Do you use XLR or RCA single ended to your near speaker located amps?

[stehno]

I would've closed the thread and just had a poll if it was an option... there is no guise. In fact I think you're downright insulting for saying otherwise. That is especially since you bother to preclude that way and then continue to post a lengthy bit after.

I agree with CGabriel's initial comment.

I also agree with much of his remaining post as he is experienced with some good info to share. Especially in regard to SE's having in at least some instances (like mine) the potential to sound a tad more accurate over XLR.

Though I've not tried it yet, I did a little unrelated experiment a few years ago that leads me to believe potentially any amplification along the signal path is doomed to increased distortions. However slight they may be, it all adds up in the end. Since many balanced outputs (true or otherwise) approximately doubles the voltage from 2 volts (SE outputs) to 3.5 - 4 volts (XLR outs) I have to assume (based on my unrelated experiment) that amplified voltage step may well be introducing a bit more distortion and hence the final presentation being a tad less pristine and delicate.

I've been using XLR cables for maybe 14 years now primarily because it's always been a tad more dynamic (due to the additional voltage) and somewhere I have a list of little things to do which includes swapping out the XLR cables for SE ic's and I suspect I'll be mildly surprised with the results.

 

[Folsom]

Seriously? God I hope Steve can delete everything but the pole...

 

[SCAudiophile]

Agree this should have just been a poll to get the answer if that was the true intent of the original post. I happen to utilize true balanced XLRs as my equipment is balanced in design but there is a large amount of equipment out there where SE not only sounds better for that particular design but in many cases (tube offerings come to mind), it is the only option. That assumes the RCAs are properly constructed of course... What performs and sounds best is very specific to the equipment in question. On exception, for runs 3 meters (my number, not a standard) up to 10-meters and longer, I have always found XLRs to sound best even if the equipment is not a balanced design. I've not experienced Zeel interconnects at 50-ohms like those Mike L. has in his system but have heard from him and others, this is a superior standard and for lengthy runs given what the over-wire-spec and method of cable construction were designed to do, it would be the way to go and I wish my equipment supported it.

 

[microstrip]

These arguments, this time in the guise of a poll, are largely pointless and irrelevant. The requirements for signal distribution in a studio or professional environment are different than what is needed in a home audio system. Recording studios and post production labs have multiple components that capture, transmit and manipulate the audio signal and the various components can be very far apart. For these environments, true balanced lines with differential signaling help prevent the introduction of external EMI/RFI to the audio signal.

In a home audio system many components do not have balanced inputs or outputs. So the only possible method of signal interconnection is through a single-ended interface which usually means, RCA, BNC or phone jack connectors. So, for these systems the relevant question would be how to maximize signal integrity and minimize the introduction of noise and hum. This can be accomplished by using cables specifically designed for single-ended transmission and by keeping the cables relatively short. Generally, it is best to keep cables under 3 meters in length however lengths over 10 meters are possible without any problems.

Home audio components that have XLR connectors may or may not have "balanced interfaces". There needs to be a definition of terms first. We need to discuss the three elements involved in a signal transmisison. There is the sending interface, the interconnecting cable and the receiving interface. Lets start with the receiving interface. It is designed to receive a symetrical differential signal. This signal is fed to a driver that amplifies only the difference between to hot(+) and cold(-) signal wires. Common mode noise is therefore eliminated. But this is only true IF the signal that arrives at the input to the receiving interface is actually "symetrical". In a balanced transmission there are two signal wires. Both carry the signal but they are 180 degrees out of phase with each other. They must each have exactly the same impedance to ground. This also means that the sending interface must send a symetrical signal. Only if the sending interface sends a symetrical signal AND the interconnecting cable preserve that symetrical signal integrity AND the receiving interface is a differential interface designed to receive a symetrical signal will the potential benefits of "balanced transmission" be realised.

In a pro environment the equipment is usually designed with true differential interfaces. In home audio it is all over the map - there is no consistently used standard across brands and manufacturers.

