Stephe, many thanks for your work on analyzing this amp🙏🏻 Out of the box the amps looks like a total mess. Hopefully only little modifications could turn it to a „normal performing“ 300B amp. Looking forward to all your next videos.
Love this, one hot mess lol. Here in Canada these amps are $2,000, not cheap especially for only 8 watts. No sugarcoating that this is money wasted. This sure beats some reviewer saying the amp sounds pretty good for the money. You make these videos interesting for those who don’t get it. 👏
yeah but it shouldn't have this much distortion and the craziness at 10K. My super budget DIY build, designed by a hobbyist in their basement, performs way better! And it only really makes around 5W with all the tubes replaced, which adds several hundred $.
@@SkunkieDesignsElectronics I completely agree , but I also believe it's solid start and that when your done it will something special. , I don't mind making few mods to a amp but building from scratch not really something I'm comfortable with .... Yet ...
From my little understanding it’s not just swapping out components for better quality it’s the overall design that makes an amp sing. It’s not that simple. Are these Chinese amplifiers just trying to copy old designs and failing miserably? I have no idea, I certainly wouldn’t risk smoking my expensive speakers playing around with this stuff. 🫣
I'm scared to put my good 300B tubes in it. On a forum I follow, one of these amps redplated a brand new gold lion 300B tube, which if it didn't kill it, took a large % of it's life. That's a $220 tube. Note I had to put $400 worth of 300B tubes and another $150 of NOS driver tubes in it to even come close to performing decently. And the way this amp slams the B+ into the tubes, they probably aren't gonna last long.
Thank you and yes, I am loving this content. I recently bought this amp and, like others, think it sounds good. Must be the tube harmonics. However, doesn't mean that it can't sound better, maybe way better, and I will probably perform any change or upgrade that SDE recommends.
@@SkunkieDesignsElectronics Well, yes and no. First tube amp in 30 years. My first ever amp was a Dynaco ST70 with a PAS 3 preamp. Like a fool I sold it in the 80s and replaced it with a Pioneer SA9100. I realized after I switched that my system didn't sound as good as it used to.
Am glad you are testing and showing these chinese tube amps...and hope you continue to check some others, like the smaller line magnetic integrated amps or budget musical paradise or ming da's.
Invaluable, detailed information on this tube amp, which I've had an eye on for a couple of months...I am looking forward to your follow up videos on this amp...thank you!
I got my R8 from China-HiFi 20 months ago for US$1,150 including sea shipping and customs clearance. Maybe I just run lucky as none of the problems this channel warns us of appeared. Sonically the R8 with even its KT88 stock tubes beats my vintage Denon DAP5500+POA6600 separates hands down, not to mention my Harman Kardon AVR7200 receiver. I paired it with my classic JBL L7 towers as well as modern budget bookshelvers like the Triangle BR03, Wharfedale Diamond 12.2 and Klipsch RP600M -- all with good synergy. For sources I have a Bluesound Node and Denon's vintage flagship DCD3500RG CD Player, used as a transport going through Denafrips' entry level Ares II Dac, another popular ChiFi product. For the first time I came to appreciate what "emotionally engaging" music means ! Skunkie is providing objective anatomy and measurement services no doubt, but those numbers are of reference value at best. After all most layman audio hobbyists listen to music with their ill trained and imperfect ears rather than analytical instruments. Sometimes a judicious dose of MSG by way of pleasing distortions might just make the music sweeter and more palatable ! Kudos to those ChiFi makers that provide enjoyable audio dishes at such affordable prices !
I agree that the R8 out of the box is a very decent performing tube amp. Some folks have been lucky and haven't have the output tube red plate meltdown others have had to deal with. I also had weird ground loop issues with the R8 but again, not all people will have that issue depending on their setup. This video is on the R300 and I can't say the same.
@SkunkieDesignsElectronics As I say, you're providing valuable information. I had been flirting with the idea of getting the R300 for intimate near field listening in my study after seeing those raving reviews from Jay's Iyagi, Steve Huff, Thomas & Stereo et al. Now I'll just put it off for the time being, pending more user feedback...
Those measurement lines, reminds me when I use to drawing on a Etch A Sketch..LOL. I do need to invest in the Analog Discover 2 kit so I will check out your video on what to buy. As I have been upgrading and testing tubes/parts on the R300 (on Audiokarma), let see what you find on this Amp. An issue that has been reported that I know of, "high voltage protection delay circuit" added which Willsenton said will prevent a bad tube (274B) from damaging the circuit board.
