Best resistors for use in phono stage?

Vishay. The standard for audio for decades.

Thanks. Is there an audible difference between metal or carbon film? If so which type is preferable?

In your application, the loading resistor is acting as a voltage divider which, given its high resistance, mean that only a small portion of the signal is going through the resistor and being burned off as heat.  It is not a critical part whose quality will matter greatly.  Is it still worthwhile to seek the best?  Probably, because everything matters.  What is then, is the best?  That is harder to know because “best” is always a matter of specific application and personal taste.  I know a number of builders who dislike the sound of quite expensive Vishay resistors, finding them to be “dry” and lacking in harmonic richness.  I had a linestage, which I liked, that extensively used Vishays, so it is a matter of taste and application.  The company that consistently produces very good components—Audio Note—makes some pricey Tantalum and Niobium resisters that I would bet sound good if you don’t mind spending something like $40 per resistor.

Appreciate that response @larryi .

@slaw

Check the Charcroft Z foils, if for mc loading, better than Vishay naked Z foils.

I would expect that your phono stage does not require more than 0,4W for those locations.

Thanks @petg60 

I bought a set of el-cheapo resistors from Amazon (but still having tight tolerance), which I use for cartridge loading. As stated previously,  the signal headed to your speakers does not actually pass through the load resistors.  Anyway, I can't be confident that I have achieved the best sound possible,  but what I can say is that with these resistors,  my analog front end sounds head-and-shoulders above my Aurender A10 digital front end, and that's with pretty heavy loading (currently 22 ohms).

Interesting @woofhaven1992 .

I seem to be getting differing view points. I was hoping to get a concencous opinion. Maybe it's too subjective. I would've thought the music signal went through the loading resistors.

@woofhaven1992 ​​​​​​, shunt or series have the same effect on sound.

What passes through the loading resistor is current, as basically it is placed across cartridge's output terminals, so the resistor quality would have an influence.

What passes through the loading resister goes to ground.  The signal going to the rest of the phono stage does not pass through this resistor.  Can it still affect the sound?  I don’t know for certain, but, I suspect that it matters, but it is not as critical as other components more directly in the signal path.

Nice info. This is the sort of discussion I was hoping for.

I’m confused as a novice, if what passes through the resistor goes to ground, how do resistor values affect SQ? IE: cartridge performance?

I’m confused as a novice, if what passes through the resistor goes to ground, how do resistor values affect SQ? IE: cartridge performance?

To an extent what is going to ground is pulling down the signal that to going to the phono stage.

So it doesn’t matter if it is in series or shunting, if the resistor were a flickering switch you still get flicking levels coming out of the phono stage.

I think I see. Thanks!

Great explanation! Thanks.

Depending how much wattage ,Vishay naked are top notch if 1/2watt or less 

What makes wattage a challenge?

a bunch of people seem to be missing how electronics work. While the signal may not pass in one end and out of the other of these resistors, the music signal --  subsequently amplified -- voltage is sensed (dropped) across them. Any nonlinearity or noise will be amplified.  They are in fact very, very critical.

That said, most resistors are excellent . Buy 1% metal film.  I have seen extensive listening tests of various compositions and brands, and at the end of the day its a bunch of trade-offs. So my "best" might not be your "best".

The Dale RN55 and RN60s are mil spec and excellent; a step up are Vishay branded and above that Caddock bulk metal.

I frankly use respect names tat in wholesale i get for /10-1/20th the cost of even the Dales. That said, the first stages of MC are the one place i might just pry my wallet open and spend a but more.  The most critical number are TC and Noise.

I have built nearly a dozen variations of prototypes MC RIAA stages over the past 2.5 years and the design has always been vastly more impactful than brand X vs brand Y of resistor.

G

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

This is fascinating.  So, question: in a setup that is not using balanced signals fron the tonearm to the preamp, is there a distinction between the ground and the negative lead?

I ask because I may have screwed something up. I have set up my load resistors at the back of my turntable, but currently they run from the positive to the negative leads of each channel, rather than positive to ground.

And I have been convinced by this discussion, by the way, to grab some Vishay resistors for this application.  I can't wait to hear what that does.

Vishay makes a lot of different resistor types ranging from cheap generic resistors to expensive Z-foils (they may have even more expensive ones that I'm not familiar with). 
 

