So glad you like it - and who said that a better tube in the power supply would/could make a difference? Not me, but a lot of people think this way, unfortunately. As for the St Petersburg Svetlana 5U3C - I do believe that this was one of my best finds for the R800i - and they don't cost very much either - there were a lot of these tubes made, so this is keeping the cost quite reasonable. As for a solid state rectifier stage, I believe that I will leave the R800i well enough alone.
Also, piano is one of the most difficult instruments to reproduce, but the Telefunken is one of but a handful of tubes which can make a piano actually sound like a piano. Of course, a piano is also difficult to record too, but try Beat by Tingvall Trio and Mystische Kalte by Dario Lessing, or even Temptation by Diana Krall.
Solid state rectification may measure better but, all things being equal (and they rarely are), tube rectification sounds better in my very personal opinion. Of course there are great sounding amps with SS rectification, I happen to be listening to one now. So Rachael if you want to go that route for us I would personally be fascinated to hear your thoughts on the outcome!
I bought a Willsenton R8 and I like the sound with my JBL L82. Still wondering if the R800i 805 is an upgrade. The JBL L82 are 88db. Is this sufficient for a Class Amplifier like R800i. Thanks in advance.
Hi jonwoody, While I would love to try full-wave diode rectification, for the time being, at least, I've decided to be satisfied with the amp just as it is. It sounds fantastic anyway, especially of an evening (compared to during the day), and I believe that the best place I could spend money would most likely be in the area of power conditioning.
Hi DaveB1, Definitely the black plate. In fact, I am not aware of a grey plate version being made in St. Petersburg. Meaning that, as far as I know, New Sensor (Reflecktor factory in Saratov) uses the grey plate - which is not the one you want. All St. Petersburg 5U3C tubes also use the famous "winged C" logo as well.
Hi Arjan, Both amps put out similar power, providing the R8 is in UltraLinear mode, although I believe that Triode mode (25 Watts RMS per channel vs 45 Watts RMS per channel in Ultra Linear mode) actually sounds better. You also need to remember that the R8 is a push/pull design, while the R800i is a SET class A design. This means that the sound-signature is slightly different with neither being necessarily better than the other, as it's really personal preference. For me, I love the sound of both amps. The R8 can sound a little more dynamic (especially using KT88 or 6550 tubes) than the R800i, but again, this also can be personal preference. I suppose I could describe the R800i as smoother sounding, but with slightly better clarity. For me, the R800i is an upgrade, but just be aware that to get the best out of it requires more expensive tubes compared to the R8. You could also refer to the Skunkie YouTube channel where she takes you through an upgrade path for the R8, so if you are handy with a soldering iron, this will be the cheaper option. The cost of the upgrades seems quite reasonable as well - I think about $US200.00 in order to carry out all the upgrades that she suggests. CONCLUSION: The R800i is the better sounding amp IMHO, BUT the R8 (especially with the right tubes) is no slouch in the sound department either. What's more, especially if money is tight, you could carry out the Skunkie upgrade to improve its sound quality even further. DISCLAIMER: I have not heard an R8 with the upgrades.
Thank You RaechelW for your feedback. Highly appreciated. I will give it some thoughts. The R8 is my first tube amp and I want to dig deeper. Unfortunately not that handy with solder;
Thanks, Rachael! I'm not sure I agree that the Harbeths are warm. They seem neutral to me. And very, very transparent. But let's not disagree about that. I happen to have a pair of current TungSol 6SN7GTBs. So I'll try them. And I take your point about the Telefunkens. I'll give them some time. They certainly sound unspectacular at the moment. And subtle micro detail in complex orchestral pieces is exactly my cup of tea. I'll report back in 100 hours or so...
Yes, the black plate is the best sounding version. Rachael, the grey plate versions that I have also have the winged C logo, with dates ranging from 1960 to the late 1960’s. They are outstanding rectifiers, pretty much better than any other rectifier I have tried. The black plates sound a little better, but the grey plates are very, very good.
Rachael, your comments about "honest sound" seem so befitting to me. I also hear a little less warmth--yet no particular area of harshness in trade for more neutrality on the warmth scale. I don't mind it at all, and I say this as a "warmth" loving listener. I must admit that a properly implemented tube amp coupled with horn speakers (what I'm using) is intoxicating at times. But, with a partially horn loaded speaker like mine (isn't the Cornwall IV "partially horn loaded"?) things can get bright quickly. These Tung Sol reissues might get a shade brighter than central-neutral, which is not a bad thing. I think being on this side of the spectrum in tube world is interesting. And, in my system, the thing that sounds great with this TS's in place is there is some big, big soundstage. The soundstage in my room is quite large and holographic.