It would be interesting to test a high end 300B or classic one to see how they fair in these measurement tests. I can only judge my amp by the sound with my extremely efficient horn loudspeakers which I find very musical and outstanding. Maybe I shouldn’t have watched this, lol, but I’m comfortable in my own listening abilities.
There was a comparison chart to my budget DIY 300B amp in the video that is at 1% distortion up to 6.5W. 23:35 And the square waves are clean. This amp the square waves are bad at 1W of power.
@@SkunkieDesignsElectronics So true. I actually test out at 11K maybe because I’ve always protected my ears from super loud sounds. On another note I want you to know I’ll really respect your work and your opinion and look forward to your actual listening tests. My amp replaced a very high end solid state amp because I wanted to experiment with 300B on my Altec Lansing Valencia 16 ohm loudspeakers. The amp has surpassed my expectations I received from the glowing reviews. I guess it’s a matter of horses for courses type of thing?
You and me both! I honestly don't get it. I would be like raving about some sports car being the fastest ever and then someone puts it on the dyno and it has less power than a Honda civic.
Great video I would love to see you vet a McIntosh 275 vs Orsefon 275 (another china amp) I watched your R8 videos and you nailed it. I had that amp and there was just something missing in the bass
Very professional explanation.That's your mark.I wait the final conclusions because I was interested for Willsenton 300b. I want to know if you compared musically, not technically, Willsenton R8 full Skunkie upgraded with Muzishare 7x? I am very interested to know your opinion. My respect, Steph
I was holding-off purchasing this one - In spite of the glowing reviews on-line. Call me jaded but at that price it seemed too gud to be true. Geeze Lou-wheeze. When I wuz young I fell in luv with a pretty face and O My O My did I learn a tuff lesson. Once bitten - twice shy. Remember that old song, "Never Make A Pretty Woman Your Wife," ??????
My friend's Wilsenton R300 does take a long time to warm up. Like 15 minutes or so. I tell him I think something is wrong. I've owned 3 different 300b's and they were always ready in about 3 to 5 minutes to go.
@@SkunkieDesignsElectronics I have a cheap A10 el34 amp modified by previous owner I like it and I have a very budget gemtune el34 , 5 watts is plenty for my small room , I know you are 100 percent right. I just like the vocals from the 300b amps . And look forward to seeing what you do with this one . Thank you for your videos
Just purchased Analog Discovery 2. I am testing an R300 and get similar results... do you have the BNC probe set to 1X or 10X... i have to set it to 1X otherwise i get terrible readings. My amp has a pretty big difference between channels... and is only putting out about 4W at 2% noise. That is with Psvane 300B-T Mk2 tubes instead of the stock.
Wow, i've never heard one of your amps under test.... a 1k i wasn't sure if it was the video or something else, ince you went to 10k, i could definitely tell it was screaming on the video
@SkunkieDesignsElectronics i built a china kit amp that squealed with no speakers hooked up, well, i didn't build an amp, turns out it's an oscillator... it's sitting in the corner thinking about it's poor life choices
I am owning r300 for last 6 months. Glad reviews like this are showing what this amp. This is junk amp. Had faced too many problems. Tube arcing of rectifier tubes. Loud pops due to bad 6sl7 which was recommended by china hifi to replace tubes. Also suspect too much negative feedback used just can not see any virtues of a good SET amp. I was told that my amp shipped with 5u4g rectifier are faulty and was offerrd to replace for free with 274b which i had replaced stock rectifier with sophia 274b
I couldn't fathom spending $2000cad and then having to replace all of the China tubes to even get close to the spec wattage. The more I've read and watched the more I am glad I stayed away from chifi tube amps.
In my 40+ years in HiFi I’ve never lost $ buying older gear and trading up over time. Good equipment lasts and only becomes more sought after. Wish I could have afforded to keep the stuff I sold on. Some of it is worth double what I sold it for just a few years ago, like a McIntosh MA6200. Killer piece but try to find one now for a $1,000. Can’t see this Chinese stuff ever being worth much.
@@SkunkieDesignsElectronics exactly, won't find many Willsentons kicking around antique markets in 50 years like you do the old RCA Victor cabinets stereos.
Honestly never listened to them and unless I owned a several thousand dollar amp with SUPER high end output transformers etc, I'd never bother. I do like the sound of the 300B-Z treasure tubes if you can find some.
