Willsenton R8 Owners & Discussion Thread

[Atmaj]

10 minutes ago, demoiree said:

@Atmaj did you buy the Sylvania off ebay? vivatubes seems to have some. 

I bought from https://www.thevalvestore.com.au/. Neil had few NOS for 6SL7 and luckily I found a pair of this. Checked on his Maximatcher and they matched.

[demoiree]

1 minute ago, Atmaj said:

I bought from https://www.thevalvestore.com.au/. Neil had few NOS for 6SL7 and luckily I found a pair of this. Checked on his Maximatcher and they matched.

Will check with him what else he has 

[Atmaj]

1 minute ago, demoiree said:

Will check with him what else he has 

Yeah, check with him Neil is a nice guy. I think he still has Brimmer.

Edited October 8, 2020 by Atmaj

[2Dculture]

6 hours ago, demoiree said:

@echorec

regarding the white noise /hiss , i suspect it is due to the stock 6SL7 , will report back if the noise still evident once i roll in some quality 6SL7(which i still not sure what to get yet!)

Yes, I believe you're right. On stock 6SL7, I hear a buzz/hiss when I put my ear near the mid woofer. When I rolled to a shuguang 6SL7, the sound went from a buzz/hiss to a hum. 

 

I barely hear the sound when I listen nearfield. Moving back a couple of feet, I can't hear either noises 

[echorec]

The Tung Sol 6SU7GTY's arrived yesterday. Very neat looking tubes. These are the NOS brown micanol base, black glass military variants with matched triode elements. According to the seller, their burn-in is ~48 hours, so I have some time to go to make judgement. But 5 hours in I can already hear a subtle change in presentation.

 

I'm curious - The manual specifically warns against leaving the R8 idling for long periods of time. Why is this?

[Atmaj]

@echorec

I have also finally ordered TS 6SU7WGT/GTY but it is not black glass one. Not sure what the difference is, too confusing when buying these. Let us know your thoughts on these tubes. By the way, which 6SN7 are those?

 

Previously I forgot to mention with my update on tube rolling that I actually fell in love with the mids of TL EL34s but lack of highs forced me to go towards 6CA7EH.

 

Regarding the idling stuff, I haven't checked the manual but whatever is in the manual is kind of common care of tube amplifiers in general. I don't see any issue with leaving amp idle for long time but will check again in manual. I believe that is to do with Transformer saturations. However, why someone would like to leave it idle for long period of time? You can certainly leave it idle for an hour or two but not for days.

 

I have also done some performance testing on this amp over the weekend. I will post it later with some photos whenever I get a chace.

 

 

Edited October 14, 2020 by Atmaj

[echorec]

@Atmaj

 

When you say TL EL34s, do you mean the Tung Sols EL34Bs or something else? I have too many tube names and numbers swirling in my head

 

The 6SN7s I'm using are NOS RCA 6SN7GTBs.

 

Yeah the idle part I was curious about because I often see people that burn in their tubes by leaving their amps on overnight. I wouldn't feel comfortable doing that with this amp.

 

Looking forward to your tests! Appreciate you sharing!

[Atmaj]

50 minutes ago, echorec said:

@Atmaj

 

When you say TL EL34s, do you mean the Tung Sols EL34Bs or something else? I have too many tube names and numbers swirling in my head

 

The 6SN7s I'm using are NOS RCA 6SN7GTBs.

 

Yeah the idle part I was curious about because I often see people that burn in their tubes by leaving their amps on overnight. I wouldn't feel comfortable doing that with this amp.

 

Looking forward to your tests! Appreciate you sharing!

Yes, I meant Tung Sol (what a stupid I am )

[08Boss302]

Really happy to find this thread.

Mine was ordered in mid August, Well it was a fathers day gift actually, which was totally awesome.  My year has been a bit up/down and my wife and daughter knew I was interested in this amp and made it happen.

I had to wait for production and it finally shipped early september...I took the boat option for postage, I am in no rush to get it and the money saved will go toward tubes.  I bought some tubes for my Vincent Neil and will  speak to him again when I got to buy for the R8. 

