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    Haven't been around in a while, a few questions

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    Corona

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    Join date : 2010-03-11

    Haven't been around in a while, a few questions

    Post by Corona on Fri Jun 09, 2017 4:59 pm

    Hey all, I haven't been around in a while (was in school and didn't have money for many audio upgrades), but I'm finally getting back into looking at some upgrades for my systems. (VTA-70, M125 monoblocks and SP14 preamp).
    I've been lurking a bit and read about the possibility of using CV181's in the SP14 instead of the sovtek 6sn7's I'm currently running in it. The CV181's are quite expensive for a quad, so this is only something I would want to do if there would be a notable improvement. Anybody else using them in a sp14 or have thoughts on them?
    http://www.ebay.com/itm/4pc-Shuguang-Treasure-CV181-Z-Replace-6SN7-6N8P-Matched-Quad-warranty-12-months-/252433943663?hash=item3ac63c4c6f:g:6e8AAOSwYIhWh2fW

    I've also been seeing those 'hifi' audiophile power cords and was wondering if those have ANY benefit or if they're just pure snake oil. I'm leaning towards them being pure snake oil.

    Thanks
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    deepee99

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    Re: Haven't been around in a while, a few questions

    Post by deepee99 on Fri Jun 09, 2017 7:18 pm

    A good set of high-end Chinese CV-181s will match or top any NOS US-made 6SN7GT. I love 'em. Problem is, their QC is lousy and refunds/replacements, while honoured, are more expensive to return via China Post than to just buy a new tube. I can't personally vouch, but am hearing good reports on the new-issue Tung-Sol 6SN7s. Best source IMHO for those would be Jim McShane.
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    corndog71

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    Re: Haven't been around in a while, a few questions

    Post by corndog71 on Fri Jun 09, 2017 11:54 pm

    If you want to learn some of the science behind power cords consider reading about shunyata cables.  They're a bit pricey but I hear they're very effective.

    Corona

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    Join date : 2010-03-11

    Re: Haven't been around in a while, a few questions

    Post by Corona on Sat Jun 10, 2017 2:01 am

    Thanks for the advice all. I'm interested in the CV-181 tubes, but as pointed out above the shipping to and from China is slightly worrisome. I might just look around a bit to see if there are any US based resellers. I've done some research on the cables and the responses seem to be pretty split between people calling them bogus, and people saying they actually improve sound quality. Makes one wonder if the positive reviews of the cables are a combination of the placebo effect combined with the desire to justify the purchase, or if they really do help.
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    deepee99

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    Re: Haven't been around in a while, a few questions

    Post by deepee99 on Sat Jun 10, 2017 7:57 am

    The Tube Store
    http://www.thetubestore.com/Tubes/6SN7-Tube-Types/Shuguang-Treasure-CV181-Z
    in the U.S. sells the Chinese CV-181 Shu Guang Treasure series with a 3-month warranty, but you're going to pay $220 for a matched pair.

    Dogstar

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    Re: Haven't been around in a while, a few questions

    Post by Dogstar on Sat Jun 10, 2017 8:55 am

    Not trying to start a war but those boutique cables that are astronomically priced are not worth it. Saw and heard a few demos at Axpona and to me its all hocus pocus, mumbo jumbo.

    Another forum member was nice enough to send me a bunch of vintage 6SN7 tubes to try in the center pcb position on my VTA ST-120 and they do sound nice. Just offering that as a possibility rather than springing $400+ for a quad of CV-181's. I'm going to try out the Tung Sol 6SN7 tube also.
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    deepee99

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    Re: Haven't been around in a while, a few questions

    Post by deepee99 on Sat Jun 10, 2017 2:26 pm

    Dogstar wrote:Not trying to start a war but those boutique cables that are astronomically priced are not worth it. Saw and heard a few demos at Axpona and to me its all hocus pocus, mumbo jumbo.

    Another forum member was nice enough to send me a bunch of vintage 6SN7 tubes to try in the center pcb position on my VTA ST-120 and they do sound nice. Just offering that as a possibility rather than springing $400+ for a quad of CV-181's. I'm going to try out the Tung Sol 6SN7 tube also.

