XLR and RCA interconnects in the same system?

I was wondering if someone could tell me if you have XLR interconnects between your cd player and your preamp and RCA between your preamp and amp does that negate the benefit of the XLR not having balanced inputs on all the components?
In my opinion NO. In my system I prefer rca's. With XLR the gain is too high for me but the soundstage is just a hair wider.
Just my preferences.
What is the benefit as you see it? IMHO, the primary benefit is the potential noise-rejection over a balanced line. So, for each connection that uses it, you benefit (possibly).

My understanding is that the benefit of a balanced connection is a lowering of the noise floor. My guess, subject to correction by an engineer, is that there is some benefit to using a balanced connection between component and preamp, even if the connection from preamp to amp is RCA, since the signal the preamp is receiving is carrying less distortion. I would think that benefit would carry through to the amp. But it's just a guess on my part.
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Thanks the only reason I bother is that I have the Cambridge azur 840 CD player and I just got 840 azur preamp the CD player as a balanced out and the pre has a balanced in and I have been told that the 840c really reacts well to balanced cables my amp is a McCormac DNA1 which is great but only has RCA inputs
Thanks Again
Hi Mxb, you are a brand new member here,... I researched, and your CD has balanced and unbalanced out. Your Pre has balanced and unbalanced in, also balanced and unbalanced out. Your choice. My PRE (which I like) has only balanced out. My AMPS (which I like) have only unbalanced in. My IC (which I like) (so), I had made up xlr-rca. end of equation. find what works for you.
Hi Liz...you're very wrong. If (and only if) your system is completely balanced from beginning to end, there is a definite advantage.. providing the components are truely differentially balanced. Most components that sport XLR connections are Not balanced and therefore provide no benefit in using balanced interconnects..they are there to impress the purchaser that the circuit is of a higher quality. I am using an all Ayre system which is indeed diferentially balanced...a more expensive circuit having a seperate plus circuit, and a duplicate but phase reversed minus circuit. You can clearly hear that balanced cables sound better than any RCA terminated cable. The sound is quieter, more open, with greater ease.
Fully balanced is always best , ( balanced in and out ) but as Kal mentioned there is still noise reduction with each balanced cable used . I have A/B/A tested this many times over the years and in many , many systems and the results are always the same .
"05-03-11: Stringreen
Hi Liz...you're very wrong. If (and only if) your system is completely balanced from beginning to end, there is a definite advantage.. providing the components are truely differentially balanced."

Offered as a blanket statement, this is simply untrue. Almost (note the qualification) all devices with XLR connections have fully balanced connections and, therefore, offer the benefit of reduced RF/EMI noise pickup, regardless of whether they are "fully balanced" throughout their circuitry. The latter is much rarer and has the potential for better performance but is not necessary for the establishment fully balanced connections.

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"Actually balanced is just a buzzword used to sell stuff. it has NO value over RCA at all for any system except the fully balanced from beginning to end electronics."

Yes it does have value over RCA. It suppresses noise much better, prevents disconnect, prevents touching live wire.

I agree with Kal that benefits of XLR are independent of benefits of system being completely balanced.
I have'em all balanced now:
Technoarm rewired to have balanced(just split the ground wire onto two and connect +,- and ground accordingly 2x2=?); Classe 30 phono inputs rewired to balanced as well; CD to preamp balanced from the beginning; Tape in-out rewired to balanced(for AtoD recording); Headphone amp is with balanced in/outs. Did a 'brutal' job on Classe 30 chassis(this preamp I bought with imperfect chassis for the low hundreds). Had to eliminate 'video' and 'aux' inputs in order to increase space. Other than that, the preamp is fully balanced from the beginning with all necessary isolation of negative signal path from the ground. Piece of cake just like rewireing to convert all inputs you need. Certainly out pre to poweramp is balanced from the beginning.
There's no indeed RCA cable for ANY price that will sound better than cheap XLR.
The effect on the analogue set up was extreamly amazing: gain, definition control went high up above!
I now have a few projects of converting to balanced that I implement for friends for now (SS equipment only for now but will think of tube designs as well). I plan to charge x-amount per converting each input/output unbalanced to balanced and probably 3...4x amount for converting same for tube equipment depending on amount of chassis work.
Hi again Liz.... Actually isn't "theory" as you suggest. Anyone doing an A/B between balanced and single ended can clearly hear the difference. I guess using mid-fi equipment it makes no difference....however in the persuit of perfection, balanced is indeed better.

K4r...just plain "Nope" with the caveat that there may be some minor benefit using XLR with non balanced circuit...however, the real benefit comes with fully differentially balanced circuitry.
Can there be connectors better than XLR, theoretically?
I understand the theory of both balanced interconnections and of balanced circuit design and they accomplish different things. So, Stringreen, which is the "real benefit?"

Kr4....listen and be enlightened. I am a musician, not a scientist. I place my trust in my ears.
I second the comments by Kal, Kijanki, Rdavwhitaker, and others that a balanced interface can sometimes provide significant sonic benefit regardless of whether the components are internally balanced or not.

