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inherited some stuff.. please enlighten me


MainFrame

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I was recently going through some of my father in law's stuff that my wife and I pulled out of storage and I came across this preamp and three tube amps.  Tube amps are something I've always had interest in but figured I'd never have the spare cash to start up a new hobby.  Now that I've got these amps I really want to get them all fixed up and running.  My father in law was an electrical engineer at Boeing and from what I'm told would go way over the top whenever he would get into a new hobby.

I took all of this stuff to the local vintage stereo shop, but the owner there told me because the two Heathkits are so modified, and the other one is home brew I should fix these up myself at home.  He said they looked to be in good shape and suggested I open them up, clean and inspect everything, pull the tubes and he'll test them for $1 each (but he doesn't have the equipment to test the four Class A tubes).  After that he said I should just throw some speakers on, fire them up and see what happens.  There is one other place in town who said they would test the Class A tubes for $50, but that seems pretty steep to me.

 

 

 

If anyone has the time, would you mind walking me through what I've got here?  From what I've gathered I have two mono amps that have been converted to single-ended Class A tubes, then another homemade two channel amp, also single-ended with two matched 811 output Class A tubes.  The owner of the shop kept saying they were "exotic", but I'm not sure if he just meant it's an unusual way to go about doing things, or if he meant something else by that.  Either way, he didn't want to mess with them.



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wait until you get some advice on here.  Those look recently (last five years) worked on based upon the tubes and caps (I'm no expert my any means).

 

@thebes and many, many others will have some good advice for  you.

 

They will also let you know how to avoid shocking yourselft to death when working on this stuff.  If you don't know what "B+" is I would wait until the real experts dive in here.

 

Travis

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IME, you should expect to pay approximately $600 to have a professional technician restore a stereo tube amp.   You're complaining about paying $50 for someone to do work for you?  How much do you expect a skilled technician to be paid per hour (including their time, and the overhead associated with their test equipment, and shop space) ????

 

 

 

 

 

 

 

 

 

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Welcome to the Forum. You've got  probably a couple of thousands in tube amps there and a classy preamp.  I'm with Travis, those look ot be in tip top shape.  Without puling off the bottoms and snapping some pics, I'm thinking  they have been worked on extensively restored within he last few years.

 

Simplifying a bit, never turn on tube amps that are not connected to a speaker.  Check your local Craigslst and get a pair of speakers and hook them up.  Connect a source, cd player etc., and then fire them up, they should be fine. Or better yet, let the local tech fire them up for you using a variac. Start up order is preamp first, then amps. Shutdown is amps first then preamp. 

 

You have a very valuable gift.  You either spend a few bucks, be awed and enjoy, or sell them to someone else who will actually enjoy them.

 

 

 

 

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22 minutes ago, robert_kc said:

You're complaining about paying $50 for someone to do work for you? 

 

No, he mentioned he could get the output tubes tested for 50 bucks each...which I assume are the big triode tubes tested at 50 bucks each. A bit rich... 

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"There is one other place in town who said they would test the Class A tubes for $50, but that seems pretty steep to me."  

 

That is a total rip off to test tubes.  If he is testing it for specs, output, distortion, etc. that is more than reasonable.  Again, others on here can call you how to much better how to proceed.  

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31 minutes ago, mike stehr said:

 

No, he mentioned he could get the output tubes tested for 50 bucks each...which I assume are the big triode tubes tested at 50 bucks each. A bit rich... 

 

1 hour ago, dwilawyer said:

Those look recently (last five years) worked on based upon the tubes and caps (I'm no expert my any means).
 

..let you know how to avoid shocking yourselft to death when working on this stuff.  If you don't know what "B+" is I would wait until the real experts dive in here.



They have been in storage since he died 18-19 years ago.. although the owner of the shop who looked at them said everything looked all up dated and ready to go.  He also said the caps will discharge themselves withing a few days, couple weeks tops.  I was going to go ahead and test the charge and drain them if there's anything left... I'm unfamiliar with vacuum tubes, but I did take a couple electronics courses in college and done a lot of various electronics repair at home in the past so I should be able to prevent killing myself.. hopefully.


 

58 minutes ago, robert_kc said:

IME, you should expect to pay approximately $600 to have a professional technician restore a stereo tube amp.   You're complaining about paying $50 for someone to do work for you?  How much do you expect a skilled technician to be paid per hour (including their time, and the overhead associated with their test equipment, and shop space) ????



Thing is, money is tight right now.  If we're talking paying someone $600+ to have someone else work on them then I'm afraid they're getting boxed up in the attic for the foreseeable future.


 

45 minutes ago, thebes said:

Welcome to the Forum. You've got  probably a couple of thousands in tube amps there and a classy preamp.  I'm with Travis, those look ot be in tip top shape.  Without puling off the bottoms and snapping some pics, I'm thinking  they have been worked on extensively restored within he last few years.

 

Simplifying a bit, never turn on tube amps that are not connected to a speaker.  Check your local Craigslst and get a pair of speakers and hook them up.  Connect a source, cd player etc., and then fire them up, they should be fine. Or better yet, let the local tech fire them up for you using a variac. Start up order is preamp first, then amps. Shutdown is amps first then preamp. 

 

You have a very valuable gift.  You either spend a few bucks, be awed and enjoy, or sell them to someone else who will actually enjoy them.



