Experiences With Costly Balanced XLR Interconnects Above $3,000

Well since all the cables sounded the same, that begs the question why the preamp couldn’t discern the differences.

@dave_b 

No, it doesn't and that's not a thing... Let's put it another way? Its good you have the resolution to hear cable differences. Its bad that you actually do.

Next year most audio manufacturers will have a better preamp, better amp, better DAC, and better speakers.

Yes. But as we all know, cables can cost as much or more than a component. One customer of mine had balanced interconnect that cost $1000/foot ten years ago and he had 24 feet.

Wouldn't it be nice to just not to ever have to worry about what the cable is doing in your system; to have it reliably always be completely neutral, without it being an investment?

To understand how balanced lines are supposed to work, look at it this way:

With RCA cables, the sound of the cable is dependent on its construction, which might cost quite a lot.

With balanced line, if the standard is supported, the equipment is doing the heavy lifting rather than the cable. This results in plug and play.

I knew Robert Fulton back in the late 1970s. He pretty much founded the entire high end audio cable industry. Back then, people thought he was nuts, with his Fulton Gold 8ga speaker cable and his Fulton interconnects. We (my audiophile friends and I) were listening to differences in audio cables way back then.

But I also played in various orchestras and those got recorded. I was able to listen to the direct mic feeds on several occasions, and the thing that really stood out was how amazing they sounded, through cables that were clearly a lot longer and lot older than Fulton’s cables.

The recording stuff was balanced. Fulton’s cables were single-ended.

So from as far back as 1973, I had this lesson that balanced line cables worked and that was why when it came time to design a preamp, I designed what turned out to be the first balanced line tube preamp ever made. The first units were sold in 1989.

Of course we played with a lot of cables back then. Before we had a line stage going that supported the balanced line standard, we built a passive balanced volume control. Running 30 foot cables, the difference in sound between them was nothing short of dramatic. The old mic cables I had on hand sounded broken next to the Kimber and Purist.

Finally we swapped in the line stage. All the cables sounded better. But the funny thing was the old studio cables sounded every bit as good as the others and they all sounded the same.

And that is why we’ve pushed balanced operation ever since.

I don’t like the idea that you can hear differences between cables- because it means that all the cables are wrong. Everyone reading this knows this is so: next year the manufacturer of the ’best’ cable will have a better one and if he doesn’t, someone else will. So that means the cables you have now aren’t right.

Now I’ve often been accused of being nuts but I don’t get why you have to spend thousands of dollars on a cable and then watch it turn into something you can’t really sell- like used underwear. Its a bad investment. I always thought that audiophiles would love the ability to ditch all that if they knew they could get better sound while using a cable they could run for decades.

Turns out some do.

But-

This thread exists...

I am curious to know why won’t manufacturers follow the AES48 standard. Do you think Audio Research, Mark Levinson, Cary Audio, Krell, and most of BAT all (Balanced Audio technology) don’t follow this standard? For the kind of money these guys charge, I really doubt they will not adhere to the standard. But then how do you find out whether a particular manufacturer adhere to the standard of not?

@pwerahera , @inna got that partially right; you can build a balanced output that does not conform to AES48 easily and it can perform quite well.

To support the standard, there are 3 ways I know of. The first is to use an output transformer and that’s how a great deal of studio equipment does it to this day because transformers do that really well and at the levels required can also have good bandwidth.

The second way, if you are going solid state (or if you don’t mind a hybrid circuit) is to use an IC like this one.

There is a third method that involves the use of a balanced circuit known as a Circlotron.

Each of these techniques have their strengths and weaknesses. Transformers are expensive and you have to pay attention to loading them properly to prevent ringing or bandwidth issues. The IC chip isn’t going to do it if you want to have an all-tube embodiment. The third way is also more expensive and to do it right probably means the manufacturer would have to pay a royalty.

So, since cable manufacturers don’t mind making expensive balanced cables, most of high end audio has chosen to ignore the standard.

With all respect to Ralph, that’s a circular argument and the claim not quite exactly true. The AES48 standard he touts was only adopted in 2019, and balanced audio circuits predate that by many decades. To suggest that only those complying with the standard are capable of such feats as eliminating ground loops is just not accurate.

@cleeds This statement is incorrect. AES48 was updated in 2019 but existed long before that and all it did was codify the existing practice. One of those practices is to ignore ground when an input or output is used (IOW the ground is only for shielding and not to complete the circuit, unlike single-ended connections). That practice goes back to the early 1950s. If you take a look at this Ampex 351 schematic you’ll see that the microphone input uses a transformer and neither side is grounded, nor is there a grounded center tap.

I would be interested to know exactly how my argument you quoted might be considered ’circular’.

In case it wasn’t clear, sure, you can run equipment that is balanced and does not support AES48, and it can sound fine. But you’ll have to audition the interconnect cable to really winnow out the best performance from the equipment. As I pointed out yesterday, you’ll never succeed at that last bit, because the best cable you were able to find will still not be right and I explained why. The equipment will also be susceptible to ground loops (which should never happen with balanced equipment...), and if you’ve wondered why some people say single-ended connections sound as good or better, its because the balanced standard is being ignored.

The balanced line standard, as it existed in 1958, made possible the golden age of stereo, along with the Westerex 3d stereo LP cutter head, and is this (long before AES48 codified it):

1. Pin 1 is ground, pin 2 inverting, pin 3 inverting (in Europe pins 2 and 3 are reversed)

2. Pin 1, ground, carries no signal circuit and is ignored by the signal circuitry. This means that the pin 2 signal is generated with respect to pin 3 and vice versa.

3. For each side of the signal, pin 2 and 3, if there is an impedance to ground, it will be an equal impedance on each side.

4. There is a low impedance aspect; in 1958 the termination standard was 600 Ohms for line level (150 Ohms for microphones).

IMO/IME if you really want cable immunity, your equipment should be able to drive loads as little as 1000 Ohms. This last bit requires a low output impedance from the circuit driving the cable. The chip I linked above has no problem doing this and you’ll notice that balanced line transformers are often designed for low impedance operation. This impedance helps swamp artifacts caused by inductance or capacitance in the cable.

BTW, this standard is used to prevent cables having a ’sound’ so you don’t have to compare cables to get things to work- its meant to allow plug and play. It has nothing whatsoever to do with how that equipment itself actually ’sounds’; your allusion to some of it sounding like ’drek’ is a red herring.

Can somebody here explain to me why $3,000 XLR connectors supposedly have a better CMRR than say $100 XLR connectors?

@pwerahera They won't. CMRR is a function of the electronics, not the cable.

The goal of the balanced line system is to eliminate sonic artifacts of the cable and eliminate ground loops. To do that, the equipment has to support the balanced line standard, known as AES48.

If this standard is supported, you'll find you no longer care about various cables because they all will sound the same regardless of cost.

But many high end audio balanced line products don't support the standard, so the benefits of going balanced are vastly reduced. Now we're back to having to audition cables!

Auditioning cables is bad because while its good you can hear the differences, its bad because you hear the differences. What that means is no matter what cables you audition and pick the best, next year that manufacturer will have a better one and if he doesn't, someone else will, and around and around we go.

The whole idea behind the balanced line system was to eliminate this problem, and if you adhere to the standard, it works. I run Mogami Neglex in my system; 30 feet per channel and maybe cost $300 for the pair. And no worries.