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    VTA ST 70 Which Tubes can be used

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    Pat R.

    Posts : 54
    Join date : 2015-02-26
    Location : SE Pennsylvania

    VTA ST 70 Which Tubes can be used

    Post by Pat R. on Sat Feb 28, 2015 8:50 pm

    OK so I'm new to the VTA ST 70.. can my learned colleagues tell me what tubes can be used in this amp?

    Both in the front end (mini's) and the output tubes. Now I have the Upgraded Tubes that are offered for the kit.. The EH Big Bottles and the 12AU7's (I think)..

    So what tubes can go in the front end and why? I have a surplus of 12bhy for my Cit II and some other similar tubes..

    I see where some have used 6L6's in the Back and even KT 88's..

    I'd love to see comments and such on what tubes you have used and why? and what you feel the results are.

    Bob Latino
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    Location : Massachusetts

    Re: VTA ST 70 Which Tubes can be used

    Post by Bob Latino on Sat Feb 28, 2015 10:03 pm

    Hi Pat,

    In the VTA ST-70 you can use ...

    As output tubes > EL34, 6L6, KT66, KT77, KT88 or 6550 tubes (note - If you have a STOCK ST-70, I do not recommend the last two > KT88 or 6550 output tubes). The best output tubes in the VTA ST-70 (to my ears) were the Gold Lion KT66's. They are a little on the expensive side at about $160 a quad but are well made tubes ..

    As driver tubes > 12AU7, 12BH7, 5963, 5814, 6189 or the Mullard CV4003. Really nice driver tubes are the USA made (RCA, GE or Sylvania) 5963 or 5814 tubes. These are rugged military grade tubes that sound great ...

    Bob

    Pat R.

    Posts : 54
    Join date : 2015-02-26
    Location : SE Pennsylvania

    Re: VTA ST 70 Which Tubes can be used

    Post by Pat R. on Sun Mar 01, 2015 3:33 pm

    After running this amp through the mill since yesterdays completion. I can't see any reason to mess with any other tubes for now.. I'm just going to let my ears get used to it and enjoy it the way it is.. Nice amp..

    I'd still like to hear other opinions on what they like...



    BTW I found a box while cleaning up my shop with some OLD Realistic 5879's in it..

    wildiowa

    Posts : 126
    Join date : 2012-03-19

    Re: VTA ST 70 Which Tubes can be used

    Post by wildiowa on Sun Mar 01, 2015 8:41 pm

    A bit off topic here, but are you currently also using the Cit II? Have you added any mods like the McShane upgrades or otherwise rebuilt it? I am curious how you think the VTA ST-70 compares to the Cit II if you have them both up and running in your system or had a chance to do an A/B comparison.

    Maintarget

    Posts : 209
    Join date : 2013-02-10

    Re: VTA ST 70 Which Tubes can be used

    Post by Maintarget on Sun Mar 01, 2015 8:47 pm

    Pat if this is a new kit build don't waste your time tube rolling until you have at least 200 hours on it specially if you have the Russian cap upgrade it takes at least that long for it to break in and sound consistent be patient it is worth the wait.

    Tube Nube

    Posts : 643
    Join date : 2008-12-06
    Age : 53
    Location : Calgary, AB

    Re: VTA ST 70 Which Tubes can be used

    Post by Tube Nube on Sun Mar 01, 2015 9:16 pm

    I agree that you should definitely logg some serious time in the listening chair. While doing that, I suggest gathering a short list of test tunes for when you do start making comparisons. Songs that are so familiar that you'll remember well hiw the sondstage was, how realistic the tambourine, or cymbals, or piano. I really only use one song for this-- Easy Money by Ricki Lee Jones. It has accoustic bass, cymbally precussion, challenging rhythm, quick dynamic shifts, and subtle vocally stuff.

    Now once you know your amp intimately, you'll probably begin to be naturally curious about the impact of tube rolling, and yes it does make a big impact. Especially if you have those russian commy-tron tubes in there now (Sov Tek, that is). The Gold Lion reproductions Bob mentions are reslly nice. I used the Kt 66's for a while, then following another forum member settled on the Gold Lionkt 88's.

    Bob's post above now has me all eager to try some new driver tubes. I've sourced a few places for GE and Sylvania NOS tubes. Tomorrow I'll pill the trigger, I expect.

    Pat R.

    Posts : 54
    Join date : 2015-02-26
    Location : SE Pennsylvania

    Re: VTA ST 70 Which Tubes can be used

    Post by Pat R. on Sun Mar 01, 2015 9:26 pm

    wildiowa wrote:A bit off topic here, but are you currently also using the Cit II? Have you added any mods like the McShane upgrades or otherwise rebuilt it? I am curious how you think the VTA ST-70 compares to the Cit II if you have them both up and running in your system or had a chance to do an A/B comparison.

    I have a detached building that contains my "listening room" (this is so I don't disturb the rest of the family).. I only heat it enough to keep it above freezing in the deep dark months of winter as the price of oil has been outrageous.

    Now that being said..

    The Citation II has all the McShane Mods.. I can't sing it's praises loud enough.. What an amp. I use a Mc C20 Pre (that I rebuilt last year) out front and a pair of Altec 604C's in original 606 Cabinets with New GPA crossovers


    The sound that comes out of that system is nothing short of magical. The sound stage is there.. listening to a wall of sound mono recording.. there is a wall of sound in front of you. Freq response is fantastic with plenty of nice clean bass..

