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Partial tear down of Willsenton R8


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@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.

 

 

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I am not an expert on tube amp like many on this forum however writing this blog to help those who are thinking of buying Willsenton R8 or those who owns it and want to know bit more about it. I am no

The Melz 1578s arrived today and boy are they neat! For those that don't know, they were developed for Soviet era nuclear facilities and military applications. Here's a pic of them warming up in the R

You are correct.  Everything goes through 12AX7 which is a preamp tube.   The PRE IN has 47K in series resistor to drop the signal level. When S2 is turned on, RL1 takes input directly from

@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!

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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 😛)

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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.

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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.

 

 

506344973_thumbnail(2).jpg.b67114e99e19ff49a398510c5c9fc791.jpg

 

 

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.

 

139236326_thumbnail(1).jpg.3f5e58163230d31b7b0710df3869781a.jpg

 

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. 🙂

 

 

 

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@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!

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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.

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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!

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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 🙂

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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...

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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.

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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...

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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.

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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.

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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.

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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.

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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?

 

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@demoiree V1 gets full current regardless of tube. When it first happened (last month or so), I was using KT88. There's something wrong related to that valve position. I hope its an easy fix and that the transformer isn't damaged or something. Very nervous...

 

WOW - Well, since the R8 is broken, I plugged my A-S2100 integrated back in today. It is the first time I have listened solid state in several months. There's just no contest for holography, 3D mids, and air. The R8 absolutely smokes it in these regards. The A-S2100 has more detail and is quicker, but the soundstage sounds flat and boring by comparison and the midrange magic is not there. It doesn't reach out and grab you. Interestingly, the center image between the speakers seems much smaller too, though the peripheral width is about the same as the R8. The R8 has a more even and natural soundstage compared to it. Very interesting... Also interesting, I compared the stock R8 and A-S2100 on the first days of having the R8. Back then, the R8 had a smaller soundstage than the A-S2100 and was harsh. Plugging the A-S2100 back in today confirms that much has changed with the R8 since those first weeks. It all just makes me sadder that my R8 is down, though.

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4 minutes ago, echorec said:

@demoiree V1 gets full current regardless of tube. When it first happened (last month or so), I was using KT88. There's something wrong related to that valve position. I hope its an easy fix and that the transformer isn't damaged or something. Very nervous...

 

WOW - Well, since the R8 is broken, I plugged my A-S2100 integrated back in today. It is the first time I have listened solid state in several months. There's just no contest for holography, 3D mids, and air. The R8 absolutely smokes it in these regards. The A-S2100 has more detail and is quicker, but the soundstage sounds flat and boring by comparison and the midrange magic is not there. It doesn't reach out and grab you. Interestingly, the center image between the speakers seems much smaller too, though the peripheral width is about the same as the R8. The R8 has a more even and natural soundstage compared to it. Very interesting... Also interesting, I compared the stock R8 and A-S2100 on the first days of having the R8. Back then, the R8 had a smaller soundstage than the A-S2100 and was harsh. Plugging the A-S2100 back in today confirms that much has changed with the R8 since those first weeks. It all just makes me sadder that my R8 is down, though.

 

I hope just a simple issue with resistors or caps ! 

 

maybe is a good time to swap out those willsenton caps to better ones mundorf or jantzen:)

 

 

 

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3 minutes ago, demoiree said:

 

I hope just a simple issue with resistors or caps ! 

 

maybe is a good time to swap out those willsenton caps to better ones mundorf or jantzen:)

 

 

 

Not really, unless those caps are an issue. However I don't think those caps are the reason for this high current. There must be some faulty components in negative grid supply voltage specifically for V1 which is causing too much negative voltage in the grid causing high current. I suspect the filter caps/diodes on that circuit.

 

 

thumbnail (3).jpg

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I wonder, since this problem previously went away and resurfaced, if there could be a cold/loose solder joint somewhere in the filter caps/diodes section. Perhaps the joint finally broken clean? I don't know what I talking about though 😆

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9 minutes ago, echorec said:

I wonder, since this problem previously went away and resurfaced, if there could be a cold/loose solder joint somewhere in the filter caps/diodes section. Perhaps the joint finally broken clean? I don't know what I talking about though 😆

Oh dear.. I hope you can get it fixed. 

