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Partial tear down of Willsenton R8


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On 01/01/2021 at 2:35 AM, TonyAV said:

Purchased the unit with the Psvane KT88 upgrade option

Same as me, got the R8 with the Psvane kt88 option in Oct 20  (did not do any rolling yet). But it takes long time breakgng in.

 

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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

An unexpected development here. Last night, I removed my MELZ 6SL7 tubes and replaced them with the Tung Sol 6C8G. I do not think I will go back to the MELZ.    I can hear the thuds of Stere

It came!!     ??????   Ordered November 22nd.  Arrived January 26th, by ocean.  (I was too cheap to pay the airfreight)    Off we go!  

1 hour ago, Lam Pham said:

Same as me, got the R8 with the Psvane kt88 option in Oct 20  (did not do any rolling yet). But it takes long time breakgng in.

 

It was a long wait for me, but I'm really enjoying this purchase. The KT88 are awesome, I purchased some KT77 to roll, but I'm gonna wait for awhile.

 

Enjoy,

Tony

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10 minutes ago, TonyAV said:

It was a long wait for me, but I'm really enjoying this purchase. The KT88 are awesome, I purchased some KT77 to roll, but I'm gonna wait for awhile.

 

Enjoy,

Tony

Glad that you enjoy, It is harsh at first but smooth out after like a month or more (really).  Let update us on KT77 and what brand of KT77

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3 minutes ago, Lam Pham said:

Glad that you enjoy, It is harsh at first but smooth out after like a month or more (really).  Let update us on KT77 and what brand of KT77

I went with the Genalex Gold Lion KT77 (new production). Had a store coupon, plus the store had a 5% discount deal going on, and I pulled the trigger.

 

Peace,

Tony

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17 minutes ago, Lam Pham said:

Glad that you enjoy, It is harsh at first but smooth out after like a month or more (really).  Let update us on KT77 and what brand of KT77

Interesting. I'll have to let my Psvane KT88 tii burn in. I bought them like 3yr ago, but never used them for more than 20hr because they were so much brighter than my Gold Lion KT88. Unfortunately I only have a pair (because my other pentode amp takes pairs), so no quad for my R8.

 

I actually have a quad of Philips/ECG 6BG6GA on order, with adapters.

 

I also happen to have a quad of CV1079 with adapters I could try in the R8, but I'm hesitant to try them, because they're operating parameters are slightly different than a normal pentode. Maybe somebody with more knowledge can let me know if it's safe to use them in R8, and I'll pop them in and let people know what I think of them in the R8.

 

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On 27/12/2020 at 6:51 AM, Zed Zed said:

 

 

Hi everyone. Experienced in hi-fi but total newbie as far as tube amps go. I am considering the R8 as my first step into this world, for use in my analogue / vinyl setup. I listen mostly to jazz trios and quartets with some big band, acoustic instruments and vocals, especially female. HST, I also like funk such as Quincy Jones, Earth Wind and Fire and so on, with a 'big' sound and a lot of brass. 

 

I am hoping that Triode mode would suit me for the jazz trios, female vocals and so on, and Ultralinear mode for the funk etc. Am I thinking along the right lines?

 

I have what I hope is a simple question: on the China HiFi order page for this amp, there are various options for different tubes.

 

 

2020-12-26_14-24-22.png.e891c16f3fca85ec39d7c77f67218139.png

 

 

2020-12-26_14-24-44.png.005ce74232423f749fa734d1bf811550.png

 

What are the benefits of the Psvane or Shuguang tubes over the less expensive Willsentons?

 

As far as I can tell from the posts here (I read the whole thread, although quickly), most seem to begin with the 'standard' options. Is there any benefit in 'upgrading' to the more expensive options listed? I don't think I will go down the rabbit hole of tube rolling, so I'd like to start as I mean to go on. Any advice gratefully received, so thanks in advance.