    Blue Jeans Cable in Seattle has a great series of articles on the subject of "boutique" cabling:
    http://www.bluejeanscable.com/articles/index.htm
    Strips a lot of the B.S. away from what's really going on with those little electrons our tubes are shooting around.
    Here's also a good primer from BJC on what wire does:
    http://www.bluejeanscable.com/articles/whatwiredoes.htm


    Last edited by deepee99 on Sat Jun 10, 2017 4:54 pm; edited 1 time in total (Reason for editing : Added link)

    Dogstar

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    Re: Haven't been around in a while, a few questions

    Post by Dogstar on Sat Jun 10, 2017 10:17 pm

    deepee99 wrote:
    Dogstar wrote:Not trying to start a war but those boutique cables that are astronomically priced are not worth it. Saw and heard a few demos at Axpona and to me its all hocus pocus, mumbo jumbo.

    Another forum member was nice enough to send me a bunch of vintage 6SN7 tubes to try in the center pcb position on my VTA ST-120 and they do sound nice. Just offering that as a possibility rather than springing $400+ for a quad of CV-181's. I'm going to try out the Tung Sol 6SN7 tube also.

    Blue Jeans Cable in Seattle has a great series of articles on the subject of "boutique" cabling:
    http://www.bluejeanscable.com/articles/index.htm
    Strips a lot of the B.S. away from what's really going on with those little electrons our tubes are shooting around.
    Here's also a good primer from BJC on what wire does:
    http://www.bluejeanscable.com/articles/whatwiredoes.htm

    Blue Jean Cable speaker cables are reasonably priced. I wouldn't consider them to be excessively priced cables. The ones I'm referring to are the ones that are rediculously priced (1000's if dollars) that are simply status symbols with no actual improvement in sound quality compared to BJC's.
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    deepee99

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    Re: Haven't been around in a while, a few questions

    Post by deepee99 on Sun Jun 11, 2017 7:35 am

    Dogstar wrote:
    deepee99 wrote:
    Dogstar wrote:Not trying to start a war but those boutique cables that are astronomically priced are not worth it. Saw and heard a few demos at Axpona and to me its all hocus pocus, mumbo jumbo.

    Another forum member was nice enough to send me a bunch of vintage 6SN7 tubes to try in the center pcb position on my VTA ST-120 and they do sound nice. Just offering that as a possibility rather than springing $400+ for a quad of CV-181's. I'm going to try out the Tung Sol 6SN7 tube also.

    Blue Jeans Cable in Seattle has a great series of articles on the subject of "boutique" cabling:
    http://www.bluejeanscable.com/articles/index.htm
    Strips a lot of the B.S. away from what's really going on with those little electrons our tubes are shooting around.
    Here's also a good primer from BJC on what wire does:
    http://www.bluejeanscable.com/articles/whatwiredoes.htm

    Blue Jean Cable speaker cables are reasonably priced. I wouldn't consider them to be excessively priced cables. The ones I'm referring to are the ones that are rediculously priced (1000's if dollars) that are simply status symbols with no actual improvement in sound quality compared to BJC's.

    Dogstar, you missed my point (or I didn't state it well). BJC's are well-built, high quality, no-frills US-made cables. And they are also very frank about what cable can and can't do. and what it needs and needn't do in the hi-fi (and even broadcast) environment.They put their money into research and production quality, not 4-colour double-track ads in The Absolute Sound. They build to order and if you get your order in early enough (they're on Pacific time) it will generally ship that afternoon or at latest the next day. I am partial to silver-wire interconnects (which they don't build) for some applications, but for most analogue and all digital runs, it's BJC. As an aside, I was in Wal-Mart this weekend and wandered into their electronics section; their Chinese-made HDMI cables were nearly twice the price BJC for a much more substantial, Belden copper-based cable with much sturdier terminations. Bob Latino turned me on to BJC a few years ago and it was damn good advice. Their philosophies seems much the same: all quality and no hype.

    Corona

    Posts : 42
    Join date : 2010-03-11

    Re: Haven't been around in a while, a few questions

    Post by Corona on Sun Jun 11, 2017 5:12 pm

    deepee99 wrote:The Tube Store
    http://www.thetubestore.com/Tubes/6SN7-Tube-Types/Shuguang-Treasure-CV181-Z
    in the U.S. sells the Chinese CV-181 Shu Guang Treasure series with a 3-month warranty, but you're going to pay $220 for a matched pair.
    Hmmm, twice the cost affraid
    I might just need to risk it ordering them from China. Ebay has a pretty favorable policy towards buyers right? If I order them I'll post any updates on the results when they come.

