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Hi every one  
5 months before    i decided to  hear  vt 25  sound . and I hade (  haltron –teonex –western electric   -Sylvania ). I find one schematic in  single  ended out put with  6sn7 drive .sound was amazing  and balance in all of af band . and  teonex  was very fast in  start and warm up    I want use push pull  circuit for more drive .i think this tube is one of the audiophile choice for music . I need help to find vt25  in  push pull schematic and information for opt  impedance. Thanks   

[JoshK]

The VT-25/10/10y/801/801A/VT-62 (type 10s) family of tubes are said to be really nice.  I am planning to build an 801A preamp (parafeed).  I have been trying to buy them here and there.  They are getting expensive.

A PP amp seem like a cool idea.  I don't know how much power it would produce, likely only 5-8 watts.  Damping will be low, since it has a relatively high rp for an output tube.   Typically I've seen primary loads of 8K-10K for SE type 10 amps.  So PP I'd start looking at 8k-10K plate to plate. 

I'd probably look to the Amity topology or Gary Pimm's Tabor type of topology for the amp and design my own circuit.  I can't recall coming across a type 10 PP amp except a Japanese one that is quite exotic and strange.  I'd think I'd look at circuits for PP 2A3 and adapt them for type 10's instead.  You'll need a bit less swing then 300B's, and likely less than 2A3s too since the type 10's have a mu of 8 instead of 3.5-4. 

Good luck and keep us informed of your progress.

Josh

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Thanks Mr. josh for information's  .
I have just vt25 .please look at the pictures of this two  types . vt25 is  old triode , beautiful and  also  very simple tube   but nice and very musical  sounds . 

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this is my first vt25 single ended amp.

[JoshK]

VT25 is the military designation for 10Y (yours are marked 10y on the glass).  801A is an earlier version of the 10Y, iirc. They are all in the same family of triodes, that was my point.

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Your point was nice  .this tubes  used in old transmitter . and to day  can use in high end  amp . simple –beautiful  and musical  just we can say . and I wish to find 801 . in Iran before  the army used tube for transmitter  but I try to find 801 .

[xecluded]

"I find one schematic in  single  ended out put with  6sn7 drive .sound was amazing  and balance in all of af band "

Would you mind tell me where can i get the schematics for the Single Ended VT25 from.  I'd like to have one built. Thanks.

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Hi

Vt25  need to 10k  opt .and high db speaker .sound  is balance .dht old power  tube with nice simple building . I don?t know why we can not see the parallel  and push pull topology with 10y.
i found   pair of 275-a  it is like vt25.
 

[xecluded]

Do you have schematics. Thanks.

[drummerwill]

 I have a SET amp that I can run many different DHT's power tubes. I have ran 10's, 45's, 50's, 183's, 2A3's, 300B's and SV-811-3's all in this amp.

  Most of these tubes all have sutle differeneces in sound.........except the type 10's.

 The type 10 has a light airy sound with a sharp, solid, quick, bass attack.

  Build an amp with a good solid power supply and use Hi-eff speakers and the type 10 DHT will perform very well musically.

   Good Luck to all in Iran who seek Freedom and Liberty !

    Willie

   

[Scott F.]

Wise words from a master builder

 I have a SET amp that I can run many different DHT's power tubes. I have ran 10's, 45's, 50's, 183's, 2A3's, 300B's and SV-811-3's all in this amp.

  Most of these tubes all have sutle differeneces in sound.........except the type 10's.

 The type 10 has a light airy sound with a sharp, solid, quick, bass attack.

  Build an amp with a good solid power supply and use Hi-eff speakers and the type 10 DHT will perform very well musically.

   Good Luck to all in Iran who seek Freedom and Liberty !

    Willie

   

I looked around my schematics and found this for a VT-62 build. In Iran you may have trouble finding the 76 and 41 tubes. With a bit of modifications to the driver circuit you could adapt it to a more common tube like a 6SN7.

Hey Willie, isn't your 10Y driven by a 6SN7?

[drummerwill]

  Yep! 6SN7 IT coupled for plenty-O drive to DHT outputs.

   A 6SN7 IT coupled to PP 10's would probably just Kill!

     Willie

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Hi
I have 76 in  6 quantity . i  have most of old usa   2 digit tubes .we used this tube  in army  equipments. 
I have another driver like   re134   in dht .

also i have   b65     ecc33   all 6sn7 that has made in usa .
some chorom plate  5751  from mazda   and from 12au7  german .we have all good hifi tube in iran .we dont have  china made tube    never use .iran is different 

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y10 is musically !when we  conect  the 10y to  cd ....