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Discussion Starter #1 (Edited)
Bought at a pawn shop this week for 699 tax inc.

Here's the pics. Can any of the techs here comment on the condition of the guts?

It sounds a little ratty at high volumes. How do the caps look?

One speaker is changed/new-ish russian tubes with the exception of two chineese 12 ax7's.

Anyway here's the photo tour:









Best regards,

Brian
 

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Brian, the amp looks in great shape!

Still, one thing about electronic parts. They can look just fine on the outside but be totally snackered internally! Like most things in life, good looks is no guarantee of good performance.:smile:

Since the amp sounds ok but just a bit ratty at high volumes there could be a few things that could stand some attention.

The speakers may be old and the cones breaking down. Or the cab may be coming a bit loose in the glue joints and you're getting some vibration from the wood. Try an extension cab and that will confirm it one way or another.

The electrolytics (dual units, brown guys with 2 wires at one end and one wire at the ground end) appear to be original. That means the power supply electrolytics that are under the "dog house" metal cover on the top of the chassis are probably original too. These dry up internally over the years and stop doing their job, which in the power supply is to filter out all the power supply hum and in the preamp circuits along the eyelet board they put big gobs of gain in each 12AX7 stage.

Even if you aren't hearing much power supply hum old filter electrolytics can cause weird noises and ghost notes. The smaller ones in the preamp will drop the gain a whole bunch! Yet these caps may look pristine from the outside.

Electrolytics have a wet paste inside which slowly dries up even if the amp is never used. Heat speeds up the process but even in storage it still will continue. Normal expected life for these caps is 10-20 years. How lucky do you feel?:eek:

Those big blue couplers are kinda chintzy, too. Fender was saving money. I'd rip 'em out and put in Orange Drops myself. That's just my personal taste.

The nice thing is that it appears no one has dinked around with the wiring! Makes things so much easier for a good tech to work on.

Anyhow, that's about all I can say. I suspect the old caps may be causing the "rattyness". A complete cap job on an amp of this age is always a good idea, period. If the rattyness then disappears then great! You still won't be sorry!

Who knows what the bias setting is, either. Old tubes may be the problem.

All in all though, a great score!

:food-smiley-004:
 

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Fantastic looking amp !!

Thanks for all the chassis/board pics...I try to learn whatever I can from these.

Also enjoyed Wild Bill's reponse. Like a mini tutorial. His writing style is so easy to comprehend. Maybe we can convince him to write a book about amp repair/building...in his (cough) spare (cough) time.

Enjoy the amp!!

Dave
 

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Discussion Starter #10
Thank you Bill for having a look!

I was hoping you would comment. I have read most of your posts. You are a very helpful person.

I did try the vibrolux plugged into the 16ohm green back that is in my other amp. Most of the rattiness cleared up. It looks like it might be a speaker issue.

For now this amp will be staying at home...I bought a handle for it but thats about it.

I'll start looking for replacement speakers but having just spent $2000+ on a 65amps SoHo I don't think there's much money left in the budget for all things amplifier.

What would a complete cap job cost? I would think it would be wise to save all the original parts.

I finally tried the vibrolux with a FDII as a boost.....does this amp ever rock! Sounds great with my old Les Paul.

It's not as loud as I thought it would be but still waaaaaaaaaaaaaaaay too loud for around the house.

I'm not sure if the transformers are going to like this but I've got it plugged into a DR Z Airbrake set to maximum attenuation.

The sound of a strat plugged into this amp when its between 6-10 really is something.

So my next question:

Will running it into an airbrake hurt this amp?

Again, my thanks.

Best regards,

Brian

PS

If you were changing out the speakers what would you use?

