Top resistors


Many threads with opinions on boutique coupling capacitors, but very little consolidated information on the sonics of resistors. Anyone care to share their thoughts on the attributes of their favorite brands & types for specific tube and SS applications? How much of a difference does a good resistor make?

My interest in the topic increased after recently installing the latest Texas Components nude Vishay TX2575 in several SS and tube phono & LS components. This was a proverbial "Ah-ha" moment-- a stray resistor dropped into signal path here or there, surprising with an improvement that equalled or surpassed the impact of a switch to a top coupling cap like V-Cap or Mundorf.
dgarretson
I've been waiting since this thread was revived for someone to suggest Abbie Hoffman as 'top resistor'.
Reb1208, thanks very much for the follow up. My hat's off to you for the diligence you've put into the evaluation!
I have used the Vishay bulk foil for years, in both tube and SS gear. They add no character of their own to the sound. If a user installs them and finds them bright, all the Vishays are doing is letting through the sonics of that circuitry or device. Using carbons is a band-aid for a different problem. You have never heard LP playback unless you have listened to a phono stage all done with vishays. see link below. best.

http://www.vishaypg.com/docs/49997/49997.pdf
Johnss: Which Vishay bulk foil are you referring to?

The Vishay S102C (non nude version) I tried in the signal path in a direct coupled position between amplification stages. This resistor is highly colored in that it strips music of harmonics resulting in a tonally inaccurate sound. The Vishay (TC) TX2575 is much more tonally accurate , harmonics are presented intact. The sound of a maraca sounds like a percussion instrument through a TX2575. Through a S102 (non nude) it sounds like gravel inside a soda can.
Vishay VSRs.

Similar to the S104.
the biggest improvement are the shunt resistors (47K, 100K etc) where they are loading the output of one of the stages.

http://www.datasheetcatalog.org/datasheet/vishay/vsr.pdf

Also keep in mind they will let through what ever is in the signal path, so if you are using in SS gear, you likely will need to add bypass caps to the power supply if not already there.
I haven't done any experimentation myself, but, I know people, including small manufacturers of ultra high quality components, who say there is no such thing as a best or top resistor, capacitor, or any such component. I asked one why he worried about a certain "cheap" resistor becoming unavailable, and he said that he had tried many others, such as Vishay 102Cs, and for his circuit, in his opinion, they sounded dry and analytical. I heard the same from another small manufacturer.

It would be much easier if there were such a thing as a clear upgrade path, but, that is not the case. I heard an "upgraded" version of an amp I am familiar with that sounded shockingly bad compared to the original. It turned out that the upgrade consisted of just parts substitutions of Black Gate caps for the cheaper caps the manufacturer used. In this particular application, the Black Gates were NOT appropriate.
I built my Hagerman step up using basic bulk Vishays. There are only 2 resistor locations directly in the signal path. With the basic Vishays the sound was good, but not as transparent as I had hoped. I tried the (very expensive) nude Vishays in those 2 locations and things opened up dramatically. Maybe too much.

I then put a Riken Ohm into the second location, leaving the nude Vishay in the first, and it warmed things up nicely without losing that transparency.

As it turned out my cartridge loads as 220 ohms, which was the value of that second nude Vishay that I replaced with the Riken. So I replaced that loading resistor with the nude Vishay and got another leap in transparency, even though it was not directly in the signal chain.

So I have found that resistors do in fact play a role to tune the sound in a sensitive circuit. I have also found that those white paddle Caddocks are very nice, though also very expensive. Used judiciously for tuning these can be a great improvement, but they are far too expensive to use everywhere.
you'll get the biggest bang for the buck using them in the shunt positions or interstage loading points. If you really want to hear what they sound like, solder an RCA on each end and instert in a length of interconnect betwen a source and pre amp.

dont forget, as the level of the noise floor is reduced, any low level details will come through (good or bad). These are among the quietest (lowest noise) resistors available.

best
The dissing of the Vishay S102 by Reb1208 is rediculous. This resistor is extreamly clear, smooth with a slightly sweet treble. To say it sounds like gravel inside a soda can negates anything this person says about anything that pertains to sound perception. Tweaker
I haven't done any resistor rolling myself, but, I once spoke to the designer/builder of amps and preamps who did not like the S102 for his designs. He found the resulting sound to be lean and seemingly stripped of harmonics. He was quite clear that the right parts in any design has nothing to do with cost, reputation, or any kind of judgment of intrinsic quality--it is a matter of specific voicing. For the same reason, he liked a particular conductive plastic Alps potentiometer that he could no longer easily find even though he could easily replace it with much more expensive alternatives and pass along the cost (he builds quite high end designs); he said he would gladly pay much more for that "cheap" part which was no longer being made.
if a person installs the Vishays and hears too lean a sound, you are hearing what the circuit is really doing. hard to argue with a 30 db improvement in signal to noise. The main purpose of using vishay is to get a blacker background.

