2. cables
  3. 137458-102228

System Cable Capacitance Question from a New Audiophile

Hey all, first discussion started here. I want to start off by saying that I have learned so much from reading these forums and that I appreciate the awesome collective knowledge that this community is comprised of.

I am a young audiophile transforming my system from an integrated peachtree nova 150 to separates. A little background, my speakers are kef LS50s, powered by a red dragon audio s500 power amp. I just removed my peachtree from the chain and inserted a humble schiit sys to use as a volume control directly into my s500 and the sound opened up significantly. I will upgrade the preamp eventually but am focusing elsewhere at this point.

I am not worried about the cable between the s500 and the sys, but the cables between the sys and my DAC/phono pre. My primary concern is choosing a cable that won't eliminate any of the high frequency audio information through the passive. Lets brake up the two sides of the system.

Digital: My DAC is a metrum amethyst which I was assured by metrum would output more than the specified voltage into my power amp so I am not worried there. However what are some general guidelines for the capacitance of a single ended cable? The run will be 1m.

Analogue: I have a rega planar 2 with a nagaoka mp200 cartridge running through a project tube box s. Any guidelines for the cable running from the phono pre to my sys?

Any help would be greatly appreciated. I have tried kimber PBJ cables and some morrow audio cables, so looking to keep the interconnect price under 300 each if I can. I would like to upgrade the rca connectors as I have found really great sonic improvement with doing that.

Thanks! 
ajnackman

Showing 4 responses by ajnackman

ajnackman OP
60 posts
 
I understand what you're saying. My system is currently working, I think my hesitation is from reading that cable capacitance can affect the sound of a system, especially when using a passive preamplifer. At the moment I am really happy with how the system sounds, just curious if there are any rule of thumb's with the passive. Thanks for the comment!
ajnackman OP
60 posts
 
Are there any recommendations for silver coated copper cable for phono/vs digital signals or RCA connectors pure copper vs silver? 
ajnackman OP
60 posts
 
Al - Thanks for taking the time to lay that all out there for me. It took me a while to find the input impedance of my amp. I came across a 6 moons review that claimed that it was 50 k ohms which is why I began experimenting with a passive pre. The pascal class D module has a low input impedance natively, however red dragon has a custom input stage that mediates this. I think that should be a high enough value to interact properly with the phono pre. I haven't directly compared the digital size of my system with the vinyl but that might be a good place to evaluate any low frequency roll-off.

I read somewhere that a TVC with a low setting on the volume knob results in lower output impedance. This would be reversed for a resistor based passive. Would it make sense to choose a type of preamp based on the interaction between your source and power amp (will the volume knob be in the low or high regions) or are other considerations more important?
ajnackman OP
60 posts
 
Al, thanks again for the explanation. I find the impedance interactions fascinating even if I do not completely understand them. I’ll read up on that link. I really like the clarity of passives but have concerns about the impedance swings having audible affects on the system.

Last night I was doing some critical listening with my Roomate and we both agreed that while using the sys, the most dynamic sound was when the volume was set under 35-40% on the knob. The system played much louder but micro dynamics in the music seemed to slowly roll off.

That being said, I’ve been trying to figure out which kind of passive volume control I want to implement as an upgrade to the sys. I came across the Tortuga L3.V25 which is an LDR device and lets the user calibrate the preamp and set specific output impedance to test for a value that works best in ones system. This seems like an interesting option.

I know this thread has deviated from the initial post, I should have perhaps clarified my initial point but sometimes you never know where these threads will go! Appreciate the time and thoughts Al.
More to discover