    Dogstar

    Posts : 292
    Join date : 2014-06-23

    Re: Haven't been around in a while, a few questions

    Post by Dogstar on Sun Jun 11, 2017 5:46 pm

    deepee99 wrote:
    Dogstar wrote:
    deepee99 wrote:
    Dogstar wrote:Not trying to start a war but those boutique cables that are astronomically priced are not worth it. Saw and heard a few demos at Axpona and to me its all hocus pocus, mumbo jumbo.

    Another forum member was nice enough to send me a bunch of vintage 6SN7 tubes to try in the center pcb position on my VTA ST-120 and they do sound nice. Just offering that as a possibility rather than springing $400+ for a quad of CV-181's. I'm going to try out the Tung Sol 6SN7 tube also.

    Blue Jeans Cable in Seattle has a great series of articles on the subject of "boutique" cabling:
    http://www.bluejeanscable.com/articles/index.htm
    Strips a lot of the B.S. away from what's really going on with those little electrons our tubes are shooting around.
    Here's also a good primer from BJC on what wire does:
    http://www.bluejeanscable.com/articles/whatwiredoes.htm

    I am using AudioQuest interconnects and speaker cables I made from 12 gage cable I bought from Radio Shack. I do have about 24 feet of AudioQuest Type 4 speaker cable, along with the Termination Pants and some Nakamici Banana Plugs I'm going to put together some say that I hope makes the music sound even more tubey.

    Blue Jean Cable speaker cables are reasonably priced. I wouldn't consider them to be excessively priced cables. The ones I'm referring to are the ones that are rediculously priced (1000's if dollars) that are simply status symbols with no actual improvement in sound quality compared to BJC's.

    Dogstar, you missed my point (or I didn't state it well). BJC's are well-built, high quality, no-frills US-made cables. And they are also very frank about what cable can and can't do. and what it needs and needn't do in the hi-fi (and even broadcast) environment.They put their money into research and production quality, not 4-colour double-track ads in The Absolute Sound. They build to order and if you get your order in early enough (they're on Pacific time) it will generally ship that afternoon or at latest the next day. I am partial to silver-wire interconnects (which they don't build) for some applications, but for most analogue and all digital runs, it's BJC. As an aside, I was in Wal-Mart this weekend and wandered into their electronics section; their Chinese-made HDMI cables were nearly twice the price BJC for a much more substantial, Belden copper-based cable with much sturdier terminations. Bob Latino turned me on to BJC a few years ago and it was damn good advice. Their philosophies seems much the same: all quality and no hype.

    When I wrote 'boutique cables' I was referring to cables such as SilNote Audio cables which don't improve sound quality at all. But look at the prices.

    Corona

    Posts : 42
    Join date : 2010-03-11

    Re: Haven't been around in a while, a few questions

    Post by Corona on Fri Jul 07, 2017 7:13 pm

    Well, I ended up ordering a set of 4 cv181-z tubes from China. I shall provide an update when they arrive and I test them out.
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    deepee99

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    Re: Haven't been around in a while, a few questions

    Post by deepee99 on Fri Jul 07, 2017 7:25 pm

    Corona wrote:Well, I ended up ordering a set of 4 cv181-z tubes from China.  I shall provide an update when they arrive and I test them out.
    I love 'em generally, but QC is hit-and-miss. If you've got a friend with a Hickock, match them as best you can.
    And be prepared for a long wait. China Post takes a month or longer.
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    Kentley

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    Re: Haven't been around in a while, a few questions

    Post by Kentley on Fri Jul 07, 2017 9:14 pm

    N.B. Corona - the leftmost pair of tubes in the SP-14 is the most likely to improve SQ. I run Shuguang CV-181s in those holes and the pretty good TungSol 6SN7s in the rightmost holes (the buffer section) and I swear by it.
    I also have the distinct impression that the Chinese factories are improving their QC constantly. What was true even one year ago is likely to have changed for the better.

    Also note that the CV-181s will, in the standard build, be perilously close to the cage, as they are quite tall. I've circumvented this problem by removing all cage screws save the front center and placing a one-inch shim under the rear of the cage. Again, works like a charm.