 

 

I just ordered my R8 a couple weeks ago and  it should ship any day.  As far as the options  on  the tube's  I went with the PSVANE CV181 COLLECTIONS which also come's with the Wilsenton 6SL7's.

tubes. I decided to keep the KT 88's for now as I already have a quad set of  EL34's.

 

As far as the 6SL7's go I have a matched set of Sylvania VT 229 6SL7 GT'S  {  1944  issue } Kevin's stash from  Upscale Audio. That will be going in,

 

 I originally got these for my Freya plus pre amp,  But after I installed them I got a sporadic  popping noise when turning up the gain on the preamp, there was also a lot of harmonic residence I think it's called when I would touch the preamp or stand, I know the Freya can be a little sensitive to some tubes, I also got a matched set  of  Tung Sol's Kevin's stash for it that work flawlessly , and are a noticeable improvement over the  stock JJ's. 

 

As Thomas & Stereo Reviewed the R8 recently he mentioned running in  triode state and ultra-linear, If I remember right he said he  prefers using the ultra-linear, and also said when using his Freya , that the difference between tri and ultra seemed to meet in the middle , we'll see..

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10 hours ago, Wisker said:

I just ordered my R8 a couple weeks ago and  it should ship any day.  As far as the options  on  the tube's  I went with the PSVANE CV181 COLLECTIONS which also come's with the Wilsenton 6SL7's.

tubes. I decided to keep the KT 88's for now as I already have a quad set of  EL34's.

 

As far as the 6SL7's go I have a matched set of Sylvania VT 229 6SL7 GT'S  {  1944  issue } Kevin's stash from  Upscale Audio. That will be going in,

 

 I originally got these for my Freya plus pre amp,  But after I installed them I got a sporadic  popping noise when turning up the gain on the preamp, there was also a lot of harmonic residence I think it's called when I would touch the preamp or stand, I know the Freya can be a little sensitive to some tubes, I also got a matched set  of  Tung Sol's Kevin's stash for it that work flawlessly , and are a noticeable improvement over the  stock JJ's. 

 

As Thomas & Stereo Reviewed the R8 recently he mentioned running in  triode state and ultra-linear, If I remember right he said he  prefers using the ultra-linear, and also said when using his Freya , that the difference between tri and ultra seemed to meet in the middle , we'll see..

 

I am a total newb when it comes to tube amps, but I have been reading a lot while I am waiting for my R8 to arrive. I am thinking that I may use Triode mode for my female vocals and 'smooth' music and maybe Ultralinear mode for funk-style stuff I listen to. I'll experiment and see if that is how it works out. Good to have the choice. I am hoping my R8 is dispatched soon (ordered late December) and I can find out for myself.

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1 hour ago, Zed Zed said:

 

I am a total newb when it comes to tube amps, but I have been reading a lot while I am waiting for my R8 to arrive. I am thinking that I may use Triode mode for my female vocals and 'smooth' music and maybe Ultralinear mode for funk-style stuff I listen to. I'll experiment and see if that is how it works out. Good to have the choice. I am hoping my R8 is dispatched soon (ordered late December) and I can find out for myself.

Hey Zed, even though I've been into higher end solid state for over 40 years or so I just recently got into tubes. A few of my friend's have always been into tube's With pieces from Cary and Doge to name a few,  and when I hear their systems I like it. Just running my tube preamp with SS is very noticeable.

I am looking forward to trying the two different modes with and without the preamp. I listen to various types of music with  vocals - instrumental slow rock - jazz - blues . My favorite go to is still Floyd and Roger Waters, So I also will be switching back and forth between the two modes to my liking ,  How a person's system sounds to them is what its all about.....

