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Willsenton R8 Tube Integrated Amplifier. Amazing Sound, Amazing Value.

32785 Views 75 Replies 15 Participants Last post by  Jon S
This thread is a general discussion about the Willsenton R8 tube integrated amplifier. I am just kicking off the thread for now, but will add some general info about this amp later. The amp has opened my eyes (ears?) to the possibilities of relatively low-cost tube amps imported from China. To start the ball rolling, this YT video is what inspired me to buy this amp - a decision I am thankful for every day


Similarly, this one from Steve Huff . . .

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I bought my R8 here:

Mine cost me about 100 bucks less than the current price, which has increased due to various factors, including rising demand. I had to pay close to 300 bucks for shipping and a modest amount if import duties (into the UK) but the total cost still came to just about $1,000 USD. It is the cheapest amp I have bought for years!

For anyone contemplating buying, my experience with China Hi-Fi was good and I would have no worries buying from them again. I would recommend getting the option with the cheapest (EL34) tubes, as it is all but guaranteed that you will swap out the stock tubes for something better. I was impressed by the beautifully smooth and euphonic sound right out of the box, but the stock tubes are cheap and not all that good IMO. I soon replaced them with relatively inexpensive Tung Sol current production tubes and these have served me well so far, although two of my tubes are now NOS (new old stock) Tung Sols which are 75 years old!

Here is a photo of my amp as it stands currently:


Since that photo I have replaced two further tubes:


I should stress that I am very much a newbie when it comes to tubes but I am, so far, delighted with my choices.

The full complement now of tubes in my amp is:

4 x Current production Tung Sol EL34Bs for power tubes
2 x NOS (1945) Tung Sol 6C8G (with adapters) in the position originally occupied by 6SL7 tubes
1 x Current production Tung Sol 6SN7
2 x Current production ShuGuang CV181-Z 'Black Treasure' tubes in the position originally occupied by 6SN7 tubes

The rational for these tubes is as follows. I find that the EL34s are much more 'musical' and suit my musical tastes and audio preferences much better than the KT88 power tubes that the amp came with. My tastes are female jazz vocal, small jazz combos, acoustic music in general, which makes up 80% of my listening, with the other 20% occupied by a wider mix of genres. To my ears, the EL34s sound like 'music' where the KT88s sounded more like 'hifi'.

The Tung Sol 6C8Gs are the preamp tubes and these seem to me to make the most difference to the sound quality. This figures as whatever these tubes do sonically, being the first in the chain, will be amplified by the rest of the amp stages. I also have a pair of NOS Russian MELZ 6SN7s which also sound glorious, but to my ears the Tung Sol 6C8Gs beat them on most metrics.

The single 6SN7 in the centre position is the rectifier tube and is not in the audio path, so for me this means I can pay less attention to it. Others may have a different view, but I consider it to be the last tube to impact on SQ.

The pair of 'fat' tubes in the 6SN7 positions are ShuGuang current production 'Black Treasures' which are very highly reviewed and I just had to try them. I was considering more NOS tubes in those positions but the whole NOS area is a minefield for me and, until I have more knowledge, I am sticking more with current tubes. I am delighted with the ShuGuangs and will give a more in-depth review of them later.


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• Pure hand-made, Point to point manual welding.
• Use a square power transformer specially developed for this machine.
• The output transformer uses two high quality wideband EI output transformers.
• The preamp stage uses one 6SN7 for power supply filtering.
• The voltage amplification stage and the push stage use two pairs of 6SL7 and 6SN7 tubes, respectively.
• The power amp stage uses four KT88/6550/EL34 tubes for class AB single-ended power amplification.
• Triode and ultra-linear selection are available. The triode works in a soft, pure-and sleek sound, suitable for listening to vocals, strings and other types of music. Ultra-linear working mode, sound-tone open, unrestrained, good momentum, suitable for enjoying big scenes, big dynamics and other types of music.
• External independent BIAS-ADJ current display header. Adjustment and BIAS meter monitoring function keeps the best state of the power tube at all times.
• External EL34/KT88 tube selection function, easy to replace different types of tubes, adding endless fun.
• Infrared full-featured remote control.
• Use thick silver plated signal leads.
• With pure post-level function, it can be connected to independent preamplifier signal input.
• Power on mute delay function, soft-start feature to prolong tube life (about 30 seconds).
• Select Japanese ALPS high-end motor potentiometer.
• Easy-to-install plug-in tube cage cover.

