Suggestions for firing up an old amp for the first time in years...

[Dave Paetow]

Picked up an old tube Dynaco Stereo 70 real cheap, it looks like it is in great shape, just kind of dusty and crusty from storage, but the innards look like new. I'm cleaning off all the dust and crud, almost ready to fire it up.

Should I fire it up without tubes, bringing up the voltage slow with a variac the first time, or ?

It hasn't been used in years.

 

[NewOldCokeDave]

First clean all the dust and crud out inside and out.. Make sure all the caps look good with no leakage out of the ends, or noticeable bubbles on the end.. No burned resistors or wires. Clean all the contacts and sockets with some sort of hi-temp contact cleaner.. I think Caig Dn5 or something like that should be fine. Lord Valve sells a specific hi-temp cleaner as well. Use inexpensive tubes and bring it up slowly on a variac, about 5 volts per minute. (Some people have many different schemes for this, this always works for me) watch for any any signs of stress, heat, smoke, flames, etc..

Happy listening!!

-NOCD

PS.. thanks agin for your help!!

 

[Dave Paetow]

Will do, I'll really clean everything up good tonight and fire it up tomorrow (and cross my fingers!).

Thanks!

 

[sparkletop]

Dave, you probably know this but make sure there is a speaker load (or appropriate resistor) on the outputs. Those output tranny's can be hard to find. Hope it works out.

 

[Dave Paetow]

Yep, I'll remember to hook up the speakers!

 

[NewOldCokeDave]

Actually.. If you blow one, check out www.triodeelectronics.com They got a lot of Dyanco replacement stuff, inculde Magnaquest transformers..

Fyi

-NOCD

 

[Dave Paetow]

I'm going to give 'er the juice as soon as I get back from my bicycle ride this morning,

 

[Dave Paetow]

It's ALIVE! I powered it up slowly as NOCD said, and it works great! I think I'll leave it run for a few hours to let the caps adjust.

 

[Ed Rafalko]

Yay Dave!

 

[Dave Paetow]

Here is a picture of it with the tube cage off:
http://albums.photopoint.com/j/View?u=135458&a=13565183&p=52331613&Sequence=0&res=high

 

[Mojojojo]

VERY cool Dave! Listen, if you ever need parts or advice for it, contact Ned at Triode Electronics in Chicago. They eat, sleep and breath old Dynaco stuff.

http://www.triodeel.com

 

[sparkletop]

Congrats Dave. Thanks NOCD & Mojo... on the tip . I have lots of old radios, a couple of vintage tube recievers and 2 tube stereo power amps. Always looking for "sources". It's great to see people keeping the good stuff going.

 

[Sean]

That looks interesting! (though the output valves look a bit f*cked to me)

Have I ever heard Dynaco amps on a record?

 

[Mike Shaw]

It think the more appropriate question is "have you ever heard an album on a Dynaco".

"Hey you - c'mere" Moe Howard

 

[Dave Paetow]

Sean,
the Dynaco Stereo 70 is sort of the Volkswagen Beetle of tube home audio amplifiers. They made a zillion of them back in the day. Yea, it needs new tubes, one was fried so I stuck a Svetlana in it to get it going.

 

[Mike Shaw]

It think the more appropriate question is "have you ever heard an album on a Dynaco".

"Hey you - c'mere" Moe Howard

 

[Mike Shaw]

Hey Dave,
What are you using as a preamp? I've got a pair of ST70's that I'm going to use in mono and in triode for a living room stereo. I've got an old receiver (transistor) that I can use as a preamp for now, but it ain't got no tubes!!
Mike
"Best of luck to you and yours" Gomer Pyle

 

[Mojojojo]

Preamp

Forgot to mention that Triode Electronics has some very cool hand-wired all tube preamps for the Dynaco amps. I have not heard such warm full tone in a long time...

 

[Mike Shaw]

Really? Where at? I was at the website and couldn't find them.
Mike

"Bang, zoom!" Ralph Kramden

 

[NewOldCokeDave]

Oh s**t, Now you guys have got me thinking of building some tube amps for stereo use.. Damn will this curse NEVER end!!



-NOCD