B
 

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Hey there...beautiful amp!..here's my 2 cents for what it's worth...Wild Bill is right, the electrolytics have to go as they are a liability due to their age..however, I wouldn't rush to replace those blue mylar type coupling caps. Have them checked . In my experience, they are one of the better caps Fender used. The bad ones came later in the '70s (brown with yellow lettering) they were sh*t. In my opinion, they contribute to the blackface sound. One thing that should be checked if you notice crackling and hissing is the bias resistors in the preamp circuit. They can cause a lot of headaches if they're bad. :smile:
 

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What would a complete cap job cost? I would think it would be wise to save all the original parts.
Don't bother! Would you save old brake shoes from your car? With electronics, the old parts are junk. They can't be repaired. They are far too common to be museum pieces. They are never going to go back in your amp. Give them a brief ceremony of respect for all the music they helped create and then trash 'em!

As for cost, if it were my shop it would be around $120-$140 dollars. That's parts and 2 hours of labour. The time would also include inspection and checking voltages, testing tubes, checking the bias on the output tubes and cleaning all the controls. Other shops will likely have a different labour rate than mine. Just remember that if the rate is too cheap you might be wise to wonder why! Also, if the tech doesn't mention it be sure to have it understood that if he finds some scary expensive surprises he or she will stop and phone you first with a "heads up" and not just hand you a bill far larger than you expected.

Don't let whoever does the job forget to change the electrolytic in the bias voltage supply! That one is often forgotten.

I'm not sure if the transformers are going to like this but I've got it plugged into a DR Z Airbrake set to maximum attenuation.

The sound of a strat plugged into this amp when its between 6-10 really is something.

So my next question:

Will running it into an airbrake hurt this amp?
Don't see why. Airbrakes and hot plates are simply "power soakers". They change electrical audio energy into heat. Electrically you can think of them as simply dummy speakers that don't put out any sound.

If you were changing out the speakers what would you use?

B
Eminence recommends their Legend series of speakers to stay true to the vintage sound of these amps. However, speaker taste is a very personal thing. They have a lot of great sounding models that you might like BETTER than the stock sound.

I'm far more of a solder sniffer than a player. Hopefully someone with more experience like a soundman (Milkman around?) or someone who's played your amp model a lot with other speakers will chime in.

:food-smiley-004:
 

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Hey there...beautiful amp!..here's my 2 cents for what it's worth...Wild Bill is right, the electrolytics have to go as they are a liability due to their age..however, I wouldn't rush to replace those blue mylar type coupling caps. Have them checked . In my experience, they are one of the better caps Fender used. The bad ones came later in the '70s (brown with yellow lettering) they were sh*t. In my opinion, they contribute to the blackface sound. One thing that should be checked if you notice crackling and hissing is the bias resistors in the preamp circuit. They can cause a lot of headaches if they're bad. :smile:
Yeah, the blue ones aren't so bad I guess. I still like the ODs. It's all taste.

I agree with you completely about the brown ones!:eek:

:food-smiley-004:
 

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Besides changing capacitors, you must change the power cord to a 3 wire grounded type for your personal safety.
 

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Besides changing capacitors, you must change the power cord to a 3 wire grounded type for your personal safety.
Thanks Gunny.....I was hoping that someone would suggest this, but I was also concerned that if I mentioned it, 55 Jr might be offended as it was quite obvious and he seems to know a lot about amps.

That said, any noobs that read the thread should be made aware of this safety concern just in case they by an amp with the same 2 prong AC plug and don't realize the hazard. It is amazing how many 2 prong plugs are still on used amps being sold.

Dave
 

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Besides changing capacitors, you must change the power cord to a 3 wire grounded type for your personal safety.
Actually, this is one of those "always a good idea but not the first on the list" type things! Do people really think that electrocution was a daily occurence before we switched to a 3 wire system?:smile:

Even with a two wire system you have protection from the isolation of the power transformer. If you were standing in a basement puddle of water playing your amp you might get a slight tingle but that should be it.

What CAN happen is that the capacitor used in the ground reverse switch circuit could short and this could make the chassis dangerously "hot", but this is a very rare thing. Being so flipping old I can truthfully say that I've seen this happen, but only twice in over 45 years of playing with electronics.

I usually tell guys that when you have the amp to a tech and he's gonna have the chassis out anyways you should have the cord changed. It will only be a bit of extra time, that way. Just make sure that when he changes the cord he also removes the ground switch/cap wiring!

