New TT : Balanced vs. Unbalanced Connection?

Sleepwalker, I hope you get the salient point that ICs per se count for nothing if the phono stage (in this instance) is not capable of balanced operation. Therefore you can’t have one without the other. These days there are components that provide XLR inputs but do not treat the signal in balanced mode. 

that Rega video,

converting factory 'solid' rca's to 'quite delicate' XLR seems to me a fine example of stubborn or obsessive absurdity. 

You muddy the waters when you mistakenly claim they aren’t balanced.

@cleeds  I've not once anywhere on the web made the claim as you suggest above. I think you misunderstood something, since what I posted previously did not contradict this statement of yours:

It’s a simple fact that designs such as the excellent ARC products will yield 6 db greater gain when run in balanced mode.

My comment was regarding a phono cartridge. So let's examine that and you'll see I was right. Let's start with the single-ended connection: the output of the cartridge is applied to the input of the phono section and ground. The total output of the cartridge might be 0.5mV. Now if you apply that same cartridge to a balanced phono input, the output of the cartridge is unchanged- its still 0.5mV. So there is no '6dB increase in output' of the cartridge- it is in fact exactly the same.

As I mentioned in my post, at the output of a balanced preamp that does not support AES48, there can be a 6dB in the apparent increase in gain if that output is connected to a balanced amp as opposed to single-ended. That is because a non-compliant balanced circuit simply has two single-ended outputs, one out of phase with the other. So if you use one and get a Volt out of it, if you use both you get 2 Volts which is a 6dB increase.

If the circuit supported AES48 then neither output references ground- they reference each other (like you see at the output of a phono cartridge). Its worth noting that this means that to drive balanced lines correctly (IOW to winnow all the benefits of the technology, such as interconnect cable artifact immunity and immunity to ground loops) what ever is driving the balanced line has to be floating source.

You don't have to do it that way of course but if you do it gets better.

@gemoody The cartridge screws was a tip from @mijostyn, not me.

@elliottbnewcombjr That is a bit odd- XLRs are a lot more rugged than RCAs.

Oh, and one more thing, phono cartridges produce a differential signal that is not referenced to any ground

@sleepwalker65 Actually this is the literal definition of a balanced source. So the output of a phono cartridge or tape head is inherently balanced.

atmasphere

I've not once anywhere on the web made the claim as you suggest above ...

Here is what you wrote:

When you run a cartridge balanced, it supports the standard. So no increase in gain.

If you run a cartridge "balanced" (technically, it's floating) into a differentially balanced phono preamp such as an ARC Ref Phono 2SE, you will have 6 dB more gain in balanced mode than unbalanced.

For home use, the advantage is that a properly set up balanced line will minimize the 'sound' of the cable.

That's is your opinion and I respect it. But many others think the advantage is:

... good rejection of common-mode noise and interference ...

... as noted in the Wikipedia link I previously provided.

... the output of a balanced preamp that does not support AES48, there can be a 6dB in the apparent increase in gain ...

That is misleading because it's not an "apparent" increase in gain. It's a genuine, specified, measurable increase in gain. Or, if your prefer to look at it another way, it's a 6 dB improvement in S/N.

Ralph @atmasphere, there's no question that you're expert and manufacture fine products, many protected by your trademarked and patented circuits. But there's more than one way to execute balanced circuits, and you're obviously prejudiced against those who take a different approach.

@gemoody 

Don't forget the test record!