So what is different about a phono cable vs SE RCA?

I just got back into vinyl after a 30 year hiatus. I am in the market for RCA to RCA phono cables for between my VPI Prime Scout and Sutherland KC Vibe mkII. I need RCA to RCA with an additional ground wire. The rest of my system is all Purist Audio Venustas Luminist so I want to stay with them. I was looking for any demos or used but nothing on phono cables, only standard RCA. So my question is what is the difference or could I use standard RCA's with an additional ground wire?

 

I use Blue Jeans, but my system isn’t at your level but subscribing to see what others have to say.

https://www.amazon.com/gp/product/B00OJLNEOU/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

 

Capacitance matters with phono cables, which makes length critical. The phono cables are also more critical on shielding due to carrying a much lower output signal. Plus there's the extra ground wire to deal with.

 

VPI makes one, I bought one from Music Direct a few years ago




VPI Link below:
RCA Cable

also

VPI Tonearm Cable Double Shielded-Audio Advisor

 

More so with MM and HOMC carts. Not so much for LOMC.

 

OK, so last night I took my Purist Audio Venustas RCA Interconnects off of my digital and put them on my turntable between the TT and phono Pre. I used an additional ground wire to go between the TT and ground on the phono pre and I heard zero additional hum. So can I use a standard RCA cable with an additional ground wire?

 

Capacitance and shielding are the two biggies.

 

Yes, that is fine. They are a little high in capacitance at 40pF per foot, but good construction with a Teflon dielectric, so if they aren't too long and your cartridge isn't too sensitive to the capacitance load (and while not specified, I think the Sutherland phono preamps have very low input capacitance), they should work well.

 

A bit more on capacitance and dielectric: In general, one thing to look for in an RCA cable for turntable use is a foamed dielectric vs. extruded. That's usually a good indicator of low capacitance.

 

Question: So what is different about a phono cable vs SE RCA?

Answer: At least $150.

 

That's an old joke.

The answer is it has to be really, really good. With a moving coil cartridge, you can easily have one hundredth of the voltage passing through a phono cable. Even a moving magnet cartridge will only put out a tenth of the voltage of a line-level signal. Not only is the quality of the wire really important, so are the connectors. You want the best of both, and that costs money.

 

At the phono preamp capacitance loading like 100 or 200pF really does not matter. But at the cartridge end it does, especially for MC, you want a cable with very low cap, ideally below 100pF per meter, this allows you to load higher at the phono stage and not restrict the cartridge. I have a pr of Morrow Audio Grand Ref PH6 phono cables rated at like 560pF per meter, I can set the loading on my Nova II at the lowest 30 ohms and sounds bad, push it to 121 to 200 ohms and sounds constricted. Swap in my AQ Cougar phono cable at like 60pF and set loading at 475 ohms and the cartridge sings with huge dynamics and resolution.