Longest interconnect

[Ant]

What would be the longest interconnect I could run from my phono stage to my pre before there is any degredation of quality?

I am thinking of having a move about in my room but the turntable cannot be moved.

 

[griffo104]

I use a 3 metre run of Krystal Kables Ultima i/c from the Dino+ to my Majik - no obvious loss of quality. I think it's more of a problem if you have a passive pre-amp where the length of the cable is more important (I think)

 

[Ant]

Thanks, thats part of the reason for the move about, I dont want my passive pre trying to drive long cable runs (or more accurately the stuff connected to the pre trying to drive long cables).

 

[cjr]

RCA 5m. After that its tatties. Preferably as short as possible with regard to a phono stage.

 

[Ant]

cjr wrote:

RCA 5m. After that its tatties. Preferably as short as possible with regard to a phono stage.

Why as short as possible with a phono stage?

 

[cjr]

Ant wrote:

cjr wrote:

RCA 5m. After that its tatties. Preferably as short as possible with regard to a phono stage.

Why as short as possible with a phono stage?

Eh because the output of the phono stage being very low compared to CD. Longer the length, even more loss of already weak signal. 1-5m should be fine, above that IME using louder sources than phono stages – it meant me having to increase volume on amplifier.

 

[Ant]

cjr wrote:

Ant wrote:

cjr wrote:

RCA 5m. After that its tatties. Preferably as short as possible with regard to a phono stage.

Why as short as possible with a phono stage?

Eh because the output of the phono stage being very low compared to CD. Longer the length, even more loss of already weak signal. 1-5m should be fine, above that IME using louder sources than phono stages – it meant me having to increase volume on amplifier.

I had a feeling thats what you were getting at. So I checked the specs and the Phono stage puts out about 1 volt

 

[cjr]

1V 50% strength of CD RCA output which is generally 2V.

 

[griffo104]

Ant wrote:

cjr wrote:

Ant wrote:

cjr wrote:

RCA 5m. After that its tatties. Preferably as short as possible with regard to a phono stage.

Why as short as possible with a phono stage?

Eh because the output of the phono stage being very low compared to CD. Longer the length, even more loss of already weak signal. 1-5m should be fine, above that IME using louder sources than phono stages – it meant me having to increase volume on amplifier.

I had a feeling thats what you were getting at. So I checked the specs and the Phono stage puts out about 1 volt

CD players are anywhere from 2V to 6.5V (thinking of the old Helius players).

The Dino+ happily does 3m, it was a gamble when I did it but certainly there is no need to adjust volume when switching between sources.

I have too many components due to having 3 amps so need two racks - one gainst one wall, the other against the other wall at 90 degrees from the other rack.

 

[Ant]

I very much doubt the CD player puts out 2 volts. whats the difference between 1 and 2 volts? 7db?

Anyway I reckon I could get away with two metres then.

 

[griffo104]

Ant wrote:

I very much doubt the CD player puts out 2 volts. whats the difference between 1 and 2 volts? 7db?Anyway I reckon I could get away with two metres then.

Ant,

Just checked the Linn Mimik cd player oweners manual from the Linn website (I use a Mimik) and the output level is 2.0v rms (unless I'm looking at the wrong thing ????).

 

[Ant]

Sorry I meant I doubt MY cd player puts out 2 volts

 

[griffo104]

Ant wrote:

Sorry I meant I doubt MY cd player puts out 2 volts

oh

Somewhere up home I've got a 3m run of some cheap QED interconnect which is no longer used due to the Ultima. I could slap it in the post to you and you could give it a try without the need to move anything around.

 

[kennyk]

the problem is not the voltage per se, rather the output impedance of the phono stage. I don't think that phonostages are a lot lower in output than cdplayers. line level 'standard' is 775mV anyway. though many seem to be around 1-2V

I run 3.5m cable from my tonearm to my phonostage and 0.5m from my phonostage to my pre amp. the output impedance of the phonostage is such that it would struggle to drive a long cable, whereas the cartridge has a better impedance for driving longer runs (in much the same way that microphones do. it's not uncommon for a stage mic to be connected to 100m of multicore before it gets to the desk. specs for a Shure SM58 Stage mic - output: 0.19mV, output impedance 150ohms. load 150ohms. specs for Goldiring Excel (my own) cart: output 0.5mV output impedance 8ohms, load >=100ohms )

it's this reason that makes Naim stuff particularly tricky to partner with cables, particuarly the amplifier output. due to the output toplology, certain cables characteristics (LCR) cause instability. instead of the usual zobel network arrangement they rely on the cable inductance.

so check your output impedance of the phonostage and cartridge. you might find, as I have, that a longer tonarm lead is the answer...

 

[Ant]

The output impedance, it is 680 Ohms down at 5Hz on the Era gold then starts getting lower, Mr Slee says it can drive 600 ohms though

 

[Davewhityetagain]

Ant wrote:

What would be the longest interconnect I could run from my phono stage to my pre before there is any degredation of quality?I am thinking of having a move about in my room but the turntable cannot be moved.

I use a 4 meter interconnect from my turntable to phono stage it was made for me by Flashback Sales its made of Van Damme cable and is good for the job cost about £25 delivered

a MM cable is ok to about 8 meters and MC about 4 max

 

[kennyk]

I'd say that the max length of the cable would be more dependent on the source output impedance. I reckcon that an MC with an output impedance of a few ohms would drive a longer cable than one with a few hundred ohms. as for 47k, I reckon 2-4 m would be your top whack.

if the phonostage output is 680R then you should get away with a long cable to your pre. However I'd recommend trying extending the tonarm cable as well to see which gives you the better result.