Shocker: Balanced connections don't necessarily sound the best if your equipment has both options available. Most electronics circuits are not differential through the amplification stages even if they provide balanced connections. To output a differential signal, the signal must be run through an audio transformer or through a buffer stage that creates a positive and negative differential signal. There are no perfect transformers and the extra differential stage can degrade the absolute signal purity as compared to a simple signal-ground output. This is why many designers of tube equipment only provide single-ended connections.

There is much more to it but that is enough for now I think.

Thanks Caelin. Your great summary focused the important points to address and why putting everything in a "pseudo-configuration" is misleading.

 

[microstrip]

If Vladimir calls it pseudo balanced what can I call it

For me I use XLR cable for the strength of the terminations vs RCA. TO me it is an elaborate SE cable with XLR terminations, nothing more

If you are using XLR from the Lamm preamplfier to the ML3 it is more than that. Since both pin3's are directly grounded you are using the extra signal wire as a ground wire, reducing the impedance of the ground cable between the units - a good think. You are also using two additional ground pins. However some people will argue that a proper RCA plug has lower ground impedance than a XLR that was not prepared for such use - we can not please everybody! IMHO some people like to know these details, probably it is why Lamm fits the two types of connectors.

In principle pseudo balanced means that the signal is not differential but that both signal impedances seen at the XLR pins are equal - there is no inverted phase, but a true differential input will cancel cable induced noise but will not double the amplitude or reject power supply induced common noise.

 

[ddk]

My main interest is knowing the "why's" of each of us ...

Single Ended sounds more natural to my ears than balanced which I find hifi in comparison. Using balanced wires with Single Ended designs is still SE.

david

 

[Steve Williams]

Single Ended sounds more natural to my ears than balanced which I find hifi in comparison. Using balanced wires with Single Ended designs is still SE.

david

And this is the reason the Vladimir and several other manufacturers only believe in SE and provide the XLR inputs and outputs for the strength and security as several members have suggested

 

[ddk]

And this is the reason the Vladimir and several other manufacturers only believe in SE and provide the XLR inputs and outputs for the strength and security as several members have suggested

It's also because many already have balanced wires and he's providing XLR jacks for them.

david

 

[Ken Newton]

...For these environments, true balanced lines with differential signaling help prevent the introduction of external EMI/RFI to the audio signal.

An balanced interface is NOT synonomous with differential signaling, nor is differential signaling even required. They are distinct principles. One could have single-ended signaling combined with an balanced impedance interface, or, for that matter, differential signaling combined with an unbalanced impedance interface.

...Lets start with the receiving interface. It is designed to receive a symetrical differential signal...Common mode noise is therefore eliminated. But this is only true IF the signal that arrives at the input to the receiving interface is actually "symetrical".

Perhaps we are speaking at cross definitions on this, but signal symmetry has nothing to do with how a balanced interface cancels common-mode noise. A balanced interface means that the impedance to ground is the same (is balanced) for both the signal's two conductive paths. It's only the impedance balancing that nulls the common-mode noise. The drive signal can be symmetric OR asymmetric with equal effectiveness as far as an balanced interface is concerned.

In a balanced transmission there are two signal wires. Both carry the signal but they are 180 degrees out of phase with each other...This also means that the sending interface must send a symetrical signal. Only if the sending interface sends a symetrical signal AND the interconnecting cable preserve that symetrical signal integrity AND the receiving interface is a differential interface designed to receive a symetrical signal will the potential benefits of "balanced transmission" be realised.

Forgive me, but that is incorrect. Again, signal drive symmetry has nothing to do with what defines a balanced signal interface. It's strictly a matter of interface impedance terms.

 

[ddk]

I'll be honest I'm mostly interested in numbers. I've seen both personally, but I haven't seen as many systems as there are on here.

Are you looking for just XLR wires or balanced electronics, because you can still use XLR wires with SE electronics and it means nothing?

david

 

[ddk]

Same here as far as using single ended Lamm gear. When I rotate to CH I get to use the same cables but this time fully balanced. All there is to it really.

But the Lamm M1.2s that you use have balanced circuitry.

david

 

[sbo6]

Hi, I was just wondering how many people use RCA single ended vs. XLR cables to their amps that sit next to their speakers (longer runs).

