Hey, I've been a member and lurker here for years. I think this is my first post. I just recently had an interesting experience with my 211 based SE triode Wyetech amp and my results were so unexpected that I felt the need to post them. First off I am not a technician just a DIY hobbyist who is not afraid of a soldering iron and multimeters.
Just before Xmas my 211 amps L channel went out
. Fortunately I had the schematic from Roger for the input and output side of the amp. I discovered my plate resistors(for the gain and driver stages) looked a little long in the tooth. Glazed and the board below had heat stains. Fortunately I had the same values on hand in Kiwame 5W carbon films. So I pulled the RCD and RCL wirewound resistors out and replace with the kiwame's. ( I know they won't last as long as the WW but I'll replace every 2 years or so). Needless to say I was surprised at the improvement is SQ. More transparent, better defined layering within the stage. Putting my ear close to the midrange/tweeter area I heard less noise, silence now. Almost like I made a major equipment upgrade not a plate resistor change.
This got me thinking and I started examining the schematic more closely and I found right at the RCA input a 1K ohm Halco H2 resistor connecting to the grid of my gain stage tube (6sn7). I also checked my schematic to my buffered preamp and found a PRP 9372 100 ohm resistor right at the output. I had read for years that bulk metal foil resistors were the closest thing to no resistor at all. So based on my plate resistor swap above I decided to get me 4 Texas components TX2575 bulk foil resistors to replace these already well regarded resistors (Halco, PRP). I reached out to Texas Components and Nelson Bustos replied back to me the same day and set me up with 2- 1K and 2- 100 ohm TX2575 resistors. They arrived in a few days and I soldered the 1K ones into my tube amp at the RCA input to grid of my gain stage tube (6sn7). I spent the next 3 listening sessions focusing on this change. I spend about 1000 hours per year listening to my main system, I know it well. The change made by the TX2575 replacing the Halco H2 had me grinning from ear to ear. It magnified the changes made by the Kiwame resistors. Much more transparency, more layering and separation within the sound stage, leading edges much better defined making dynamic contrasts even more pronounced. Another level of blackness (quiet), music was so involving I couldn't turn it off and I listened past 3 AM each night. I only reluctantly turned it off because I had to be awake the next day. My system that I know so well, had reached new incredible levels I thought impossible. The stage was organic and real.
After the 3 sessions I swapped the PRP resistor in my preamp to the TX 2575. This is right before my RCA output. Although not as dramatic change as the amp swap. what I heard was further enhanced. My stage got both wider (beyond the speakers on most recordings) and deeper. Layering seemed more obvious and the little percussion that many times is hidden in most playbacks was now more evident. I have now gone almost 2 weeks since the TX2575 swap. I just cannot get over the improvement it has made to my system. I rarely turn my stereo off before 3 am now. Music is so involving so real I just want to listen more. What started as a bad moment (L channel went out) has turned into a blessing. Thank you Texas Components and Kiwame. Sorry for the long post, I just had to share.
Just before Xmas my 211 amps L channel went out
. Fortunately I had the schematic from Roger for the input and output side of the amp. I discovered my plate resistors(for the gain and driver stages) looked a little long in the tooth. Glazed and the board below had heat stains. Fortunately I had the same values on hand in Kiwame 5W carbon films. So I pulled the RCD and RCL wirewound resistors out and replace with the kiwame's. ( I know they won't last as long as the WW but I'll replace every 2 years or so). Needless to say I was surprised at the improvement is SQ. More transparent, better defined layering within the stage. Putting my ear close to the midrange/tweeter area I heard less noise, silence now. Almost like I made a major equipment upgrade not a plate resistor change.This got me thinking and I started examining the schematic more closely and I found right at the RCA input a 1K ohm Halco H2 resistor connecting to the grid of my gain stage tube (6sn7). I also checked my schematic to my buffered preamp and found a PRP 9372 100 ohm resistor right at the output. I had read for years that bulk metal foil resistors were the closest thing to no resistor at all. So based on my plate resistor swap above I decided to get me 4 Texas components TX2575 bulk foil resistors to replace these already well regarded resistors (Halco, PRP). I reached out to Texas Components and Nelson Bustos replied back to me the same day and set me up with 2- 1K and 2- 100 ohm TX2575 resistors. They arrived in a few days and I soldered the 1K ones into my tube amp at the RCA input to grid of my gain stage tube (6sn7). I spent the next 3 listening sessions focusing on this change. I spend about 1000 hours per year listening to my main system, I know it well. The change made by the TX2575 replacing the Halco H2 had me grinning from ear to ear. It magnified the changes made by the Kiwame resistors. Much more transparency, more layering and separation within the sound stage, leading edges much better defined making dynamic contrasts even more pronounced. Another level of blackness (quiet), music was so involving I couldn't turn it off and I listened past 3 AM each night. I only reluctantly turned it off because I had to be awake the next day. My system that I know so well, had reached new incredible levels I thought impossible. The stage was organic and real.
