Replacing tubes AC15C1: reality vs myths: HELP???

Discussion in 'Amp Central Station' started by superbadj, Jul 30, 2013.

  1. jefrs

    jefrs Doctor of Teleocity

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    You are left pond, I don't know why but we don't see much of New Sensor's Gold Lion and new Mullard over here. I am not seeing any of my favourite low-gain low-current EL84 there either, not Brimar/Mazda types, only Telefunken and Mullard copies in the main. They all really need gain and anode current test values shown.
    I go here http://www.watfordvalves.com/home.asp


    I do not have many NOS and then only cheap ones, what I do have are a few old real ones.

    And no, I have never found that NOS last any longer than good new ones. Nor for that matter do they sound much better e.g. I found new Svetlana =C= to be significantly better 6L6GC than NOS GE-JAN
     
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  2. Kilofunk

    Kilofunk TDPRI Member

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    Just retubed my Laney GC30V, JJ gold ecc803s for V1, TAD 7025wa for V2 and PI, and 4 TAD el84-STR, worked out real well... sounds great. Good luck
     
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  3. jefrs

    jefrs Doctor of Teleocity

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    Fyi -
    the JJ-ECC803S is a long plate and "warm sounding" but it is not the copy of the Telefunken ECC803S. It is the JJ-ECC83S that is the low-noise low-microphonic semi-copy of the Telefunken ECC803S (high-gain low-noise V1 job ;)

    The TAD ECC83/7025WA can either be the RT080 copy of the low-noise Sovtek 12AX7WC/7025-STR or the possibly higher gain RT008 aimed at Fender amps.

    The TAD EL84C-STR is probably Chinese, but is found OEM in many Laney amps. The OEM in my L5T were mostly Chinese TAD, probably best to just say that they didn't last long. Some TAD are Chinese (GT too), others not, it's hard to tell from their descriptions.
     
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  4. Coldacre

    Coldacre Tele-Meister

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    and that's kinda the problem; you've decided that the amp isn't worth investing in a great set of tubes for it. you'll never hear what it's capable of (nor get great mileage of the power tubes).

    e.g.

    V1 - ANOS Mullard $75
    V2 - ANOS Sylvania $32

    2 X NOS Tesla EL84's $75

    $182 - your AC15 is sounding top notch, with power tubes that withstand 12 months of live work.
     
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  5. Unadan

    Unadan Tele-Holic

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    Thinking I might try and track down a NOS RCA 12AX7 and put it in the V1 position of my AC15C1. I'm leaving the other tubes stock until they need to be replaced.

     
  6. MadJack

    MadJack Friend of Leo's Silver Supporter

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    I know, old thread!

    Anyways, I started as a fan of the current production Tung-Sol 12AX7, till I tried the new Mullard CV4004/12AX7 (short plate).
    To me, it has the most vintage sounds of any of the current production tubes I've tried. Very warm mids, smooth, rounded highs and nice low end. With the AlNiCo Blue Dog it sounds great. It may be too much for a Greenback, I don't know, I haven't tried it with them yet.
     
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  7. Silverface

    Silverface Poster Extraordinaire Platinum Supporter

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    With more experience you will likely be able to pick up on the nuances of things you currently don't recognize. There have been plenty of articles over decades demonstrating players recognizing the differences. The string doesn't HAVE to touch the fretboard - it's touching a fret firmly attached to the fretboard, and the board makes a difference - the woods vibrate differently just as do different tone woods, bridges, and headstocks loaded with heavy vs light tuners.

    But the differences ARE subtle.

    Re tubes - read as many reviews as you can. Asking on a forum is probably the way to get the most biased, subjective view you can. I have a personal opinion based on years of comparison in actual Vox amplifiers; others may have the same, or may have one amp they have experience with, or have never used a Vox in their life. Or a tube amp.

    Anyway - personally, I like JJ's power tubes, but I don't usually care for their preamp tubes except in certain amps. Vox amps are not among them, and I don't particularly like JJ EL84's. NOS EL84's are not very expensive compared to other power tubes and they are plentiful. Vox amps work the tubes VERY hard and hot - you need rugged, good sounding tubes...and modern EL84's are not, IMO, the equal of NOS tubes.

    As far as preamp tubes - NOS exclusively in a Vox. No exception. Both for durability and tonal reasons, I would stick with GE, RCA, Sylvania, Philips, Mullard, or Amperex. They will last you for years if you keep the amp serviced. JJ's sound weak to me, and European & Asian tubes don't have the sound OR durability for a Vox amp.
     
