Battle of RCA Cables: Mogami, Amazon, Monoprice

[Saponetto]

I know I'll get a lot of olive kernels thrown at myself, but...
it's a lot of time I only use SommerCable Spirit LLX with Amphenol RCA plugs for all my interconnections.

For sure it's subjective matter, but my ears tells me that high impedance inputs of my tube amps strongly needs low capacitance cables.
Of course, for any other low-impedance use, some feets of Onyx 205 of same brand works really fine.

 

[SIY]

For sure it's subjective matter, but my ears tells me that high impedance inputs of my tube amps strongly needs low capacitance cables.
Of course, for any other low-impedance use, some feets of Onyx 205 of same brand works really fine.

The relevant factor is source impedance not load impedance.

 

[Saponetto]

Honestly I don't know how to approach about it, I currently use a D30Pro or a D70 as my sources, both via their unbal RCAs, and for sure both have a quite low impedance output...
what really puzzles me is that a tonal differences (some raise-up of the mid-high) -only- become audible when I plug my EL34s SEP amps, that have near 100KOhm input impedance.
Of course solid state amps do not ingenerate this event... maybe I'm somewhat biased, but if I use those cables I almost cancel this tonal difference.

 

[SIY]

Honestly I don't know how to approach about it, I currently use a D30Pro or a D70 as my sources, both via their unbal RCAs, and for sure both have a quite low impedance output...
what really puzzles me is that a tonal differences (some raise-up of the mid-high) -only- become audible when I plug my EL34s SEP amps, that have near 100KOhm input impedance.
Of course solid state amps do not ingenerate this event... maybe I'm somewhat biased, but if I use those cables I almost cancel this tonal difference.

Your issue is less likely electrical.

 

[Deleted member 46664]

Since we're on about RCA cables....

That is a $10.00 6 foot RCA cable passing 200khz in an input to output Null test .... What more do you need?

 

[Saponetto]

Your issue is less likely electrical.

Thanks, I'll work on it.

 

[Lambda]

That is a $10.00 6 foot RCA cable passing 200khz in an input to output Null test .... What more do you need?

This is measured with an 8bit ADC? so you maybe have 48dB dynamic max. but surely not in this >150 pixel high waveform.
also output/ input impedance is unknown.

What mor?. how good is it shielding against electrical noise
common mode current. captive coupled noise and inductive coupled noise.

Every wet string is an "ok" cable over short distances if noise is low output impedance is low and input impedance high.

ADSL Robustness Verified By Running Over Wet String

A core part of the hacker mentality is the desire to test limits: trying out ideas to see if something interesting, informative, and/or entertaining comes out of it. Some employees of Andrews &…

hackaday.com

Phono is maybe the most demanding consumer application for an rca cable.
Low signal level and high amplification so every bit of noise gets amplified a lot.
High output impedance so cable capacitance has a chance to make a difference.

If a cable works it usually "works" and there is no magical improvement. Noise is a common problem many uses have.

 

[Deleted member 46664]

This is measured with an 8bit ADC? so you maybe have 48dB dynamic max. but surely not in this >150 pixel high waveform.
also output/ input impedance is unknown.

The signal originates from a signal generator. The screen shots are from a free standing oscilloscope.

The input impedance is 75 ohms (from the signal generator)

The output impedance wants some explanation...
Usually these cables operate at about 1 volt or less into a 10K or higher input impedance. This is very typical in modern equipment.
For the test I jacked the voltage up to 2 volts and added a 1k resistor as a dummy load... so the cable was operating at 20 times normal stress... AND it still nulled at over 200khz with an acceptable signal.

 

[Mihalis]

Question: I had a long cable from the phono preamp to my preamp/amp setup. If that cable would approach within 30-40cm of two 3KVA power transformers I was using to feed the system, I could hear very audible "static?" "tzzzzzz" noise from the speakers. Am I correct this does confirm that under certain circumstances these cables can act like antennas and insert all sorts of noise? in this case length was long, I think around 4m (which isn't something I do now) so I also wonder if there is a length below which this doesn't apply or if length is irrelevant for this type of noise. XLRs. Thank you.

 

[Speedskater]

a] with a RCA unbalanced interconnect system, picking up AC power line noise that close to a big transformer is not surprising.
b] No, noise antennas work in a different way.
c] in a harsh noise environment like that, the best plan is to use a well designed XLR balanced interconnect system and a Star Quad cable.

 

[Holmz]

… Am I correct this does confirm that under certain circumstances these cables can act like antennas and insert all sorts of noise? …

More like the transformer itself…
Where the RCA gets magnetically induced current in it.

