fake" balanced output available on the SCD-1.

If you like the looks of the 777, or don't really care about looks, you made the right choice. I bought the SCD-1 years ago not knowing that there was no relevant difference between the two.

Williamdc

You may be correct here. I vaguely remember my SCD-1 service manual making reference to dual power supplies with SCD-1 in parenthesis only. But I am not sure it was power sipplies or transformers. However,I am to lazy to go digging through my service manual to find it. The service manual does go into great detail concerning the circuitry for the balanced outputs but makes no reference as to whether or not they are truly balanced.

Thanks, Chuck

The SCD-1 also has better stock feet than the SCD-777ES. It makes a slight difference.

And it doesn't have two power supplies either.

The transformer is potted in the SCD-1, however.

but it's not truly balanced

I believe the SCD-1 has 2 power supplies plus balanced outputs. Sonically there probably isn't a difference.

Chuck