RCA replacement for phono help

[4D_Coaxial_Cube]

So I decided to replace the RCA cable on a Denon turn table from the early 80s and discovered the RCA donor has an extra wire. The original RCA cable configuration is simply an internal jacketed positive cable for left and right and the ground mates to its own spot on the board, however, the donor cable I chose is a Monster THX Certified cable (whatever that means) that has a red and white internal wire along with a jacketless silver wire with shielding over all of them before the final housing. I dont know what to do with the extra wire if anything. Does it need to be soldered to the negative tap on the board with the internal white wire or covered with electrical tape?

 

[4D_Coaxial_Cube]

 

[USER]

I recommend you make things easier on yourself and get a similar cable. As your replacement cable is two conductor it is thicker and can put a lot of strain on the soldered connection and cause you a lot of headache. But if you are going to use it simply clip the ground wires and use the second conductor instead. But make sure it is super secured.

But more importantly, are you using a MC or MM cartridge? If the latter, do you know the capacitance of the Monster Cables? Cable capacitance is extremely important for MM cartridges as you more or less add it to that of the phono preamplifier in order to know the total capacitance of your set-up and be able to load the cartridge correctly. If you know the cable capacitance you can customize it by adjusting its length. This is one of the few areas where cables are actually important. Again, with MC cartridges, this doesn't matter so much. But with MM cartridges you want to be able to be within recommended numbers. For example, Audio-Technica cartridges generally do much better with lower capacitance. In this way you can work with your phono preamplifier to load your cartridge correctly.

I use this with my Denons. https://www.amazon.com/gp/product/B01BTLANW8/

It is thin and pliable and offers great shielding. More, it has relatively low capacitance so you are not limited by length, ~20pF/ft. I have a total of around 110pF with a little under 5ft including the connectors and this matches my preamplifier well, which has loading settings of 0-200pF, affording me 110-310pF for loading. With this I can properly load almost any MM cartridge. Unfortunately prices have shot up this past year. I imagine most of the market is like this now.

 

[4D_Coaxial_Cube]

Well, I guess I really wasted 4 bucks at thrift on this monster cable that I destroyed, or maybe it can be a donor for something else....maybe I can find a used WBC like this on the baybay. Thanks a lot for the input. How can I check the capacitance of the Monster cable to make sure I am not switching cables for no reason? I mean, I did acquire this cable for less than five bucks and if the capacitance is close enough then I wont have to spend 10 times as much for the same thing.

 

[4D_Coaxial_Cube]

I also know a seller that makes custom Beldin cables for very cheap, how would those work? W/o the RCA termination on one end I assume it would be even cheaper and this seller does such custom building of cables.

 

[JSmith]

So I decided to replace the RCA cable on a Denon turn table

I hate to ask... but it feels like the elephant in the room. Why?


JSmith

 

[4D_Coaxial_Cube]

I hate to ask... but it feels like the elephant in the room. Why?


JSmith

Longer length, also, the back side of the rack is full of cheap power cables that probably have poor shielding running next to the phono cable. The ends are worn and dont clamp as well. Older cable probably doesnt use single crystal copper...just to name a few.. oh, and magic, dont forget cable magic.

 

[DVDdoug]

Longer length,

You probably won't know the capacitance unless you buy the raw cable and solder the connectors yourself...

You may know this already - Cable capacitance is rated in pF per-foot (or per-meter) so double the length is double the capacitance. And the total capacitance is the cable plus the input capacitance of the preamp (possibly unknown). ...Plus any capacitance from the wiring inside the tonearm & turntable.

And of course, longer cables are more prone to noise pickup. (Usually not an issue with lower-impedance, lower-gain, line-level connections but possibly a concern with a phono cartridge.)

Normally parallel capacitance makes a low pass filer that reduces high frequencies (if it has any effect). But the inductance of the phono cartridge makes a tuned circuit and (to a point) more capacitance tends to bring the resonance down closer to 20kHz and boost high frequencies.

The cartridge manufacturer usually specifies a load of 47K Ohms and some optimum capacitance.

Like USER says, all of that is only for "regular" moving-magnet cartridges.

...Personally, I'm fairly "casual" about this stuff because no vinyl setup is "perfect" and most of the defects/weaknesses are in the records themselves... I wouldn't worry about capacitance. I don't play records but I occasionally digitize one and I'll EQ if it doesn't "sound right".

I dont know what to do with the extra wire if anything.

Some turntables have a chassis-ground connection, separate from the signal ground. Usually that's a completely separate single-wire but you could use that one if it's convenient to make a chassis-ground connection at the other end.

 

[USER]

How can I check the capacitance of the Monster cable to make sure I am not switching cables for no reason?

Use an LCR meter. This one is good, though it has nearly doubled in price recently. You can often get one cheaper from China.

Amazon.com

You'd want to use the short connectors. Unfortunately multi-meters tend to overshoot their readings. You really want an LCR meter.

Don't forget that the other reason you may want to consider something else is that the Monsters are super thick and if improperly secured may tear out the connections and ruin your turntable.

I hate to ask... but it feels like the elephant in the room. Why?


JSmith

The Denon cables are often around 3ft long, which is pretty darn short

...Personally, I'm fairly "casual" about this stuff because no vinyl setup is "perfect" and most of the defects/weaknesses are in the records themselves... I wouldn't worry about capacitance. I don't play records but I occasionally digitize one and I'll EQ if it doesn't "sound right".

Fortunately we are in an era where the layman can obtain a lot of information regarding their vinyl set-up. One can really hone it in. As with anything else EQing by ear is a terrible idea when there are better options.

Introducing the Phono Cartridge Measurement Library

After years of development we are finally launching our phono cartridge measurement library. These measurements were created using the brilliant cartridge response python script written by @scott wurcer and @JP. Information about its origins can be found in the following threads...

www.audiosciencereview.com

 

[4D_Coaxial_Cube]

Use an LCR meter. This one is good, though it has nearly doubled in price recently. You can often get one cheaper from China.

Amazon.com

You'd want to use the short connectors. Unfortunately multi-meters tend to overshoot their readings. You really want an LCR meter.

Don't forget that the other reason you may want to consider something else is that the Monsters are super thick and if improperly secured may tear out the connections and ruin your turntable.



The Denon cables are often around 3ft long, which is pretty darn short



Fortunately we are in an era where the layman can obtain a lot of information regarding their vinyl set-up. One can really hone it in. As with anything else EQing by ear is a terrible idea when there are better options.

Introducing the Phono Cartridge Measurement Library

After years of development we are finally launching our phono cartridge measurement library. These measurements were created using the brilliant cartridge response python script written by @scott wurcer and @JP. Information about its origins can be found in the following threads...

www.audiosciencereview.com

I might have gotten locked in on the Monster after remembering that I altered the plastic grommet to accept the Monster cable. Its very thick and seats like a bear in a school desk. I dont think it will be going anywhere. Its very long so I will probably cut it down to 4 feet. Do I disregard an inner wire or the bare one outside the 2? I might spring for that 4ft WBC cable if it doesnt sound right. If it knocks the highs down I may like it more.. if it raises them up I will buy the other.

 

[AnalogSteph]

The Denon cables are often around 3ft long, which is pretty darn short

You'd get about 0.7 m with a Technics if memory serves, which would be even shorter.

Longer cables are not the answer. Placing the phonopre near the turntable is.