I have used Z-foils (both Vishay and Charcroft which sound very similar to me) as well as Audio Note non-magnetic Tantalums (mostly the silver version). These are excellent resistors with a clear (to me) advantage in SQ over more generic offerings. I think the Z-foils are a bit more transparent and the Tantalums are a bit richer sounding. 

The AN Tantalums are available in a wider range of values and higher power ratings, so I've generally used these in my tube projects. 

@woofhaven1992

hmmm, why does your tag not come up and why wont it tag you if i type it?  oh well.

If the phono preamp is single ended (not balanced/differential) then "negative" will be grounded at the circuit board. SO no, there is no difference.

In a balanced system there are two approaches:

load across the two leads

two loads, each 1/2 value, from each input to ground (so full load across balanced inputs, but the center connected to ground)

G

@itsjustme thanks...I think I'll leave my setup as is since it makes no difference with my Sp14 preamp and also because I'm a significant danger to my equipment when I use a soldering iron, which, by the way, is why I have the resistors installed on the back of my tonearm rather than on the circuit board.

What passes through the loading resister goes to ground.  The signal going to the rest of the phono stage does not pass through this resistor.

Incorrect. Ground is a reference to the Earth Safety. Zero Volts Audio (0vA) is the signal reference. 0vA may not be Earth referenced.

The current is equal in all parts of a circuit. Basic Ohm's Law.

If one sets the reference to the audio signal line, 0vA will show the inverse signal.

This is a good discussion.  

Some have mentioned a favorite for tube equipment. My phono stage is SS, my amps are tube, if that matters.

Vishay Z foils aka Texas Components TX2575 highest resolving, transparent I've used, I don't really hear a specific sound quality from these, consider them neutral. Takman carbon film when I'm looking for a bit of warmth. I'd like to try some of the AN in my next project.

Vishays can be stacked if more wattage needed, gets pretty pricey here.

Wattage. What's the importance of this?

For your purpose—cartridge loading, the lowest wattage resistor will be WAY more than you need because very little power is passing through it.  You can use the lowest rated resistor you can find.

Larryi is right.

All components have sonic signatures. Whether a particular part is suited to a system can only be evaluated in situ.

Beware of FanBoy recommendations.

My opinions are based on solid state in a vinyl / ESL system. The Vishay VAR series are rated at 300 V if  IIRC, so they are suitable for any place in the amp (unless you are driving ESL's directly). IMO, VAR are better than any of the Caddock resistors that I tried: less edge, more clarity. Clearer than Mills WW.

@ieales  points out that all components have sonic signatures. That is absolutely correct. That certainly includes the resistors, capacitors, and transistors elsewhere in the chain. But this is a very good time to determine what you like, so that you can, in time, get more of it. I would definitely buy two Vishay VAR and two AudioNote to audition - that's how I started on the DIY road.

Good luck!

One must be aware of "too much of a good thing". Depending on the equipment replacing all the Brand X parts with Brand Y may not yield the anticipated results.

What many fail to realize is an 'amplifier’, be it phono, line or power, circuitry is essentially a power supply regulator. Sadly many power supplies have very poor impedance vs frequency characteristics. The ubiquitous three terminal regulators in much of today’s equipment have vastly different impedance characteristics between the VCC and VEE models. Gross differences exist between the same 78xx part from divers manufacturers. One of the most astounding sonic improvements I ever experienced was linearizing the ± analog and 5VDC digital power supplies impedances in a CD player. I felt like I had been transported back to the control room and listening to the master 2T feed with a 2KW/ch amp stack.

Make haste slowly.

Three terminal regulators - how true. I burned the better part of a day last month on a circuit that wouldn't behave, only because a 7806 failed in a highly non-linear way. Name brand device, too.

@slaw

This is what you need. I used these in all my phono amps

typo: 1kw/ch 😕

2x 300w for dual woofers

1x 200w for mid

1x 200w for tweet

Three terminal regulators - how true.

An engineer who once worked for me and is now a big shot @ AD says ’brand name’ is no longer a guarantee unless you can prove the provenance. AD will no longer accept ’failed’ parts without a paper trail.

It’s a sad state of affairs where the local electronics stores no longer exist and you have to buy from the bigs to ensure you get what you want.