    Last edited by Kentley on Fri Jul 07, 2017 10:20 pm; edited 2 times in total (Reason for editing : Additional B.S.)

    eickmewg

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    Re: Haven't been around in a while, a few questions

    Post by eickmewg on Sat Jul 08, 2017 6:48 am

    Corona,
    Good luck with you CV-181 order. The first one I ordered from China was very poorly packed and arrived smashed. I was able to get a rapid refund. I ordered another from a much better-known Chinese source with 1000's of positive ratings. It arrived well-packed and safe and sound. It is in the amplification position of my ST120. I like it much better that the vintage Sylvania 6SN7's I had been using. In contrast, I had terrible luck with new-issue Tung Sol 6SN7 tubes but, admittedly, I didn't get them from Jim McShane.
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    deepee99

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    Re: Haven't been around in a while, a few questions

    Post by deepee99 on Sat Jul 08, 2017 8:44 am

    I've had very good luck with " happydiy998" out of Hong Kong, and a couple of sellers directly from Changsha, which is where the tubes are made, and Shenzen. They're all on FleaBay.
    Don Sachs in Nelson, B.C. keeps a stash on hand and knows some good re-sellers over there but doesn't retail them. He might suggest where to turn, however.
    As Kently mentioned, these Chinese 6SN7s are big, fat, tall tubes; I wouldn't keep -em in the same parts drawer you store your KT-88s in. And as same sage Kentley noted, the two L.H.-side tubes (as viewed from the front panel) are actually the "front" voltage amplifiers -- the SP-13s' and -14s' discrete sections are arrayed in parallel, again left to right as you're looking at the chassis from the control panel -- and the most critical in sound flavour, but don't skimp on the back tubes, either.
    Big as the CV-181s are, they don't seem to generate any more heat than their smaller predecessors, so as long as there is physical room for them you'll be OK.
    I would love to hear a book report from someone who's been using Jim McShane's TS-6SN7s. Jim a:) stands by what he sells, and b:) doesn't sell junk. I just haven't heard them yet and would be interested in hearing from someone who has.



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    arledgsc

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    Re: Haven't been around in a while, a few questions

    Post by arledgsc on Sat Jul 08, 2017 10:28 am

    Psvane has a new UK-6SN7 tube that looks like the bulbous glass CV-181 without all the glass inner coatings and metal wrapped base. It is being offered as a more affordable option. I saw them recently on Amazon and fetch about $100 for a pair.
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    deepee99

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    Re: Haven't been around in a while, a few questions

    Post by deepee99 on Sat Jul 08, 2017 10:46 am

    arledgsc wrote:Psvane has a new UK-6SN7 tube that looks like the bulbous glass CV-181 without all the glass inner coatings and metal wrapped base.  It is being offered as a more affordable option.  I saw them recently on Amazon and fetch about $100 for a pair.  
    Do you have a link?
    Tnx,
    Dave
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    arledgsc

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    Re: Haven't been around in a while, a few questions

    Post by arledgsc on Sat Jul 08, 2017 10:51 am

    Just search "psvane 6sn7" on Amazon all departments and they will pop up.  They are slightly cheaper on Ebay.  At least on Amazon if they are damaged or blown up on first try you can send them back. I have seen them listed as UK-6SN7 and 6SN7-UK if you Google search.

    Corona

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    Re: Haven't been around in a while, a few questions

    Post by Corona on Wed Jul 12, 2017 11:14 pm

    Got the tubes today and after a 3-4 hour break-in period with my cd player on a loop I tested them out playing some music. Whether they're better than the tung sol 6sn7 tubes is to be determined, as I need to try playing a variety of my favorite cd's for analysis and the tubes still need a longer break-in period. They sound pretty good so far, and seem to have a wider range than the 6sn7's with a more 'smooth and effortless' sound to them, but this is all very subjective stuff.