I have re-wroked 5 pre amps of diffrent makes with vishays resistors and have always had stunning results.

Also agree the older copper end cap HOlcos are great for warming up a lean sounding SS amp or pre amp. Also dont forget the PS filter caps are in the signal path, so if you have not added any bypasses on those big caps, you are listening to the sound of the filter caps too.

happy soldering.
There is always a way to balance things out. I tried some of the nude Vishay's in my phono stage and found them to be incredibly transparent. However, I did wind up removing one and replacing it with a Carbon type that makes things more musical to my ear. The combo is perfect to me, where just using one in both locations was too much of a good thing one way or another.

Voicing!
From what I have read it is a good practise to not use just one brand of resistor in your project. The result could start to sound too much like that resistor.

A hint that a friend sent me about Alen-Bradley carbon resistors: bake them at 180 degrees for eight hours and then shallac them once they are cool. This should reduce their noise and help them hold their value.
Yo Johnss, Since it seems that you can hear do you have a preference for a particular metal film or other type of resistor that aproaches the clear , accurate sound of the S102 that isn't bright?? I thought I was hard to please, man if you can't like the S102... The only thing I can fault them with is the price. Not perfect but awfull nice! Thanks, Tweaker
Tweaker, the S102C (non nude) shows its weakness when compared to the TC TX2575. I suggest you re-read what I wrote and do the experiment for yourself. Taking cheap shots at other posters just shows your insecurities.
Gravel inside a soda can?? Yea I'm insecure. Who else out there thinks that the S102 sounds like gravel inside a soda can?? If your out there send me a couple of 3.3k's before you through them in the trash(where they belong, of course). Tweaker
Johnss, I love the S102. Can you suggest a reasonably priced resistor that comes close?? So many out there these days. Thanks, Tweaker
Naked vishay( bulk foil $13) very transparent, detail, and super quiet. Very good on solid state signal path. Riken carbon composit: is very musical, warm sounding, good for tube amp. If you are going to uo grade for tube gear go with Riken. You can not go wrong. The bigger the wattage the better you will get out of resistors. Audionote tantulum carbon composit: one of the best resistor imho. Very natural sounding, super warm, pleasant sounding. Very good for tube gear. In all this is my favorite as for upgrades on tube application. As stated the higher the wattage the better result.
I have been using Allen Bradley 2watt 1k for the Cathode resistor. (R6 on the Joe Roberts 91a Schematic).

A friend lent me 2 watt AN tantalums. Wow the detail is addictive..really natural, warm and beautiful. The only problem in my particular system was along with the detail came too much emphasis in high frequencies. A certain crispness that seemed unnatural. Again, it may be related to my particular amp, etc. I am in contact with Michael at Percy for resistor suggestions. May try the TX2575 based on all the good reports in this thread.
Jetrexpro, What type of resistor did you replace with the tantalums? I have gradually switched a number of resistors in my system over to 2w AN tantalums, and I have been very pleased with the improvements in sound. The AN does have a warm, solid bass and lower midrange, so my findings match yours there. However, I would never describe their HFs as crisp. If anything the highs, in my experience, have been slightly soft and even a bit rolled off. That hasn't been an issue with my system but again I find it hard to understand how they could be considered crisp unless your previous resistor was something really dark and dull sounding.