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35 minutes ago, echorec said:

I wonder, since this problem previously went away and resurfaced, if there could be a cold/loose solder joint somewhere in the filter caps/diodes section. Perhaps the joint finally broken clean? I don't know what I talking about though 😆

That is something you can try yourself if you are handy with soldering. Absolutely no harm in doing that. Just re-solder all the points around that valve base and bios pcb as I pictured above.

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I decided to look myself and see if there is anything obvious. Check this out - There is NO SOLDER on one of the connections on the rear power tube selector switch. I don't suppose this could have anything to do with my problem could it?

 

 

R8-Solder-Missing.jpg

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By the way, is there any non invasive testing I can do to troubleshoot the V1 section using my multimeter? As I understand it, capacitors must be removed from the circuit to test them properly and I don't want to do that. But I'm wondering if there is anything else I can test without risking any damage (resistors or diodes?). I don't feel comfortable doing any soldering. Thanks so much for your time!

 

 

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No soldering?

 

Not much you can do apart from checking continuity of connections with a DMM, but that may not help with intermittent connection issues.

 

Needs to looked at by someone with the skill and knowledge to find the fault and repair.

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1 hour ago, echorec said:

I decided to look myself and see if there is anything obvious. Check this out - There is NO SOLDER on one of the connections on the rear power tube selector switch. I don't suppose this could have anything to do with my problem could it?

 

 

R8-Solder-Missing.jpg

The photo is not clear to me but if you see no solder there, that might be the issue. However, DON'T GO ON WITH MULITIMETER AND CHECKING STUFF UNDERNEATH IF YOU DON'T KNOW TUBE AMP. There are lethal voltages involved. Please be careful mate. 

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Yes, never while powered up or plugged in, and without first checking that the power supply capacitors are drained of charge.

 

Edit: Pretty fruitless without the knowledge around trouble shooting and repair, for example even if something is obvious like a burned resistor in the power supply, just changing that resistor does not address the reason it burned.

 

 

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Bummer to read of your issue @echorec. Hoping you get it sorted quickly.  I guess this will test the warranty follow up etc too.  I am sure Yong will be helpful but yes, the geographical distance will push options available.  The website does clearly state warranty is no issue outside of China so if thats through their preferred fixxer or your preferred fixxer with the cost being covered I am sure will explored. 

 

On a happier note, mine finally arrived.  Packaged like a champion and the smell of fresh paint once I unboxed it was insanely strong.

 

All plugged in and working perfectly.  Checked the bias, was a bit high and just pegged it back a bit and now all good.

About 5hrs of listening thus far, very nice.  I am sure it will get better after maybe 20-30hrs as a minimum.  But right out of the box I am happy with the bass and also the higher frequencies, nothing brittle and bass is quite stong.  Wouldnt say soundstage is mind blowing just yet but I can hear the depth in it, just need it to open a little and then the width will be there too.

All tubes are standard, the KT88 I was unsure whether to go for based on some reviews saying the EL34 is a slightly smoother sound but I went with KT88 and will over time roll through the varying options.

As this was a unexpected gift I just plan to enjoy it for a while and leave it as it is till its all burnt in and operating at capacity. Unless the tubes foul up I dont expect to change anything until maybe early next year, but with all the rolling in this thread already it will be a great reference bank on what tubes power and pre to consider when I do decide to go shopping!

 

Here are some pics...

 

 

 

 

 

3.jpg

1.jpg

2.jpg

Edited by 08Boss302
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Thanks, everyone! I double checked that solder connection pictured above and there must be a very tiny amount of solder holding the wire to the post as the wire does not move. It definitely needs to be resoldered though. I just closed it up and am planning on taking it in for repair locally on Tuesday. I'll let the local expert take it from here.

 

@08Boss302 Congrats! Let us know what you think as time goes by. It will get better!

 

 

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@echorec

Hey mate,

Here are schematic. I have attached Original as well as one I drew after opening. The values are different nothing else and some details of Tube switching is not included in both but that does not matter much as it only changes the grid voltage.

Re_DrawnWithActualComponent.png

R8原理图-NO SHARE.pdf

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@Atmaj thanks for sharing the schematics! 

