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Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Tubes4hifi VTA tube amp and preamp kits and all Dynakitparts.com products


    How many 6550WE's to get as spares and does it matter if matched for ST-120?

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    smoorenc

    Posts : 18
    Join date : 2020-10-29

    How many 6550WE's to get as spares and does it matter if matched for ST-120? Empty How many 6550WE's to get as spares and does it matter if matched for ST-120?

    Post by smoorenc on Tue Dec 22, 2020 10:15 am

    I have a new ST-120 with 6550WE. I love the sound of the 6550WE tubes and the reviews with the ST-120/6550WE's are great too. I wanted to have a spare tube/s on hand just in case there is an issue with one of the installed ones dying. Is one tube enough as a spare? I hear that they will fail one at a time. So for my second and related question. Do I get multiples as spares that are matched? If I change out 1 tube at a time then matched wouldn't matter I guess. Do I need to get 4 matched now and if one of my originals go out, do I replace all 4 with new matched ones?

    Thanks and Happy Holidays!
    Bob Latino
    Bob Latino
    Admin

    Posts : 2976
    Join date : 2008-11-26
    Location : Massachusetts

    How many 6550WE's to get as spares and does it matter if matched for ST-120? Empty Re: How many 6550WE's to get as spares and does it matter if matched for ST-120?

    Post by Bob Latino on Tue Dec 22, 2020 11:19 am

    smoorenc wrote:I have a new ST-120 with 6550WE. I love the sound of the 6550WE tubes and the reviews with the ST-120/6550WE's are great too. I wanted to have a spare tube/s on hand just in case there is an issue with one of the installed ones dying. Is one tube enough as a spare? I hear that they will fail one at a time. So for my second and related question. Do I get multiples as spares that are matched? If I change out 1 tube at a time then matched wouldn't matter I guess. Do I need to get 4 matched now and if one of my originals go out, do I replace all 4 with new matched ones?

    Thanks and Happy Holidays!

    Since the VTA ST-120 amp has separate bias controls, you could mix in one 6550 tube as long as that tube is not weak or has some underlying problem. Another thought if you have one bad or "suspicious" output tube, is to put that tube aside, keep its mate on that channel as a spare and get a new matched PAIR of Sovtek 6550WE tubes for just that channel. Those Sovtek 6550WE's are a real sleeper output tube. They are durable, reasonably priced and sound really good in the VTA ST-120.

    Bob
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    Frank111

    Posts : 105
    Join date : 2015-02-23
    Location : Minneapolis/StPaul Area

    How many 6550WE's to get as spares and does it matter if matched for ST-120? Empty Re: How many 6550WE's to get as spares and does it matter if matched for ST-120?

    Post by Frank111 on Tue Dec 22, 2020 12:32 pm

    I like the idea of having spare tubes. I have a pair of M125 amps, and am still on my original set of KT-120 Tung-Sol tubes. But I recently bought two matched quads of KT-120 tubes to have available to me. Many things can happen that could limit availability. For now, they are priced reasonably, and the availability is good. I plan on buying another set maybe later on in the year and put them away.

    I am also trying to buy NOS 6550 tubes when I can find them. I don't care if they are single tubes or sets as long as they are new. So far, I have several of these in storage. The M125 uses these too.

    Having a supply put away is a good idea. Get them while you have the cash available, and the tubes are in good supply. You never know what can change out there.
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    Dale Stevens

    Posts : 162
    Join date : 2014-07-06
    Age : 71
    Location : Loris, SC

    How many 6550WE's to get as spares and does it matter if matched for ST-120? Empty Re: How many 6550WE's to get as spares and does it matter if matched for ST-120?

    Post by Dale Stevens on Wed Dec 23, 2020 9:05 am

    Yes, S; I keep a complete extra set of matched tubes for my VTA ST120. (KT88 power). That makes it easier for trouble shooting. Also, I get all my tubes from fellow member and tube guru
    Jim McShane. You can find Jim at JimMcShane Designs. Dale

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    How many 6550WE's to get as spares and does it matter if matched for ST-120? Empty Re: How many 6550WE's to get as spares and does it matter if matched for ST-120?

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