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Want to Build more

Ruidoso Bill

Ruidoso Bill

Active Member
Finished my rebuild of a Dynaco Pat5 & ST120. I can't even describe how much enjoyment the project gave me, totally rewarding. I am missing the "Build" aspect, already looking at another project. I have been taking a tube course on youtube and really thinking about a VTA ST70 kit, mostly for the enjoyment of building. I'm 70, ears aren't perfect, my current system is more than I could imagine but want to build more. So, what's best, buy an old ST70 and rebuild or go with the new VTA ST70 kit?
 
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Two great books by Morgan Jones:
Valve Amplifiers
Building Valve Amplifiers

I read them while I tore down and rebuilt an original Dynaco ST-70.

It was like taking a College Level Science course with lab.

Most of what I know came from that experience. I learned a lot.
 
Want to have some real fun? Find a stock Dynaco SCA-35 integrated amp, completely disassemble, and then rebuild with Dave Gillespie's boards. I am in my early 60's and decided to teach myself how to build/repair gear. I started by re-coning and re-capping simple speakers. Then I refreshed a Dynaco ST-70 using Joe Curcio's assembled boards. Then I took the dive to completely rebuild an SCA-35 using Dave's boards and the original SCA-35 construction manual. It was a blast. Dave is on AK and a great resource. The work is not fast but very rewarding. Good luck!
 
Ruidoso Bill said:
Finished my rebuild of a Dynaco Pat5 & ST120. I can't even describe how much enjoyment the project gave me, totally rewarding. I am missing the "Build" aspect, already looking at another project. I have been taking a tube course on youtube and really thinking about a VTA ST70 kit, mostly for the enjoyment of building. I'm 70, ears aren't perfect, my current system is more than I could imagine but want to build more. So, what's best, buy an old ST70 and rebuild or go with the new VTA ST70 kit?
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Just a little word of caution about online "courses" or demos. Some of the guys doing them don't seem to have much experience with tube audio. So, it is best that you get your important information from the well respected books like others have mentioned. Another book that i can point out is the ARRL Handbook. It is filled with basic tube info that is presented in a manner that is less technical and easy to understand. As to which amp to build, if you are fussy about appearances or the cosmetics of an amp then a new kit will be really nice. But, a vintage unit that needs rebuilding can be more of a challenge and probably less costly.
 
Tucker99 said:
I'm almost your age and just venturing into tubes. Where is the tube course you found as that is what I need. I picked up a couple of books but its a bit hard slugging that way.
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YouTube is full of good stuff, us old dog's gotta stick together lol






https://www.youtube.com/watch?v=E71qCufzb38

https://www.youtube.com/watch?v=901iaPVVzY0

http://audiokarma.org/forums/index.php?threads/good-tube-literature.71504/

Lots of good stuff at the top of this forum.

There is much more, get a cup of coffee, log on the fire, laptop in hand and enjoy
 
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petercapo said:
Like a lot of old tube amps, an original Stereo 70 may likely need, at a minimum, selected 1:1 parts refreshing to bring it up to a reasonable level of performance. That is, unless you are fortunate enough to find an original in exceptional condition. But, most originals I see for sale would, IMO, due to sheer age and/or being hacked up over the decades, likely benefit from a complete tear-down, after which all the original parts would need evaluation and possible reconditioning or 1:1 replacement as needed. Then, you'd build it back up and you'd have one terrific amp.

A new kit would be just a build, without the tear-down and parts evaluation/reconditioning/1:1 replacement.

The VTA products are popular and use a different circuit than the original Dynaco, if it matters to you.

Unless you have not yet heard of them, don't overlook the brand new reproductions of the classic Dynaco tube amps offered by dynakitparts.com https://www.dynakitparts.com/product-category/dynakit-products/amplifier-kits/
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Will give them a good look, building is fun and very rewarding.
 
Just a word of encouragement: I've been on the tube road since about 2000 and I still find Morgan Jones' book Valve Amplifiers quite hard going. His 'Building VAs' is easier but there are other easier to follow books out there. I have learned a lot from the Mullard Tube Circuits for Audio Amplifiers, but that is now all available online too. See the articles on this page: http://www.r-type.org/static/contents.htm
 
I usually dig out my Radiotron Designer Handbook 3rd edition, to realize how inept I am at math and how over my head some of this stuff is.
Still, I plug through the book...
 
Tucker99 said:
Yuuuppp...I'm gonna get into them too!
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I am sure that after ingesting some of those "shrooms" you will come up with the best phase inverter circuit ever or a cheap single ended amp that sounds like an Audio Note Gaku-On !
That picture you show with your name gives new meaning to the term "death cap".
 
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