I have a few sacrificial speakers kicking around that I was planning on using to test them.. somewhere we should still have my father in law's speakers and turntable that went with this stuff but we haven't gotten to finding those yet.  I already have a variac that I was thinking I would use to slowly bring them up carefully and see what happens when the time comes.

I have no intention of selling any of it.  My father in law died before I was able to meet him and I feel like these amps he built are a way to have a connection with him (other than my wife of course ;) ).
 

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1 hour ago, MainFrame said:

 

 

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The PreAmp is a Dynaco PAS-3. This is still a highly regarded and sought after preamp.

These were put out by Dynaco in Philidelphia in the late 50's early '60s
You can find the schematics on-line along with the manuals usually for free.

 

It has also been used for numerous upgrades and modifications.

Tubes4Hifi makes updated kits and boards for this: http://tubes4hifi.com/

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4 hours ago, MainFrame said:

My father in law was an electrical engineer at Boeing and from what I'm told would go way over the top whenever he would get into a new hobby.

 

You didn't happen to come across any paperwork or schematics for the amplifiers he made?

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3 hours ago, EJC said:

 

The PreAmp is a Dynaco PAS-3. This is still a highly regarded and sought after preamp.

These were put out by Dynaco in Philidelphia in the late 50's early '60s
You can find the schematics on-line along with the manuals usually for free.

 

It has also been used for numerous upgrades and modifications.

Tubes4Hifi makes updated kits and boards for this: http://tubes4hifi.com/

 

 

Thanks!  I'm willing to bet he tore the preamp apart and upgraded a lot of stuff in it too.. I'll post photos when I get a chance to open it up.


 

2 hours ago, Marvel said:

If you mess with the amps with the VT4C tubes, be especially careful. The plate voltage is 750 volts and up. El supremo class A operation.

 

See the attached pdf.

 

Bruce

vt4c.pdf



I'll definitely take that into consideration.  Not trying to blow a hole in my hand (or worse).


 

25 minutes ago, mike stehr said:

 

You didn't happen to come across any paperwork or schematics for the amplifiers he made?



I did not, though I wouldn't be surprised if it's mixed in somewhere.  He wasn't able to pack any of it away himself, otherwise I'm sure everything would still be together.

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Well not sure how you found these and no speakers..lol.  But I would save up the bucks to set them right by a shop and then enjoy. By the way Klipsch speakers sound awesome on tube amps and considering what it would cost you to buy these outright and start from scratch fixing these would be a deal. Plus think how you would stand in your wife's eyes if you got these up and running just for her. I'm not a tube expert but I would say you got some beauties there worth every dollar to fix up.  Pics of the bottoms would help the tube guys here help you out on how to proceed.

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Are you in the Seattle or St. Louis area? If St. Louis, I have a friend who can check these for free.

 

i have two 811 mono blocks; they are quite good with Klipsch. Congrats, your wife probably has a good head on her shoulders with an engineer dad like this.

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On 5/12/2017 at 6:58 PM, robert_kc said:

IME, you should expect to pay approximately $600 to have a professional technician restore a stereo tube amp.   You're complaining about paying $50 for someone to do work for you?  How much do you expect a skilled technician to be paid per hour (including their time, and the overhead associated with their test equipment, and shop space) ????



I totally agree (although I wouldn't really consider plugging a tube in and seeing if it works or not a lot of work).  That's precisely why it makes so much sense for me to do the vast majority of work needed (if any IS needed) myself at home.  A skilled tech will certainly have more experience, but not necessarily more skill, and likely no greater attention to detail.  The main difference I can see is that it will take me a good deal longer to get it all done (depending on said technician's work load.. the guy I took them to week before last said he was backed up for months).  I'm pretty busy myself, so I expect it to take some time to make sure everything is done 100% right.


 

On 5/13/2017 at 2:12 AM, sunburnwilly said:

Nice score , I'm guessing your wife doesn't have any brothers .



How did you know?? lol

 

 

On 5/13/2017 at 2:35 AM, ricktate said:

Well not sure how you found these and no speakers..lol.



My wife said she remembers seeing at least two of the speakers that went with this setup in the storage container, so I've got my fingers crossed.. I feel like I saw the turntable somewhere as well.

 

 

3 hours ago, sheltie dave said:

Are you in the Seattle or St. Louis area? If St. Louis, I have a friend who can check these for free.

 

i have two 811 mono blocks; they are quite good with Klipsch. Congrats, your wife probably has a good head on her shoulders with an engineer dad like this.



Austin, TX..

I talked to a friend of mine in the recording business and he referred me to a guy who specializes in vintage guitars/amps, so hopefully he will be able to check the 811 output tubes.  If not I'll probably end up footing the bill to have them tested at the place that quoted me $50 over the phone.. although I'm not positive that the lady I talked to really knew what I was asking about.  I don't want to end up blowing a transformer or anything in the off chance that one of these tubes is bad.


As far as my wife goes, she is by far the most intelligent level headed woman I have ever known.  Not a day goes by that I don't feel grateful to have her in my life. ;)





I have set myself a goal to have the PAS-3 opened up, photographed, and tubes pulled by the end of the day today, have all the tubes from it tested, and barring any issues have it all back together and fired up by the end of the week.  Then I'm going to move my attention onto the home brew amp with the VT4C tubes.  If all goes as planned hopefully I'll have something hooked up to speakers and making noise within the next two weeks.

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