In addition to the reasons they mentioned, I would add that a balanced interface will provide considerably reduced susceptibility to ground-loop issues, and also will reduce sensitivity to cable effects and differences (particularly if the output impedance of the component driving the cable is low).

Ground-loop issues, btw, do not just involve hum problems. They can also result in an increased amount of low-level high frequency noise, resulting in degradation of "background blackness."

Does all of this mean that using balanced interfaces between components that are not internally balanced is generally preferable? Of course not. It is dependent on the quality of the implementation in the particular components, numerous unpredictable system-dependent variables, and overall system synergy.

But as I see it, it all clearly means that a blanket claim that using balanced interfaces between components that are not internally balanced will necessarily result in little or no benefit is incorrect.

It's ironic that listening experience here is being used to deny the possibility of significant sonic benefit, while science is being used to advocate that possibility. Usually it is the reverse that seems to occur.

-- Al
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Elizabeth - you can compare only equivalent XLR to RCA. It might not make any difference in your system if you don't have ground loops or noisy environment but I like to think about it as a form of insurance against possible problems. I use short runs of one of the best neutral sounding XLR cables hoping not to ever change it. I don't see any reason not to use XLR since my DAC and power amp accept it while the price difference is minimal.

In addition my Rowland 102 amp has only XLR inputs. This seems to be the latest direction Mr. Rowland goes since his latest expensive class AB model 625 power amp has also only XLR inputs. Obviously he sees benefit of it and I trust him completely.
Elizabeth, an example of my reference to "reduced sensitivity to cable effects and differences (particularly if the output impedance of the component driving the cable is low)," and note that I did not say NO sensitivity, I said "reduced sensitivity," would be the ground-loop induced high frequency noise, and consequent degradation of background blackness, that I referred to. And ground-loop induced hum, as well.

With an unbalanced interface, the severity of those effects will be directly proportional to the resistance of the cable shield, or other return conductor if the return conductor is not the shield. That resistance, which is usually not specified, will differ unpredictably for different cables. With a balanced interface, differences in that resistance will not matter, or will matter very little, because the receiving circuit is essentially responding just to the difference between signal line voltages, not to the difference between signal and return line voltages (the return line being what is sensitive to ground-loop effects, because it is normally common with both chassis and AC safety ground).

Also, you may have seen in the past several comments by no less an authority than Atmasphere, making the following two points:

1)A balanced driver circuit that has low output impedance, and is capable of driving low impedance loads (specifically 600 ohms) without signal degradation, will result in there being NO sonic differences between the balanced cables that may be used to connect that output circuit to the destination component.

2)Many and probably most balanced driver circuits are not designed with that capability, and hence will not provide that benefit to the degree that it should be provided.

Finally, I can recall seeing more than a few threads here in the past in which people indicated that in their experiences balanced interfaces seemed less sensitive to cable differences than unbalanced interfaces.

-- Al
The comment that a cheap balanced connection (using cheap wires) for the balanced interconnect is good?
That is hogwash.

If you have poorly designed, poorly built and/or mismatched audio equipment the I agree.

Some people just don't get it - with well designed gear the effects of audio cables are minimized to the point of being negligible...
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It is simply semantics - my definition of "high end" is gear that reproduces what is on the recorded media as accurately as possible with the least possible distortion from extraneous factors such as cabling.

Those who invest in setups that magnify the effects of cables to the point of audibility are simply hearing much less of what is on the recording. A system should be tuned to the recording and de-tuned to all variable extraneous factors like power and audio connections.
Answering the OP's question - no, mixing them does not negate the benefits.

There seems to be a lot of misunderstanding of how balanced topology is used to reject noise. A fully balanced system will sum the positive and negative signals at a number of points in the chain, to cancel noise that has crept into those two feeds, so that you get a clean single-ended signal, and then it is split again (or transformer-buffered) for the next stage. Each balanced stage achieves benefits that are independent of prior or following stages. There is no need for a system to be balanced end to end in order to get the benefits of balanced operation in one stage.

The downside is that a balanced system will therefore tend to have more active or transformer buffer stages inserted into the signal path, and this is not usually a good idea in gear made to a low to mid-price.

Single-ended cables have greater interaction with the system's ground plane, than do balanced cables, and this is more likely to account for sound character differences in typically short audio cables, than is external noise rejection (RFI, EMI...).

Additionally, the design of many single-ended interconnects does not translate into a balanced design without significantly changing the simple electrical parameters of LCR.

The trouble is that it costs more to build balanced gear than single ended gear, so it is not obvious whether, dollar-for-dollar, one is superior to the other. And a lot of XLR inputs are often not balanced at all.

As a wild generalisation - where gear is designed for single-ended sound and balanced interfaces are added as an after-thought, single-ended will usually sound better. The reverse is also true. Gear designed around balanced operation will usually sound better with balanced cables.