 

just curious have you done some measuring if the B+ voltage? is it around 445V? so when biasing KT88 should be around 55ma(70% dissipation)  ? 

 

 

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2 minutes ago, demoiree said:

@Atmaj thanks for sharing the schematics! 

 

just curious have you done some measuring if the B+ voltage? is it around 445V? so when biasing KT88 should be around 55ma(70% dissipation)  ? 

 

 

I did measured all the B+ voltages (with 244V grid supply) which are there in the schematic however, I haven't noted down the Bias current measurements. Should have done that but it took long time to note values of all components and draw schematic. I roughly recall it to be 47ma but not 100% sure about it.

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1 hour ago, 08Boss302 said:

 

On a happier note, mine finally arrived.  Packaged like a champion and the smell of fresh paint once I unboxed it was insanely strong.

 

 

 

 

 

Congrats on your purchase!! I was also impressed with the packaging, esp the foam cut out that fits all the tubes snugly. But man.. that smell was insane. I had to put the box and all its trimmings in the sideyard and the machine had enough juice to perfume the room for the next few days. 

 

Having that tube database is a good idea. 

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I am feeling so lucky that like some of you guys, I did not have hot tube issue or any noise issue even after rolling so many tubes.

 

The best part is that smell...... I did have tiny bit smell first time I turned it on for about 10 to 15 mins but nothing so bad (or do I really need to see a nose specialist? 😛)

 

These replaciable tubes are listed in the user manual as well. However there are few more you can use like 6L6 in EL34 mode. Ideally EL34 and KT88 are kind of family of tubes and there are few interchangeable tube types available for each family. 

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Hahahaha No need to see a nose specialist but our house pets were so intrigued with the smell that they kept sniffing the amp and the tubes (when they're not on). Think they were getting a bit high. 

 

Its great that this thread is now 5 pages!! Well done @Atmaj!!

 

My humming 6SL7 tubes are finally resolved. Originally China HiFi sent replacements but they hummed at both speakers rather than just the right side. I just resigned myself and today a package came from China with another set of 6SL7s!! The missus was like.. what did you buy again?? 

 

Hooked them up and both speakers are silent. 

 

Strange and I wonder if the tube measurements play a part or its just a quality issue. The first set of tubes measured 2.5mA, second set was 1.5mA and now 2.2mA. So much variability.. 

 

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      Item Condition: Very Good Shipping Options: Shipping is available at agreed cost. Suburb or Town: Melbourne State: Victoria Payment Method: EFT Reason for selling: NLR Further information:
      Selling my Bob Carver 350 Mono Amplifier, the amplifier was custom made in 240 Volts specifically so there is no need for a step down transformer. The condition is excellent hardly used, build quality is super,and each amplifier is individually handcrafted in the USA by "Tubular" Joe Bonin. Both amplifiers are finished in a lovely crimson red colour which looks absolutely superb.  Due to inherent design of the amplifier the Power Tubes which are the KT120 have a increased lifespan and run much cooler. 
       
      In terms of power, the amplifiers are rated at 350 into 8 and 400 into 4 more than enough power to drive the most difficult of speakers. I have all the original packaging so shipping should not be a problem. 
       
      If you have any questions or would like further information please do not hesitate to contact me.
       
      Price is Negotiable.
       
      PLEASE READ
      If you are advertising multiple items, you must post one bulk price only, or post seperate ads for each item If you include any reference to pricing whatsoever in this section (excluding RRP), your ad will not be approved If you don't include photographs of the actual item being sold, your ad will not be approved










