AudioNervosa
Electro Stimulation Ward => Signals and Noise => Topic started by: jessearias on May 31, 2016, 07:12:06 AM
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I got into a discussion with an amp manufacturer (solid state) the other day and he said his amp sounds better when using the RCA inputs rather than the XLR inputs. He makes his amps with both inputs, but prefers the RCA's.
I always though that using balanced connections was the way to go if so equipped.
Anybody have any opinions on this?
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The manufacturer of my amp prefers xlr
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I modified a Gainclone design to accept balanced inputs. Sounds much better to me as balanced input.
Depends on the design used and how well it was implemented as to how it sounds.
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The maker of the Red Dragon M1000 Mk1 Monoblocks I have preferred XLR over RCA inputs. I can't think of a manufacturer that stated they found RCA unbalanced sounded better than XLR. I always thought manufacturers put RCA inputs on their amps because that is what is more available to the masses.
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It depends.
If it is a TRUE balanced design then XLR is the way to go.
On the other hand, a simple unbalanced design will not have the extra 'noise' a less than ideal balanced design so I can understand why manufacturers decided to go the unbalanced route.
Personally, I prefer RCAs. :)
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Depends on the input stage. Jfets seem to love their XLR. Where mosfet goes nice with RCA. Or Not.
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I got into a discussion with an amp manufacturer (solid state) the other day and he said his amp sounds better when using the RCA inputs rather than the XLR inputs. He makes his amps with both inputs, but prefers the RCA's.
I always though that using balanced connections was the way to go if so equipped.
His amps are probably single ended topology. A balanced (differential) signal requires conversion to single ended signal before the single ended amp can use it. Balanced to Single Ended converters (BAL/SE) come in different types, and levels of performance. Usually it is an opamp. The additional opamp(s) can change the sound a little, or in some cases a lot. The ones that change it very little, like THAT 1200, are relatively expensive so not used in consumer audio. High open loop gain opamps need lots of feedback to work as buffers and that changes how they sound. rarely are opamps used with the gain structure that makes them sound their best, and each opamp has different gain sweet spot. A common sight is the TI LME 49xxx series used in unity gain. Nothing kills the music better than that, but it's everywhere. Thank you John Atkinson for spewing your editorial load about the LM4562, predecessor to LME49xxx series, as the risen Christ savior of audio technology back about 8 years ago. A whole editorial column about an opamp! omg A 'New Deal' for Audiophiles. not
An input transformer type of BAL/SE converter is mostly transparent, but they cost a lot (LOT) more so they are rarely seen in consumer gear. I think Purity Audio Design uses input transformers on their flagship preamp. YAY Go Bill!! :thumb:
Balanced signal was created to reduce noise picked up in cables. It allows filtering out the noise picked up along the cable. Residential audio systems are not exposed to the kind of noise the pros face, so we really don't need balanced signals. Single ended signal can work just as well, if well engineered.
That said, my favorite amps always seem to be fully differential type though.... :-k which I dutifully feed with differential signals when possible.
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Thanks Richadoo for the great explanation. :thumb:
The inputs (RCA, XLR) are switched on my Parasound A21, so I am guessing it uses an Opamp circuit to process the XLR signals or can be switched to bypass into single ended.
The amp in question (Odyssey Statos) is not switched. I am guessing it has an Opamp circuit as well as a single ended circuit. I guess the Opamp section changes the sound enough that it sounds better in single ended mode.
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It depends.
If it is a TRUE balanced design then XLR is the way to go.
On the other hand, a simple unbalanced design will not have the extra 'noise' a less than ideal balanced design so I can understand why manufacturers decided to go the unbalanced route.
Personally, I prefer RCAs. :)
Agree 100%.
charles
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I recently asked a manufacturer the same question and they said it's a toss up. They compared the same model cable in both versions and said that they didn't notice any noise differences but a slight volume difference.
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My preference in commercial audio gear is PASS. Nelson designs his gear balanced to wrench the greatest performance with the fewest parts. The fewest parts: that is the key phrase here. His design topologies are brilliant in design application AND the parts he chooses.
Problem that I have with most balanced gear is the quasi-balanced approach where there is often a dual conversion done in what is essentially a single ended, not differential design. Then comes parts count, selection and matching, etc.
I prefer single ended from a use standpoint, all things being equal. Just easier. With modern parts and wise implementation great performance can be had IF we don't need the inherent 6dB bump from differential input - see PASS. He is a master of gain structure in design. He is also a master at building room heaters :D
THAT1646 is the deal for use as a single ended to differential line driver. There are more than a few very high end pieces of studio gear that rely upon them. Whitlock is a hell of a designer for devices as well as transformers.