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On 19/11/2020 at 4:33 AM, Atmaj said:

I am using Sylvania 6SL7 GT side gator which has clear top and gray side glass

I am getting a good deal on this pair of Sylvania 6SL7 GT, not sure if these sound like yours? @AtmajThanh lý cặp bóng 6SL7 Mỹ, hàng mới 100%

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19 hours ago, Lam Pham said:

I am getting a good deal on this pair of Sylvania 6SL7 GT, not sure if these sound like yours? @AtmajThanh lý cặp bóng 6SL7 Mỹ, hàng mới 100%

These are silver dome. Mine is side gator. These are supposed to be better than side gator one.

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7 hours ago, Atmaj said:

These are silver dome. Mine is side gator. These are supposed to be better than side gator one.

Thanks Atmaj,

Dummy here, i am learning, Could  you show me how to know it is silver dome or side gator?

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It's a 'gator' as it will thermionically come out at night and bite you. ???

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On 10/01/2021 at 6:11 AM, Comzee said:

I also happen to have a quad of CV1079 with adapters I could try in the R8, but I'm hesitant to try them, because they're operating parameters are slightly different than a normal pentode. Maybe somebody with more knowledge can let me know if it's safe to use them in R8, and I'll pop them in and let people know what I think of them in the R8.

 

I don't think you can use the CV1079 on the R8 as its screen voltage is capped at 300 volts. I suspect the screen voltage on the R8 to be somewhere near its plate (anode) voltage about 500 volts.

 

20210118_225046.jpg

Edited by xlr8or
Attached better image.
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1 hour ago, xlr8or said:

It's a 'gator' as it will thermionically come out at night and bite you. ???

Not sure why, but when I read that I pictured you sitting there with a big box of valves next to you examining one in one hand, and with the other petting a pet Alligator on ya' lap :S

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Since this appears  to be an Wilsenton R8 thread I thought I would post this review hear for those thinking about going to tube amps. I made my decision based on reviews from various sources on a number of amps. This particular article was written by Steve Huff, If your going to purchase an R8 the price will be going up shortly. an explanation of this is written in the details on China hifi .com ...   The below article is a long read and compare's the R8 to several hi end amps. seems like an honest review ...

 

HiFi: The Willsenton R8 Integrated Tube Amplifier is a NO BRAINER BUY. | Steve Huff Photo

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On 11/11/2020 at 4:48 PM, echorec said:

I received the replacement part from Yong yesterday! Instead of sending a potentiometer, he sent me the entire populated bias circuit board with leads attached, so I was quite pleased. I took the amp into my local HiFi shop yesterday and was able to pick it up this morning. Everything sounds good, so hopefully the problem doesn't come up again. I kept the old bias PCB in case I need any of those parts later. The labor cost to replace the bias circuit and bench test was $125 USD, so my R8's cost definitely went up. Still better than having to ship this beast to someone elsewhere and deal with that whole headache. A word of advice: if you have any issues with your amp, be patient with Yong. I think he is absolutely slammed with emails each day. He will get back to you and he will help you make things right, but sometimes he isn't as responsive as many of us are used to. I read somewhere else that he has apparently hired some people to help him, so that is good news if true.

 

A couple of interesting comments from the service guy (This is one of the best guys in our State. He's been building and servicing tube amps for a very long time and works with a lot of high level and boutique HiFi equipment). His first comment was how he thought the design and layout was really good on this amp. He told me the solder job was "a bit sloppy" as he had to touch up several spots inside the amp that could have potentially turned into future problems. His final comment was that he thought the amp sounded "very beautiful and musical".

Hey echorec, After reading through the post's I was wondering if your replaced that tube that was over driven, or if you had it tested during the repair, Still waiting for mine, should ship any day.....

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1 hour ago, Wisker said:

Hey echorec, After reading through the post's I was wondering if your replaced that tube that was over driven, or if you had it tested during the repair, Still waiting for mine, should ship any day.....

