Phono cables - the most sensitive and critical cable in your system

engadin

Well-Known Member
Apr 23, 2022
186
162
50
61
I remember a recommendation for phono cable burn in using the signal of a cd player or tuner, connecting the phono cable with arm to the outputs of the tuner.
I think I remember having read to connect the pins at the cartridge end of the arm.
Your comments, gentlemen?
 

DasguteOhr

Well-Known Member
Sep 26, 2013
2,354
2,515
645
Germany
The LOMC cartridge has an inductance which is in parallel with a capacitance of the tonearm cable. An inductance in parallel with a capacitance is how radios tune stations...

This creates a high Q electrical resonance, usually between 100KHz and 5MHz.

It can go into excitation, activated by the energy of the cartridge despite not being anywhere near the same frequency.

Because of the high Q nature of the resonance, it can be as much as a 30dB peak!

This RFI is injected directly into the input of a phono section. If the phono section isn't designed to deal with this, it can distort and thus not sound right (usually bright). This is why 'cartridge loading' resistors are sometimes used (for phono sections where the designer did not take this phenomena into account) which have the effect of detuning the resonance, thus killing the RFI.

SUTs cannot pass frequencies this high and so block the RFI. For those phono sections that have this issue, the SUT will thus sound better.
super explained, in addition, certain cantilever materials + stylus also have resonance .
exsampe emt tsd 15 adds a calculated capacitor to smooth them out no treble rise or resonance these can even be in the low range 15kh-70khz.
Unfortunately, not every manufacturer eliminates this resonance.
after then absolutely straight frequency response in the audible range. Sorry for offtopic
20221017_075516.jpg
 
Last edited:

Atmasphere

Industry Expert
May 4, 2010
2,336
1,837
1,760
St. Paul, MN
www.atma-sphere.com
super explained, in addition, certain cantilever materials + stylus also have resonance .
exsampe emt tsd 15 adds a calculated capacitor to smooth them out no treble rise or resonance these can even be in the low range 15kh-70khz.
Unfortunately, not every manufacturer eliminates this resonance.
after then absolutely straight frequency response in the audible range. Sorry for offtopic
That will lower the electrical resonance frequency....
 

DasguteOhr

Well-Known Member
Sep 26, 2013
2,354
2,515
645
Germany
That will lower the electrical resonance frequency....
And mechanical resonance too. here are measurements of different cantilever materials and their mass and the resulting resonance frequency.from experience i can say that the boron cantilever +shibata stylus produces the most amazing treble. clean sweet perfect;)
cantiliver.JPG
 

thekong

Well-Known Member
May 10, 2012
246
135
948
Hi All, I am thinking of making a pair of phono cables out of Gotham 11301 cable. I understand from forum discussions that it is better to use cables with lower capacitance, but they usually only quote one capacitance figure.

The following are capacitance figures for the 11301. So, which figure should I go by? Would the 11301 be a good choice for phono cable?

Thanks in advance

Capacitance:cond/cond: max. 50 nF/km
cond/shield: max. 103 nF/km
Side circuit capacitance:cond/cond: max. 55 nF/km
Side circuit capacitance:Quad system max. 135 nF/km
 

Petrat

Well-Known Member
Apr 17, 2019
24
23
83
UK
  • Like
Reactions: thekong

Solypsa

Well-Known Member
Jun 7, 2017
1,811
1,399
275
Seattle
www.solypsa.com
The Gotham Coax is lower capacitance but the GAC4 is symmetrical. Are you talking tonearm or SUT cable?
 

thekong

Well-Known Member
May 10, 2012
246
135
948
Hi Solypsa, actually I will be using the phono cable in two situations; 1, tonearm to a built in SUT in a LCR phono, and 2, tonearm directly into the active gain stage of the Aesthetix Io. Would the Gotham GAC4 be better in one arrangement over the other?

I have no technical knowledge, but my gut feeling is that for phono cable, symmetrical cable is better. Any truth in this ?

Thanks
 
  • Like
Reactions: bonzo75

Solypsa

Well-Known Member
Jun 7, 2017
1,811
1,399
275
Seattle
www.solypsa.com
In general for 'pre SUT' connections I would agree, symmetrical is better. IO has balanced inputs right? Do you know how the LCR inputs are wired up?
 