That 10K square wave ... Good grief, I've seen guitar amps with a single tone control do better. What's up with that? Has anyone depotted any of these Chinese outputs to see what's really in there? As some here may know the Heath W3 and W4 (maybe W5 too, can't remember now) suffered from blown power transformers. When the wife wasn't around I put one in the kitchen oven and supported the can flanges on a couple of bricks. A couple of hours later, voila, out slid the teeny TINY transformer out of that BIG can. Suspicions confirmed! Keep up the good work Steph. You're killin it!
PS Steph ... It's time for a better signal generator. I bought a used BK 4003A for $50 locally. Will give you a perfect sine and square wave at any audio frequency- and do a lot more. Food for thought. Even a handheld Tenma 72-505 will do the job, limited in the output voltage though.
Yeah I need to get a new one. I might even play with trying to use the one in the Analog discovery 2, or even just figure out how to use the scope in it.
Dubble dip = output transformer with multiple hf resonances instead of a gradual smooth roll off , nasty caracyer with implications on music and staility ! ( Very cheap/bad OPT ) WHO buys these Things , how come reviewers don't mentions these low quality and bad performance !? Thanks for telling the truth and informing pôtential buyers ......
Most tube amp manufacturers seem to rate their power at 10% THD. Look at the measurements that Stereophile does when their standard is 1% THD. When they change it to 10% THD they usually come close to their power specifications. This is almost standard with all tube amp companies regardless of what country they are manufactured in.
So when the manufacturer says 8W at 1% THD in the ad, they really meant 10% and just forgot to add the zero? I don't see other legit tube manufacturers rating their power at 10% THD and deep into clipping.
The clipping point is good for deciding where it's going to sound audibly very bad. I can't imagine anyone trying to claim past the clipping point sounds good. I've seen plenty of amps create 2%-5% distortion and still not be into clipping.
There are tons of reviews of this amp on TH-cam.. All saying this one is very good.. I have been saving up for my soundsystem and based on those reviews.. The Wilsenton r800i seemed to be the best... I'm not sure where to place those reviews now...
It's not a bad sounding amp, and I'm not sure what you could buy for $1500 that would sound better. But don't think you are getting the sound and reliability of a $3000 amp for $1500.
@@SkunkieDesignsElectronics If I was going to get one. I was going to gradually upgrade the tubes. A step up each time. Would getting better than stock tubes help it perform better with these tests?
Replace the 274B tubes with 5U4G, or better still, the St. Petersburg Svetlana 5Ц3C black-plates. 160mA vs 250mA. Doing this may give you closer to the rated output. Still, the square wave, especially at 10K is ridiculously bad, as is the frequency response falling off a cliff at 10K!
But 300b tubes only run at ~75ma each and that is split across two 160ma rectifiers = 320ma. My 300b amp runs on a single 5AR4.. I plan to address the power supply but I don't think that is going to change the power output.
@@SkunkieDesignsElectronics - Yes, I agree, but there is something very special about the St. Pete Svet 5U3C black-plates (foil getter version made in the 50s and 60s - the tube, thankfully, is still readily available). I know, it makes no logical sense, but the Willsenton R800i which also uses 300B tubes, but In combination with 805A tubes on the output, comes standard with one 274B tube. When it is changed to the Svet black-plate, the sound is instantly more open and dynamic. To say it's magic, I know, sounds ridiculous, but nonetheless, something is very special about using these Svets as the full wave rectifier, and not just in the R800i! Someone I know who uses a DIY pair of 300B monoblocks changed his 5U4Gs to the Svets and his comment was that the sound improved in such a way that he said to me, "It sounds like my monos can breathe now!" On another note, I use the Takatsuki TA-300B in my R800i, and wow; what a beautiful sounding 300B, and even better with the Svet.😀 Honestly - true story!
17Vpp is 6Vrms. 6 times 6, then divide by 8 = 4.5. After replacing all the tubes: 21Vpp is 7.4Vrms. Same calculation come to 6.8W. That's where the amp starts clipping with the stock tubes, and then with upgraded ones.
@@SkunkieDesignsElectronics Well that should eliminate nasty impedance swings that possibly could affect the poor measurements. A set of speakers could make the measurements look even worse. Look forward to see what you find and if there are improvements to be made. Thanks.