 

@Wisker I replaced the tube that red-plated with a new one and kept the old as a backup tube. The old tube sounds fine, but I haven't had it tested it. It was red-plating due to the failure of its bias pot. IMO, the bias pots on the R8 are a major weakness in the amp because they are poor quality. I know of a handful of people that have had failures. It's definitely something to be aware of. Once you set the bias for your tubes, leave them be. Don't tinker with the bias every day and don't worry about small variations on the meter when you test bias as it is completely normal. Adjusting bias once every few months is good. Lee said that the number one reason for failures was people adjusting bias too frequently. This supports my opinion that the pots are poor quality.

 

With the recent R8 changes/updates and price hike, I'm curious to know if Lee also had the bias pots updated to better quality. If someone that gets the updated version of the R8 can take a pic of the bias pots, that would be great.

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2 minutes ago, echorec said:

 

@Wisker I replaced the tube that red-plated with a new one and kept the old as a backup tube. The old tube sounds fine, but I haven't had it tested it. It was red-plating due to the failure of its bias pot. IMO, the bias pots on the R8 are a major weakness in the amp because they are poor quality. I know of a handful of people that have had failures. It's definitely something to be aware of. Once you set the bias for your tubes, leave them be. Don't tinker with the bias every day and don't worry about small variations on the meter when you test bias as it is completely normal. Adjusting bias once every few months is good. Lee said that the number one reason for failures was people adjusting bias too frequently. This supports my opinion that the pots are poor quality.

 

With the recent R8 changes/updates and price hike, I'm curious to know if Lee also had the bias pots updated to better quality. If someone that gets the updated version of the R8 can take a pic of the bias pots, that would be great.

Thanks for the quick feedback, Just thought I'd post a pick of the 6sl7's going in later, I ordered the PSVANE CV-181  Tll collections package but I'm not sure how good the Wilsentons are that come with them, we'll see....

1.jpg

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I'm not sure if this is a generic pic on china's hi fi site but it is on the page where it's noted as upgraded. the board that you posted and a closeup of what they have on there site. After I zoomed in look a little different, mainly the capacitors, your's were brown, the one's in there pic are black, not sure if it means anything, If I remember I will pry the cover off and take a pic when it come's....

222.jpg

3333.jpg

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2 minutes ago, Wisker said:

I'm not sure if this is a generic pic on china's hi fi site but it is on the page where it's noted as upgraded. the board that you posted and a closeup of what they have on there site. After I zoomed in look a little different, mainly the capacitors, your's were brown, the one's in there pic are black, not sure if it means anything, If I remember I will pry the cover off and take a pic when it come's....

 

Another Minnesotan with the R8 amp =O

I'm planning on making a tube rundown myself, I bought 5 pairs of 6sn7, 4 pairs of 6sl7 (and 1 pair 6f8c). I also have the quad 6BG6 coming in.

 

I owned some "holy grail" 6sn7 before I bought this amp, but I didn't want to burn them out running them in the R8. Initial impressions are that the R8 scales well with tubes, but it's not like a pure SE DHT amp, it won't scale to the heavens.

 

PM me if you want to compare notes, maybe we can even do a meetup if you're in the Minneapolis area.

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Guys, first of all my sincere apologies for the delay in posting this review of Miflex Caps. Was going too busy with work with last couple of months.

 

Thanks to @muon* for the suggestion and all his help in the process of replacing the caps. These caps are extremely natural sounding and changed the amp from musical to Audiophile one. If you like natural sound then these caps are must. I played with them a lot, had a good brake in period and pretty happy with it. The sound is not at all fatiguing. I can listen to amp for hours now. It has rolled some of Highs but it is more natural now.

 

After rolling over and having a good amount of brake in period, I tried rolling tubes. I immediately noticed that the amp responds less to tube rolling with these caps (which in fact is a characteristic of a good amplifier). There is less difference in TR and UL mode. Now UL mode is also sounding pleasant to ears where as with stock caps, it was bit harsh.   I changed power tubes from 6CA7 to stock KT88 and they are also sounding good now (previously I did not prefer KT88 over 6CA7 as it was sounding bold). I am still listening to KT88 from last one month and finds it much better than 6CA7.