You wouldnt' believe how many amps I see where they put in a 3 wire cord but left the "death cap", totally defeating the value of the 3 wire cord!:eek:

:food-smiley-004:
 

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Actually, this is one of those "always a good idea but not the first on the list" type things! Do people really think that electrocution was a daily occurence before we switched to a 3 wire system?:smile:

Even with a two wire system you have protection from the isolation of the power transformer. If you were standing in a basement puddle of water playing your amp you might get a slight tingle but that should be it.

What CAN happen is that the capacitor used in the ground reverse switch circuit could short and this could make the chassis dangerously "hot", but this is a very rare thing. Being so flipping old I can truthfully say that I've seen this happen, but only twice in over 45 years of playing with electronics.

I usually tell guys that when you have the amp to a tech and he's gonna have the chassis out anyways you should have the cord changed. It will only be a bit of extra time, that way. Just make sure that when he changes the cord he also removes the ground switch/cap wiring!

You wouldnt' believe how many amps I see where they put in a 3 wire cord but left the "death cap", totally defeating the value of the 3 wire cord!:eek:

:food-smiley-004:
Thanks Wild Bill...always enjoy and learn from your posts.

You really should consider writing a book...your writing style is so easily understood and humorous* (*meaning in a good/teaching sort of way).

Dave
 

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Lovely amp, and a good price, in my opinion. +++ to the expert opinion above. On a general note, having the original power cord archived in a bag might be an eventual selling point, and taking the original (matching no.) speakers out before they blow and archiving them would definitely be a plus for any subsequent resale.

The folks over at TDPRI seem to have discussed speakers quite a bit, and the name Weber comes up often, although I've never owned them. For little do-dads like the missing knob, Angela seems to have a decent selection:

http://www.angela.com/

On a collector's note, I wonder how close to the end of the run of "Fender Electric Instruments" faceplates that amp is? What is the two-letter date code on the tube chart, and is it an AA964? Teagle and Sprung (p.100) list those two 10's as Jensens. As an aside, my Oct. '62 Bassman reads "Fender Elect. Inst. Co."

Pricewise, that amp would have been much more in a retail environment in Toronto. If it was me, I'd have few reservations about throwing another $400 into it for speakers and a tech's attention. The ceramic 10" Jensen reissues I bought last year for about $70 each new (C10Q) are OK but not great speakers, but were half the cost of the Alnico reissues.
 

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OK, OK, I see it... "OB" is 1965 February, and the "AA864" makes me wonder if there is a misprint in Teagle & Sprung, or a difference between August and September 1964 design specs that took five or six months to appear on the production line.
 

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Discussion Starter #20
Hello all.

I took the kids camping at Jasper this week.

Had lots of fun....been away from the computer.

Again, my thanks to all for the info on the amp. I did have a chance to crank her a bit when we got back.

It still sounds a bit ratty at cranked volumes. Right now my 65amps SoHo does a better cranked blackface tone than the real thing.

:)

It really sounds good with the old Les Paul. I haven't tried it with my 68 tele yet.

It works well with my Vinage Icon and Ibanez strats.

The rattiness seems to clear up after the amp has warmed up fo 15-20 min.

Very good info from Wild Bill on the three prong/but forgot about the death cap upgrade.

I had that very thing happen to me with a 65 Deluxe Reverb I once owned.

Regarding the caps job/speaker replacement....after some soul searching/contemplating selling a resonator guitar I have decided to sell a few stocks and get this done right.

I'm still very concerned about a quality tech in the Edmonton area. Don't get me wrong, I'm sure there's some good people working on amps in this area....but they don't seem to appreciate the fact that they would be working on a valuable vintage amp.

I am seriously considering shipping to either Clara amps in Calgary or ship to Wild Bill himself.

Given his helpful advise on this on other threads that seems appropriate.


While the amp is out gettin worked on I'll start the speaker replacement search.


Thanks again to all!

Best regards,

Brian
 
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