Ignoring all the detritus and getting to your question and poll - I use single ended from the preamp to amp since that's all my amp accommodates.

 

[Mike Lavigne]

Single Ended sounds more natural to my ears than balanced which I find hifi in comparison. Using balanced wires with Single Ended designs is still SE.

david

that has also been my experience, preferring the little bit more unrestricted connection to the music with single ended circuits. and in my experience I've also felt that single ended is actually quieter.....more 'see into' than balanced. my gut tells me that there is just less 'stuff' in the way of the signal.

however; I've not lived with enough balanced circuit gear to have strong feelings that that is a truth I could defend. it's more just an observation. maybe it's just the gear I've chosen to spend time with.

and possibly systems with inherently low noise and which are very well sorted out might not need what balanced offers. so it could be a synergy thing too.

 

[CGabriel]

I would've closed the thread and just had a poll if it was an option... there is no guise. In fact I think you're downright insulting for saying otherwise. That is especially since you bother to preclude that way and then continue to post a lengthy bit after.

Oh sorry. I didn''t intend that as an accusation. The subject just comes around in many different "forms" I guess is a better way to put it.

 

[RogerD]

I use SE because my equipment dictates it. I really don't think it matters though because the majority of home systems do not have a pathway to ground as good as the best recording studios. Like one poster mentioned most consumer gear is a hodgepodge of design as far as grounding schemes. Professional recording studio design has been written about for years by engineers like Whitlock,Muncy,Brown and the high end is just starting realise that grounding schemes are very important for signal integrity and signal noise rejection.

An balanced interface is NOT synonomous with differential signaling, nor is differential signaling even required. They are distinct principles. One could have single-ended signaling combined with an balanced impedance interface, or, for that matter, differential signaling combined with an unbalanced impedance interface.



Perhaps we are speaking at cross definitions on this, but signal symmetry has nothing to do with how a balanced interface cancels common-mode noise. A balanced interface means that the impedance to ground is the same (is balanced) for both the signal's two conductive paths. It's only the impedance balancing that nulls the common-mode noise. The drive signal can be symmetric OR asymmetric with equal effectiveness as far as an balanced interface is concerned.



Forgive me, but that is incorrect. Again, signal drive symmetry has nothing to do with what defines a balanced signal interface. It's strictly a matter of interface impedance terms.

And in my experience a balanced system (ground) in consumer high end depends on the size of the pathway used in a star grounding scheme. Less so in a commercial scheme.

 

[JackD201]

But the Lamm M1.2s that you use have balanced circuitry.

david

I use an L2 Reference with the Ms.

 

[Ken Newton]

...Using balanced wires with Single Ended designs is still SE.

david

Hi David,

Not necessarily. It all depends on whether or not the signal interface has a properly balanced impedance to signal ground, which requires proper wiring of the balanced interconnect cable - i.e., no pin-1 problem. Whether the line driver circuit is single-ended or differential is not relevant. Actually, I'd say that probably the easiest type of line driver circuit to give a balanced signal interface to are single-ended, not differential.

 

[ddk]

Hi David,

Not necessarily. It all depends on whether or not the signal interface has a properly balanced impedance to signal ground, which requires proper wiring of the balanced interconnect cable - i.e., no pin-1 problem. Whether the line driver circuit is single-ended or differential is not relevant. Actually, I'd say that probably the easiest type of line driver circuit to give a balanced signal interface to are single-ended, not differential.

Hi Ken,

Is that common among SE electronics?

david

 

[ddk]

I use an L2 Reference with the Ms.

I know L2 has SE inputs only but it does have a balanced outputs, I assume that you use your CH pre the same way or am I wrong?

david

 

[Ken Newton]

Hi Ken,

Is that common among SE electronics?

david

I'm uncertain, but I don't believe it is common, which is unfortunate because it's quite easy to do and typically requires a minimum of additional passive components. Typically, only one resistor if the circuit is D.C. coupled, or one resistor and one capacitor if A.C. coupled, per channel. Perhaps, the common misunderstanding that a balanced interface requires a differentially driven signal is part of the reason.