  8. Unadan

    Unadan Tele-Holic

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    Yes the thread is old. But still cutting edge relevant as this amp is still in production. How would you compare the new Mullard to an NOS RCA 12ax7?

     
  9. Marc Morfei

    Marc Morfei Tele-Afflicted

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    I am reviving this thread since I have an AC15 and am facing this same issue about tubes. This topic shows up all the time, but I am confused. I have read many threads that have offhand comments like “of course swap out the V1 tube...” 1) why?, 2) with what?
    So is there common wisdom on tube upgrades for an AC15?
     
  10. Mike Eskimo

    Mike Eskimo Telefied Ad Free Member

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    6P14P -EV
     
  11. Mike Eskimo

    Mike Eskimo Telefied Ad Free Member

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    upload_2019-1-16_19-41-23.jpeg
     
  12. MadJack

    MadJack Friend of Leo's Silver Supporter

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    V1 is the first valve in the sound chain. It has the greatest effect on the sound and gain of the amp. The other tubes support that valve.

    Some like the Tung-Sol 12AX7, it's a bright and lively tube with strong gain. Some like the JJ ECC83, as it's a balance response tube. I currently run a Mullard (RI) CV4004, it's a slightly warmer tone, with a bit of smoothness. I'm thinking of going back to the Tung-Sol, as I like the crunchy rock tones and drive.

    The 6P14P -EV that Mike Eskimo listed are power tubes. Russian replacements for the EL84s. I have them in mine.
     
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  13. Marc Morfei

    Marc Morfei Tele-Afflicted

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    Thank you!
     
  14. Andy B

    Andy B Friend of Leo's Silver Supporter

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    Both the Tung Sol RI and the Mullard CV4004 RI are excellent V1 tubes. The other Mullard RI ECC83 which is a long plate version is also excellent if you want a darker sound.
     
  15. superbadj

    superbadj Poster Extraordinaire

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    Well, no. I stopped shopping for amps when I got this one because it's perfect. So I haven't decided it's not worth investing in. I meant that I (a) don't have unlimited funds, and (b) don't buy into the cork sniffer approach to everything (see below).

    With more experience, I'll "pick up" on things I currently don't recognize. Really? How much experience do you think I have (or don't have)? How do you know? How long have I been playing guitar and writing music?

    Come on, man. That's a gigantic assumption, and one based in absolutely nothing other than I call BS on so much of that junk. And to be clear, I'm not saying there are no differences. I'm saying there are no practical differences. No useful, meaningful, consistent differences that anyone cares about.

    Hell, the humidity of the air will affect how your guitar and its strings resonate. Do you only play when it's 47-49% humidity, lest your tone suffer? Of course not. But there is a difference, detectible by lab equipment. It's there. We don't have to rehash this dead horse, but in a live setting, or in a full band recording, or if someone is listening in a car....there isn't an ear alive that can consistently tell you if the guitar in a song features an ebony, rosewood, or maple fretboard, or .11 or .12 strings, or nitro or poly finish, or freaking heavy tuners vs light weight ones. Nobody can even consistently name what guitar is being used without prior knowledge of what the artist uses, much less the ultra-subtle differences that exist between alder and maple. And obviously this is ignoring the fact that all of these differences compound each other when added together, muddying the final result (is it the body wood, finish, or fretboard that's making the guitar sound "snappier"?). And...nevermind the logic that rosewood on a fretboard is warmer, softer sounding than maple...but a full rosewood guitar (harrison tele) is harsher, thinner, spikier.

    I appreciate the info on tubes, I really do. But don't approach questions like this with an "Awww little fella, one day you'll grow up and have an ear that can appreciate the finer points of tubes." It's condescending, and you can do better than that.
     
  16. Silverface

    Silverface Poster Extraordinaire Platinum Supporter

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    Well, you probably know more now than you did when you started this thread 6 years ago. But you seem to have the same attitude. So I would venture to guess not all that much more.

    Nothing was condescending - YOU were the one that said you didn't know anything about tubes, and claimed there were no differences in tone between certain types of guitar construction that have been long established as real.

    But "no useful, meaningful, differences ANYONE (caps are mine) cares about"?

    I suggest you do a LOT more study/reading - or don't ask questions involving any of these subjects. Because IMO You still have a LOT more to learn. That's not condescending - it's an opinion based on 50 years of technical experience.

    You claim limited experience, diss technical details as "cork sniffer" BS - so why do you ask questions at all? You apparently only want answers you already believe. Seems like a waste of time asking, unless the purpose is trolling.
     
    Last edited: May 13, 2019
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  17. AJBaker

    AJBaker Friend of Leo's

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    JJs seem to work fine...
     
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