While I don't agree with a number of things stated by others in this thread, it is a welcome change to see resistors discussed in a similar way as capacitors. Over the years, I have found resistor swapping to be nearly as important sonically as capacitor swapping. Having the right mix of resistors and capacitors is absolutely essential in my opinion for achieving the right tonal balance and optimizing dynamics.
Salectric,

I put the A-B's back in after trying the tants. I dont understand it either but the high frequency emphasis was undeniable. That is why I mentioned in my post that it could be something peculiar in my system. For instance, I pulled the capacitor that is bypassing this resistor completely out of the circuit. I also took the grid cap off of the 6C6 driver tube and have 22 gauge silver wire directly in contact with the grid. Not sure if any of these things were interfering with the sound of the Tants, but I can't be sure. I am awaiting a response from Percy Audio as to another resistor recommendation.
Jetrexpro, Were the tantalums the newer type made by Audio Note during the last few years, or were they the older style Shinto tantalums distributed under the AN name? I tried the old AN tants 10 or 12 years ago, and they had a peak in the midtreble and were slightly edgy. The newer AN tants are much more neutral in my opinion.

Of course, AB carbons are very warm and could be considered dull in the highs, so perhaps nearly any modern resistor will sound bright in comparison.
And perhaps I have been over compensating for the warm A-B's by doing things like removing the grid caps. I will check with the guy who lent me the Tants to see how old they are. I do know they were fully broken in since he had been using them in his home brew 2A3 amp.
The AN Tants I borrowed are the previous version of the AN type; Audio Note is now making a newer version with non-magnetic copper end caps.

I am going to get the TX2575 and be mindful that if I hear too much hi end emphasis there may be something else in my amp/system to blame
Prcinka, Cant find much info on how the Amtrans AMRG sound. Can you shed some light?
I have tried AMRG carbon films 3 times---as the cathode resistor in my linestage and as dropping resistors in my power amps' bias supply. Each time the ARMG was heavy in the bass and very dark and soft in the highs. In each case, I ended up replacing the AMRG with an AN tantalum 2w which solved the coloration problem.

I have heard the AMRG is billed as better sounding than the Riken carbon film. I haven't compared them in an A/B test, but they certainly sound similar. For some reason, Rikens seem to do very well as gridstoppers which is how I use them, but in my opinion they are too colored in other spots.
The Vishays arrived and I installed them in the 6C6 cathode position. Will report back in a week after some burn in time
In the past I have built bridges made up of many Vishay resistors for replacement of high wattage resistors in loudspeakers..Upon first hearing this change out tears may arrive in your eyes.

All those engineers and designers who say there are no differences in these parts either have a problem hearing the truth for themselves, never listen to a simple part swap out or just sell their product based on external appeal. Tom
The Vishays arrived and I installed them in the 6C6 cathode position. Will report back in a week after some burn in time
After 60 hours the the Vishay TX2575 are starting to sound really nice. That crispness that the AN Tants had in the hi frequenies that was bothering me is not present in the Vishays. The high end seems very natural. So far there is richness, natural detail and some soundstage depth. I do notice paticularly how natural they sound. Very satisfying in that regard. They need to develope more front to back depth for me to be completely happy.

Before 60 hours, they sounded sterile and intruments didnt have their individual tonal characteristics. The soundstage lacked the depth and richness of both the AN Tants and A-Bs. I was not loving the sound at all. Sound stage was flat and uninteresting.

So far so good. More in a few days.
There is a lot to consider in my opinion when choosing resistors. Is much more than just making sure they will handle the power.
When it comes to noise, there is nothing better than high quality wirewounds such as Dale RS or Mills. You also want to use a larger physical size in areas that can be prone to noise. No problem using a 5 watt where a 1 watt would work. It can make a difference.
There are certain applications where a certain type of resistor is better suited. Unless going for a vintage sound, I stay away from carbon comps anymore. They are just not reliable enough and can drift in many applications. I wont even use them at grid stops.
There are some very good metal films available today as well as some decent carbon films.
Resistors can make a sonic difference depending on how and where they are used. I would certainly not used sand cast resistors in the signal path just as I wouldn't place a carbon comp in the power supply.
Sorry for late response, but I like the AMRG in my active crossover....to the debate on coloration, you have to try to hear for yourself.....especially if you find the AN tantalum to have none....
Every time I have changed the 6C6 cathode resistor I have heard a sonic difference and it is not subtle. This is a single ended amp with a low parts count. When I pulled the bypass capacitor that made made a dramatic difference in sound as well as the gain of the amp. Response34, I will look into the possibility of replacing the 91k A-B's with 91k/12watt Mills resistors. This is the 6C6 plate resistor and audio signal is present here. For now I am happy with the overall sound of the amp.

After 100 hours the TX2757 are here to stay. They let the music pass thru with richness, clarity and depth. No hi end emphasis or etch. Each instrument has its own accurate color and detail but not at the expense of the overall musical message. Front to back depth is very pleasing and I am not missing the A-B's or the AN Tantalums.
After a month with the TX2757 in the 6C6 cathode position, including bypassing them with Black Gate Caps I decided to pull these resistors. They did not provide the richness and room filling sound that the A-B's and the older AN Tantalum did. A few weeks ago I got two of the most recent production 1k An Tants from the Hi Fi Collective.

These new Tants are more closely akin to the A-B's than to the TX2575's. They are not as sonically accurate or pure as the TX's. But they do fill the room with rich satisfying music like the A-Bs but with more detail and without the extra noise or warmth or whatever it is with the A-B carbon comps. Still running the amp without the 6C6 bypass cap.
Very interesting comments. I have tried in a DHT preamp the Audio Note, Shinkoh, Takman, Riken and Amtran resistors. They all sound different. I prefer the Shinkoh for a more realistic and natural. The metal film was more lively and open compared to the Shinkoh. Second to the Shinkoh was the Audio Note, very close but not as natural in tone or flesh sounding. I am able to switch the resistors on the fly as I built them into a rotary switch. Many people who have heard the preamp in "their" system agreed to my findings even though they did not know what resistor I was switching to. Not sure if I would get the same results in speakers or amplifiers as I have not tried this yet.

Happy Listening.
Bigkidz,

That rotary switch is great idea and thus provides instant results. Nice! I will have to try the Shinkoh's when I begin to "voice" my newly built phono pre.

It's good to keep in mind that I/all of us have different ears and listening priorities. I am voicing my amp to work with my sources and speakers in my room without a preamp.
It must be very difficult for the professional builder to voice an amp or preamp with so many variables to confront. I have been voicing my amp slowly for about a year.
Interesting comments Jetrexpro. It goes to show that longterm reactions are what matters, not quick conclusions after just a few hours. Thanks for sharing.
While my experience with Vishays is limited to the regular series, both nude and otherwise, I have to say your comments are very similar to my reactions. Vishays can sound too cool, lacking in warmth and emotion. IMO, they have their place but need to be used sparingly. For instance, I only have one in my system right now---as the grid stopper on the input tube for my SE amps. It works great there and helps to offset a tendency towards excess warmth.
Salectric,

I put the Tants on my cap burner for two weeks before installing into the amp circuit but even after that, their sound has been changing over the past four days. Last night they were starting to sound luxurious and rich but still maintaining detail and without that crispy upper mid/hi frequency etch of the older Tants.

More later.
Hi Response34, I was going to use some Mills MRA-12 for the power supply and as possibly plate resistor for my tube amp. But the new Mills resistors are now produced in Mexico, no longer in USA. Someone told me there's been some problems with the Mills made in Mexico. Have you had any issue with the new Mills?
I have tried several resistors, some of them are best sounding for me and most of them sounds different if you change the dirrection on which you'll start the input signal.

Here's the result: (caution: quite long) :) and sorry if my english not really good