 

The installation was bit tricky as these caps are quite large in size. I had to add some metal supports in the amp to hold caps as below

 

20201124_180743.thumb.jpg.620c5a5b6f5574351ea74c3d96ab6718.jpg

 

20201124_192425.thumb.jpg.494d02529fe2e4d1efa5f8a0a2143672.jpg

 

 

Installed caps with cable ties on these supports

20201128_160733.thumb.jpg.818069f6eee374cd5d9c1b746d173c71.jpg

20201124_195811.thumb.jpg.4b71187726e6daeb5a122ec0f833621c.jpg

 

20201124_195826.thumb.jpg.afa01efaaf19d52c0c98d969b1dc436b.jpg

 

As per @muon*'s suggestion, installed 390R resistor in series to prevent high frequency isolation on all 4 powertube grids.

20201212_100501.thumb.jpg.40100ef957600d3b9ba0250b998cdf5d.jpg

 

 

My verdict:

 

The stock caps sounds  bit bright and that is exactly why this amp sound more musical than other tube amps. Miflex are very natural sounding and has all the properties of PIOs. It dominates the sound characteristics of the amp and hence less responsive to tube rolling (at least in power amp section).

 

If you really love natural sounding amp, Miflex or other good PIOs is a way to go, else just keep enjoying R8. I love this gear.

 

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I was actually wondering if the issues some folk have been having with power tubes red plating was in fact due to the lack of screen resistors to help with stability in case the screens picking up RF interference. But maybe there are issues with some bias pots *shrug*

 

I'm surprised with these resistors being occluded from the design, but seen them missing in some other Chinese amps even when the supplied schematics show them.

 

Glad you ended up liking the Miflex caps, Atmaj.

Edited by muon*
typo
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37 minutes ago, Atmaj said:

Guys, first of all my sincere apologies for the delay in posting this review of Miflex Caps. Was going too busy with work with last couple of months.

 

Thanks to @muon* for the suggestion and all his help in the process of replacing the caps. These caps are extremely natural sounding and changed the amp from musical to Audiophile one. If you like natural sound then these caps are must. I played with them a lot, had a good brake in period and pretty happy with it. The sound is not at all fatiguing. I can listen to amp for hours now. It has rolled some of Highs but it is more natural now.

 

After rolling over and having a good amount of brake in period, I tried rolling tubes. I immediately noticed that the amp responds less to tube rolling with these caps (which in fact is a characteristic of a good amplifier). There is less difference in TR and UL mode. Now UL mode is also sounding pleasant to ears where as with stock caps, it was bit harsh.   I changed power tubes from 6CA7 to stock KT88 and they are also sounding good now (previously I did not prefer KT88 over 6CA7 as it was sounding bold). I am still listening to KT88 from last one month and finds it much better than 6CA7.

 

The installation was bit tricky as these caps are quite large in size. I had to add some metal supports in the amp to hold caps as below

 

20201124_180743.thumb.jpg.620c5a5b6f5574351ea74c3d96ab6718.jpg

 

20201124_192425.thumb.jpg.494d02529fe2e4d1efa5f8a0a2143672.jpg

 

 

Installed caps with cable ties on these supports

20201128_160733.thumb.jpg.818069f6eee374cd5d9c1b746d173c71.jpg

20201124_195811.thumb.jpg.4b71187726e6daeb5a122ec0f833621c.jpg

 

20201124_195826.thumb.jpg.afa01efaaf19d52c0c98d969b1dc436b.jpg

 

As per @muon*'s suggestion, installed 390R resistor in series to prevent high frequency isolation on all 4 powertube grids.

20201212_100501.thumb.jpg.40100ef957600d3b9ba0250b998cdf5d.jpg

 

 

My verdict:

 

The stock caps sounds  bit bright and that is exactly why this amp sound more musical than other tube amps. Miflex are very natural sounding and has all the properties of PIOs. It dominates the sound characteristics of the amp and hence less responsive to tube rolling (at least in power amp section).