@@SkunkieDesignsElectronics That amplifier has a lot of noise going on and I believe you're definitely going to hear it in the speakers.... It makes me think there is a bad filter cap somewhere....? who knows ? Can't wait to see what you find lol
@@SkunkieDesignsElectronics Another thing that you might want to check, that is kind of crazy, is to see if the power transformer and the audio transformers (because they are mounted close to each other) are out of phase with one another.... in other words, if the audio transformers are placed or mounted in the wrong direction to the power transformer that will create a high frequency to low frequency hum or noise... sort of like an oscillating noise because they're out of phase with one another.... also.... a bad ground or ground loops will also create a hum or noise. I'm still thinking that it's a bad filter cap somewhere because placing those audio transformers in the wrong direction to the power transformer is a No No that every manufacturer of tube amps should know...
Obviously Chinese manufacturing quality is not very good. That doesn't mean they don't know that. The specific amp tested may have problems known to Willsenton, but even so they'll ship it anyway. Chinese manufacturers will not trash anything defective, they'll just sell it on and the buyer beware. I wonder if Thomas and Stereo knows about these measurements. He praised the amp to the skies, and claims several of his friends reacted the same way.
I said it's better than a R8 :) I would not call the X7 an excellent amp, an excellent amp doesn't need the power caps replaced to the correct voltage ones.
Indeed the right word you chose is GARBAGE ....if someone has bought one , sell it or use the chassis to build your own amplifier ( change OPT's for some quality ones ) Guess how much amplifiers this hyped brand sold worldwide..........
Stephe, many thanks for your work on analyzing this amp🙏🏻 Out of the box the amps looks like a total mess.
Hopefully only little modifications could turn it to a „normal performing“ 300B amp.
Looking forward to all your next videos.
I hope so too!
Im looking forward to the rest this series!!
Thank you for a really straight presentation Stephe. It is going to be very interesting to see what happens from here
Love this, one hot mess lol. Here in Canada these amps are $2,000, not cheap especially for only 8 watts. No sugarcoating that this is money wasted.
This sure beats some reviewer saying the amp sounds pretty good for the money.
You make these videos interesting for those who don’t get it. 👏
That's just all your going to get for a class a 300b no matter if you spend $2k or $20k that's all your going to get from a 300b class a
yeah but it shouldn't have this much distortion and the craziness at 10K. My super budget DIY build, designed by a hobbyist in their basement, performs way better! And it only really makes around 5W with all the tubes replaced, which adds several hundred $.
@@SkunkieDesignsElectronics I completely agree , but I also believe it's solid start and that when your done it will something special. , I don't mind making few mods to a amp but building from scratch not really something I'm comfortable with .... Yet ...
From my little understanding it’s not just swapping out components for better quality it’s the
overall design that makes an amp sing. It’s not that simple.
Are these Chinese amplifiers just trying to copy old designs and failing miserably?
I have no idea, I certainly wouldn’t risk smoking my expensive speakers playing around with this stuff. 🫣
I'm scared to put my good 300B tubes in it. On a forum I follow, one of these amps redplated a brand new gold lion 300B tube, which if it didn't kill it, took a large % of it's life. That's a $220 tube. Note I had to put $400 worth of 300B tubes and another $150 of NOS driver tubes in it to even come close to performing decently. And the way this amp slams the B+ into the tubes, they probably aren't gonna last long.
Thank you and yes, I am loving this content. I recently bought this amp and, like others, think it sounds good. Must be the tube harmonics. However, doesn't mean that it can't sound better, maybe way better, and I will probably perform any change or upgrade that SDE recommends.
Is this your first tube amp? Just curious.
@@SkunkieDesignsElectronics Well, yes and no. First tube amp in 30 years. My first ever amp was a Dynaco ST70 with a PAS 3 preamp. Like a fool I sold it in the 80s and replaced it with a Pioneer SA9100. I realized after I switched that my system didn't sound as good as it used to.
So yeah, compared to a sterile SS amp, it probably does sound good.
The more videos I watch of yours, the happier I am that I sold my Willsenton.
They are not manufacturing very good products, that's for sure!
One heck of a notch filter in the signal path. It would be interesting to find out what is under those transformer covers. Especially those outputs.
Am glad you are testing and showing these chinese tube amps...and hope you continue to check some others, like the smaller line magnetic integrated amps or budget musical paradise or ming da's.
I'm testing what viewers are willing to send to me for testing/upgrades.
Invaluable, detailed information on this tube amp, which I've had an eye on for a couple of months...I am looking forward to your follow up videos on this amp...thank you!
