SWR Silverado Special 212 Combo Replacement Speakers

[agedhorse]

The Bass Place acquired the SWR Documentation? That’s new to me.

 

[D Rogue]

The Bass Place acquired the SWR Documentation? That’s new to me.

That's what the kind folks at Fender told me. They're closed today, so I'll cal tomorrow.

 

[Wasnex]

Again, I have no idea what my little test is telling me, but since I can't tell in difference in sound or speaker cone movement direction I'm going black/black (bottom lug) and red/brown on upper lug. What do you think?

It's not telling you anything useful.

Most likely the 0.4 ohm reading is ground to ground. Perhaps the calibration of the meter is off, or you are reading a small amount of resistance in the wires or between the contacts.

AFAIK the 3.6 ohm reading is measuring the path through some of the output devices in the amp and also the diodes in the power supply to ground. It's definitely not ground to ground.

AFAIK, the sleeve of the input is ground and the negative terminal of the speaker is also ground.


The output section of this amp is from the Bass 350 if you want to look at the schematic. The Bass 350 schematic does not label how the speaker is connected. However, the Bass 350 output section was also used for the Workingman 4004. The following graphic is from the 4004 schematic binder.

The output of the amp is 1 J5. This goes to the positive terminal of the speaker. Notice what 1 J6 indicates: "To GND at speaker jack." In every instance I know of, a grounded speaker jack is connnected to the negative terminal of the speaker.

You could trace the wires back to the amp and see how the components are connected.

 

[agedhorse]

Why bother? It doesn't provide any useful information without confirming what you are actually measuring.

 

[D Rogue]

Most likely the 0.4 ohm reading is ground to ground. Perhaps the calibration of the meter is off, or you are reading a small amount of resistance in the wires or between the contacts.

AFAIK the 3.6 ohm reading is measuring the path through some of the output devices in the amp and also the diodes in the power supply to ground. It's definitely not ground to ground.

AFAIK, the sleeve of the input is ground and the negative terminal of the speaker is also ground.


The output section of this amp is from the Bass 350 if you want to look at the schematic. The Bass 350 schematic does not label how the speaker is connected. However, the Bass 350 output section was also used for the Workingman 4004. The following graphic is from the 4004 schematic binder.
View attachment 3984724

The output of the amp is 1 J5. This goes to the positive terminal of the speaker. Notice what 1 J6 indicates: "To GND at speaker jack." In every instance I know of, a grounded speaker jack is connnected to the negative terminal of the speaker.

You could trace the wires back to the amp and see how the components are connected.

Thanks, man! Pretty much everything you wrote was my assumption (albeit not completely understanding what I was doing), and the screen shot of the wiring diagram, or at least my interpretation of it, solidifies what I was thinking. I'll look to see if the terminals are J5 and J6, which I bet they are. I'm looking at the whole drawing now, and it looks very similar, at least controls-wise to the Silverado Special. Does that amp, the Bass 350, have a horn? If so, I can't find it on the drawing... but I'm not good at reading these. If I could see how the horn is wired that would double confirm that I've got it right. I think I'm good to go, and am going to button it back up, minus putting the grill on, and tomorrow I can put the new speakers in. Thanks again for your help!

 

[Wasnex]

Why bother? It doesn't provide any useful information without confirming what you are actually measuring.

Instead of continuing to be cryptic, please explain how you would go about solving the problem.

 

[Wasnex]

Thanks, man! Pretty much everything you wrote was my assumption (albeit not completely understanding what I was doing), and the screen shot of the wiring diagram, or at least my interpretation of it, solidifies what I was thinking. I'll look to see if the terminals are J5 and J6, which I bet they are. I'm looking at the whole drawing now, and it looks very similar, at least controls-wise to the Silverado Special. Does that amp, the Bass 350, have a horn? If so, I can't find it on the drawing... but I'm not good at reading these. If I could see how the horn is wired that would double confirm that I've got it right. I think I'm good to go, and am going to button it back up, minus putting the grill on, and tomorrow I can put the new speakers in. Thanks again for your help!

The Bass 350 was a head, so no it did not have a tweeter.

I don't believe the website provides a dedicated schematic for your amp. You have to try and extrapolate a bit from available data IMHO. This is what I have tried to do throughout the thread. The way to be absolutely certain is to trace the wires back to the power amp module and see how they are connected relative to the components.

 

[D Rogue]

The Bass 350 was a head, so no it did not have a tweeter.

I don't believe the website provides a dedicated schematic for your amp. You have to try and extrapolate a bit from available data IMHO. This is what I have tried to do throughout the thread. The way to be absolutely certain is to trace the wires back to the power amp module and see how they are connected relative to the components.

I'm gonna roll with what I've got! I've taken pictures and notes, so if I can get a copy of the wiring diagram for this amp I can confirm then. The terminal strip is not numbered/labeled, but I feel good about this, and it sounded fine, so once I put the new speakers in it I'll call it a day and just play it. Thanks again for your help!

 

[agedhorse]

Instead of continuing to be cryptic, please explain how you would go about solving the problem.

Trace the wires to the terminal strip and trace out the circuit so that he knows for sure what he has.

 

[D Rogue]

Sorry, been tied up with other things, and had paused my bass amp project. So I just put in the Delta 12A speakers, and the amp sounds more or less the same... except now I can crank it. Sounds good, but I'll open it up a bit more later. I appreciate all of the advice, suggestions and comments, as it was a big help! I'll let you guys know how it goes in a band situation. Cheers.