Product parameters:
Frequency effect: 10Hz 40kHz (+/-0.5db)
Total harmonic distortion: 1% (1kHz)
Signal to noise ratio: 91dB
Input sensitivity: 380mv (when Integrated amp input), 820mv (when pure power amp input)
Input impedance: 100KΩ
Output impedance: 4Ω, 8Ω
Rated output power:
25W+25W (RMS triode working state) (KT88, 6550EH or EL34)
45W+45W (RMS ultra-linear working state) (KT88, 6550EH)
40W+40W (RMS ultra-linear working state) (EL34)
Preamp stage power supply filtering Tube: 6SN7*1
Voltage amplifier stage Tube: 6SL7*2
Driver stage Tube: 6SN7*2
Power vacuum tube: KT88*4 or 6550EH*4 or EL34*4 (only 1 kind of power tube come, you need to choose)
Power supply voltage: AC 100V to 240V 60Hz/50Hz, 110V, 115V, 120V, 220V and 230V version are in stock. (there is a 230V/115V voltage change-over switch inside of body), (100V, and 240V version need to take 3-14 business days to order)
Power consumption: 280W
Dimension: (W*H*D): 400*200*390 mm
Net weight: 26kg
Gross Weight: 30kg
Working Condition: Temperature: 0℃~40℃ Moisture: 20%~80%
Storage Condition: Temperature: -20℃~70℃ Moisture: 20%~90%
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Interesting article on the dilemma of choosing NOS tubes, with all the pitfalls and dangers for the unwary or inexperienced (me!) compared with using current production tubes.

I have a mixture of NOS and current, as listed above. I'd love to try some NOS Mullard EL34s but, aside from the expense, there are so many fakes out there that I am super-wary.
I believe the euphonic harmonics of tube amps could be easily designed into a solid state amp, and I think it's been done at least a couple of times in the past, including by Bob Carver.

Should be cheaper and way cooler/energy efficient, but there's no denying the romance of warmly glowing tubes.
I believe the euphonic harmonics of tube amps could be easily designed into a solid state amp, and I think it's been done at least a couple of times in the past, including by Bob Carver.

Should be cheaper and way cooler/energy efficient, but there's no denying the romance of warmly glowing tubes.
Hi Noah. It may well be true that the 'tube sound' could be recreated by solid state equipment. I guess that, one day, the taste of a fine filet mignon may be recreated in a laboratory somewhere. Would we prefer the lab version to the 'real thing'? Would it be truly identical in taste and texture? I don't know. To try to recreate the sound of tubes with transistors seems to me to be somewhat like Dr Johnson's dog.* Why bother when one can have the 'real thing'?

Heck, there are plenty of tube aficionados who would say it isn't even possible to recreate today the sound of a tube from 70 years ago, despite all our technological advances in the meantime.

And at what price would this SS interloper come? Surely a lot more than the Willsenton R8?

It is true that there is some additional rigmarole involved with tube amps, but the tubista sees that as part of the fun, much the way a vinyl enthusiast gets a kick from removing the album from its sleeve, zapping it with his (or her) antistatic gun, placing it on the platter, brushing it clean and, finally, lowering the stylus into the groove.

After decades (too many) and plenty of dollars (too much) spent on SS amps, I have come late to the world of tubes. But I am loving it. The 'realism', the 'thereness' of the musicians in my room. The 'space' between instruments -- instruments which sound amazingly like real, actual (acoustic) instruments in my room, it all brings me a pleasure I have not enjoyed from music for a long time. And certainly not for the price of the amazing R8.

I should add that my musical tastes are female jazz vocals, small jazz combos, acoustic instruments and so on. I believe that if Swedish Death Metal was more to my tastes, I would prefer a big, phat SS amp with hundreds of watts driving some enormous JBLs.

*The Samuel Johnson Sound Bite Page: Women preaching.../Dog walking...
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Interesting article on the dilemma of choosing NOS tubes, with all the pitfalls and dangers for the unwary or inexperienced (me!) compared with using current production tubes.