I got my R8 from China-HiFi 20 months ago for US$1,150 including sea shipping and customs clearance. Maybe I just run lucky as none of the problems this channel warns us of appeared. Sonically the R8 with even its KT88 stock tubes beats my vintage Denon DAP5500+POA6600 separates hands down, not to mention my Harman Kardon AVR7200 receiver. I paired it with my classic JBL L7 towers as well as modern budget bookshelvers like the Triangle BR03, Wharfedale Diamond 12.2 and Klipsch RP600M -- all with good synergy. For sources I have a Bluesound Node and Denon's vintage flagship DCD3500RG CD Player, used as a transport going through Denafrips' entry level Ares II Dac, another popular ChiFi product. For the first time I came to appreciate what "emotionally engaging" music means ! Skunkie is providing objective anatomy and measurement services no doubt, but those numbers are of reference value at best. After all most layman audio hobbyists listen to music with their ill trained and imperfect ears rather than analytical instruments. Sometimes a judicious dose of MSG by way of pleasing distortions might just make the music sweeter and more palatable ! Kudos to those ChiFi makers that provide enjoyable audio dishes at such affordable prices !
I agree that the R8 out of the box is a very decent performing tube amp. Some folks have been lucky and haven't have the output tube red plate meltdown others have had to deal with. I also had weird ground loop issues with the R8 but again, not all people will have that issue depending on their setup. This video is on the R300 and I can't say the same.
@SkunkieDesignsElectronics As I say, you're providing valuable information. I had been flirting with the idea of getting the R300 for intimate near field listening in my study after seeing those raving reviews from Jay's Iyagi, Steve Huff, Thomas & Stereo et al. Now I'll just put it off for the time being, pending more user feedback...
There is an active discussion with users here
www.stereonet.com/forums/topic/574308-willsenton-r300-owners-discussion-thread
@@SkunkieDesignsElectronics Thanks 😊
Those measurement lines, reminds me when I use to drawing on a Etch A Sketch..LOL. I do need to invest in the Analog Discover 2 kit so I will check out your video on what to buy. As I have been upgrading and testing tubes/parts on the R300 (on Audiokarma), let see what you find on this Amp. An issue that has been reported that I know of, "high voltage protection delay circuit" added which Willsenton said will prevent a bad tube (274B) from damaging the circuit board.
The kit is linked in the description, and is on sale! That kit + a pair of 8 ohm dummy loads and you are all set.
Excellent testing as always. Many thanks.
Great technical test and info! Keep up the good work. Very interesting and informative. Thanks
Steph's gonna gut this thing. Dang and I had high hopes out of the box for this amp.
So did I! I have so many other projects to work on lol.
I am so happy I bougt a Muzishare! Ordered all the tubes you recommended 🙂
It would be interesting to test a high end 300B or classic one to see how they fair in these measurement tests. I can only judge my amp by the sound with my extremely efficient horn loudspeakers which I find very musical and outstanding. Maybe I shouldn’t have watched this, lol, but I’m comfortable in my own listening abilities.
There was a comparison chart to my budget DIY 300B amp in the video that is at 1% distortion up to 6.5W. 23:35
And the square waves are clean. This amp the square waves are bad at 1W of power.
@@SkunkieDesignsElectronics Thanks. I’ll be following this series. Maybe my 75 year old ears don’t miss those high rolled off frequencies.
You likely don't hear anything past 8K, just the facts when we age.
@@SkunkieDesignsElectronics So true. I actually test out at 11K maybe because I’ve always protected my ears from super loud sounds. On another note I want you to know I’ll really respect your work and your opinion and look forward to your actual listening tests. My amp replaced a very high end solid state amp because I wanted to experiment with 300B on my Altec Lansing Valencia 16 ohm loudspeakers. The amp has surpassed my expectations I received from the glowing reviews. I guess it’s a matter of horses for courses type of thing?
IMHO almost any tube gear sounds more pleasing to my ear than SS gear.
Great info as usual, I always find it interesting how all the reviewers can keep saying this stuff is great, shocking poor.
You and me both! I honestly don't get it. I would be like raving about some sports car being the fastest ever and then someone puts it on the dyno and it has less power than a Honda civic.
Great video
I would love to see you vet a McIntosh 275 vs Orsefon 275 (another china amp)
I watched your R8 videos and you nailed it. I had that amp and there was just something missing in the bass
Maybe one day!
Very professional explanation.That's your mark.I wait the final conclusions because I was interested for Willsenton 300b.