    Once it warms up a bit I can't wait to try the Cit I with the Cit II, then the Mc with the VTA and the Cit I with the VTA.. I'm going to have a lot of fun with this stuff! Thankfully I keep my audio equipment on a wire shelf with wheels! When I do the shoot out I'll post my feeling here.

    And as to Tube rolling.. I really have never been a tube roller anyway. It's just a matter of different degrees of fantastic anyway.. So I usually set them up and leave them.. this way I can enjoy the recordings more and see what recorded material I can use to bring out the best in the system..

    As to the PIO coupling caps. I have never used them, this is a first.. I have about 20 hours on the VTA now and if in 180 hours more it's going to sound better, I'll really be impressed.


    Last edited by Pat R. on Sun Mar 01, 2015 9:39 pm; edited 1 time in total

    Pat R.

    Posts : 54
    Join date : 2015-02-26
    Location : SE Pennsylvania

    Re: VTA ST 70 Which Tubes can be used

    Post by Pat R. on Sun Mar 01, 2015 9:28 pm

    Here is the Deuce.. Don't ever drop one on your foot. I forgot that this has PIO Caps in it!



    Last edited by Pat R. on Sun Mar 01, 2015 9:34 pm; edited 1 time in total

    Pat R.

    Posts : 54
    Join date : 2015-02-26
    Location : SE Pennsylvania

    Re: VTA ST 70 Which Tubes can be used

    Post by Pat R. on Sun Mar 01, 2015 9:33 pm


    Pat R.

    Posts : 54
    Join date : 2015-02-26
    Location : SE Pennsylvania

    Re: VTA ST 70 Which Tubes can be used

    Post by Pat R. on Sun Mar 01, 2015 9:36 pm

    Prior to the Mc I had a Fisher 400 that I restored.. I honestly think it "colored" the music. It was a nice sound, but colored none the less.. in my opinion.
    The Mc is pure.. I believe the Citation I is also pure. I ended up selling the Fisher (should have kept it.. but then I'm sure we all have those stories)

    Pat R.

    Posts : 54
    Join date : 2015-02-26
    Location : SE Pennsylvania

    Re: VTA ST 70 Which Tubes can be used

    Post by Pat R. on Sun Mar 01, 2015 9:47 pm

    Tube Nube wrote:I agree that you should definitely logg some serious time in the listening chair. While doing that, I suggest gathering a short list of test tunes for when you do start making comparisons. Songs that are so familiar that you'll remember well hiw the sondstage was, how realistic the tambourine, or cymbals, or piano. I really only use one song for this-- Easy Money by Ricki Lee Jones. It has accoustic bass, cymbally precussion, challenging rhythm, quick dynamic shifts, and subtle vocally stuff.

    Now once you know your amp intimately, you'll probably begin to be naturally curious about the impact of tube rolling, and yes it does make a big impact. Especially if you have those russian commy-tron tubes in there now (Sov Tek, that is). The Gold Lion reproductions Bob mentions are reslly nice. I used the Kt 66's for a while, then following another forum member settled on the Gold Lionkt 88's.

    Bob's post above now has me all eager to try some new driver tubes. I've sourced a few places for GE and Sylvania NOS tubes. Tomorrow I'll pill the trigger, I expect.

    I'll look into getting a copy of Ricki

    For testing purposes I have a whole list of LP's and CD's that I use and am very familiar with.

    Lindsey Buckingham - Out of the Cradle (his guitar work sounds superb)

    Nat King Cole - I have a new remastered LP set sounds great

    Elvis - yes, Elvis believe it or not.. some of his recordings are outstanding quality! and so is Patsy Cline.

    Ventures - I have a Mono Ventures LP on Dolphin.. great stuff for the wall of sound imaging.

    Beatles - I have a whole lot of Beatles, but I just bought a new issue mono LP that's outstanding.

    Police - anything by the Police or Sting.

    Johnny Winter - new pressing by Speakers Corner they did a nice nice job on this.

    Then there are just dozens of others.. I listen to on a regular basis.. so I can't wait to try them out! Let's hope for an early spring.

    Tube Nube

    Posts : 643
    Join date : 2008-12-06
    Age : 53
    Location : Calgary, AB

    Re: VTA ST 70 Which Tubes can be used

    Post by Tube Nube on Sun Mar 01, 2015 10:09 pm

    Elvis? Elvis!

    When I was a kid, he was the punch line of a joke: "What's green and sings?" . . . "Elvis Parsely."

    Then he promptly and prematurely died, and only then did I discover him for myself.

    It's a strangely ironic thing -- when someone is so intensely popular that they get promoted to "king", it's easy to over look how great they are. When I hear that voice, it moves me!

    Well you've got a great collection of gear and of music to hear through it. I envy your man cave listening room, Bat Man.

    dougmon

    Posts : 65
    Join date : 2013-11-04
    Age : 60

    Re: VTA ST 70 Which Tubes can be used

    Post by dougmon on Sun Mar 01, 2015 11:30 pm

    Just a note: I put a Siemens E82CC in the middle position of the driver board on my VTA70, and it really opened up the sound. This is after using the supplied tubes for about six months, and they were pretty good as well. I'm going to try an RCA cleartop in the middle position, too, but for the right and left, I think I'll stick with the supplied tubes for as long as possible.

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