Yong has been great to deal with on this purchase.  Has always answered my questions and got back to me on any query.  I asked him what tubes would be compatable in the power stage and he supplied me with this information... It might be handy for you all also

 

(I've cut out my personal details at the top of the email but the body reads as follows)

Set at KT88 when use KT88, 6550, kt90, kt100

Set at EL34 when use EL34, KT77, 6CA7

Regards,

Yong Lee

 

The amp arrived in Melbourne last week, just waiting for it to go to freight forwarded and all thigns going to schedule I should see it next week some time. 

I chose Black with KT88....

 

Some top information in this thread thus far.  Will happily post some pics once its set up and running. Hopefully I dont have any channel imbalance, its actually the first time I have heard of any issues but Yong also told me there is a warranty point in Melbourne and Sydney so I am happy that should anything untoward present there is local coverage.

https://www.china-hifi-audio.com/en/pages-title-page-19

 

Cheers.

[Atmaj]

Hi guys,

 

Here are the outcomes of my very basic performance testing of R8. Could not do in detail as I don't have all the equipments but major two tests were done and the outcome is great.

 

Below are 2 images of my mini oscilloscope. The square waveform test indicates how good amp amplifies input signals in it's purest form. Ignore the noise in the wave form as my Oscilloscope is not professional and I do not have a function generator so I used online waveform generator for these tests. The main objective is to check if square waveform looks similar to input waveform. The below image is at about 10Vmax  after which it starts little bit distorting in vertical lines which is really great. I have also compared waveforms with input so that noise is not from amp.

 

 

 

 

Second image is for sinewave amplification. It is produced with purity. I have checked for 30Hz, 1KHz, and 15KHz, all were same and no noise or deformation added in. This image is just before it starts distorting.

The clipping starts at 32.65V peak to peak for 6CA7EH tube in Triode mode on 8 Ohm load. This indicates that the power output of the amplifier for this tube in Triode mode is about 33.3Watt which is as per advertised. The power output for same tube for UL mode is much higher and beyond the capacity of my Oscilloscope hence could not test it but who cares when the lowest stated output is like that then it will be perfect for UL mode and KT88 tubes too.

 

 

I also did frequency response test and is pretty flat from 20Hz to 20KHz (performed manually by changing input frequency and monitoring on oscilloscope. Do not have graphical image in absence of equipments).

 

In summary, very happy with this amp and a wise decision to purchase this over branded one at multifold cost. 

 

 

 

Edited October 15, 2020 by Atmaj

[muon*]

.................

Edited July 22, 2021 by muon*

[Atmaj]

4 minutes ago, muon* said:

@Atmaj no pics shown.

Sorry, copy paste did not work. Corrected now.

[echorec]

@Atmaj

 

Thanks for sharing! The frequency response is what I was really keen on seeing because my initial impressions of the R8, when I first received it, were that it had a bumped up top end and upper mids. Tube changes and break-in smoothed that all out for me, thankfully. It's nice to know the freq response measure relatively flat in your test!

[Atmaj]

1 hour ago, echorec said:

@Atmaj

 

Thanks for sharing! The frequency response is what I was really keen on seeing because my initial impressions of the R8, when I first received it, were that it had a bumped up top end and upper mids. Tube changes and break-in smoothed that all out for me, thankfully. It's nice to know the freq response measure relatively flat in your test!

You are correct, tubes will mainly affect that. For me, Sylvania 6SL7GT, Tung Sol 6SN7GTB (new stock) and Electro Harmonics  6CA7EH gave a pretty flat response. With stock tubes, the response in high frequency is much higher.

 

For tube amp, they are mainly weak in low frequencies if the quality of the transformer is not good enough but I did not find that in this amp.

Edited October 16, 2020 by Atmaj

[echorec]

I feel good to comment on the Tung Sol 6SU7GTYs. I'm past 48 hours run time and have been doing some serious critical listening the past few days. Are they any good? Do they sound better than my GE 6SL7GTs? The answer to both is, yes. The differences are fairly subtle, however, so it in no way detracts from the value to be had with the GEs (~$50 USD matched NOS pair vs $200 USD for the Tung Sols). By comparison, the Tung Sols offer a little more delineation to elements within the soundstage. Sound and instruments just snap into focus a little better, and, hence, have a little more space between them. When I load the GEs back in, there's just a tad bit smearing by comparison. But - Had I not bought the Tung Sols, I would be completely happy with the GEs, so don't steer away from them if you are on a budget. Keep in mind I'm pairing everything with new production Tung Sol EL34Bs. I'm not yet ready to load up the KT88s again, but when I do, I'll compare the GEs and Tung Sols again. By then I might have also added those Sylvanias @Atmaj likes too. Fun stuff!