Hi tubesandvinyl, Your reply has added to my knowledge, so thank you for that. I have 4 (or 5) of the St. Petersburg tubes ranging from the 50s into the 60s, and they are all black plates. This is why I (wrongly) believed that the grey plates came along much later. As for the winged "C" logo, Svetlana used the stylised "S" and the winged "C". Typically, the winged "C" was used on their earlier tubes, but when New Sensor acquired Svetlana, I believe they also acquired the logos as well, but I believe all their tubes use the stylised "S" - although I could be proven wrong on this point. Either way, I don't believe that the New Sensor version ever had black plates, in which case, it would be the colour of the plates that would specifically dictate as to whether the tube is an original St. Petersburg, or the inferior New Sensor tube. There are other differences too, between the Saratov tube and the St. Petersburg tube, with some differences being quite subtle. Either way, it would appear that the tube everyone should be looking for is the Svetlana with the winged "C" logo, the "5U3C" printed within the logo, and the plates being black in colour. I have some notes somewhere which go into much more detail about the differences, but I have so many tubes and so many scattered notes lying around in boxes. In other words, all I know for sure, is that the tubes that I have are St. Petersburg manufactured with black plates. I'll see if I can dig out the detailed notes on the history of this tube, although that may be more easily said than done.
Hi Prisoner, Regarding the new production Tung Sol 6SN7GTB, the word "honest" was the only word I could come up with at the time to describe its sound. It certainly isn't objectionable in any way, so, yes, a very honest sounding tube. One thing I have never mentioned is that when I first purchased the R800i, the first change I made was swapping the JJ ECC83S for the JJ ECC803S and the Russian NEVZ 6H8C with the current production Tung Sol 6SN7GTB. Just these changes improved the sound substantially. As for your Cornwalls, I believe that all Klipsch speakers larger than the Cornwalls ARE "fully" horn-loaded. The difference being the bass driver is not horn loaded while the midrange and tweeter drivers are. But then, I'm sure you already know this! Talking about soundstage, holographic, plenty of "air", as well as the plethora of other sound descriptors, what I specifically look for in the final sound of a tube amplifier as a whole, is the tubey warmth (but not too much as this can effect ultimate detail); but the other three things which I crave equally is midrange (I usually use well recorded piano and the human voice for this "test"). Brass instruments must also present themselves with plenty of bite too - this is where too much warmth can soften the level of bite, which is part of the reason why too much warmth can be too much of a good thing - also dependent on the type of music you listen to as well. Soundstage and that magical holographicness, if this is even a word, is also very important to me. I suppose I should mention these descriptors more often, but then the sound of the room and the speakers also play a very important part in all this too - at least in the form of which tubes are ultimately most suited to one's setup. Specifically, my room is treated and passes the "clap test", so reverberation is well controlled. Bass traps as well, while my speakers are the very neutral sounding Q Acoustic Concept 500s - refer here for a review on these:
I used to have a pair of JBL L82 and they are fantastic speakers. They work very well w/ the R800i. Just very "well rounded" sounding w/ a valve amp like the R800i !!
The gray plated 5U4G Svetlana's I've been using have a small S on the tube, but certainly not the Flying C winged Svetlanas that Rachel has described. I'm guessing they're the New Sensor version of the originals. They certainly sound better than the original 274b from Wellsenton, but hopefully not as good as the black plate Svetlanas. I was able to pick up a couple of the Black plated Flying Cs from a seller in Ukraine with 100% reviews., Unfortunately it'll take another two weeks to arrive. In the meantime, I've swapped out the mains cable to the Shunyata power conditioner and speaker cables. Ain't this fun?
Rachel, OMG! I love your speakers. For some time I've wanted to keep my CW IVs and use the Concept 500s with my Marantz PM KI Ruby. Ken Ishiwata (now deceased) voiced the amp with Your Concept 500s. You do a wonderful job explaining your experiences. Thank you!
800i owners, I just tried out some vintage 805s. There was an issue with them so I had to send them back to the seller. BUT, when I put my stock 805s back in, I experienced an issue with the bias pot on the right channel. It would only bias to 20ma and then with a slight turn it went right up to 110ma! I think the pot is a little sticky or something. This is important because I've only had the amp since 12/21/2023 and I'm concerned that what Skunkie Designs found in the Willsenton R8 is likely going to be found inside our 800s. I really need to open up the unit, take photos/videos and compare it with the R8. I bet our 800s need that resistor to prevent full throttle bias occurring in the event the wiper in the bias pot gets stuck.
Hi DanaMac, Yes, the tube that you have would be a New Sensor tube. Still, if it's well balanced with a high mu/Gm (gain), it would sound better than the stock 274B, so you are not imagining an improvement! The Winged "C" black-plate is simply better again. Happy listening when the St. Petersburg tube is finally delivered.
