Incoming Yamaha 410 Amp with 'crackling' issues...

[Amp]

Obviously I may be completely wrong but this strikes me as one of those old logic problems like they had on the college prep tests.

If that were the case, the answer seems as if it would be



Which only really leaves me with the shortened terminal to deal with, however there's enough there to solder to, if need be. I think I'll give this a try unless someone comes on and tell me it's a horrible idea and I'll be blowing up a perfectly good amp in doing so.  :lmao:

[J M Fahey]

Nope, sorry.
You are comitting 2 sins for the price of one :
1) you are wiring them in parallel, total impedance 2 ohms.
The Yammy won't like it.
2) the speakers are out of phase= weak distorted sound, no headroom, no bass. Ugh !!

Don't the speakers have a red dot at a terminal, or a "+" sign?

[Roly]

HTH

[Amp]

That sure does help. I got down there with a flashlight and the + / - arrangement on the speakers is literally the exact opposite of that  :dbtu:

So, I have a black and a white wire descending from the chassis.
On your diagram, I assume that my 'white' would be your red wire?

[J M Fahey]

OK, redraw them showing clearly the + terminals, and post it in an editable format (.gif preferred, not .pdf)

[Amp]

In the case of my amp, the arrangement would be:

[Roly]

The actual polarity makes no difference, it's the relative polarity that matters.

[Amp]

Good deal.
So I assume then that your red is my white?

Please bear in mind fellas that I am really, really new to this.
A couple of occasions so far, I've almost been shook loose from following along. For example:

You may make a new terminal bridge out of a piece of PCB, but to connect the terminal to the VC wires,you'll need some of the ultra flexible one (tinsel wires?) specifically made for that use.
You'll have to get it from some speaker repair guy, it's stuff not sold over the counter at Electronics shops.
Do not place it neither too tight (you'll tear it from the cone) nor too slack, where it may bump against the cone or even worse, short against the frame.
Place it in an "S" shape.

Saw me looking up the meaning of the following:

PCB
Terminal
VC Wires
Tinsel Wires
Cone

:lmao:

Of course, this internet thing is a rather incredible way to learn.
Sitting here with this broken amp in front of me just playing along in this thread with you fellas over the past couple days and doing it hands-on has earned me a beginners  education that would've probably taken a few weeks, if not more, of bookstudy in a classroom to achieve.

[Roly]

So I assume then that your red is my white?

Yeah, white wires on a white background don't show up all that well.   

PCB - Printed Circuit Board.
Terminal - the metal lug the wires are soldered to.
VC Wires - Voice Coil wires; wires leading to the driving coil of wire inside the magnet, called a "voice" coil for historical reasons that are now obscure, but it stuck.
Tinsel Wires - ditto, a.k.a. "braids", very flexible multi-strand cloth-cored wires used to connect the terminals to the back of the cone.
Cone - the conical cardboard bit that flaps back and forth.

The cone "suspension" comprises a flexible "spider" behind the apex of the cone, and the cone edge is supported by the "surround".

Some other 'speaker* terms;  {*sometimes the loudspeaker itself is called a "driver" when discussing loudspeaker systems in detail and the whole enclosure is then called a "cab" for "cabinet", or a complex cabinet such as a horn is called a "bin", to avoid confusion; the front plate the driver mounts on is called the "baffle".}









What we deal with here is workshop practice and it is quite different from what is taught in Colleges.  I had 12 years of math and theory but I learned how to actually do things at the bench from my mentor who was both a senior tech and a qualified electronics engineer.

[Amp]

Hooray!

Per Roly's wonderful suggestion, I've run the wires according to that scheme and we now have FOUR FULLY FIRING SPEAKERS  :dbtu: :dbtu: :dbtu: :dbtu: :dbtu:

Boy, these amps sure are fantastic. Talk about underrated.

Thanks so much for the help guys.
You walked me from broken amp to now a working amp.
Gives me a bit more confidence for when I finally run into that project that requires more advanced troubleshooting and possibly even... gulp... soldering.  :duh

[Roly]

That's excellent.   :dbtu:

To learn to solder, take some tinned copper wire and weave it into a 10x10 matrix of 1cm/half-inch squares.  Now solder up all the intersections.  If you are not on top of it, do a second one.  If you are still not on top of it, take up flower arranging.