Dynaco ST 70

marcok

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#1
What do you think about Dynaco ST 70 ?
I 'd like to learn and to do something new .
Does it sound ?
Ciao
Marco
 

Gepetto

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#2
Good amp, low damping factor. Simple design. I had one as a teen, growing up along with the PAS-3 preamp. It was before I discovered how good solid state amplification could be...
 

Skratch

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#4
There are all kinds of upgrades for the vintage Dynaco gear. They still command a good price for an old beater.
 

marcok

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#5
There are all kinds of upgrades for the vintage Dynaco gear. They still command a good price for an old beater.
If I have understood well the critical parts of this design are :
- selenium diode ( replace with silicon )
- 7199 noise ( replace with 12 AU 7 )
- Quad cap ( direct replacement )

Ciao
Marco
 

Skratch

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#6
If I have understood well the critical parts of this design are :
- selenium diode ( replace with silicon )
- 7199 noise ( replace with 12 AU 7 )
- Quad cap ( direct replacement )

Ciao
Marco
You can't replace the 7199 with the 12UA7. The 12AU7 is a dual triode where the 7199 is a triode/pentode.
 

mr_rye89

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#8
Probably a new driver board that uses 12AU7s instead of 7199s. I had one (bone stock except for new caps/diode/output tubes) for a year but sold it after building the WOPL. And adapting 6GH8s to where the 7199s go is a bad idea because I'm trying to hoard all those 6GH8s for my TVs.
 

marcok

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I'm very curious about any tech item
#9
Probably a new driver board that uses 12AU7s instead of 7199s. I had one (bone stock except for new caps/diode/output tubes) for a year but sold it after building the WOPL. And adapting 6GH8s to where the 7199s go is a bad idea because I'm trying to hoard all those 6GH8s for my TVs.
Thank you guys ! I have to study again ! 6G8HA. should be a good equivalent.
Ciao
Marco
 
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