    • By Atmaj
      Item Condition: Used Shipping Options: Pickup available but audition is not available. Suburb or Town: NARRE WARREN State: Victoria Payment Method: Cash on Pickup Reason for selling: Upgrading Further information:
      Up for sale is Yaqin MC 100B Integrated tube/Valve amplifier in excellent working condition along with $300 worth of upgrade.
      This is a true duel mono block amp having 2 seperate power transformer for each channel (hence there are 4 transformer rather than 3 which are on most of tube amps).
      Pre-amp tubes have been upgraded to Electro Harmonix 12AX7
      Coupling Capacitors have been replaced with Mundorf MCap Supreme 1uf. Capacitors are so big that they had to be mounted on chassis rather than the PCB (check photos).
      These 2 upgrade make this amp comparable to high end tube amplifier.
      A great sounding amplifier, ready to drive any speakers even less efficient speakers.
      FEATURES:
      Preamplifier uses SRPP amplification circuit and Nagao-type inverter, Cathode output circuit to promote.
      TWO connection mode: Ultra Linear Amplifier (UL) and triode (TR).
      Duel Mode: INTEGRATED AMPLIFIER mode or pure Power AMPLIFIER mode.
      The output transformer use audio special alloy and high strength Anaerobic enamel-insulated wire. It uses special coiling process.
      This amplifier is made with audio special Enthusiast electrolytic capacitor (MKP), capacitive cross-linked and high quality metallic resistance.

      SPECIFICATIONS:
      Performance Index
      Output power: 30W×2 (8O) Triode (TR) connection
      60W×2 (8O) Ultralinear (UL) connection
      Distortion: =1.5%
      Signal noise ratio (SNR): =90dB (A)
      Frequency Response: 5Hz~80KHz (-2dB)
      Input sensitivity: INTEGRATED AMPLIFIER mode: 0.25V / Power AMPLIFIER mode: 0.6V
      Vacuum tubes: KT88×4 6SN7×4 12AX7×2 (You can also replace it with 6550EH×4 6N8P×4 6N4×2)
      Dimensions: 390mm x 490mm x 190mm
      Weight: 30kg

      I have original box. Pick up from Narre Warren. Happy to post with buyers expenses and arrangements. 
       

      Photos:






       
      PLEASE READ
      If you are advertising multiple items, you must post one bulk price only, or post seperate ads for each item If you include any reference to pricing whatsoever in this section (excluding RRP), your ad will not be approved If you don't include photographs of the actual item being sold, your ad will not be approved
    • By mbd
      Item Condition: Excellent condition. Has lived most of its life in the box. Shipping Options: Pickup available but audition is not available.,Shipping is available at agreed cost. Suburb or Town: Melbourne State: Victoria Payment Method: Paypal, EFT Reason for selling: NLR Further information:
      I'm doing a bit of a cleanup, and have some gear that has reached the point of needing to be sold (thanks to all the sellers' items on here that have caught my fancy lately).
       
      This MF X-Can V3 was bought over 10 years ago and had its caps and tubes upgraded prior to purchase. Details about the mods that were done to it can be found in this thread and described by user 'deadie' whom I bought it from: https://www.head-fi.org/threads/benny-pimped-my-ride.190320/ - I paid around USD$400 at the time, and I have no idea what kind of market value it'd have today.
       
      In addition to the US power adapter, I also have UK adapter, and a UK->Australia converter, so you can use this in quite a number of countries with the additional bits.
       
      I believe I'm asking a very fair price on these, but feel free to reset those expectations if needed. 
       
       
      Photos:
       






    • By dr_carl
      Right now there seems to be a wealth of opportunities in the realm of tube audio here on SNA. Lots of top quality gear at excellent prices.
       
      Or am I  biased, having just gone further down the tube path?
    • By dan-m9
      Item Condition: As New Shipping Options: Pickup available and you can audition.,Shipping is available at agreed cost. Suburb or Town: Toowoomba State: Queensland Payment Method: PayPal (+Fee Cost), Bank Transfer, Cash on Pickup Reason for selling: Changed paths + upgrading Further information:
       
      As new, purchase date 06/05/2020. So plenty of warranty left (invoice supplied). Great decent entry to tubes.
       
      Comes with upgraded matched pair of new 12AU7 tubes (Genalex Gold Lions, RRP $135) they sound much better than the stock ones. Upgraded them as one of the stock 12AU7 tube hisses more than the other one (bad match), happy to include them with the sale if wanted, you could also try to claim warranty on the bad tube as its still so new if you wanted, I didn’t bother as the basic stock tubes are only worth $25-30 new anyway..
       
      Postage would be around $30-$40 due to the weight of this beast!
       
      Thanks.
       
      Photos:
       

       


       

       

       

       

       

       
       




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