I want to know if you compared musically, not technically, Willsenton R8 full Skunkie upgraded with Muzishare 7x?
I am very interested to know your opinion.
My respect, Steph
Yes I did a video on the listening session with both the R8 and the X7, the X7 came out on top.
I was holding-off purchasing this one - In spite of the glowing reviews on-line. Call me jaded but at that price it seemed too gud to be true. Geeze Lou-wheeze. When I wuz young I fell in luv with a pretty face and O My O My did I learn a tuff lesson. Once bitten - twice shy. Remember that old song, "Never Make A Pretty Woman Your Wife," ??????
To get a better looking square wave on the scope at low frequencies set the scope to DC. On my Tektronix 2445A it makes a noticeable difference.
Thanks for the tip, I will try that!
My friend's Wilsenton R300 does take a long time to warm up. Like 15 minutes or so. I tell him I think something is wrong. I've owned 3 different 300b's and they were always ready in about 3 to 5 minutes to go.
That doesn't sound right to me either.
@@SkunkieDesignsElectronics He is sending it back for them to look at it.
I'm still very interested in this amp !! Love that it has a remote ! But I'm waiting to find one under $1000 .
Hmm I honestly think there are better options.
A Dynaco ST-70 modified would be a better investment.
An EL34 SE amp will make more power than this amp makes out of the box, and the tubes are 10% of the cost.
@@SkunkieDesignsElectronics You are abselutly right and thank you to debonke that hype.
@@SkunkieDesignsElectronics I have a cheap A10 el34 amp modified by previous owner I like it and I have a very budget gemtune el34 , 5 watts is plenty for my small room , I know you are 100 percent right. I just like the vocals from the 300b amps . And look forward to seeing what you do with this one . Thank you for your videos
Just purchased Analog Discovery 2. I am testing an R300 and get similar results... do you have the BNC probe set to 1X or 10X... i have to set it to 1X otherwise i get terrible readings. My amp has a pretty big difference between channels... and is only putting out about 4W at 2% noise. That is with Psvane 300B-T Mk2 tubes instead of the stock.
Yes absolutely must use 1X on the probe. And yeah I think what you are seeing is what most people would find. More work on this issue soon!
Wow, i've never heard one of your amps under test.... a 1k i wasn't sure if it was the video or something else, ince you went to 10k, i could definitely tell it was screaming on the video
And that's into a dummy load....
@SkunkieDesignsElectronics i built a china kit amp that squealed with no speakers hooked up, well, i didn't build an amp, turns out it's an oscillator... it's sitting in the corner thinking about it's poor life choices
Swap the output transformer output leads and I bet that stops.
Interesting video. What harmonics were the distortion?
Once it was past 1%, it was across the board.
I am owning r300 for last 6 months. Glad reviews like this are showing what this amp. This is junk amp. Had faced too many problems. Tube arcing of rectifier tubes. Loud pops due to bad 6sl7 which was recommended by china hifi to replace tubes. Also suspect too much negative feedback used just can not see any virtues of a good SET amp. I was told that my amp shipped with 5u4g rectifier are faulty and was offerrd to replace for free with 274b which i had replaced stock rectifier with sophia 274b
I've watched some of those reviews on this amp and they sound like salesmen at a hifi store.
Stephe, what rectifier tube did you use? 274Bs or 5U4Gs. Thank you!
The tubes it came with, 274B. A rectifier tube is not going to cause the amp to create square waves like this.
Looks like they changed rectifier tubes from 5u4g to 274b then. Mine bought in nov 2022 came with 5u4g
@@muralimmreddycurrently you can choose between Willsenton 274Bs and EH5U4GBs….
I couldn't fathom spending $2000cad and then having to replace all of the China tubes to even get close to the spec wattage. The more I've read and watched the more I am glad I stayed away from chifi tube amps.
Yep, add $550 min and that's not replacing the rectifier tubes, which are driven way out of spec.
In my 40+ years in HiFi I’ve never lost $ buying older gear and trading up over time. Good equipment lasts and only becomes more sought after.
Wish I could have afforded to keep the stuff I sold on. Some of it is worth double what I sold it for just a few years ago, like a McIntosh MA6200. Killer piece but try to find one now for a $1,000. Can’t see this Chinese stuff ever being worth much.
It won't be. This surely isn't "investment grade" audio gear.
@@SkunkieDesignsElectronics exactly, won't find many Willsentons kicking around antique markets in 50 years like you do the old RCA Victor cabinets stereos.
