The Superline is obviously very, very sensitive as the gain is enormous, so if you have improve matters with better cable dressing then it was likely something associated with that. As you’ve found, a tiny bit of extra capacitance can sometimes work well too, but as you’ve done, I would try to get everything as good as possible without, before adding anything.
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Thanks Richard. I’ll continue testing today. Interestingly late last night I checked it and the noise was still there though not as loud as earlier in the day. Then this morning first thing it was quiet. Nothing had been touched in the meantime. Part of me wonders if it might be something to do with electrical noise from the mains which may vary at different times of the day. As I said the TTPS is plugged into the main house circuit rather than the dedicated hifi circuit.
Was that with the 1nF capacitance plug fitted?
It does sound like some kind of interference. Looking at ways to minimise that would be my first step, but ultimately extra capacitance may be the answer, depending on how it affects the overall sound.
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Yes I fitted the 1nf early afternoon yesterday and it’s remained in since then. Might it be worth putting the TTPS on the dedicated hifi circuit or is that something to be avoided at all costs?
How’s the power cable from the TTPS in relation to the phono leads? I found after I had moved my deck that the power cable had come closer to the phono arm leads and this had introduced some interference. Moving it back to how it had been dressed before improved it back to how it was before - totally quiet.
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Ok, when you remove the cartridge input to the phono amp, do you still hear the rumble?
The phono preamp is very sensitive and at night if the front end is acting as some sort of radio tuned circuit because a component has shifted tolerance, then you may hear a rumble (ie low frequency noise amplified) , where as in the day, especially morning you won’t.
Yesterday when I moved the input for the Superline from Aux 1 to AV I still heard the rumble through AV.
Since inserting the 1nf capacitance plug the noise is dramatically reduced and this morning it has been quiet. I’m playing Clapton unplugged (one of the best vinyl recordings I have) to see if there is any reduction in SQ with the 1nf on the Superline. So far it sounds as good as before.
Richard - the Rega reference power cable is the same distance from the RP10 phono leads as it’s always been so it would be strange if that had suddenly started causing some RF interference but I guess it’s possible.
I could swap the NAT01 PS with the TTPS to move it a bit further away I guess.
I had this with a planar 3 into arcam rphono
went downstairs from listening the night before to find a rumbly hum.
lots of fiddly around. In my case the rega phono plugs weren’t a really tight fit on to the phono stage. A very gentle squeeze with pliers on the rega phono plugs meant a tighter fit and clean sound.
Of course it could be something more complex
Yes the Rega plugs do need to be tightened very firmly into the Superline phono sockets. I’m pretty sure mine are but I’ll check again.
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Ok so you have confirmed it definitely coming from the phono preamp.
Out of interest what do you have carried in the white trunking?
The difference in performance between night and day does suggest you have inadvertently created some sort of tuned circuit perhaps resonant between 300 KHz to 1.5 MHz… . So usual culprits are poor grounding especially cartridge grounding and earthing or capacitors gone out of spec.
The reason I ask about trunking, is that if it’s broadband or Ethernet that could produce inter mods with your tuned circuit, creating an audible effect… (indeed I had something similar with an FM tuber many years back)
It is cat 5e cable in the trunking. I’ve had it there for years though?
Yeah… might be exacerbated if the phono stage is acting as a tuned circuit… but kind of feels unlikely, but you can always disconnect one end when you hear the rumble to see what happens…
However I suspect it’s a phono amp capacitor tolerance issue, cartridge grounding issue, or a slightly dirty connection somewhere in the cartridge pin to phono input chain.
Yes agree. It seems ok at the moment with the 1nf plug fitted but I’ll have a play around with it later this evening to see what happens. Thanks Simon
I suggest that you mute the amplifier and disconnect the Rega’s phono plugs from the Superline, reconnect, and repeat two or three times.
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