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Why aren’t BNC jacks common?

Digital connection between a source component and DAC calls for typically other a 75 ohm impedance or 110 ohm impedance cable. Sourcing a 110 ohm cable is easy- it’s very common. But a 75 ohm cable? Not so much primarily because just about every RCA terminated cable is not a 75 ohm cable, however, true 75 ohm cable is a snap with BNC terminations. BNC is not expensive and arguably it’s a more secure connection than is RCA. I therefore do not understand why components with BNC jacks are very rare. Perhaps you can argue the ommission of a BNC connection is justified on mass market gear but on high end gear?  Can someone provide an explanation that makes at least some sense? My DAC supports BNC (Bricasti) but my CD transport (Simaudio) does not. Thanks!! 

zavato
palasr
541 posts
 

Older Naim preamps used to use a mix of BNCs (for phono inputs), and DIN connectors for line level inputs and outputs.  Not an XLR or RCA in sight!

kevemaher's avatar
kevemaher
381 posts
 

@carousel 

Not true. BNC connectors have been the standard for 50 ohm cables in electronic instrumentation for many, many decades. Certainly more reliable than the RCA ones.

I am all for adopting BNC as the connector of choice in audio systems (XLR is also good for balanced cables. Reluctance to adopt new ideas has hampered its widespread consumer use and will undoubtedly continue to do so.

carousel's avatar
carousel
31 posts
 

Indeed, I am a big fan of XLR. I have zero Cinch-RCA in my systems. Only balanced.

oldeaudiophile
6 posts
 

LONG ago I ditched rca's and converted all my equipment to bnc.

Yep, the so called cognoscenti at Audio Research would and did howl I'd violated their warranty... but then again I as an licensed avionics repair station engineer I rarely set anything back to them anyway! So YES BNC should be the  standard. By the way most rca connections are very close to 50 ohm imp.  

oldeaudiophile
6 posts
 

By long ago, I meant from the 1970's. Dick Sequerra, George Kaye, John Curl, Bob Fulton, Dick Marsh in my experiences with them (in and outside audio) all agreed and used them on their personal systems or research designs.

 

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