[Atmaj]

18 minutes ago, echorec said:

I feel good to comment on the Tung Sol 6SU7GTYs. I'm past 48 hours run time and have been doing some serious critical listening the past few days. Are they any good? Do they sound better than my GE 6SL7GTs? The answer to both is, yes. The differences are fairly subtle, however, so it in no way detracts from the value to be had with the GEs (~$50 USD matched NOS pair vs $200 USD for the Tung Sols). By comparison, the Tung Sols offer a little more delineation to elements within the soundstage. Sound and instruments just snap into focus a little better, and, hence, have a little more space between them. When I load the GEs back in, there's just a tad bit smearing by comparison. But - Had I not bought the Tung Sols, I would be completely happy with the GEs, so don't steer away from them if you are on a budget. Keep in mind I'm pairing everything with new production Tung Sol EL34Bs. I'm not yet ready to load up the KT88s again, but when I do, I'll compare the GEs and Tung Sols again. By then I might have also added those Sylvanias @Atmaj likes too. Fun stuff!

Thanks for sharing your experience. Yes, the differences will be subtle between those NOS tubes but if you keep the cost aside, it matters for us isn't it? . I am also not expecting huge difference between Sylvania 6SL7GT and  Tung Sol 6SU7 GTY but if there is any, it will give me that pleasure.

 

I bet you will put back TS EL34 immediately after loading KT88 if you love mids. I did that with EH6CA7 and couldn't stand for it even though 6CA7 do not have as good mids as TS EL34 but it is still EL34 family tube.

 

What I love about tube amps is that we can do all these experiments against sticking to what you have with SS amps. I am keen to upgrade coupling and grid bypass capacitors but they already are of good quality and not sure if PIO capacitors will make any difference. Will still keep on thinking about it for now 

[echorec]

20 minutes ago, Atmaj said:

What I love about tube amps is that we can do all these experiments against sticking to what you have with SS amps.

I agree! There's a lot of enjoyment going on for me, from sourcing the tubes to refining the sound of the amp. I do wonder what high-end caps could do to the R8. Positive results have been reported with similar circuits. Maybe next year...

[demoiree]

Hi guys , been awhile since i posted here . I thought some of you might be interested with my impressions between the X7  and R8(stock form) , here was what I posted in the x7 thread.

 

X7

Pros

- overall Better build, volume knob etc feels good at touch, has that Luxman feel to it.

- stock tube have lower noise floor  than R8, signal tubes are Slovakia JJs

- love the dual Vu meters , easier to bias with one hand as you can turn a switch to a valve to view its current on each vu meter.

- remote control feels more luxury,  single piece of aluminium , also buttons are quieter.

- one 12ax7 voltage amplifier tube , cheaper to roll 

- has tube rectifier

- has phono-input

- switching to pre-amp mode , no background hissing

 

Cons

- when running stock preamp tubes , i feel it is lacking a layer of "air" on the top , but when i swapped in some NOS RCA 5963 , it makes it more holographic .

- lacking that lush mid-range boost that el34 offers , but manufacturer says X7 can take EL34 with correct bias adjustment , so will try that out later down the track.

- remote control can only change volume and mute(cannot change TR/UL or input selection) .

 

Stock tube(KT88 & stock JJ preamp tubes) sound signature

- UL mode : powerful, great bass control , clear highs , less "air" when compared to R8 

- TL mode : mids becomes touch better and highs are more rolled off, very relaxing to the ears , great for vocals in this mode.

 

R8

Pros

- ability to switch between EL34 and KT88 tubes 

- remote control able to switch TR/UL , also input selection

- better mid range , possibly due to EL34

- comes in all black

- many good options on good NOS 6SL7 & 6SN7 , with good tubes I believe the R8 can sound very good.