MaccaAu

New Member
Oct 3, 2022
4
0
1
39
I am researching cables for the phono cables, i think my diy silver cables would not have the best capacitance,

Internal wiring
Van Dame 268-100-00 3.6 outer diamter. 47pf/m core to core 152pf core to sheild.

Mogami 2497 looks familar to the old atlas cables i had once
Mogami 3159, 2803, 2944, 2965/4
 

Atmasphere

Industry Expert
May 4, 2010
2,336
1,837
1,760
St. Paul, MN
www.atma-sphere.com
I am researching cables for the phono cables, i think my diy silver cables would not have the best capacitance,

Internal wiring
Van Dame 268-100-00 3.6 outer diamter. 47pf/m core to core 152pf core to sheild.

Mogami 2497 looks familar to the old atlas cables i had once
Mogami 3159, 2803, 2944, 2965/4
You are correct. The capacitance should be 30pf/foot or less, so you can have 100pf or less for the total length. This is particularly important for MM cartridges where the inductance is higher, associated with the higher output.

For LOMC cartridges its still important because the capacitance is in parallel with the inductance of the cartridge, forming an electrical resonance that can be anywhere from 100KHz to 5MHz. when this resonance goes into excitation, Radio Frequency Interference is thus generated and injected directly into the input of the phono preamp. The higher the frequency the greater the possibility that the phono preamp's input can reject it. Many phono section designers seem to ignore or are ignorant of this phenomena; their products thus require a 'cartridge loading' resistor at their inputs, but as you can see now the resistor is really for the benefit of the phono section as it detunes that resonance, and in so doing prevents the RFI.
 

AMR / iFi audio

Industry Expert
Aug 21, 2019
2,636
1,153
260
43
UK
ifi-audio.com
super explained, in addition, certain cantilever materials + stylus also have resonance .
exsampe emt tsd 15 adds a calculated capacitor to smooth them out no treble rise or resonance these can even be in the low range 15kh-70khz.
Unfortunately, not every manufacturer eliminates this resonance.
after then absolutely straight frequency response in the audible range. Sorry for offtopic
View attachment 99135
Very interesting info. That looks like an older cartridge. I would recommend replacing this capacitor with something from current production. The older type of ceramic capacitors is really non-linear. My recommendation is C0G/NP0 dielectric from a reputable manufacturer like Vishay, Kemet, or others.
 

thekong

Well-Known Member
May 10, 2012
246
135
948
You are correct. The capacitance should be 30pf/foot or less, so you can have 100pf or less for the total length. This is particularly important for MM cartridges where the inductance is higher, associated with the higher output.

For LOMC cartridges its still important because the capacitance is in parallel with the inductance of the cartridge, forming an electrical resonance that can be anywhere from 100KHz to 5MHz. when this resonance goes into excitation, Radio Frequency Interference is thus generated and injected directly into the input of the phono preamp. The higher the frequency the greater the possibility that the phono preamp's input can reject it. Many phono section designers seem to ignore or are ignorant of this phenomena; their products thus require a 'cartridge loading' resistor at their inputs, but as you can see now the resistor is really for the benefit of the phono section as it detunes that resonance, and in so doing prevents the RFI.
Hi Ralph, so what is the maximum capacitance you think is acceptable for a phono cable (the whole cable, no matter what length), specifically a RCA terminated one for MC cartridges if it makes a difference ?

I have posted the capacitance measurements of a Gotham cable above, but they have listed 4 different capacitance measurements, so which figure should I go by?

Thanks
 

DasguteOhr

Well-Known Member
Sep 26, 2013
2,354
2,515
645
Germany
Cardas does a lot good phono cables, internal wiring tonearms and phono to preamp.very good sound never felt as limiting. copper cable low capacitance.
 

AMR / iFi audio

Industry Expert
Aug 21, 2019
2,636
1,153
260
43
UK
ifi-audio.com
Cardas does a lot good phono cables, internal wiring tonearms and phono to preamp.very good sound never felt as limiting. copper cable low capacitance.
Agreed, they are great in brighter-sounding setups. I had a Pro-Ject Derbut with tonearm rewired with their cable. Great quality-to-cost ratio.
 
  • Like
Reactions: DasguteOhr

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing