6 minutes ago, andyr said:

You have the correct installation, here (edited slightly):

The difficulty is ... determining which end lead is connected to the outer foil, if the mfr hasn't bothered to provide an outer-foil marking. ☹️

In Mundorfs, it's simple. The outer foil is marked with a shorter leg. The side with the letter "M" in the Mundorf inscription is on the side.

7 hours ago, xinvisiblex said:

This is exactly what's been bothering me. I've been watching Stephe's videos, and in one I see this:

And in the next video, it's something like this.

As if it was changed later.

It >was< changed later. I originally installed this one cap with the outer foil connected to the tube, when the actual lower impedance connection is ground, so I changed the orientation. These film caps are NOT polarized, nothing bad will happen if they are installed "backwards" like would happen with an electrolytic cap. For noise rejection ideally you want to connect the outer foil to the lowest impedance connection, which on the other caps in this amp is "the direction of the signal path". This one cap I didn't think through fully on the initial installation of it, then later realized the ideal installation would be reversed.

Again NONE of these film caps have an actual polarity and will not be damaged nor damage anything in either orientation. The outer foil acts as a shield and can help reduce possible noise connecting it to the lowest impedance, which on a Mundorf cap is the end closest to the "M" in Mundorf.

I personally like the way the EVO aluminum oil sound better vs the silver gold version, but that's just my personal taste. I also dislike the sound of those larger copper foil caps, some people love them! It's all about personal preferences on cap choices.

6 hours ago, andyr said:

The difficulty is ... determining which end lead is connected to the outer foil, if the mfr hasn't bothered to provide an outer-foil marking. ☹️

On a Mundorf film cap, the end closest to the "M" on the printed lettering is the outer foil.

5 minutes ago, SkunkieDesigns said:

It >was< changed later. I originally installed this one cap with the outer foil connected to the tube, when the actual lower impedance connection is ground, so I changed the orientation. These film caps are NOT polarized, nothing bad will happen if they are installed "backwards" like would happen with an electrolytic cap. For noise rejection ideally you want to connect the outer foil to the lowest impedance connection, which on the other caps in this amp is "the direction of the signal path". This one cap I didn't think through fully on the initial installation of it, then later realized the ideal installation would be reversed.

Again NONE of these film caps have an actual polarity and will not be damaged nor damage anything in either orientation. The outer foil acts as a shield and can help reduce possible noise connecting it to the lowest impedance, which on a Mundorf cap is the end closest to the "M" in Mundorf.

I personally like the way the EVO aluminum oil sound better vs the silver gold version, but that's just my personal taste. I also dislike the sound of those larger copper foil caps, some people love them! It's all about personal preferences on cap choices.

Thank you very much Stephe for the detailed explanation.

Edited December 19, 2025Dec 19 by xinvisiblex

Has anyone found a more graduated volume remote control for the R8 yet ?

Do any of the learning remotes offer a gentler volume control ?

4 hours ago, Treerover said:

Has anyone found a more graduated volume remote control for the R8 yet ?

Do any of the learning remotes offer a gentler volume control ?

I once spoke with a specialist, and apparently it's not that simple. Apparently, the problem lies with the potentiometer, which has large jumps, not the remote. The potentiometer should be replaced with a more precise one. But then the problem arises: more precise potentiometers are larger, so mounting them can be problematic. They can take up too much space and might not fit. This requires some modifications and tinkering. So I gave up.

13 hours ago, andyr said:

The difficulty is ... determining which end lead is connected to the outer foil, if the mfr hasn't bothered to provide an outer-foil marking. ☹️

If not stated anywhere, I just email the maker, works for me :)

6 hours ago, Treerover said:

Has anyone found a more graduated volume remote control for the R8 yet ?

Do any of the learning remotes offer a gentler volume control ?

The Willsenton R8 uses an ALPS 100K ohm Potentiometer motorized RK16812MG dual Pot 3B taper volume RK16

which is readily found on eBay for under $20.

The image below shows the different tapers that the pot is supposed to be available with. The R8 uses the yellow "B" taper.

The ALPS 100K 4 gang Potentiometer motorised 15A logarithmic RK168 Pot looks like a fit but it does not show what the taper is. I tried looking for the 4B or 5B tapered pot but was unsuccessful.

Your best bet would probably be buying the Harrison Labs 12 dB RCA Line Level Audio Attenuators from Amazon for USD$40. You just insert them into the input jacks of the R8.

The drawback is that you will need a pair for every device plugged into the Wilsenton. They also come in 6dB and 3dB versions of you think 12dB is too aggressive (but the 3dB attenuator would be useless). Luckily for me, my Oppo BDP-95 Blu-Ray player has an adjustable output so I can tailor the output to the R8's hot inputs.

Edited December 20, 2025Dec 20 by jon96789

On 3/9/2025 at 4:56 AM, jon96789 said:

I am beginning to think the noisy volume pot issue on the R8 is somehow related to the 6SL7 tubes... Some 6SL7 tubes are dead silent and others generate noise when adjusting the volume. I also noticed that cleaning the tube pins seem to reduce or eliminate some or all the noise as well but the results are inconsistent, some tubes do not get quieter but others do. 

 

Maybe the owners with dead quiet amps were lucky to have tubes that are dead quiet, and others do not... Right now I am using a pair of Ken-Rad VT229s which is dead silent in the amplifier.  If I insert a different Ken-Rad VT229 in the circuit the volume pot noise rears it's ugly head.  Maybe some tubes are just noisy for some reason, new or old. or maybe the Willsenton is sensitive to certain noisy tubes. 

 

I'd say about half of my 6SL7 tubes are dead silent and the other half are noisy to some degree.  Have any of you encountered noisy volume pots after installing a different 6SL7/VT229 tube when the amplifier was dead quiet before?

 

I guess I have to face the fact that I have to live with this problem.

 

 

 

I sprayed my volume pot with switch cleaner and the problem disappeared . It’s creeping back after 3 months but nowhere near as badly .

9 hours ago, jon96789 said:

The Willsenton R8 uses an ALPS 100K ohm Potentiometer motorized RK16812MG dual Pot 3B taper volume RK16

which is readily found on eBay for under $20.

The image below shows the different tapers that the pot is supposed to be available with. The R8 uses the yellow "B" taper.

The ALPS 100K 4 gang Potentiometer motorised 15A logarithmic RK168 Pot looks like a fit but it does not show what the taper is. I tried looking for the 4B or 5B tapered pot but was unsuccessful.

Your best bet would probably be buying the Harrison Labs 12 dB RCA Line Level Audio Attenuators from Amazon for USD$40. You just insert them into the input jacks of the R8.

The drawback is that you will need a pair for every device plugged into the Wilsenton. They also come in 6dB and 3dB versions of you think 12dB is too aggressive (but the 3dB attenuator would be useless). Luckily for me, my Oppo BDP-95 Blu-Ray player has an adjustable output so I can tailor the output to the R8's hot inputs.

Thank you for such an insightful detailed reply . Regarding the attenuators , surely these would compromise the sound signature/transparency of the interconnect ?

3 hours ago, Treerover said:

I sprayed my volume pot with switch cleaner and the problem disappeared . It’s creeping back after 3 months but nowhere near as badly .

I have changed my volume pot twice with no luck... The noise remained. I also tried spraying the pot but it is actually hermetically sealed. There is no way of spraying the wipers of the pot without disassembling the pot itself but doing so results in the impossible task of reassembling the pot. I tried to do so and I could not get it back together properly.

Edited December 20, 2025Dec 20 by jon96789

30 minutes ago, jon96789 said:

I have changed my volume pot twice with no luck... The noise remained. I also tried spraying the pot but it is actually hermetically sealed. There is no way of spraying the wipers of the pot without disassembling the pot itself but doing so results in the impossible task of reassembling the pot. I tried to do so and I could not get it back together properly.

It honestly worked for me instantly . Just took the volume knob off, inserted the straw and a few squirts . Gone instantly

All I can say is that with some tubes, the volume knob is silent, and others it is quite noisy... If the volume pot was the culprit, then it would be noisy no matter what tube was installed. I replaced the volume pot twice with no improvement. Since I can replicate the issue with different tubes, that leads me to conclude that the tubes are the culprit... There is something in the design in the R8 that makes it sensitive to noisy tubes.

I have a MaxiPreamp II tube tester. I have now been testing my tubes for noise and the offending tubes all tested as being high in noise... The quiet tubes are the ones that test with a noise level of -80dB. Any higher noise level than that the volume pot gets noisy. Unfortunately, nearly all eBay sellers as well as vendors cannot or do not test for noise, only for gain or transconductance. I have bought some brand new production tubes that have tested noisy right out of the box.

Unfortunately, you have to test everything yourself. For example, I use a Lumin streamer, which I connect to the amplifier's pre-in, allowing me to control the volume through the streamer. I had the lower-end D2 model, and everything was fine, but I decided to upgrade to the higher-end T2 model (twice the price), and that's when the ground loop problem arose. Due to the increased pre-in sensitivity, the hum was very audible. It was impossible to use this input comfortably. Both streamers are made practically the same; the T2 has higher-quality components. The problem resolved itself when I replaced the Lumin's switching power supply with a linear one. Only then did the speakers become completely silent.

The main issue associated with any noise entering the input stage of the R8 is to do with the very high mu value of the 6SL7 being at 70. It is super sensitive to any noise entering the circuit (residual DC voltage, RF interference, etc.). A variance in tube make both vintage and modern versions will see the tube itself contributing to the problem.

There are some ways of trying to mitigate the noise but it requires exploring several options. One option that may work in part is to place a 10-22kohm carbon composite resistor between the pot and the grid of the 6SL7 in the first half. Also, you may wish to explore adding a big 0.22-0.47uF coupling cap in the same part of the circuit (pot to grid). Another option to consider is to reduce the impedance of the pot as far as permissible - for example, half or a quarter of the current value (100kohm to 50kohm to 25kohm). Invasive circuit work may see the pot skipping the input 6SL7 stage and re-introduced at the next stage. Alternatively the first half of the 6SL7 can be converted to a cathode follower.

The gain can be reduced at the first stage by considering two further options. The first involves playing around with a cathode bypass cap and tuning its value. The next option considers adding a plate to grid feedback resistor (470+ kohm).

The emerging question is how long is a piece of string and would anyone try all of these options to find out what really works. There is a lot of patience and experimenting needed here to collate the findings and determine what solution/s work best.

14 hours ago, xlr8or said:

The main issue associated with any noise entering the input stage of the R8 is to do with the very high mu value of the 6SL7 being at 70. It is super sensitive to any noise entering the circuit (residual DC voltage, RF interference, etc.). A variance in tube make both vintage and modern versions will see the tube itself contributing to the problem.

There are some ways of trying to mitigate the noise but it requires exploring several options.

The problem with trying to change this is: the circuit is designed as being direct coupled. The plate voltage of the voltage amp triode of the 6SL7 sets the bias into the grid of the following cathode follower 6SL7 triode. The voltage on the cathode of the 6SL7 sets the bias on the grid of the phase splitter 6SN7 triodes. Sure all this could be worked out to get a 6SN7 to work in place of the 6SL7, but it's not gonna just be a drop in replacement. I'll try to look at this next year and see what that would take, I don't have an R8 to play with. If anyone who is able to measure voltages and change parts wants to remotely work with me on this, PM me.

Hello. I have a question. I replaced the capacitors on the bias board. Unfortunately, I touched one with a soldering iron. Should it be ok, or is it damaged and need to be replaced?

Don’t worry 😉

5 hours ago, xinvisiblex said:

Hello. I have a question. I replaced the capacitors on the bias board. Unfortunately, I touched one with a soldering iron. Should it be ok, or is it damaged and need to be replaced?

It should be OK. Power it up without the output tubes in and make sure the grid of that output tube has negative voltage on the grid to ensure the cap isn't shorted.

On 26/12/2025 at 9:15 PM, SkunkieDesigns said:

It should be OK. Power it up without the output tubes in and make sure the grid of that output tube has negative voltage on the grid to ensure the cap isn't shorted.

Would removing the output tubes, turning on the amplifier, and checking that the bias meter readings aren't out of range be sufficient? Should I also check whether each output tube socket responds to adjustments? Wouldn't such a one- or two-minute test, if the bias meter reading is damaged, also damage the transformer?

On 28/12/2025 at 5:20 AM, xinvisiblex said:

Would removing the output tubes, turning on the amplifier, and checking that the bias meter readings aren't out of range be sufficient? Should I also check whether each output tube socket responds to adjustments? Wouldn't such a one- or two-minute test, if the bias meter reading is damaged, also damage the transformer?

The bias meter won't respond without the output tubes in place. When I was suggesting is to check the voltage the on the output tubes grid pin, with the tubes removed. This can be done from the top of the amp, with it powered on to limit your exposure to high voltage. If they cap was damaged/shorted, that one tube grid voltage would be high positive voltage rather than the normal negative voltage. You don't want to power the amp on with the tubes installed with positive voltage on the gird, it would almost instantly destroy the tube. With no output tubes installed, it won't damage anything.

18 minutes ago, SkunkieDesigns said:

The bias meter won't respond without the output tubes in place. When I was suggesting is to check the voltage the on the output tubes grid pin, with the tubes removed. This can be done from the top of the amp, with it powered on to limit your exposure to high voltage. If they cap was damaged/shorted, that one tube grid voltage would be high positive voltage rather than the normal negative voltage. You don't want to power the amp on with the tubes installed with positive voltage on the gird, it would almost instantly destroy the tube. With no output tubes installed, it won't damage anything.

Thank you very much for your reply. I took a photo to be sure. Will grounding the amplifier's chassis be sufficient?

I have just taken delivery of a Geshelli Labs Archel 3 Pro to use as a headphone amp but thought I’d try it as a pre amp to the R8. It also meant I could utilise the DACS XLR outs which is supposed to be of sonic benefit on the Denafrips Ares 15th DAC.

Thus far however I still prefer using the R8 without the Geshelli . Admittedly the Sonic Link ‘Voices’ XLR cable is not as good quality as my Audio Sensibility Testament RCA so perhaps this is a factor ?

How has anyone else found pairing the R8 with a pre amp ? Any winning combinations that brought about much difference ?

✍🏻 EDIT * I have this week replaced the XLR cable with a second hand Chord Anthem 2 cable . WOW !!!!

Absolutely transformative . The little Geshelli combined with the R8 is absolutely blowing me away . Detail and imaging like I have never heard . Phenomenal 🤯🤗

Edited January 12Jan 12 by Treerover
Changed the set up slightly

Happy New Year to all Willsenton owners. Just checking in to say that my totally unmodified R8 is now 5 years old, still working perfectly with my vintage tube set and still making great music. Still one of the best buys I ever made. Happy listening!