db loss?

[Gordon]

I have a newb question for you folks. I was using XLR IC's and just installed 2 pair of RCA ended IC's. I thought I read somewhere that there could be a db loss using RCA's. Quite surprising to me to have to turn it up as much as I did to achieve the same measured volume level.

Am I out to lunch or did I learn something today?

Gordon

 

[benleeys]

I have a newb question for you folks. I was using XLR IC's and just installed 2 pair of RCA ended IC's. I thought I read somewhere that there could be a db loss using RCA's. Quite surprising to me to have to turn it up as much as I did to achieve the same measured volume level.

Am I out to lunch or did I learn something today?

Gordon

Balanced (XLR) preamp output is usually about 6dB higher than RCA. That's why one can use longer cable runs without fear of losing too much signal along the way. Also, balanced cables, by nature of its 3-wire construction, are less prone to hum pickup in an unfavourable environment. One can therefore say that replacing XLR connections with RCA is a step downward in signal quality.

 

[Gordon Gray]

Balanced (XLR) preamp output is usually about 6dB higher than RCA. That's why one can use longer cable runs without fear of losing too much signal along the way. Also, balanced cables, by nature of its 3-wire construction, are less prone to hum pickup in an unfavourable environment. One can therefore say that replacing XLR connections with RCA is a step downward in signal quality.

Sorry about your generalization but I respectfully disagree. Potential advantages of balanced over single ended does not necessarily infer better signal quality and superior performance.

Esoteric recommends single ended over balanced for their DV 60 CDP, which is a $5K unit and has both types of outputs.

Conrad Johnson, a highly respected high end manufacturer, typically does not have balanced connections on their electronics.

Too many variables and lots of theories (not mentioning listening tests) for this to be "absolutely" true.

GG

 

[David Matz]

I have a newb question for you folks. I was using XLR IC's and just installed 2 pair of RCA ended IC's. I thought I read somewhere that there could be a db loss using RCA's. Quite surprising to me to have to turn it up as much as I did to achieve the same measured volume level.

Am I out to lunch or did I learn something today?

Gordon

Here's one hypothesis: I am assuming you are using Mac eqipment. Mac is not designed to be truly differentially balanced (such as Ayre, BAT, Bryston, some ARC, etc.). They just add another set of connectors to accommodate people with cables, without spending money on building out balanced circuits. Thus you are not hearing anything different. The db difference is evident with my Ayre and BAT stuff, but the equipment also sounds better in balanced mode due to the design. My CJ amp sounds awesome with RCA only.

 

[C.A.P]

Unless the unit has fully balanced circuitry its useless to try XLR. The Krell Equipment is and there is a huge difference in sound and db level. The CAST outputs even further push the envelope !

 

[benleeys]

Sorry about your generalization but I respectfully disagree. Potential advantages of balanced over single ended does not necessarily infer better signal quality and superior performance.

.........Too many variables and lots of theories (not mentioning listening tests) for this to be "absolutely" true.

GG

In the case of non-balanced mode equipment, it would be quite correct to say that sound quality does not necessarily improve with balanced connections.

I erred only in not specifically mentioning that my statements refer to equipment with balanced circuitry. To use RCA connections here would be to defeat the purpose of such a design and compromise the sound quality. Since he mentioned a significant dB loss, I had assumed (possibly another error here) that Gordon's equipment was such.

 

[OldMonolith]

To reply to Gordon's original question...

Most likely, here is what your referring to about level difference in between balanced and unbalanced interconnects.

RCA's, being unbalanced have a single signal connection to pass the audio.

XLR's, being balanced use two conductors to pass the audio. The signal phase is 180 in difference between them. So when one signal is going positive, the other conductors signal is going negative at exactly the same voltage level.

So the receiving device has twice the voltage present to work with...which is a 6db advantage. Also, (and the big reason to do a balanced connection) since the signal coming into the component is looking for all information to be at opposite phase, it can REJECT anything that is in the same phase (Common mode rejection). This means that any noise picked up by the cable can be ignored on the receive end since any noise will be equally impressed upon the signal on both legs of the balanced connection.

The other reason that you may have heard of a level difference is this....the traditional "line level" used for RCA unbalanced connections is -10db. On pro balanced connections it is +4db or even +8. This additionally hotter level allows the professional system to run signals further and reject noise due to the balanced connection. The penalty is that it takes much greater capability (and expense) to run those signals that much higher!

Hope this helps you understand the story!!

OldMonolith:music: