ebay Madness

[bob p]

its hard to believe what some people will pay for untested old PA amps on ebay. can anyone explain why this old Masco went for over $200? I've got to be missing something...

Vintage Masco Model ME-27 Tube Stereo Amplifier-Working - eBay (item 140415535160 end time Jun-17-10 08:24:22 PDT)

[Bill Moore]

Isn't it the "one man's treasure" idea?
My amp tech friend had to move, and was cleaning out under his bench, listing on the bay. Had some european tube reciever that was too expensive to fix, ended up getting over $300 untested!

[J M Fahey]

can anyone explain why this old Masco went for over $200? I've got to be missing something...

Can hardly miss them !!!!!!!!!!
I'm speaking about the "magic" words "vintage" and "tube" used on the main description.
Add to it the *obvious* "vintage tube amp" styling plus the internal photos showing the spaghetti plate type ... excuse me, vintage PTP wiring, and those $200 look cheap indeed.

[Sweetfinger]

It's the new thing......all the cool kids are doing it. You buy an old lunchbox pa head and have it converted to a guitar or harp amp. Next, wearing an onion on your belt will come back into style!

[bob p]

I understand the visual appeal of a funky old metal box PA amp, but that rats nest of 50 year old dried out caps and crumbling wires is a nightmare. Having worked on a few of those amps, I know enough to pay nothing more than salvage value for the box and the iron.

When you open them up its always a disaster inside. The cloth insulation on the wires is always overheated and crumbling. The wires are so discolored from the heat that the striped color codes aren't even legible, and it seems that you're always trying to read the color code on a wire as it disappears into a wad of spaghetti that's balled up around a tube socket where everything has been blackened. The ball of spaghetti is wadded up in such a tight knot that it's impossible to replace a single component -- if one part fails you're stuck with removing every part in that gain stage (as well as the gain stage before and after it sometimes) just to get to the part that you want to remove. And then there's always that raised ground bus that's conveniently located right over all of the wiring that you need to work on. If the amp even runs its got dried out caps and the circuit is always full of hum and noise. The last one of those I worked on was so bad that the signal to noise ratio was reciprocal! Instead of a tiny noise artifact riding on my test signal, I had a tiny little signal riding on a giant noise wave!

Yes, those boxen are nice to look at, and they definitely have "retro" appeal. But if you want one to be reliable enough to sound good, sand safe enough not to kill you, then you'll have to gut the chassis and rebuild it from scratch. I think those kids that are buying these amps because they look kewl really don't know what they're getting into.

On a positive note, the octal preamps in all of those amps are a nice change of pace. Gutting the box and building a tweed pro circuit around that old iron would be a nice project, but I wouldn't pay a premium for the privilege of having to do all of the demolition work that will be necessary to get the project started.

[J M Fahey]

Well, I did a very simple search for "tube pa into guitar harp amplifier" and just in the first screen I had all the answers.
1) To begin with, a YT video called : "Vintage Masco PA head conversion into guitar ..." http://www.google.com/url?sa=t&sourc...fAVSkskaPNZ6rw
so, guys, now you know it, start cleaning that incredible amount of junk ypu've amassed over the years and turn it into cash.
Oh !!! I see !!! , you are terrified that the buyer will ask *you* to do the conversion !!!!!
No worry, get thrown out of the game by stating that you are "un-vintage", mumbling, for example: "ok !, I'll replace all parts with a nice robot-made SMT board .... I'll program its microprocessor with a lot of vintage Kraftwerk sounds ..... " and so on.
Afterwards counterattack by supplying links to said video, and topping it with:
2) Vintage Guru approved step by step instructions:
Lone Wolf Harp Amps
The beginner-friendly chassis he suggests to work on:

Some pearls to be found there:
>" the esculating cost of vintage tube guitar"<
Don't ask me what that word can mean in Spanish
>"Replace all paper capicators."<
>"Replace coupeling caps with harp friendly caps"<
Now, what would a harp friendly cap be?
It's all there:

4. Replace coupling caps with harp friendly caps.
This is the number one mod to make any amp more harp family. The coupling caps in guitar amps as well as PA amps are designed for higher frequencies and we want to enhance the low end response so it is necessary to increase the value of the caps. The standard is .1uf with a rating of from 400 to 600v although you can go higher you do risk oscillations that produce a "motorboat" sound (put-put) if you do not have sufficient filtering and isolation for the preamp section. I will use .47uf caps in this amp and if I have any trouble I will replace them with .22uf caps.

Now, a .1 cap into a 220K grid resistor has a cutoff below around 8 Hz; he wants to go down to 2Hz; sure it will benefit the harp sound a lot !!!!!!!
The grid blocking will last 4 times as much as before. Good !!!! Very vintage!!!!
And motorboating provides a nice tremolo effect.
I have to recognize that in the end, this guy offers very good advice, which redeems him in my eyes:

If you chase every mod recomendation on every forum you will never be satisfied, you will spend more time modding than playing and your amp will be the worse for the ware.

[bob p]

I guess that explains it -- some guy posts a video on youtube about how to perform the conversion, and a million numbskulls who can only paint-by-numbers rush out to buy that exact same model of amp, with the intention of following his directions.

The problem is that some people don't have the sophistication to reject the utter rubbish that some of these people are publishing -- your filter frequency example is a good one.

We all know that these amps have been shelved for decades for a reason -- they all had problems that caused them to be removed from service, and it hasn't been cost-effective to repair them. Although they look kewl in a retro respect, if you can't service the amp yourself then the cost of having one serviced by a competent technician will negate any perceived "savings" compared to just buying a "modern" "expensive" tube amp outright.

Its funny -- people who know how to rebuild them don't want to take on the job, and people who don't know how to rebuild them don't know how prohibitive the labor costs will be. I think that there are a lot of people who buy these amps thinking that they are going to get a great deal and save a lot of money, and then they end up upside-down.

Caveat Emptor.

[JHow]

Orthography is SO over-rated.

[tedmich]

+1 with Bob these old greasy cooked PTP are a nightmare, usually only the iron is worth salvaging...

once the uniformly gray and brittle leads are labeled well!

[bob p]

OMG here's another $200 Masco amp. What is it about Mascos that makes them so special?

VINTAGE CUSTOM MASCO MA-17 TUBE AMPLIFIER AMP MIC PHONO - eBay (item 190403626944 end time Jun-20-10 19:14:26 PDT)

[J M Fahey]

QUESTION:

What is it about Mascos that makes them so special?

ANSWER:

a YouTube video called : "Vintage Masco PA head conversion into guitar

Just like that ?
Short answer: yep !!

[Marc]

Masco Mojo
They have it and all the harp players know this.
I've got a stack of tube pa's that are usually parts donors for on the cheap repairs.
Why buy new when old will do.
My operadio pa from 1939 is my pride and joy. It just looks so cool gathering dust on my shelf.....

[Sweetfinger]

There's a lot more to this than just one guy's youtube. Rebuilding old PA heads has been an underground thing for a while- I heard about it about ten years ago. There's guys who specialize in that work and they're full up with work, have been for years. What you're seeing now is the result of enough momentum, VG articles, and word of mouth that this is flowing over into areas that hadn't previously been aware of it. FWIW I have an old Operadio PA that has pristine wiring with no rust anywhere, just needed new E-lytics, one leaky PI coupler and pots lubed. I will eventually change the tone stack but it sounds and looks fantastic as it sits. As far as Masco- they're common and the name that gets mentioned. We're at the point where now even the more obscure off-brands are pulling some cash. Most of us wouldn't fault a musician who paid $1,000. for a custom hand-built amplifier that looks cool, why get your panties in a bunch just because the raw materials for that custom build come from old PA heads?

[Bill Moore]

I have to admit the old stuff is durable. Back in 1982 this shop was wired with AT&T's best telephone system, including paging. The cost got prohibitive, and the boss had the extra stuff removed. We really needed a paging system, and AT&T had left their horns and wiring. I put a fuel pump on our local music store's owners car, and told him I needed a power amp. He took me upstairs and handed me a round front RCA tube amp. I ran some wiring, and got a couple of shack mics, hooked it up to the horns, and it worked well. Fast forward to 1992 when I bought this place, was showing my wife the paging mics, and turned one on IT WORKED. The amp had not been turned off for almost 10 years! I made a present of it to my amp tech friend, and he traded it for something desireable. I doubt something new would have lasted any better.

[J M Fahey]

Have you seen that Woody Allen picture, where he wakes 200 years into the future, turns the ignition key on a dust covered WW Beetle he finds in a barn, and it actually starts, the engine purring like a happy cat?
His comment is: "they did build things well in the old days !!!"
I think the same applies here.