SWR Silverado Special Extension Cab

[sidewinder88]

Hi Guys, I am looking to add an Extension Cab to My SWR Silverado Special.
The Internal Cab has 2 speakers running at 4 Ohms. The Amp can power an additional 4 or 8 Ohm extension Cab and go as low as 2 Ohms safely.
Should my extension cab be 4 Ohms for even power distribution? Should I stick to 2 speakers or could it be 4 speakers? Thanks!

 

[ihixulu]

Is the Special the 212 version? If so, each internal speaker is 8 ohms. To even out the power handling across drivers, you can add a one speaker 8 ohm cab (like a 115) or a 2 driver 4 ohm cab (a 212).

 

[sidewinder88]

Is the Special the 212 version? If so, each internal speaker is 8 ohms. To even out the power handling across drivers, you can add a one speaker 8 ohm cab (like a 115) or a 2 driver 4 ohm cab (a 212).

It is the special. Your answer confirms my suspicion that a 2 driver cab totalling 4 Ohms is what I need

 

[ezstep]

For a few years, a Silverado Special on top of a second SWR 2x12 cab was my main rig. The ext. cab (mine) was 8 ohm, meaning the two internal 12's received more power, running the amp at 2.67 ohms. But the rig was awesome. Eventually old age caught up to me.... lol. But I never had an issue with it.

 

[agedhorse]

I don't recall that amp being able to drive 2 ohms safely, it may only be able to drive an 8 ohms safely extension. I don't think I have the docs on this model either.

 

[brianrost]

Following up agedhorse's post above, I owned an SWR Baby Blue that according to the manual could handle 2 ohm loads.

I did in fact try this at home adding a 2-10 Peavey cab rated at 8 ohms (total load of 2.67 ohms) and the first thing I noticed was the amp chassis got really hot to the touch, like touching a toaster. When I went to unplug my bass, the metal shell of the cable was hot!!! I also heard breakup in the speakers as if the amp was clipping at a low volume. It didn't raise the wattage by much…the manual claimed 160 watts at 4 ohms, 180 watts at 2 ohms. Overall, I was uncomfortable with it and never actually used it with an extension cab on a gig.

Check your Silverado manual first to make sure it says 2 ohms are OK, but even if it does I wouldn't recommend it.

 

[Jugghaid]

I ran mine on top of an 8 ohm Eden 115. 2.6 ohms.

 

[sidewinder88]

Following up agedhorse's post above, I owned an SWR Baby Blue that according to the manual could handle 2 ohm loads.

I did in fact try this at home adding a 2-10 Peavey cab rated at 8 ohms (total load of 2.67 ohms) and the first thing I noticed was the amp chassis got really hot to the touch, like touching a toaster. When I went to unplug my bass, the metal shell of the cable was hot!!! I also heard breakup in the speakers as if the amp was clipping at a low volume. It didn't raise the wattage by much…the manual claimed 160 watts at 4 ohms, 180 watts at 2 ohms. Overall, I was uncomfortable with it and never actually used it with an extension cab on a gig.

Check your Silverado manual first to make sure it says 2 ohms are OK, but even if it does I wouldn't recommend it.

The manual does claim the Silveraod can be run at 2 Ohms safely

 

[sidewinder88]

I ran mine on top of an 8 ohm Eden 115. 2.6 ohms.

Did it sound more fuller and louder even with an 8 Ohm extension cab?

 

[Jugghaid]

Did it sound more fuller and louder even with an 8 Ohm extension cab?

Yup. That particular amp sounds really good anyway, but a D115T really rounded it out with those bag end 12" speakers.

 

[sidewinder88]

I'm thinking an SWR Triad would be a perfect match for this amp

 

[agedhorse]

I show that the Silverado combos can support an 8 ohm extension only, not rated to drive a 2 ohm load. This makes sense given the power amp design and heat sinking for this circuit. I bet it gets really hot at 2.67 ohms, a big challenge with all SWR amps of this era that didn't have fans.

 

[lowdownbp5]

I show that the Silverado combos can support an 8 ohm extension only, not rated to drive a 2 ohm load. This makes sense given the power amp design and heat sinking for this circuit. I bet it gets really hot at 2.67 ohms, a big challenge with all SWR amps of this era that didn't have fans.

I had a Silverado combo aged horse is correct

 

[sidewinder88]

I had a Silverado combo aged horse is correct

Mine is a Silverado Special and the manual states it can operate at 2 Ohms

 

[agedhorse]

Mine is a Silverado Special and the manual states it can operate at 2 Ohms View attachment 7253918

This may have been updated after the overheating issues in the field became obvious.

This was a common theme throughout SWR's earlier years, and something Fender addressed under their ownership.

 

[sidewinder88]

This may have been updated after the overheating issues in the field became obvious.

This was a common theme throughout SWR's earlier years, and something Fender addressed under their ownership.

Are you certain there isn't a difference between the Silverado and the Silverado special in that regard?

 

[agedhorse]

Are you certain there isn't a difference between the Silverado and the Silverado special in that regard?

Many of the SWR amps that claimed 2 ohm operation ended up not doing all that well at 2 ohms. As the products were revised, the ratings were revised to eliminate 2 ohm support with a few exceptions where Fender did either a redesign or added fans, updated the power supply, etc.

The Silverado and Silverado Special both fall into this category if I'm remembering correctly.

 

[Jugghaid]

Mine got warm but not overly so. Never ran it below the 2.67 load though. You also didn't need to push it very hard to get it to gig volume.

Found sn old pic

 

[sidewinder88]

I guess I should look for n & Ohm cab then .
Thanks guys

 

[sidewinder88]

Oops I meant 8 Ohm