 

Cons

 - no memory of TR/UL selection , always default to Triode on start up

 - higher noise floor than x7(stock tubes)

- stock tubes aren't that great, sound stage slightly bias to one side( stock tube not matching)

- more preamp tubes , more expensive to roll , i.e two good 6SL7 are expensive

- biasing requires two hands , i.e hold on to a toggle switch to view the bias , and another hand to turn the pot.

- no moving VU meters when music playing

- remotes not as good quality , buttons are noisy.

 

Stock tube(EL34 & stock chinese premap tubes ) sound signature

- UL mode:  good bass , I'm actually quite surprised that it doesn't sound too much different than the x7 when playing at moderate volume . but can start to hear it struggles when playing louder .  sound stage is more spacious and has more air than x7.

- TL mode : great mids and still can hear good transparency and nuances , overall I can say vocal sounds more pleasing than the X7 in  TL mode.

 

 

 

having said, all are my own humble opinions and i feel there are too many factors that can affect the sound , its really hard to compare when it is not apple to apple! Each has their own strength and I can imagine myself keeping both for sometime to come.. as they are not completely the same and has so much room to improve when you throw in some good tubes.

[echorec]

Well a terrible thing just happened - again. I powered up my R8, walked away and heard a terrible sound coming from my speakers. V1 power tube was glowing red - again. So this problem now came back, but now it does it every time I turn the R8 on.  So I cannot use the R8 at all. Any ideas on what is going on? Bias is pinned to the right when this happens, so full voltage is happening in V1. Bias capacitor? Ugh, this is terrible. Also to clarify, it is not the tube itself. Any tube will glow red in V1 now. I guess it is time to take it in for repair...

[Xlrg]

Sorry to hear that. Hopefully you can get it fixed and update us on what exactly was going on...

[Atmaj]

10 minutes ago, echorec said:

Well a terrible thing just happened - again. I powered up my R8, walked away and heard a terrible sound coming from my speakers. V1 power tube was glowing red - again. So this problem now came back, but now it does it every time I turn the R8 on.  So I cannot use the R8 at all. Any ideas on what is going on? Bias is pinned to the right when this happens, so full voltage is happening in V1. Bias capacitor? Ugh, this is terrible. Also to clarify, it is not the tube itself. Any tube will glow red in V1 now. I guess it is time to take it in for repair...

Sorry to hear that. Bias is pinned to the right when this happens means full  current is flowing through the plate. I would reckon to take it for a full check. Something is causing high current to flow through the tube.

[echorec]

Yeah, it is so strange that this happened before, then went away, and now came back. I wonder why that could be. Man, I am totally crushed right now. I just bought a bunch of new records. Well, back to solid state for the next week or so. I will report back later when I find out what the issue is. I also contacted Mr. Lee, however, I am in the USA and mailing something back to China is just not feasible, and I have a good hifi shop locally that can take it in.

[Atmaj]

19 minutes ago, echorec said:

Yeah, it is so strange that this happened before, then went away, and now came back. I wonder why that could be. Man, I am totally crushed right now. I just bought a bunch of new records. Well, back to solid state for the next week or so. I will report back later when I find out what the issue is. I also contacted Mr. Lee, however, I am in the USA and mailing something back to China is just not feasible, and I have a good hifi shop locally that can take it in.

Ask Mr. Lee for the warranty repair near you. That will save you money.

 

Also I have a schematic drawn from the actual component, let me know if you need it.

[echorec]

10 minutes ago, Atmaj said:

Ask Mr. Lee for the warranty repair near you. That will save you money.

 

Also I have a schematic drawn from the actual component, let me know if you need it.

Thanks for the advice! I'll let you know what Mr. Lee advises. If it I end up taking to my local HiFi, then a schematic would be a big help. They had not even heard of Willsenton.

[demoiree]

 

59 minutes ago, echorec said:

Well a terrible thing just happened - again. I powered up my R8, walked away and heard a terrible sound coming from my speakers. V1 power tube was glowing red - again. So this problem now came back, but now it does it every time I turn the R8 on.  So I cannot use the R8 at all. Any ideas on what is going on? Bias is pinned to the right when this happens, so full voltage is happening in V1. Bias capacitor? Ugh, this is terrible. Also to clarify, it is not the tube itself. Any tube will glow red in V1 now. I guess it is time to take it in for repair...

sorry to hear that ! are you using KT88 or EL34? 

 

maybe try KT88 if you have some?