AUDIO RESISTOR COMPARISON SOUND AND DIRECTION TEST

TAKMAN REX – CARBON COMPOSITE
>>> Bit edgy and hard sound and less detail, less bold than Riken RN std in the same direction but more organized
<<< Sweeter, more detailed, more musical, more airy and bit more warm, tone more balanced and organized
DALE RN60 METAL FILM – MIL SPEC
>>> Quite neutral, detailed high and crisp, more bold sound than takman (or more like direct cable I guest), not as sweet as Takman but less edgy and breathe music more –strong bass also + bit hard if compare to direct straight wire (less liquid)
<<< Bit sweeter but less bold, airy too, clearer high bit, and more musical a bit, still have strong bass but little lean
RIKEN RMG – CARBON (I like this resistor when it compare to almost all this reviewed resistor except TX2575)
>>> Sweet and spacious sound, detailed and airy, good bass and warm mid – bit laidback compare to shinkoh
<<< As mentioned above but bit more musical, more breathe, but bit less definition and bit less dynamic
AUDIONOTE TANTALUM
>>> Sweet and musical, not as much air as Takman (in reverse direction), good bass – felt bit tubelike sound and midrange domination
<<< As mentioned above but bit less bass leading edge (I need more test on this)
RIKEN RN STANDARD (BROWN COATING AND NO GOLD PLATED)
>>> Bit sharp high, bit edgy / hard, but good definition
<<< Warmer sound and bit woolly bass, more musical and rich, staging more wider and deeper (also compare to Takman) – bit midrange domination
SHINKOH JAPANESSE TANTALUM
>>> Sweet, detailed and airy and have big dimension in sound stage, quite neutral sound and draw me to music deeper (I feel overdominate in midrange compare to Riken or other neutral sounding resistor and then I decided to remove it and substitute with neutral sounding resistor) + slightly thinner sound compare to straight wire but calm presentation and leaner bass.
<<< As mentionded above but bit warmer sound (coloration I think) and bit overdetail high (edgier)
MILLS WIREWOUND 5 WATT
>>> Neutral sound, airy and dynamic sound, but not as sweet as tants, leading edge also in good side
<<< Less definition a bit but seems sweeter a bit / warmer (need more test)
KIWAME CARBON 2 WATT
>>> Bit noisy and high more apparent, other are quite neutral (need more test)
<<< Bit sweet and detailed also more airy (need more test)
KOA METAL FILM
>>> Sound more like Dale RN60, detailed and airy, bit sweet also
<<< As mentioned above but less bass, bit bright side but not sharp (need more test)

VISHAY NAKED Z-FOIL TX2575 or Z201
>>> This is what I say about, almost perfect resistor, the sound is all you wish your audio equipments sounds, imidiate, harmonic detail, open, detail but not sharp high, great bass, musical, neutral and smooth mid but not overly sweet, great dynamic, clean sound and fast – Very Recommended for upgrading – the effect almost like you change standard capacitor with much better one. My only complain is it added bit bass to male and female vocal, makes it bit thick. I never try other direction since it says no direction because of laser etched foil technology is almos equal on both side.
AMTRANS AMRG 2W CARBON RESISTOR
>>> Compare to riken RMG – this resistor bit more open and more neutral but less lusher. Better in music description and more musical compare to dale metal film. For musical taste I like riken than this amtrans.
<<< Less neutral and less lusher (bit forward)
How are you determining the directionality of a resistor? I have never heard of anyone doing this. Please explain in detail. As far as I know, resistor are non- directional.
I've read somewhere of article about why the resistor have different characteristic when you fliped. It depends on material used and inductance etc...I forgot about the details but it makes sense to me. In that article there's also show measurement (in volt as I remembered) how different result when you flip the resistor.
For me I just test all resistor above with simply method..
I build diy interconnect with the clip attached on signal cable so I can insert the resistor between and test it.
The resistors I tested approximately close on value.
one of the article you can read here:

http://jimmyauw.com/2010/05/02/resistor-orientation-on-the-oscilloscope/

the other one...sorry I forgot... :)
This is sheer nonsense; the guy is simply misusing his scope - notice he's using a crocodile clip for one end and just the tip of the probe in the other. Because of the poor contact of the probe tip, he's going to get different results even if testing in the "same" direction. He's basically a fool of an engineer.
In what country is an, "alligator clip" referred to as a, "crocodile clip?" I'm guessing Oscilloscope is not your first language. The tip that is ATTACHED to the other lead of the resistor; is of the, "retractable hook" variety. They lock QUITE SECURELY onto whatever lead they are applied, and provide an excellent connection.
OK- In 40yrs of electronics; I've never heard the term, "Crocodile clip." Now- having looked it up, I suppose it was inevitable that someone would coin the phrase. The rest of my post stands pat.
Even in Australia where I come from - and where we have crocs, and not 'gators - these were known as "alligator clips".

The alligator has a rounded U-shaped snout whereas a crocodile has a narrower V-shaped snout. The clips more resemble an alligator's jaws.

Regards,
crocodile clip is chiefly British - http://en.wikipedia.org/wiki/Crocodile_clip

Moving on... it doesn't look to me the tip is attached to the lead, but I guess it could be; looks floating from this vantage point. Another interesting question is, why is he using the "alligator" clip in one but not the other; why wouldn't he be using the same thing on both ends.

More to the point though, do you really believe a resistor would truly measure differently based on "direction", as if it has some sort of partial diode effect? And the person who posted that link said it all made sense to him - what exactly made sense?