Fender 65 Super Blackface - your thoughts

[Cagey]

It'll work to a small degree, but it's poor practice. You end up with high voltage reflections on the plates of the power tubes so you run the risk of puncturing the insulation in the output transformer (and subsequently burning it up), or arcing either in the output tubes or on their sockets, which is also NFG. Used to be a common result of using some of the older "power soak" units.

Modern power attenuators are better designed so they present the proper impedance at the amp's output, then burn off the power before presenting it to the load (speaker(s)). If I had an older amp that only made me happy at high volumes, that's the route I'd go. And the Super Six/Super Reverb/Twin (or many of Fender's old non-MV amps) are prime candidates. This is especially true if you're looking to maintain "original" construction for resale reasons. You don't want to modify them, lest you frighten off a potential mental case suitor at sale time.

Weber makes some nice units that are reasonably priced; that's probably where I'd start if I were in the market.

 

[sully]

I did end up buying that amp. Won't be able to bring it home though till the first weekend of October.

I am not looking to mod it. But I am interested in ways to control the volume in different circumstances. In the end I decided to go with it because it is a good buy for the shape its in, and I do like the sound best of all I've personally played through.

The next year or two I guess will tell the tale as far as whether I bought something that is just too big for me.

When I get it here in person I will share it here. Might even get around to taking some nice snapshots of my guitar and sharing that as well. But since I just "blew my wad" as it were on this amp, I will be finding any odd-job I can to start the slow build back up.

Thanks to everyone for the information.

 

[Cagey]

Good for you! I'm sure you'll put it to good use. Worst case is you're less than thrilled, but there are a lotta people out there who like vintage amps, so you should be able to get your money back, maybe even plus some.

 

[Great Ape]

If your priority is a tone-loaded, heavy, too- loud- to- use- anywhere, undeniably great amp with some serious mojo, then buy it; the price is excellent, assuming it's all legit. Just bear in mind that it's way too loud for club gigs or 'rehearsal'--it would need to be turned down to the point that the 'Super' personality would not even be in evidence...great amp to own, but where to use it? I would suggest, if the classic Fender blues & rock tones are what you want, that you check out a Deluxe. You simply CANNOT go wrong with a Deluxe...also, the Blues Jr. is indeed worth considering; I've been doing club gigs of various sizes for many years, and have been using Jr.'s & Deluxes for all of 'em, for their weight, manageable volume, and great tone-and I mean GREAT tone!
Best of luck with your search-it's fun, and...IT NEVER ENDS!!!!!! :glasses10:   

 

[Re-Pete]

I did end up buying that amp. Won't be able to bring it home though till the first weekend of October.

I am not looking to mod it. But I am interested in ways to control the volume in different circumstances. In the end I decided to go with it because it is a good buy for the shape its in, and I do like the sound best of all I've personally played through.

The next year or two I guess will tell the tale as far as whether I bought something that is just too big for me.

When I get it here in person I will share it here. Might even get around to taking some nice snapshots of my guitar and sharing that as well. But since I just "blew my wad" as it were on this amp, I will be finding any odd-job I can to start the slow build back up.

Thanks to everyone for the information.

Hey, that's great to read. Good on you for taking the initiative.  :hello2:

Look at it this way too: Things like Attenuators & Load Boxes are getting more sophisticated these days, so if you find it's blowing your head off at even modest settings, an alternative (like hooking up an attenuator) is around the corner.

 

[Patrick from Davis]

I would google the death cap mod and fender amp.  It is very simple, and will decrease your chances of getting zapped while playing greatly.  Searching just "Death cap" brings up a lot of odd mushroom links...
Patrick

 

[sully]

I would google the death cap mod and fender amp.  It is very simple, and will decrease your chances of getting zapped while playing greatly.  Searching just "Death cap" brings up a lot of odd mushroom links...
Patrick

Interesting. I knew about the two-prong issue. I understood it that was prior to polarization of outlets, so the switch was used to set proper polarization. Lazy way of reversing the plug I guess.

I was not aware of the filtering cap, or noise-supression. I understand its intent though. This amp has the 3-prong installed, although I won't know if the cap was removed or not until I pick it up in a couple weeks. Either way, I don't relish the thought of "coming up to potential" so I will double check the work.

