SM400 for Bi-Amp Rig

[chadds]

While it would work, you would have two issues:

1) assuming you would be running 8ohms per 'side', you'd only be putting about 140 watts into the low end. That's probably not enough, and I don't think the extra cab and crossing over will make up for the volume drop versus your current bridging at 8ohms.

2) Just because a cab has an 18 in it doesn't guarantee it will handle those sub harmonics and huge low end that amp puts out.

Even though it will run hot, I think you can bridge to 4ohms with that amp. So, probably doing that into a second 212 would give you the most 'bang for your buck.

That 140 watts aside is not enough I agree. Bridging at 4 ohms is possible but the least efficient as more power is drawn from the wall than is generated as sound. I just read the owners manual. It can get quite hot and may need a rebias because of it.

For your sound goals what do you want?
Do you like your bass's sound?
The Pre of the SM-400?
Have you tried the eq suggestions from above?
The Output stage?
The whole head?
Have you tried that head on other cabs?
Do you like your cab?

 

[Count Bassie]

Oh, it's possible that 140 is enough for the lows. You running your band with PA? Subs?... You don't need big volume for stage. We're having a conversation on Facebook about this 'headroom' thing, and it's an interesting one. The trend is to need more power- but I don't think you necessarily big watts. Thoughtful choice of enclosures and eq savvy will take you quite a long way in the modern arena.

You don't need to move your audience' hair around to be understood.

 

[chadds]

Oh, it's possible that 140 is enough for the lows. You running your band with PA? Subs?... You don't need big volume for stage. We're having a conversation on Facebook about this 'headroom' thing, and it's an interesting one. The trend is to need more power- but I don't think you necessarily big watts. Thoughtful choice of enclosures and eq savvy will take you quite a long way in the modern arena.

You don't need to move your audience' hair around to be understood.

I don't wish to argue. I've owned two SM-400s with four SWR cabs. One side at 8 ohms is 160 watts actually. It's weak. The 220 watts at 4 ohms is better. Bridged into one 8 ohm gets you a decent roar.

Your suggestion is philosophical. There are so many variables. I've used a Polytone 100 1x15 combo in Golden Gate Park reinforced by a huge sound system. The side fills we're JBL 15s and it was glorious. I was the only electric instrument in this group. I wouldn't tell the OP that that is enough if he's up against some loud guitarists.

 

[Count Bassie]

I don't wish to argue. I've owned two SM-400s with four SWR cabs. One side at 8 ohms is 160 watts actually. It's weak. The 220 watts at 4 ohms is better. Bridged into one 8 ohm gets you a decent roar.

I wonder if the weakness is solvable with the mod to nix the aural enhancer? And hi-pass out the very low-bass...

No wish to argue at all, just bringing up something that's been on the table elsewhere. Hey, have fun!

 

[chadds]

I wonder if the weakness is solvable with the mod to nix the aural enhancer? And hi-pass out the very low-bass...

No wish to argue at all, just bringing up something that's been on the table elsewhere. Hey, have fun!

Cool
I did hook up all those short patch cords and it sounded weak. The full range sound was full. The amp is wonderful and a classic.

 

[Count Bassie]

Cool
I did hook up all those short patch cords and it sounded weak. The full range sound was full. The amp is wonderful and a classic.

When I had one I had some cabs I was afraid of hurting with the lows... I sold it. Sorry now! Anyway glad you're getting along well with it, yes indeed it's a great amp.

 

[chadds]

When I had one I had some cabs I was afraid of hurting with the lows... I sold it. Sorry now! Anyway glad you're getting along well with it, yes indeed it's a great amp.

Oh my two are long gone.
They were replaced by Bass 750s with GIIIs.
Those are also gone. I found gas freeness and less weight and higher performance.

But, I never could get enough lows actually. I never cranked the bass eq but used my bass's 18v pre. The only cone flapping I ever saw was when I tried a Reeves on my GIII. Sent it back!

I think SWRs do fine with their own cabs.

 

[Count Bassie]

Oh my two are long gone.
They were replaced by Bass 750s with GIIIs.
Those are gone. I found gas freeness and less weight and higher performance.

But, I never could get enough lows actually. I never cranked the bass eq but used my bass's 18v pre. The only cone flapping I ever saw was when I tried a Reeves on my GIII. Sent it back!

I think SWRs do fine with their own cabs.

Best sound in a club I ever heard was a Bassic 350 into a Goliath-II. Really, best bass tone ever. Floored...