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    ST-70 With VTA Driver Board - Medium Budget Tube Upgrade Suggestion Request

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    aguaazul

    Posts : 45
    Join date : 2012-07-08
    Location : Livermore, CA

    ST-70 With VTA Driver Board - Medium Budget Tube Upgrade Suggestion Request

    Post by aguaazul on Tue Aug 18, 2015 5:36 am

    I have a ST-70 With VTA Driver Board. As I look through the suggestions on upgrading the 3 EH-12AU7 Tubes I received with the board ($40 for all 3, very reasonable) I'm thinking about picking up some different tubes to roll in there.

    I don't want to start out with high $90 per tube upgrades. So I'm asking if there are suggestions for upgrades that won't break the bank.

    I run the VTA TCLA Line Stage w/ ZMOD Phono Stage, the ST-70 runs just the Mid-Range Driver and 8 Tweeter array on a pair of Bi-Amped Bozak Symphony Speakers with the ceramic magnet drivers rating them at 91 db in the sensitivity area. The woofers are run on a SS High Damping Factor Carver A-220 amp.

    Are there some tubes that I can play with in the 25 > 40 dollar range that I may enjoy trying?

    Let me know, thanks,

    Blue


    Last edited by aguaazul on Tue Aug 18, 2015 11:29 am; edited 1 time in total (Reason for editing : Error in the word Damping - oops.)

    corndog71

    Posts : 454
    Join date : 2013-03-19
    Location : It can get windy here

    Re: ST-70 With VTA Driver Board - Medium Budget Tube Upgrade Suggestion Request

    Post by corndog71 on Tue Aug 18, 2015 11:08 am

    I recommend tubes from RAM Labs. Roger knows how to pick the winners. Make sure to request "matched for gain" and use it in the center socket.

    http://www.tubeaudiostore.com/12au7stangra.html

    sKiZo

    Posts : 1312
    Join date : 2013-04-01
    Location : Michigan USA

    Re: ST-70 With VTA Driver Board - Medium Budget Tube Upgrade Suggestion Request

    Post by sKiZo on Tue Aug 18, 2015 12:03 pm

    You didn't mention what you feel is lacking with the EH tubes? If you're looking for brighter, the RCA clear tops definitely fit the bill and you can find those for around $10 a pop if you shop around. Used 12BH7's or 5814's are also inexpensive options and will usually give you a darker sound ... more bass and less top that works quite well with most genres ...

    Heck, for the money you quoted, get a set of each, and buy yourself a pizza to celebrate. clown

    Bob Latino
    Admin

    Posts : 2414
    Join date : 2008-11-26
    Location : Massachusetts

    Re: ST-70 With VTA Driver Board - Medium Budget Tube Upgrade Suggestion Request

    Post by Bob Latino on Tue Aug 18, 2015 12:16 pm

    Check out some of the older USA made military/industrial 12AU7 type tubes as sKiZo has mentioned. There are still plenty of these floating around .. These include the 5814, 5963 and 6189. In general these USA made RCA, Sylvania or GE tubes are better made than the modern Russian, Chinese or Slovak (JJ) tubes. There is no guarantee that they will SOUND better than the newer production tubes but they almost always last longer than their modern counterparts. Another nice 12AU7 type driver tube is the older British made Mullard CV4003. Presently I use a Mullard CV4003 as the front (voltage amplifier) position of my M-125's and a GE 12BH7A in the rear (phase splitter/inverter) position.

    Bob

    aguaazul

    Posts : 45
    Join date : 2012-07-08
    Location : Livermore, CA

    Re: ST-70 With VTA Driver Board - Medium Budget Tube Upgrade Suggestion Request

    Post by aguaazul on Wed Aug 19, 2015 12:16 am

    Thanks for the suggestions!  Since I dropped in the VTA board all I've listened to are the EH's. This amp is currently only used for Mids & Highs, no need to go darker. I think I'll start changing the middle tube with a RAM Labs 12au7, seems like a reasonable quality tube.  Then start looking for a vintage Mullard CV4003 (those look pricey)  & RCA Clear Tops (they seem reasonable).  

    I'm currently in testing mode of the Lampucera1.0 & Lampizator DAC Kit i built. After it's set up & dialed in I'm looking at tube rolling.
    I can do the A - B - C listening tests with this DAC. But that is for another thread.

    Having tons of fun!


    Last edited by aguaazul on Wed Aug 19, 2015 12:18 am; edited 1 time in total (Reason for editing : Deleted double word.)

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