The Music Man Returns-Amp tech advise

I recently pulled my family's long lost MM HD 212 130 out of a lawnmower shed (everyone always wondered what happened to it). My Father had bought it around 74 and I was given the amp sometime in the late 80's, but at 12 years old decided that I would never be able to get the guitar to stop making this horrible buzzing noise when I strumed it, (unfortunately nobody ever explained guitar setups and fret buzz, ect.) and so the MM amp ended up like that sock that just disappears in the dryer.
20 years later, the amp shows up 400 miles from where I last saw it at my father house, in a tool shed near Death Valley. (He always swore I had it!)
I would post a picture of the amp in the dusty condition it was in when I pulled it out (think Raiders of the Lost Ark), but I'm not one for public humiliation.
Cleaned the amp with compressed air, pluged it in, turned it on and immediately stuck both of my index fingers in my ears and squited my eyes for about 15 seconds...nothing...plugged in my guitar and behold "the sweetest clean tone I could ever imagine"...
Now for some questions:
1. I know I need to take it to a tech and it probably needs a cap job and some of the pots cleaned, but I've never been to an amp tech before...I live in LA and know its not cheap, but is there any scams I should watch out for and how should I watch out for them? I'm generally a trusting person, but times are tough and everyone is looking to make some extra cash. Is there anyway to check the work, make sure parts have actually been replaced or aren't missing. Is it okay to ask for the old caps, or is this very insulting? Just looking for some amp tech ettiqutte. Should I inventory the tubes before I take it in?
2. What ohm should the speakers be set to 4 or 8? They are the original 12" with the MM stickers on the back...friggin HEAVY...I'm not so familar with wiring, so I don't know how to tell if the in a series or parallel and I am not sure what ohm the speakers are...Does anybody know?
your advise is much appricated...
SB

George these amps are built like tanks!My advice if it's not broke don't fix it .just clean it up and play the tar out of it.If there are any probs they will show up eventually and you can look into fixing them then.There have been many on here found Musicman amps in worse shape and found them to sound great.just a thought.

So is it complete bull that caps should be changed out about every 10 years...? Especially ones that have sat? I have always been of the school that it is better to spend now than later and I was under the impression that replacing caps now would be a lot cheaper than having to possibly replace transformers later. I am so happy to have found the amp and the truth is that I realize that they do not make things like they use...actually it seem like we hardly make anything nowadays! I didn't realize the value of this amp when I first had (I don't mean $ wise.) So this is what I mean by scam...are cap jobs a scam?
Any idea about the ohm setting...8 or 4? thanks so much!

I never meant that having a cap job was ever a scam,all I was saying is you said the amp sounded great, usually if it needs caps or other fixes you will notice quickly,it will sound either weak,noisy,or just really bad.If you have the extra cash ,its a great idea to do some preventative measures.there is a whole debate on here about ohm settings ,you really only change that with a extension cab,but you could have to if you change to a differnt ohm speakers..ect.

I see your point...if the caps are bad or worn I would be able to hear it, which means that I can probably play it without the fear that it will blow up. I did get the most beautiful tone out of it, but truth be told I never cranked it because it thought it was going to start a fire or something, so maybe I should give it a real run around the track and see.
When I cleaned the amp I might have changed the ohm setting by accident and now I can't remember what it was, which is why I was asking which one is correct. I believe that the factory setting with the two stock combo speaker would be at 4ohms and then you could switch to 8ohms if you added an extension cab...Does that sound right?

yes i believe you want it in in the 8 ohm setting,add a cab change it to the 4ohm setting.

That amp is now 35 yrs old. I Would suggest getting it re-capped if it has not been done before. Especially since it sat for so long. They DO dry out and when they go bad, they take expensive stuff out with it. Caps are cheap compared to a transformer. Mike.

George, since you are new to these amps and probably have not yet read everything on this site there is one tip that I think is really worthwhile. A lot of heat builds up in the chassis above the power tubes. Not enough to fry an egg on the top of the amp but close. I've experienced two near melt downs with my 410 HD130 in hot stagnant practice rooms so I bought a cheap clip on fan and it keeps the tubes in check and top of the amp as cool as an unrefrigerated cucumber. I couldn't give you proof or a detailed explanation of why this helps but the amp now runs cool and hasn't acted up since.

I was thinking I was gonna go ahead and have it re-capped and just generally gone over. The money isn't a problem, but I have never been to an amp tech before and was just wondering if there are things to watch out for. Since there isn't any significant problems this would just be preventative, so it would difficult to tell if the work had actually been done and correctly. I wasn't really worried about it and then a friend said something about techs stealing old vintage tubes. I'm a very generally trusting and don't want to come off like a jerk, but if my experiences with a few car mechanics is any indicator of the capacity for someone to take you to the cleaners, then I want to make sure I know what to look for. Like I said, I don't mind paying for GOOD and HONEST work, but they say that if you can't spot the sucker in the room, then it's probably you and in this case I just don't want to be the sucker.

Thanks for the tip Chris!
I haven't really ran the amp on HIGH yet and it seems to only get a little warm on low.
Do you think I could cover a fan in tolex to keep the look?

That's good. Just file it away in the back of your mind in case you ever have any heat issues. Except for a little bit of the clip my fan is hidden in the back.
As far as amp repair I wouldn't worry about it too much. It's not like you drive down Main street and have to pick which old tube amp repair facility to give your business to. Word of mouth works best. Talk to other players that have had good experiences and follow their lead. My feeling is that most of the people repairing tube amps in their shop or basement enjoy doing it and aren't looking to scam anyone. Some are more talented than others but you should be able to sort that out through recommendations.

It's the 4 ohm setting. MM used 8 ohm drivers. A 2x12 combo is 2 x 8 ohms wired in parallel = 4 ohms. If you add (for example) the 2 x 12 RH cabinet which is also 4 ohms, you set the switch to 8 ohms as the two jacks are wired in series.
Sincerely
Lars Verholtwww.captain-foldback.com

4 ohm...I figured it out...Thank you! I couldn't get my mind around the whole series vs. parallel thing, I understood it on paper, but when I looked at the wires I kept thinking that they where in series, because I thought if they were in parallel the wires would split (like in many diagrams), but they actually meet at the terminal. It thought "that's funny into one, out to the other must be series" and I couldn't figure out how the amp could support two 8 ohm speakers with only 4 ohm and 8 ohm settings, because that would require 16 ohm...correct?

The amp's internal speakers are wired in parallel, like Lars said (i.e. 4 ohms from two 8 ohm speakers), but the extension jack is wired in series, so you ADD the external cab's impedance to the internal impedance (e.g. a separate 4 ohm cab would make the total 8 ohms). Note that this is different from most amps where the extension jack is wired in parallel, meaning that adding external cabs lowers the overall impedance.

Hi George,
Not to long ago I was lucky enough to have Ed Goforth go through my 2/12/65 Music Man amp. Ed gave me different options on what caps/tubes I could buy, and I did go with the high end ones.
Anyway.. New caps/tubes/set bias/cleaning + labor, came to around $250.00.
Ed also gave me back my old caps and tubes (He said my old tubes were still pretty good and I should hang on to them.)
That's my tech experence and I feel very fortunate to know Ed.
Good luck, hope it works out well for you.