 

If you really love natural sounding amp, Miflex or other good PIOs is a way to go, else just keep enjoying R8. I love this gear.

 

You really aught to try 0.01uf Russian Silver Mica bypass caps across the Miflex KPCU-1. Keeps most of the musicality and tonality of the Miflex while adding this incredible insight into the music and fine detail which makes things sound utterly lifelike. It does so while retaining the naturalness of the Miflex and without a hint of brightness. Just a magical combination  :)

 

https://www.ebay.com/itm/202556601885

Edited by MattyW
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13 minutes ago, muon* said:

"some folk have been having with power tubes red plating"

 

I have a Chinese Doge 10 amplifier, which I really like, but I have two sets of identical 6550 tubes that red plate.  It could be a tube problem, but it could be my mains voltage that is above spec.    Voltage is supposed to be 120 at my house but measures 124 volts.  The amplifier is designed for 115 volts.

 

I have some KT88s that have no problems but the 6550 red plate a bit.  The 6550 sound much more natural to my ear but the red plating is a concern.  

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8 minutes ago, MattyW said:

You really aught to try 0.01uf Russian Silver Mica bypass caps across the Miflex KPCU-1. Keeps most of the musicality and tonality of the Miflex while adding this incredible insight into the music and fine detail which makes things sound utterly lifelike. Just a magical combination  :)

 

https://www.ebay.com/itm/202556601885

Need to try out. but is it 0.01uf or 0.1uf? the link you mentioned is for 0.1uf.

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3 minutes ago, chinook9 said:

 

I have a Chinese Doge 10 amplifier, which I really like, but I have two sets of identical 6550 tubes that red plate.  It could be a tube problem, but it could be my mains voltage that is above spec.    Voltage is supposed to be 120 at my house but measures 124 volts.  The amplifier is designed for 115 volts.

 

I have some KT88s that have no problems but the 6550 red plate a bit.  The 6550 sound much more natural to my ear but the red plating is a concern.  

That's less than 10% so not likely the cause of red plating, what it will cause is a higher heater voltage that will just shorten tube life to some degree.

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You want 0.01uf or 0.02uf. I used 0.02uf.I had no room in my amp for them so used the generally frowned on method of feeding the wires through the bottom grille and sticking to the underside of the amp with double sided tape 

 

These will work too. Will mean they affect more of the frequency range being a larger value. Still small enough not to hurt anything.  Don't get the 0.1uf's though.  My bad on that.

 

https://www.ebay.com/itm/192780198615

Edited by MattyW
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6 minutes ago, Atmaj said:

Need to try out. but is it 0.01uf or 0.1uf? the link you mentioned is for 0.1uf.

Those are sizable and a metal can so I'd be very careful with installation, personally I'd look at physically smaller caps IF you must try by-passes.

 

Personally I usually avoid by-passes across high quality caps.

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26 minutes ago, MattyW said:

You really aught to try 0.01uf Russian Silver Mica bypass caps across the Miflex KPCU-1. Keeps most of the musicality and tonality of the Miflex while adding this incredible insight into the music and fine detail which makes things sound utterly lifelike. It does so while retaining the naturalness of the Miflex and without a hint of brightness. Just a magical combination  :)

 

https://www.ebay.com/itm/202556601885

 

17 minutes ago, Atmaj said:

Need to try out. but is it 0.01uf or 0.1uf? the link you mentioned is for 0.1uf.

 

14 minutes ago, MattyW said:

You want 0.01uf or 0.02uf. I used 0.02uf.I had no room in my amp for them so used the generally frowned on method of feeding the wires through the bottom grille and sticking to the underside of the amp with double sided tape 

 

These will work too. Will mean they affect more of the frequency range being a larger value. Still small enough not to hurt anything.  Don't get the 0.1uf's though.  My bad on that.