I have a mixture of NOS and current, as listed above. I'd love to try some NOS Mullard EL34s but, aside from the expense, there are so many fakes out there that I am super-wary.
I am still trying to fully understand what cause the sound of tubes to vary other than the physical construction. Should one expect that a fake one that on inspection looks and measures the same as a genuine article sound differently?
I am a newbie with tubes so kindly enlighten me.
I am still trying to fully understand what cause the sound of tubes to vary other than the physical construction.
Why aren't differences in physical construction enough?
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Is this used in addition to or in lieu of another amp?
I tried inserting a tube pre-amp between my receiver's preamp outputs and amplifier. At first I was not impressed but after a few tweaks (adjusting B+ voltages and biases to find the sweet spots of the tubes), it made the music sound better. I believe that the change are due to added distortions because I know that just plain connecting wires add less distortion.
I am so happy I discovered I can enjoy my sound system better with the added distortions of tubes that I ordered an R8 with Psvane preamp tubes.
You will not be disappointed with the R8. Tube amps have various sonic advantages over solid state -- the almost tangible sense of 'being there', the amazing realism with which instruments and the human voice are reproduced, the 'holographic' imaging and the way in which instruments just leap from a black background, all of these are the things I notice every day. The one weakness with a tube amp is the bass. SS amps have faster, better controlled bass and this suits some types of music better than others.* If most of your enjoyment derives from small acoustic ensembles (jazz or classical) or from music centred around the human voice, then IMO tube amps are unsurpassed. If you are more into electronic and thrash metal and so on, then I'd say SS is usually better.

One of the really great things with tube amps is that you can tailor the sound to suit your tastes and preferences simply by the choice of tube you make. With SS, what you get is what you get and you like it, or you get another amp.

* For my taste and musical preferences, I rather enjoy the slightly looser, more 'organic' bass that my tube amp gives me, but it is horses for courses and YMMV.
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I got the impression from a reviewer awhile back, I no longer remember the specifics, that the centre position tube is being used in the supply filter circuit for the preamp section. I remember it being called by the reviewer as used as ripple-eater or capacitance multiplier. If that's correct then it's true that it's not directly in the audio signal path but could affect the noise floor of the preamp section.
Nice to know that it has more sophisticated mitigation for supply noise not found in others.
I'll see what it is when I get the schematics.
I mistyped when I said before that the R8's centre 6SN7 tube was the rectifier. It is, in fact, the voltage regulator tube. It still isn't in the audio path though. If it has an impact on the sound, it is going to be much less than the other tubes I believe. As for the noise floor, the R8 is one of the quietest amps I have ever owned. It is pretty much totally silent - even with the volume wound up to max and my ear right next to the speaker, there is zero hum and barely no hiss. With the volume not at max but well above any level I listen at, the amp is effectively totally silent. I am constantly amazed at the value this amp represents.
I am comparing figures of the datasheets of 6SL7 and 6C8G.
Although their pins can be adapted to suit, their electrical properties especially their grid voltages, plate resistances and gains are significantly different. My honest but novice opinion is that the C68G is more suitable for signal phase inversion duty for push-pull circuits, not signal amplification.

The change to 6C8G, although appearing more robust, may significantly affect R8's linearity and headroom.
It might still play well to around 5-8watts or so if the headroom is reduced.

It all depends on where the operating point of 6C8G will be when plugged into the R8.

One sure way to find out is to 1) get a schematic diagram that will show the resistances used around those tubes, graphing sheet provided in the datasheet and digital voltmeter then 2) plot where the operating point of 6C8G in R8 will be.

A switch is provided to select the output tubes to switch the amp's circuit for either the KT88 or EL34 tubes' best operating points. However, no switches are provided for the preamp tubes. Different types of preamp tubes operate at different electrical points. I'd be careful choosing replacement preamp tubes for the R8.

Also, I am not sure that halving the gain of the preamp tube would improve the SQ. There are reasons why designers use high-gain tubes in the preamp stages.
So, I would be really careful about choosing preamp tubes for the R8.
I cannot disagree with your conclusions. The Tung Sol 6C8G tubes here do sound very, very good, even though, as you say, their gain is lower. While this causes me to listen at around 11 o'clock on the MV, as opposed to around 9 o'clock when using the Melz 6SL7 tubes, I am not hearing any negatives. However, by way of an update, I have recently swapped back to the glorious Melz 6SL7 vintage, military spec tubes from the 1950s and I am finding that I am enjoying the music more. I am starting to draw a distinction between the electrical specs of equipment, which might indicate a potential superiority, and the actual sound I am hearing in terms of musical enjoyment. I am just enjoying the sound the Melz make more. I can't quite put my finger on why this should be so, but it is and I am taking it on face value.

I do not regret buying the vintage Tung Sol 6C8Gs as I see it as part of the learning curve, and they do sound very good as I say. But for now, the Melz are my tube of choice for the 6SL7 slots.
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Jim, from online tube store Valves N More (aka Tube Lab on YouTube) has done a series of videos on the R8 (which he owns), including a great series on tube rolling for this amp. This video is his basic teardown of the unit. Well worth a look IMO.

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