Best resistors for use in phono stage?

Hey Steve,

I always sought out "Kiwame" resistors for tube equipment. Very nice sounding (definitely not dry or sterile) to my ears.      

@itsjustme is absolutely right about how the loading resistor works. This is easy to see if you magnify the effect. Imagine a transistor across the signal line and ground, turning off and on. Then the signal would be grounded when the transistor was on, and unchanged when the transistor was off. Imagine this happening really fast, and you can imagine how distorted the sound would be.

I demonstrated the ’resistor effect’ to a highly expert electronics designer, who didn’t really believe that resistors could make a significant difference. I installed several different types of resistor in a selector switch, and he heard the differences as clearly as I did. Then he said, "Now, tell me what you really did." When I showed him the circuit, he was converted.

Bottom line: the most expensive MILSPEC at $40 sounded worst, the cheapest sounded second best. Best of all, by a considerable margin, was a Vishay resistor from the VAR series (aka Z-foil). These are the so-called ’nude Vishay’ resistors, so called because they are sold without the usual layers of guarding and insulating material. The resistors sound exceptionally clear and without coloration. I use NOTHING ELSE in my DIY preamp and amps. Even the volume control consists of a selector switch and 60 odd Vishay VAR resistors.

The downside is that they are VERY fragile. Upside: simply the best. Also sold as a TXCC product IIRC.

Good luck!.

Lots of recommendations but it comes down to how you want your system to sound.

So far the best sounding resistors to our ears are the Audio Note non-magnetic silver.  Then the AN copper.  Vishays are more dry sounding in comparison but very pen and clear.  They don't really add any body to the notes but may work best when paired with tube equipment.  Metals are not to our liking.  Amtrans are also nice sounding especially for the price.  Used to use Caddock but the Audio Notes were much better sounding to our ears.. You should try go up in value so for 1/2 watt go to 1watt, etc.

Happy Listening

Obviously Terry9 has way more experience listening to resistors than i do! Sadly, in commercial products "fragile" is a bad word.

Anyway, he also touched on the basics of how a typical RIAA phono stage is designed. Much of the circuit is irrelevant to this discussion, but what IS germane is:

1. For MC the gain will be between 60-70dB (1,000 X to 3,000 X)
2. All cartridges demand different loadings for optimal linearity (sound) and to a lesser degree for impedance matching (not true in the circuit i will now describe)

The input from a MC cartridge is fairly low impedance (high current, relatively) but a tiny voltage - typically maxing out at 1/2 of 1/1000th volts. Maxing mind you - if you want 60 dB of signal to noise from the cartridge, this means the lowest signal is 1000 X lower. Think about that for a moment.  To me, this is one of the two most challenging points to design in any audio chain since it must be so quiet and so linear.

Putting aside currently popular (and potentially excellent) transformers for the first stage, almost every RIAA phono stage begins with one or more amplifying devices, often in a balanced pair, with the signal (wires from c art) applied either across the differential input or from the single ended input to ground.

For duplicative redundancy, i'll repeat - the resistors in question go from the input (base, Gate,...) of these first devices to ground. They determine the linearity of the signal and the proper termination of the cartridge. Any deviation is applied directly to the input.

Until a voltage is generated across this/these resistors there is no signal, no sound. The sound that is amplified IS this voltage drop ( the "voltage divider" referenced above - that much was kinda true). This first stage amplifying device is either a bipolar transistor (BJT), a Field effect transistor (FET, whether MOS or Junction, who cares? at the moment?) or a Triode. In this application they can be made to work pretty much the same. Most designers will choose a FET or Triode since it has the highest input impedance and therefore the least loading effect. The divider, in this case, is 100% through the resistor. Let me repeat - 100% through the resistor, in the case of the BJT with a gain of 200X for laughs, maybe 99.99% through the resistor. THAT is where the signal first appears. Any distortion will be amplified. Any noise will be amplified (by 1000-3000 times, remember?)

So yea, it matters.

But back to the question - which sound best? Its obviously murky.

If you doubt there are differences, here’s a link to a guy who plotted the linearity. The website is not reader-friendly, but you can get the graphs and even the raw data.

BTW i have no idea whet that electrical engineer guy needed to be shown. Test equipment engineers sweat this stuff every day for the same reasons the OP asked his question. Its well known by really experienced, open minded (not turn-the-crank variety) engineers. Sadly, those are rare.

data and graphs on resistors here

G

Link to non-military Dale low noise resistors.

https://www.newark.com/c/passive-components/resistors-fixed-value/through-hole-resistors?st=dale%20cmf-60