Out of topic maybe, how would you rate a Western Electric new issue 300B @700U.S.$ a piece compare to ,well what is available?
Honestly never listened to them and unless I owned a several thousand dollar amp with SUPER high end output transformers etc, I'd never bother. I do like the sound of the 300B-Z treasure tubes if you can find some.
@@SkunkieDesignsElectronics TKS
That 10K square wave ... Good grief, I've seen guitar amps with a single tone control do better. What's up with that? Has anyone depotted any of these Chinese outputs to see what's really in there? As some here may know the Heath W3 and W4 (maybe W5 too, can't remember now) suffered from blown power transformers. When the wife wasn't around I put one in the kitchen oven and supported the can flanges on a couple of bricks. A couple of hours later, voila, out slid the teeny TINY transformer out of that BIG can. Suspicions confirmed! Keep up the good work Steph. You're killin it!
PS Steph ... It's time for a better signal generator. I bought a used BK 4003A for $50 locally. Will give you a perfect sine and square wave at any audio frequency- and do a lot more. Food for thought. Even a handheld Tenma 72-505 will do the job, limited in the output voltage though.
Yeah I need to get a new one. I might even play with trying to use the one in the Analog discovery 2, or even just figure out how to use the scope in it.
@@SkunkieDesignsElectronics Nothing like a good old analog scope! Smooooooth. Your 2235 seems to work fine!
I wish I could find a BK 4003A for $50 lol
Dubble dip = output transformer with multiple hf resonances instead of a gradual smooth roll off , nasty caracyer with implications on music and staility ! ( Very cheap/bad OPT )
WHO buys these Things , how come reviewers don't mentions these low quality and bad performance !?
Thanks for telling the truth and informing pôtential buyers ......
Please review Vincent SV 237mk or any of the Vincent integrated hybrids.
Send me one and I will :)
Most tube amp manufacturers seem to rate their power at 10% THD. Look at the measurements that Stereophile does when their standard is 1% THD. When they change it to 10% THD they usually come close to their power specifications. This is almost standard with all tube amp companies regardless of what country they are manufactured in.
So when the manufacturer says 8W at 1% THD in the ad, they really meant 10% and just forgot to add the zero? I don't see other legit tube manufacturers rating their power at 10% THD and deep into clipping.
10% distortion is a good figure for a guitar amp to be making delicious crunchy tones.
10% for making music.
The clipping point is good for deciding where it's going to sound audibly very bad. I can't imagine anyone trying to claim past the clipping point sounds good. I've seen plenty of amps create 2%-5% distortion and still not be into clipping.
There are tons of reviews of this amp on TH-cam.. All saying this one is very good.. I have been saving up for my soundsystem and based on those reviews.. The Wilsenton r800i seemed to be the best...
I'm not sure where to place those reviews now...
It's not a bad sounding amp, and I'm not sure what you could buy for $1500 that would sound better. But don't think you are getting the sound and reliability of a $3000 amp for $1500.
@@SkunkieDesignsElectronics If I was going to get one. I was going to gradually upgrade the tubes. A step up each time. Would getting better than stock tubes help it perform better with these tests?
Right as I ask the video then covers it... Nvm.
lol that's why i bought fm300a clone instead of tube following the german youtuber's advice, less hassle to worry about
Replace the 274B tubes with 5U4G, or better still, the St. Petersburg Svetlana 5Ц3C black-plates. 160mA vs 250mA. Doing this may give you closer to the rated output.
Still, the square wave, especially at 10K is ridiculously bad, as is the frequency response falling off a cliff at 10K!
But 300b tubes only run at ~75ma each and that is split across two 160ma rectifiers = 320ma. My 300b amp runs on a single 5AR4.. I plan to address the power supply but I don't think that is going to change the power output.
@@SkunkieDesignsElectronics - Yes, I agree, but there is something very special about the St. Pete Svet 5U3C black-plates (foil getter version made in the 50s and 60s - the tube, thankfully, is still readily available). I know, it makes no logical sense, but the Willsenton R800i which also uses 300B tubes, but In combination with 805A tubes on the output, comes standard with one 274B tube. When it is changed to the Svet black-plate, the sound is instantly more open and dynamic. To say it's magic, I know, sounds ridiculous, but nonetheless, something is very special about using these Svets as the full wave rectifier, and not just in the R800i! Someone I know who uses a DIY pair of 300B monoblocks changed his 5U4Gs to the Svets and his comment was that the sound improved in such a way that he said to me, "It sounds like my monos can breathe now!"
