• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Doesn't 1/4" RCA negate the benefits of XLR connectors?

Dunring

Major Contributor
Forum Donor
Joined
Feb 7, 2021
Messages
1,468
Likes
1,657
Location
Florida
A lot of stuff is going to 1/4" RCA, and I have adapters and also 1/4" to XLR cables. I just saw some "Worlds Best" cables advertising the star quad design and they were 1/4" to XLR as well. Doesn't the RCA end completely remove the benefits of XLR though? Audibly I can't tell any difference in things like noise floor. It just seemed odd they would do a star quad design in a cable seemingly designed to defeat the benefits with a TRS 1/4" end on it.
 
It depends... Driving from a balanced or differential connection (XLR), you can keep the outer shield so the signal runs on the inner conductors for additional noise rejection until it is plugged into the RCA jack (then it is up to the receiving component). The same is potentially true for RCA into an XLR cable, with the outer shield not carrying signal return ("ground"). So maybe not "completely" but you do lose noise rejection, and of course virtually all common-mode rejection is lost at the RCA (single-ended) connection. I have had components that actually "float" the RCA ground from chassis ground help maintain balance and noise rejection, but those were usually pro mixers and such (and one old preamp did it to help break ground loops).

But yah star-quad with an RCA seems like overkill to me... - Don
 
Erm XLR, RCA Phono, and 1/4" (6.25mm) or even 1/8" (3.5mm) are all connectors and only one of them is definitely unbalanced.
XLR is generally balanced (+ve, -ve, gnd) and TRS versions of both 1/4" and 1/8" could easily be wired for those same three electrical connections.
RCA has only +ve/hot and ground signal lines.
1/4" and 1/8" TS connectors would be unbalanced as they only have two poles.

Typically TRS connectors are wires as unbalanced with a common ground shared for both left and right - think typical headphone cables.
Some 1/8" connectors or even those really thin 2.5mm connectors are TRRS 4 pole and might be on some headsets where there is a mic signal as well as left and right and a shared ground.

I guess, for unbalanced connections they are just using the Star Quad as they buy it in such huge quantities it is cost efficient to use what they have.
It's decent cable all the same, low handling noise and decent electrical characteristics for audio signals.
 
I'm stupid, what is a 1/4" RCA?
I know what an RCA is and what a 1/4" plug (or jack) is.
But have no idea what a 1/4" RCA is?
 
Balanced inputs can provide some noise rejection, even when driven from an unbalanced signal/connection. Of course, if you don't have a noise problem it won't change anything.

I recently built a circuit with that configuration... a balanced (differential) input with RCA connections... No ground until the unbalanced connection with a ground was plugged-in. It was an odd-special application but it solved my (ground loop related) noise problem.

I don't think balanced outputs to unbalanced inputs have any benefits and you have be careful if you "ground out' a signal wire.
 
Really easy and dirty way (two resistors and a cap) if you know a couple of things about your gear:

 
Back
Top Bottom