    One negative is the fact that the preamp cage no longer fits over them. They're actually a LOT bigger than the 6sn7 tubes. I guess I can always run the SP-14 with the top cage off and enjoy looking at the pretty tubes Laughing

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    Kentley

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    Re: Haven't been around in a while, a few questions

    Post by Kentley on Wed Jul 12, 2017 11:35 pm

    I have the same situation exactly here. The shim at the rear of the cage does work, and even looks pretty cool. The case is malleable enough so that you needn't fear this solution. I quote myself: "Also note that the CV-181s will, in the standard build, be perilously close to the cage, as they are quite tall. I've circumvented this problem by removing all cage screws save the front center and placing a one-inch shim under the rear of the cage. Again, works like a charm."
    You could probably leave all three screws in the front and do the same. Trust me -- I'm not the Isuzu guy.
    You also could max out your purchase by using two of the CV-181s in the front driver holes of your M-125s. The two innermost holes in the SP-14 are buffers, and a good set of 6SN7s, matched well, will not affect the SQ as much as using the CV-181s as drivers in the power amps. Been there, done it.

    Try these, spread the joy: http://www.ebay.com/itm/1pc-Gold-plated-6SN7-6n8p-CV181-TO-12AU7-ECC82-tube-adapter-6-3V-CMC-ceramic-soc-/191226145817?hash=item2c85f76c19:g:TCYAAOSw7FRWbe7L
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    jfine

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    Re: Haven't been around in a while, a few questions

    Post by jfine on Thu Jul 13, 2017 1:12 am

    Kentley wrote:
    You also could max out your purchase by using two of the CV-181s in the front driver holes of your M-125s.

    Try these, spread the joy: http://www.ebay.com/itm/1pc-Gold-plated-6SN7-6n8p-CV181-TO-12AU7-ECC82-tube-adapter-6-3V-CMC-ceramic-soc-/191226145817?hash=item2c85f76c19:g:TCYAAOSw7FRWbe7L

    So there are no issues doing this?

    "Before this order, please confirm your amp 12au7/ecc82 heat voltage is 6.3v, if your amp heat is 12.6v will destory 6SN7 tube"

    Hey Bob, what do you think about this?


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    Kentley

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    Re: Haven't been around in a while, a few questions

    Post by Kentley on Thu Jul 13, 2017 1:28 am

    This is a non-issue. Both the ST-120 and the M-125 supply 6.3. Many of us have done this surgical procedure. Yes, there is an increase in ampere draw - look it up - but it is not significant when there's only one tube involved - and when one considers the vastly superior power tranny in these units. Trust Kentley. Been doin for a year now, and neatly.
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    arledgsc

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    Re: Haven't been around in a while, a few questions

    Post by arledgsc on Thu Jul 13, 2017 8:05 am

    Corona wrote:Got the tubes today and after a 3-4 hour break-in period with my cd player on a loop I tested them out playing some music. Whether they're better than the tung sol 6sn7 tubes is to be determined, as I need to try playing a variety of my favorite cd's for analysis and the tubes still need a longer break-in period.  They sound pretty good so far, and seem to have a wider range than the 6sn7's with a more 'smooth and effortless' sound to them, but this is all very subjective stuff.

    Nice looking stack of tubes.  The CV-181s take several hundred hours to run in.  I've had new ones sound strange for the first 50 hrs. only to blossom after a few weeks of use.  When you get good ones though they last a long time.

    In the ST-120 I run heavy heater current draw KT-120s and single CV-181.  I've had zero operational issues in three years of doing so.
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    deepee99

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    voltage-amperage issues

    Post by deepee99 on Thu Jul 13, 2017 3:02 pm

    Bob Latino's iron can handle whatever you pretty much throw at it (them). His IE xformers weren't built for wimps, little kids or girls Smile Do I like some of the toroidals out there better? Depends on the application. The Polish make some high-voltage toroidal beauties to order. Weight is not an issue: either comes with the same boat-load of copper. It's just what electricity does. I could start a food-fight here, but to me a well-built IE (not talkin' China here, a least for awhile) and a US/European made toroidal are going to to give you the same results.
    The better builders of these xformers of either flavour are largely mom'n'pop shops and build to order to their suppliers' specs. Pretty much every one is hand-wound.
    From serious wall-wired voltage and amperage measuring over quite a long period, you're looking at, maybe, a 0.2 or 0.3 variation between a boat-load of octals and a boat-load of novals in their respective holes, and I am adding up both pre-amp and amplifier voltage pulls in this measurement.
    As to CV-181 height issues, they've well reported and easily remedied.
    There's no way to evaluate a tube's sonic performance with just a few hours' burn in. 50 for signal tubes and 100 for outputs are my yardsticks, minimum.

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