After the 3 sessions I swapped the PRP resistor in my preamp to the TX 2575. This is right before my RCA output. Although not as dramatic change as the amp swap. what I heard was further enhanced. My stage got both wider (beyond the speakers on most recordings) and deeper. Layering seemed more obvious and the little percussion that many times is hidden in most playbacks was now more evident. I have now gone almost 2 weeks since the TX2575 swap. I just cannot get over the improvement it has made to my system. I rarely turn my stereo off before 3 am now. Music is so involving so real I just want to listen more. What started as a bad moment (L channel went out) has turned into a blessing. Thank you Texas Components and Kiwame. Sorry for the long post, I just had to share.
It seems Audio electronics is a bit more like cooking than it is mathematics; it's not just the measure of a component in the sauce, it's the component as a specific manufactured element, as an ingredient in the particular recipe. 1 cup flour just inst flour for example, it has its effect on the taste and texture and - I assume - all the different brands and kinds will have their own effect.
And just like in Audio, some clearly taste it and some wont. Extravagance also knows no bounds in the context of what can be done.
Glad to read your "ingredient" change has resulted in such a compelling listen for you! It's one of the things that makes Audio such an intrigue. (Especially when someone says they replaced the powersupply type in their Ethernet LAN switch (from switching to linear) and they hear a difference in their digital music playback. And claim it's repeatable...)
And just like in Audio, some clearly taste it and some wont. Extravagance also knows no bounds in the context of what can be done.
Glad to read your "ingredient" change has resulted in such a compelling listen for you! It's one of the things that makes Audio such an intrigue. (Especially when someone says they replaced the powersupply type in their Ethernet LAN switch (from switching to linear) and they hear a difference in their digital music playback. And claim it's repeatable...)
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Playing with capacitors definitely makes differences and generally when moving to better caps, mostly teflon based in the right locations I have heard very positive changes after the very lengthy break-in. This was my first time playing with resistors tho, one by necessity as my L channel went out and my replacement resistors Kiwame carbon films I had on had and in the right values. I know longevity wise they will not equal the wirewounds I replaced, sonically they are certainly superior. I will look around more to see if I can find other brands that fit there.
The Texas Components are the real surprise here. I was not expecting that dramatic of an improvement. After all the Halco H2 are really good resistors, but in my amp with my digital playback it is audio nirvana. I had a hard time describing what I am hearing so I finally named it Organic perfection. The whole presentation of music is so right so natural. So layered, so transparent, so dynamic. In my 40 years as an audiophile I never had quite this level of personal involvement in my playback space as I do now. My buddy with a $1 million system and custom designed room has a slightly better presentation than I, as well he should for that price. But the differences are much less than they should be.
The Texas Components are the real surprise here. I was not expecting that dramatic of an improvement. After all the Halco H2 are really good resistors, but in my amp with my digital playback it is audio nirvana. I had a hard time describing what I am hearing so I finally named it Organic perfection. The whole presentation of music is so right so natural. So layered, so transparent, so dynamic. In my 40 years as an audiophile I never had quite this level of personal involvement in my playback space as I do now. My buddy with a $1 million system and custom designed room has a slightly better presentation than I, as well he should for that price. But the differences are much less than they should be.