 

https://www.ebay.com/itm/192780198615

They are rated at 500v.

 

For the record, I would not use them.

 

 

Edited by muon*
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amazing thread, i just keep reading and learning.  Surley this is the premiere R8 chat on the internet right now!

I am still yet to roll the std Willsenton tubes out, I will wait till they fail me as I dont have the spare funds to do things right now but I did see some great tubes in the classifieds the other week.

 

 

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31 minutes ago, muon* said:

 

 

They are rated at 500v.

 

For the record, I would not use them.

 

 

 

Just slip inside a big tube of heat shrink. She'll be right. Where there's a will, there's a way, and sonic bliss is so close ;)

 

For me it all boils down to whether 500v is sufficient for this circuit..... If not, well..... Kind of rules them out.

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35 minutes ago, muon* said:

 

 

They are rated at 500v.

 

For the record, I would not use them.

 

 

 

I too somewhat agree to @muon*. Also adding 0.01uf silver mica in parallel to PIO would end up like having a stock polypropylene caps.  0.01uf will block low frequencies but will pass mids and highs, 0.22uf PIO will pass on all frequencies and at output of both caps, it will end up with little bit boosted mids and highs.

 

 

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21 minutes ago, Atmaj said:

 

I too somewhat agree to @muon*. Also adding 0.01uf silver mica in parallel to PIO would end up like having a stock polypropylene caps.  0.01uf will block low frequencies but will pass mids and highs, 0.22uf PIO will pass on all frequencies and at output of both caps, it will end up with little bit boosted mids and highs.

 

 

 

Yeah, it sounds nothing like poly caps hey. They bring a transparency and insight that not even Duelund silver bypass caps seem to bring, though they're the next best thing. The only real concern is whether 500v is sufficient in this circuit. Basically its a potential safety issue. Would  need to research this. If 500v is fine then no problem doing it. Basically it depends on the amp.

 

That said, the Duelunds are 600vdc rated..... Might be worth looking at: Duelund JDM Silver Capacitors 600Vdc | Hifi Collective. Either 0.01 or 0.022uf.

Edited by MattyW
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The miflex were not an easy fit as it was, so adding a somewhat large low value caps along side them ?

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Yer, my solution to that is always to insulate them well and mount externally underneath the amp with double sided tape.

 

Anyway, the Duelunds should work. Rated for 600vdc

Edited by MattyW
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3 hours ago, MattyW said:

Yer, my solution to that is always to insulate them well and mount externally underneath the amp with double sided tape.

 

Anyway, the Duelunds should work. Rated for 600vdc

Duelund silver an oil, or tin plated copper foil an oil by-passes would be more suitable, I agree. In voltage and size for better installation, but do cost twice or more what the Miflex base caps were.

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On 04/12/2020 at 11:40 AM, echorec said:

 

Congrats on becoming an R8 enthusiast!

 

The two 6SL7s are the tubes to focus on with the R8, as they will have the biggest impact on sound. The middle tube will have no impact on sound, IMO (I could hear no change). Changing the outer 6SN7s was a VERY subtle for me, but I found myself questioning if I was hearing truly a difference. So, focus on the two 6SL7s and, if you're feeling adventurous, you can try the others. It can be very subjective and system dependent too. In general, the more revealing your system is, the more likely you are to hear the nuances and reap the benefits of different tubes.

 

Down the rabbit hole!

 

Edit: also forgot to say - Listen to your R8 with stocks tubes for several weeks first! There is a break in period with the amp where things smooth out. Then you will have an idea of the R8's "stock" sound.

 

I plan on useing the 6SL7's NOS Sylvania's I picked up some time ago after some running time, But when I ordered this amp I went for the PSVANE CV-181's . for the other 3,  so unless they send the stock tubes with it I wont know how they would of sounded like, Maybe later on I may pick up some TS's to try.....

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