makeshift stack....???

[RumbleSteve]

Ok, I started off with a fender rumble 150. Has a 15 at 4 ohms. I have not found a max power handling for the speaker. Then found a steal of a deal, hartke ha4000 head.....then added a hartke 410xl bass module, 240 watts @ 8 ohms. I currently run the head into the 410 with 290 watts @ 8 ohms. And from the ha4000 pre amp out XLR to the combo 150's 1/4 input. I have ran this setup for 6+ month's. The rig requires me to run both head and combo, powered. Not a big deal, but i would like to extend my rig to get the absolute most out of it. however, doing the math, i would have to change all the speakers to get the max load from my head (400watts @ 4ohms) . Despite my need for more air movement and earth shaking rumble, i just need to know that how i am ruuning my equipment is the most proper way without destroying it.?.?.???..??? I would love for this thread to progress as i found nothing, absolutely nothing about what Im doing on the interweb. Is this a safe method of rock'n out?????

 

[ashtray]

You just need an 8 ohm 15" speaker, then you can run the 15 and 4x10 off the Hartke - but you'll probably get more headroom out of your current setup.

 

[RumbleSteve]

This is true, but I'm not sure if the 410 will handle the 400w @4ohms. The more i think about it, the more this is a case of don't fix it, if its not broken. I am happy to be lucky enough that all of my equipment works together just fine.

 

[AlexanderB]

Hooking up a second cab will reduce (not increase) the power sent to your current 410.
Finding an identical cab is the easiest, safest way to go.
I personally would guess the 15" combo does not really contribute that much to the total capability of your rig.
Do a search or wait for more guys to tell you what I just said...

 

[jthisdell]

Could you not run fx send from hartke to fx return on the fender?

 

[BurningSkies]

This is true, but I'm not sure if the 410 will handle the 400w @4ohms. The more i think about it, the more this is a case of don't fix it, if its not broken. I am happy to be lucky enough that all of my equipment works together just fine.View attachment 526209

That's not how it works. You have an 8ohm cab. It won't 'handle' anything at 4ohm ever. It will always be an 8ohm cab. The Hartke HA4000 will produce 220w into an 8ohm load. I'd caution you from attaching the HA4000 to both a 8ohm 410 and a 4ohm 15 because that produces an impedance of 2.67, which is below where the Hartke can safely be operated. It also provides twice as much wattage to the 15 as the 410, thus making it dangerous to the well being of your 15.

In running both cabs off the Fender, the inputs of those combos are usually run in series, so you're getting less wattage due to increased impedance but with more speaker area are probably getting more volume.

 

[will33]

Without changing speakers/buying more stuff, you're getting the most you can out of it right now.

I'd just keep an eye out for another Hartke 410, making that rig your big stack and leaving the combo what it is.

For now I'd run like you are, except patch from the 1/4" effects send on whichever amp you like the preamp tone of the best, to the 1/4" effects return of the other.