On another note, I use the Takatsuki TA-300B in my R800i, and wow; what a beautiful sounding 300B, and even better with the Svet.😀 Honestly - true story!
Cold solder joint on one of the output tube sockets?
Both channels tested the same, showed that in the video.
Hi id like to know how you make the calculation about 17 v peak to to peak into 8 ohm =4.5 watt .thanks
17Vpp is 6Vrms. 6 times 6, then divide by 8 = 4.5.
After replacing all the tubes: 21Vpp is 7.4Vrms. Same calculation come to 6.8W.
That's where the amp starts clipping with the stock tubes, and then with upgraded ones.
ok thanks a lot@@SkunkieDesignsElectronics
on the square wave its bad ringing to do with the output transformer
That's my guess as well, but it also could be horribly designed GNFB
What are you using as load on the output?
8ohm dummy loads designed for audio testing.
@@SkunkieDesignsElectronics Well that should eliminate nasty impedance swings that possibly could affect the poor measurements.
A set of speakers could make the measurements look even worse.
Look forward to see what you find and if there are improvements to be made.
Thanks.
Wow..... ! Never seen a square wave that BAD ! Maybe bad tubes ?
Later in the video I replaced all the tubes... Same crazy square wave.
@@SkunkieDesignsElectronics Yes... I watched the rest of the video......
@@SkunkieDesignsElectronics That amplifier has a lot of noise going on and I believe you're definitely going to hear it in the speakers.... It makes me think there is a bad filter cap somewhere....? who knows ? Can't wait to see what you find lol
I wanna dive deeper into the noise+THD stuff too, testing a few other amps against this one.
@@SkunkieDesignsElectronics
Another thing that you might want to check, that is kind of crazy, is to see if the power transformer and the audio transformers (because they are mounted close to each other) are out of phase with one another.... in other words, if the audio transformers are placed or mounted in the wrong direction to the power transformer that will create a high frequency to low frequency hum or noise... sort of like an oscillating noise because they're out of phase with one another.... also.... a bad ground or ground loops will also create a hum or noise. I'm still thinking that it's a bad filter cap somewhere because placing those audio transformers in the wrong direction to the power transformer is a No No that every manufacturer of tube amps should know...
Obviously Chinese manufacturing quality is not very good. That doesn't mean they don't know that. The specific amp tested may have problems known to Willsenton, but even so they'll ship it anyway. Chinese manufacturers will not trash anything defective, they'll just sell it on and the buyer beware. I wonder if Thomas and Stereo knows about these measurements. He praised the amp to the skies, and claims several of his friends reacted the same way.
Didn't these same reviewers praise the Reisong A50 and A12?
That's Russian tubes Tung-Sols, Gold Lion, they never throw out tubes which pass with only 30% and under tube life.
Why was this amp so favorably reviewed by others?
Those same folks raved about both those crappy Reisong amps.
@@SkunkieDesignsElectronics it makes me very cautious to trust anything which is said on those channels. I don't know what else to think.
I am suspicious of any reviewer who only has glowing reviews of every product they test.
And I got attacked in the comments for not posting glowing reviews on everything lol
I said it's better than a R8 :) I would not call the X7 an excellent amp, an excellent amp doesn't need the power caps replaced to the correct voltage ones.
Despite being far from perfect, I can take satisfaction that at least the R8 isn't this bad.
In fact the objective performance of the R8 was quite good and right in line with their advertised specs..
It gets such good reviews too from the "Audiophiles" . A stinking mess it seems in reality.
Wow! That thing must sound aggressive as hell according to your tests. 😁An old Dynaco st 70 would be a better deal than that piece of junk.
Objective testing is not good so the question must be asked. Why did the subjective reviewers love how it sounded?
Those same guys praised the Reisong A50 last round of china amp reviews... I have no idea why they keep doing this.
Interestingly they didn't review any competing products...
I am not a tech, but I know that is messed up.
Yikes, what a hot mess! Chifi strikes again, except in a few cases that are built well.
Agreed AND there are a lot of reports of these things eating rectifier tubes, so the power supply is also a mess.
Square wave shows that phase margin is close to 50 degrees, not so stable amplifier 😮😮
Yup
Indeed the right word you chose is GARBAGE ....if someone has bought one , sell it or use the chassis to build your own amplifier ( change OPT's for some quality ones )
Guess how much amplifiers this hyped brand sold worldwide..........