I know to discharge caps. Used to use a well insulated screwdriver attached to a ground to bleed some really large ones off, like from a computer monitor. Not something you want to do really, but does provide a good lesson in what could happen if you go sticking your fingers in electronic circuits (where they don't belong). Have yet to look at how to drain the caps on something like an amp without damaging it.

Your idea though did lead me to some general information on the precautions one might take to make sure the outlets are wired up correctly. I'm somewhat familiar with electricity, from basic wiring to some theory on transmission/distribution. I've never given any thought though to the fact that one outlet might be wired to one phase while another might be use a different phase. Familiar with delta phases on transmission, but not much like that on distribution.

Just some more interesting tidbits to stuff in my melon. Thanks for that tip!

 

[bagman67]

You can bleed the capacitor by bridging it with an appropriate value of resistor.  A quick google search got me here:
http://ampmaker.com/discharging-capacitors-946-0.html


There's lots more out there, including how to guess the time-to-discharge calculation based on resistor value and charge.  But as long as you have the cap bridged with the resistor using alligator clips, that will leave your hands free to monitor voltage with a multimeter as the cap bleeds off.

 

[sully]

You can bleed the capacitor by bridging it with an appropriate value of resistor.  A quick google search got me here:
http://ampmaker.com/discharging-capacitors-946-0.html


There's lots more out there, including how to guess the time-to-discharge calculation based on resistor value and charge.  But as long as you have the cap bridged with the resistor using alligator clips, that will leave your hands free to monitor voltage with a multimeter as the cap bleeds off.

Nice. I've a chopstick tool somewhere, although I will have to make a new one with a higher rated resistor. Mine was for 24vdc circuits so its not near enough.

I haven't looked yet, but was planning on doing some research related to the tube aspect. Meaning, what sort of "bad things" can happen if you don't discharge at the right point or in the right order. From pics I have seen, there seems to be quite a few caps, and not sure which one are involved in the circuit nor if they are all tied together or not.

Not something I need to worry about quite yet, but I am sure I will in the near future. That is after all one of my main reasons for a vintage, to be able to know it inside and out so when any servicing needs done, I know what has been done, what has not, and where to look for issues.

Thanks for taking the time to post that info!

 

[Patrick from Davis]

The big electrolytics are the guys to watch for.  Should be like a roll of dimes and probably blue, grey, or these odd things in a aluminum capped paper roll.  If they are the paper roll exterior, just go ahead and replace them.  They last about 10 years before times starts to wear on them.  They are all in parallel, sort of.  There will be one of those electrolytics at each stage of the amp going towards the input.  There are chokes or resistors between the caps as you get to the most "filtered" power section, where the input stuff resides.  However, once you put a resistor across the high voltage and ground rails, they all will drain.  You can watch, as noted in a previous post, with your mulitmeter.  Somewhere, =CB= had a way of adding a large value resistor to the circuit so that the amp would drain on it's own, but I must not have entered the right words to narrow down the search enough.  If you buy new caps, I'd get Sprague atoms.  They are a bit more expensive, but they are well known and reliable.  Should you unload the amp for any reason, it is a name that reassures buyers as well.  So you get that little bit of insurance included i the price.
Patrick

 

[sully]

@Patrick from Davis

Thanks. I do know a bit about caps although I appreciate any tips at any time Nothing is redundant when you actually want to learn IMO.

But I don't know about this circuit specifically, so sage advice is always welcome!

 

[Patrick from Davis]

The AB763 circuit was used in a lot of Fender amps.  The power section was different, and the transformers and speakers were also different to deal with those power levels, but the pre section is the same.  Hey, if it works...
Patrick

 

[mayfly]

The AB763 circuit was used in a lot of Fender amps.  The power section was different, and the transformers and speakers were also different to deal with those power levels, but the pre section is the same.  Hey, if it works...
Patrick

Yep - in the case of the super, 4 eight ohm speakers were all wired in parallel for a 2 ohm load (!).  A special output transformer was used for this amp.  I often wonder if that's part of the 'super sound'.