Hi RachaelW, Looking through the specs on the Concept 500 I see that it operates at 6 ohms like my Living Voice IBX-RW4. I've tried both the 4 and 8 ohm binding posts on the R800i and can't quite decide which is more musical. I'm thinking the 4 ohm post gives more of a thin presentation in the midrange versus the 8 ohm post. I see in one of Thomas's YouTube videos where he's demoing the Concept 500, he prefers the 8 ohm tap on his Mac integrated versus the 4 ohm tap. Which are you using?
Hi Prisoner, Sometimes I wonder if I explain myself thoroughly enough, but thank you for that. Of course, when I list tubes that I use, I simply accept that other audiophiles reading my humble ramblings would also take into account that the room and the speakers also play a part in the resultant sound. As an example, while I love the TeleFunken 12AX7/ECC83 smooth-plate coupled with the Sylvania 6SN7GTA straight-plate, some peeps might find, due to the different environment and speakers (and other tubes) they are using, that the resultant sound using these tubes, may be a bit too warm, or not warm enough. Having said this, the Telefunkens are reasonably neutral but with a very nice "tone", (so these tubes should suit most people), while the Sylvania GTAs adds just the right amount of warmth that I personally like, while not detracting (or altering in a negative way) from the everything I like about the Telefunken. The thing is that while most people understand the synergy between different pieces of hi-fi equipment is a real thing, I don't think everyone realises that the synergy must also be right between the various tubes that are being used. As a further example, if one doesn't like the Sylvania GTAs because they are perhaps too warm, then the NOS circa 70s Tung Sol 6SN7GTB may suit - IF money is tight, you could fall back on the current production Tung Sol 6SN7GTB - this is because the NOS TS and the current production TS have one thing in common - detailed presentation with not much warmth. As for Ken Ishiwata, he was an amazing guy and was a true "Golden Ear". He also loved the Concept 500s, and his ears were used in the voicing of quite a few (some now quite famous) hi-fi pieces. It was a big loss to the industry when he passed away. NOTE: I would not give away my Concept 500s for love nor money - I love the voicing of these speakers because absolutely no frequency range is emphasised - they are just so neutral sounding. Ok, they do have one flaw - I wish their bass went down just a little further, even though the bass itself is beautifully nuanced, but then for most music, you CAN use the 500s as full-range speakers, i.e., no subwoofer necessary.
Hi DanaMac, In regard to the R8/500s I use the 8 ohm tap, but I use the 4 ohm tap on the R800i. Of course, because you have different speakers and impedance is frequency dependent, it's really something you need to decide for yourself as to which tap sounds better. It's usually quite a subtle difference, and sometimes it's difficult to tell which tap is better, but what I did was simply listened to a few tracks from my main playlist on Qobuz (I also am a member of Tidal, but find that Qobuz, in general, sounds just that little bit better), and from what I was hearing, decided that the 4 ohm tap was best for the R800i, with the 8 ohm tap being better with the R8. As you may know, I also own the Cayin Soul 170i, and find that, again, the 4 ohm tap is the best for my speakers. But it WILL vary depending on the amp/speaker combination, meaning that just because the 8 ohm tap sounds best for me with the R8, does not mean you should use the 8 ohm tap with all amplifiers while using a specific speaker. So, in summary, even though your speakers and mine have a nominal impedance of 6 ohms, doesn't mean that you should be using the same tap as I do. If you believe the 8 ohm tap sounds better while using the R800i, then continue using it. I'll throw something else into the mix just to confuse you further - although NOT on purpose; I promise you. IF you change the speaker cables, this can change which tap sounds better! So, just something else you need to know. Isn't being an audiophile just so much fun? Usually it is, but not always - it can also be very frustrating. EDIT: I also watched Thomas' videos and he had a really hard time getting the 500s sounding their best, but then Thomas likes his sound to be warm, but also a little hot on top. Of course, the 500s are very neutral sounding, so he ended up throwing quite a bit of money at the 500s in amplification before he was satisfied/convinced that the 500s are indeed a very special speaker - especially for the money.
Hi Prisoner, I'm wondering if a bit of dust or other contaminate has got into the pot. Try this: Make sure the amp is switched off, and turn the pot from fully anti-clockwise and then full clockwise. Do this about 10 times. Then turn your amp on with the bias set to low, and then re-bias the amp. Hopefully this will fix the problem. Finally, place a piece of tape over the bias hole (the hum hole as well), so that no more dust can enter the pot. Unfortunately, I have not seen a circuit diagram for the R800i, so it's difficult so say whether it suffers from the same problem as the R8, i.e., possible problem in the design, causing a power tube to go nuclear (red plating), or worse still, blowing an output transformer - I also worry that such a thing happening could damage a speaker as well. Hopefully not.