We have completely different understandings of the "fact" concept. Yours appears what is generally known as an "anecdotic fact".
Ok your science only, if it can't be measured it does not exist. That's a fair comment from your point of view. I only reported what my ears tells me and 40 years as an audiophile, who generally follows the dictum "get the science right, then use your ears to tune". The change was truly remarkable, hence the post. You would have agreed too (at least of big sonic difference) if you were here to hear the difference.
"Or are the z-foils just so good they make even Kiwame listenable?"
or were my 15+ year old wirewound plate resistors so bad out of spec that any reasonable replacement would have offered a nice sonic step. (they measured fine out of circuit, but the L channel did go out about 1 hour into a session. 8 weeks later with Kiwame I have had no issues)
The Z-foils, in my application were remarkable. I never expected that.
or were my 15+ year old wirewound plate resistors so bad out of spec that any reasonable replacement would have offered a nice sonic step. (they measured fine out of circuit, but the L channel did go out about 1 hour into a session. 8 weeks later with Kiwame I have had no issues)
The Z-foils, in my application were remarkable. I never expected that.
No, you presented your findings as Texas Components TX2575 bulk foil resistors would always be an improvement over the already very good Kiwame 5W carbon films. As you see, another reputable audiophile of the same breed as yourself just jumped in and disagreed. Maybe he has only 38 years of audiophile experience, so your opinion has more weight?
"No, you presented your findings as Texas Components TX2575 bulk foil resistors would always be an improvement over the already very good Kiwame 5W carbon"
Your confused. The kiwames are plate resistors and the ones I first replaced, because my amp's L channel dropped out. That change was by necessity to get my amp back running and the Kiwame was the only option I had on hand. And yes they improved the sonics and reduced any noise when placing my ear near the tweeter with no music playing. That made me look elsewhere to see what places I could swap resistors to impact sound. The input of my RCA to grid of my voltage gain stage seemed the perfect spot, enter Texas Components. I then swapped the existing Halco H2 input resistor with the TX2575 naked-Z foil resistor. Which just blew me away with the results.
Analog_sa likes the Z-foils and is not a fan of Kiwame's. I replied that I am not married to the kiwame's, its what I had on hand and I liked the results (replacing my 15+ year old wirewound resistors). Then I asked for any suggestions to replace the kiwames that would provide excellent sonics. I will not change the TX2575, those stay. They are also only like .4 W rated, they could never be used as a plate resistor.
Your confused. The kiwames are plate resistors and the ones I first replaced, because my amp's L channel dropped out. That change was by necessity to get my amp back running and the Kiwame was the only option I had on hand. And yes they improved the sonics and reduced any noise when placing my ear near the tweeter with no music playing. That made me look elsewhere to see what places I could swap resistors to impact sound. The input of my RCA to grid of my voltage gain stage seemed the perfect spot, enter Texas Components. I then swapped the existing Halco H2 input resistor with the TX2575 naked-Z foil resistor. Which just blew me away with the results.
Analog_sa likes the Z-foils and is not a fan of Kiwame's. I replied that I am not married to the kiwame's, its what I had on hand and I liked the results (replacing my 15+ year old wirewound resistors). Then I asked for any suggestions to replace the kiwames that would provide excellent sonics. I will not change the TX2575, those stay. They are also only like .4 W rated, they could never be used as a plate resistor.
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I am not 100% sure, this is on the home page; Texas Components is an authorized part of the Vishay Precision Group global supply chain for manufacturing and distributing resistive products made using Bulk Metal® Foil, including standard Vishay Foil Resistors as well as our own unique design applications and derivative products.
and this is on the product PDF; The TX2575 introduced to the market by Texas Components in 2008, is a Z-foil based upgrade of the orginal TX2352(also intorduced by Texas Components in 1997).
So it looks like they are separate but yet integrated, maybe TC makes Vishay Z-foils? I am not sure on that.
Yes, I couldn't agree more. I was astounded by the improvement. Who knew, I never thought changing resistors made much difference. I know better now.
Already made mine: Mills. Excellent at least in respect to Kiwame. Imho only of course.
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