It is just not a great transformer as the RCA is not wrapped around the iron core.

 

[Mihalis]

But I was using XLR.

 

[Holmz]

Usually twisted pairs XLRs are pretty immune…
It must have some large fields around it.

 

[Deleted member 46664]

Question: I had a long cable from the phono preamp to my preamp/amp setup. If that cable would approach within 30-40cm of two 3KVA power transformers I was using to feed the system, I could hear very audible "static?" "tzzzzzz" noise from the speakers. Am I correct this does confirm that under certain circumstances these cables can act like antennas and insert all sorts of noise? in this case length was long, I think around 4m (which isn't something I do now) so I also wonder if there is a length below which this doesn't apply or if length is irrelevant for this type of noise. XLRs. Thank you.

What you are describing is hum induction ... and yes any piece of wire is subject to that ... even the massively expensive stuff.

XLR cables pick up noise too, don't kid yourself... what is different is that in a properly implemented balanced audio system they have developed the means to cancel the noise at a device's inputs and keep it out of the electronics.

Balanced Audio

The ins and outs of balanced audio

dbpages.ca

 

[NormB]

Thanks, Amir. (or AmirM?)

Getting back into audio/phono 3 years ago after a nearly 40-year hiatus when my very pricey (I thought) ONKYO all-in-one up and died and, out of warranty, factory shop quoted a price about half of original cost IF no special order boards/parts needed.

Fuggeddaboudit.

I went with more ADCOM, long story, never mind.


For connectors, I cheaped out with the Monoprice and found the short 1ft jumpers were SO stiff they pulled out of the sockets all on their own which kind of freaked me out mid-song. NOT the preamp/amp. WHEW!

After some comparison shopping, Audioquest considerations (SO many choices, although I DID buy one of their lower-priced ones to connect my TT to my Musical Surroundings Nova III phono stage), I went with WBC's line as a more reasonable price point.

As a disabled vet, recently retired, pricier cable options just weren't tenable.

Now I know. Wonder if those cheap, 30 year old cables are still around.

 

[Deleted member 50971]

@amirm I realize this is an older thread but I was wondering if the Amazon basics RCA cables use a stranded or solid core conductor, and if they are all copper? I saw where they are 23 AWG but it doesn’t mention the material used. Thanks.

 

[milosz]

@amirm I realize this is an older thread but I was wondering if the Amazon basics RCA cables use a stranded or solid core conductor, and if they are all copper? I saw where they are 23 AWG but it doesn’t mention the material used. Thanks.

Well, at that price you know for sure they're not using silver wire....

I would bet any reasonable amount of money that they use copper; why would they use anything else? Aluminum is a pretty good electrical conductor, but why would they use aluminum? It would probably be special order / more costly to source for the conductors used in these cables, so they wouldn't do that. Aluminum would work, but there would be no advantage to it, except to save a few grams per cable in weight. And these are not aerospace cables.... and they wouldn't use steel, that would be crazy and would dull their tooling.

And more likely than not, the core is stranded. Why don't you buy one, cut it apart, and let us know? They are not expensive - c'mon, sacrifice for Science!

 

[Human Bass]

I'm not sure if I already posted in this thread: gotham gac-1 ultra pro is my favorite wire for rca. Robust, flexible and with 4 layers of shielding in a coaxial configuration.

 

[Killingbeans]

@amirm I realize this is an older thread but I was wondering if the Amazon basics RCA cables use a stranded or solid core conductor, and if they are all copper?

Only ever seen silly alchemy based audiophile cables with solid core conductors, so... most likely stranded

 

[Human Bass]

Considering buying some new RCA interconnect cables to replace some old Monoprice Premium cables which have stiffness issues and sometimes disconnect from time to time due to the orientation of my desktop gear.

I see a lot of people recommend star-quad wire indiscriminately, be it Canare, Mogami, Belden or any other brand, for unbalanced RCA interconnects. I've also read that this is overkill for the application as it was designed for balanced signals and the extra capacitance of the star-quad wire may actually make it a worse choice for unbalanced RCA interconnects. I'm not concerned about the minor cost difference for the shorter lengths and number of cables I need between the two, so this leads to my questions:

Should I choose a pliable name brand twisted pair or star-quad wire for RCA interconnects? Is there a definitively better choice for the application?

Star-quad is awful for rca, makes no sense at all. It picks up more noise (more wires "working" as antennas) without the balanced topology to nullify this noise. Coaxial is the way to go.