@noromance , 

Your link didn't appear.

@slaw I hyperlinked the word "This"

Link all components, the Vishay foil have a 'sound' due to the leaded construction inductance. I question the use of 'naked' foils other than for cachet as they are subject to both mechanical and environmental conditions.

Fanatical resistor precision is swamped by capacitor tolerances which are orders of magnitude larger.

Z-Foil Datasheet

That's quite true, but I am convinced that much of what we listen to is dielectric absorption, or DA. This seems to be minimal in five components: bare wire, vacuum caps, air gap caps, nichrome wire resistors, and slightly behind these, Vishay VAR.

Also, you can get exceedingly close to exact RC values by measuring capacitance and then specifying the resistance to high precision, which Vishay's Advanced Products Division (or whatever it's called now) will manufacture to your spec for a small fee. But it's rare to have an application which is critical to even 1%.

Anyway, Vishay is one fine company to deal with, unlike some others I won't name.

"hoping to get a consensus opinion".  LOL.  

Fanatical resistor precision is swamped by capacitor tolerances which are orders of magnitude larger.

Just a general note for all (not aimed at the above poster, but that some may use such missives to dismiss):

That is indeed true but it does not mean that a decent quality trained ear can’t hear the differences in resistor qualities in a well executed circuit. so the idea of swamping does not hold true.

Iffin’ you can hear a voice in a room at a party, with huge amounts of background noise..which just about every person in existence can do, then the idea that the resistor qualities are swamped by capacitor distortions is on shaky ground.

We can suss out, we can separate it out, we do it every day in all our senses, in ways and levels and complex methods, etc..that the vast number of people are wholly unaware of, even though it is part of every millisecond of their biological and complex highly filtered and separated out life..

Realistically, very very few people understand their senses or their minds, or self. Projection is the norm - projection out of the given box.

I read an article just the other day on the cilia of the ear and when we age they get to being impacted with one another, physically, so that is apparently the source of how some can’t separate out complex sounds, whereas others can. Some have different ears, physically different and more capable ears than others. ears are individual, like mental capacities.

One persons ear-Q is not another's Ear-Q, and the same for the given processing intellect, so it is unwise to make assumptions about self and impress such upon another.

thanks.

That is indeed true but it does not mean that a decent quality trained ear can’t hear the differences in resistor qualities in a well executed circuit. so the idea of swamping does not hold true.

Apples and oranges. As stated previously everything has a sonic signature and everything interacts. Agreed that not all can hear signatures.

Unless one matches capacitors or matches resistors to measured C, there are audible deltas that some may misattribute to component rather than FR errors. A single 5% part at its ± value extremes yields ≈1.9 and 2.1. Such deltas are readily audible in the critical 2-5kHz region.

Some manufacturers go to such lengths to match values so the product matches the spec. One was Spica. When I rebuilt my TC-50 XO, I measured the drivers, inductors and resistors and then selected capacitors to match specification as closely as possible. The imaging improvement was astounding relative to the aged originals, all of which still measured within their tolerance. We could debate the contribution of replacing EL & Mylar w PP vs. tolerance compensation.

Bottom line:  E V E R Y T H I N G  matters

Thanks for everyone's participation. I ordered some Vishay 390 & 1000 ohm to try. I have a factory slot for 980 ohm. This should get me started.

I think you should also order a variety of other values, just to try different degrees of loading.  You could buy cheap resistors for the basic experiment before buying pricier models.  With some cartridges, there will be not much difference between 390 and 1000 or even 47,000 ohms--these all represent somewhat low amount of loading.  Resistors in the 125-150 ohm range and perhaps one with as low a value as 50 ohms would let you see what much more loading does to the sound (the lower the value the higher the loading).  

@larryi , 

As far as values go, I'm going by my experience with my other phono preamp and what Peter recommends for the Sussurro. I had always been satisfied with 390 ohms with my other phono preamp. My feeling upon hearing my current 400 ohm resistor is that I'm very close. Satisfying my curiosity with what I've experienced and what Peter recommends.

BTW values are entirely dependent on the specific cartridge; you are creating the load which interacts with the reactive components of that particular cartridge, windings, etc to produce the most linear output. It has (almost) nothign to do with the phono stage