Not enough amp?

[ericjschroeder]

I've tried to find the answer but maybe haven't looked far enough. I bought 2 Behringer items: a 450W amp and a
1200W cab. Without adding any effects or gain, I get an "ok" volume with this setup. I can add gain on the amp, or "phat" from my Ibanez bass for a nice boost, and I can boost the bass or treble from the amp too. However, if I run the effects In/Out loop through my (yes) Behringer 8-channel I/O thru the EMU 1616 sound card to Ableton Live and apply various effects, it literally shakes the walls, windows, etc.! Does that mean my amp by itself is not enough for this cab? Would a 1200W amp be better suited? How much is too much? Thanks, I'm not a techie when it comes to amps & cabs.

[GrowlerBox]

One quick thing to note about Behringer amps and cabs -- they rate power waaaaay too high. The amp possibly puts out 450 W at peak (it's probably 250 W RMS at best), and you'll be scraping bits of the cabinet and molten speaker off the wall if it ever gets a sniff of 1200 W. Apparently their electronics are OK, so your mixer probably isn't too bad as long as the knobs stay on.

So, in answer to your last 3 questions: no, no, and around 500 W tops (if you don't dime it).

Edit: sorry, changed an answer when I re-read the question. That last glass has almost worn off now....

[bongomania]

Your amp cannot produce more power "with" effects/processing than it can "without". So you don't need more wattage--it's no more than 450 W (and maybe much less) that's shaking your walls and windows! What's happening is probably one or both of these two things:
1) Compression. Any sort of distortion or fuzz creates compression, and maybe you're adding a regular compressor in your fx signal path, I don't know. Compression raises the average levels of your signal, which can make it seem much louder.
2) Resonance. This is when one narrow range of frequencies gets boosted much higher than all the frequencies above and below that range. A boost or resonant spike around 100 to 150 Hz will rattle your walls--again, with only 450 W.

[ericjschroeder]

Thanks for the really quick reply, but I'm not sure I understand all the replies. The tough thing is understanding which HW/SW is contributing what. My 8 channel I/O has a pot knob which certainly increases/decreases the volume. Ableton Live has volume/gain knobs and the various effects have features like: Gain, Noise Reduction, Bass Cab emulator, EQ, Compressor, Amp simulator, Flanger, chorus, limiter, etc. So I guess I'm wondering what is the limit of the cab and if there's a better amp. Growler says 500W max (what do you mean by 'dime it'?) but why wouldn't I want a 1200W amp (if it exists) for a 1200W cab? tx

[GrowlerBox]

Sorry again, I was being somewhat flippant.

I don't know what mixer you're using, so I don't know whether it will increase gain (i.e. uses power to amplify the input signal), or will merely (passively) cut it.

It's pretty much impossible to know what the actual specs on the cab are (Behringer are hardly alone in not publishing these), but the 1200 W rating is (at best) the power the voice coil of the speaker can take before it is irreparably damaged by heat. What it will take before distorting, "farting", etc is anybody's guess. Depending on the speaker(s) it contains, it may take a few, or possibly several hundred watts without crapping out. There simply isn't enough information given here to make any kind of estimate. But fear not, you cannot "underpower" the cab (although some will continue to claim otherwise).

Ignore the "500 W" comment; it wasn't especially helpful, although you figured that out already! . By "dime", I simply meant "turn the master volume up to 10", an Americanism I have acquired from spending too much time here, I suspect. Basically, listen carefully to what happens to the sound coming from the speakers as you slowly increase the volume, and back off as it starts to sound "off" (distorted, "farty", etc, as above). This will happen earlier with lower than with higher frequencies, as these demand more back and forth movement (excursion) from the speaker.

As for a better amp, sheesh, take your pick. For my money, find a tone you like, then pay attention to the power, form (weight, size, etc) and any extra features.

I hope that's a little more useful to you. And listen to Bongomania -- dude knows his effects (and more besides).

[bongomania]

Originally Posted by ericjschroeder

...why wouldn't I want a 1200W amp (if it exists) for a 1200W cab?

Well, you are already shaking your walls and windows with 450 W, so you don't really need more wattage. You just need to experiment with your signal processors to learn how they work, and which ones do the most rattling of walls. Let's say for example that the fx chain you happened to set up included a big boost in the mids and low mids, and some overdrive, and a compressor. Even without increasing the wattage, you have just massively increased the "loudness".

Watts =/= Volume.

Watts are part of the puzzle, but only a part, and maybe not even the biggest part.

[Stumbo]

Is your 1200w cab 8ohms?

The amp may be looking for 4ohms for max output.

[ericjschroeder]

Originally Posted by Stumbo

Is your 1200w cab 8ohms?

The amp may be looking for 4ohms for max output.

both are rated 4ohm.

Amp:
ULTRABASS BX4500H

450 Watts into 4 Ω

Cab:
ULTRABASS BB410

4 Ω

[ericjschroeder]

Originally Posted by bongomania

Well, you are already shaking your walls and windows with 450 W, so you don't really need more wattage. You just need to experiment with your signal processors to learn how they work, and which ones do the most rattling of walls.

True but only doing the real shaking with the effects chain. Without, it gets an ok volume but not massive. And cranking it from 5 to 10 doesn't seem to boost it that much, but I haven't messed with the gain much. The downside to using Ableton Live for my effects is I have to deal with latency and/or clipping which is a drag. I am trying to avoid having to spend any more money right now. Oh, well, I guess I have even more learning to do, trying to get all these different HW and SW to play nice with each other.

Just ran back to test something. I plugged my bass into the 450W amp/1200W cab and turned the volume up to 10. Then I switched to my 75W Peavey combo amp and cranked it up to 10. It actually sounds louder and vibrates the walls more than the big one! And my return date just past for the big amp. DAng! Well, I suspect the small amp couldn't handle the effects chain so I guess it's a keeper. Considering how heavy it is, I'd like to get the most out of it, not feel like I wasted my money. But it is the least expensive setup.

[GrowlerBox]

Coupla things. Given that your primary endeavours seem to involve domestic demolition rather than searching for a particular tone (), re-read what Bongo has written concerning the particular frequencies involved in rattling your surrounds. Do some playing with your EQ to determine which frequencies do what. It is not all about volume. The relative loudness of your Peavey combo compared with the Behringer rig suggests either that your Behringer is even more power-overrated than I thought, or the Peavey has more going on in the lower and middle-mids, or a combination of these.

Also, be careful turning that Peavey up to 10, especially if you have much bass dialled in. The speaker won't last long. Do what you like with the Behringer, the sooner you kill it, the better .

[christw]

Originally Posted by ericjschroeder

True but only doing the real shaking with the effects chain. Without, it gets an ok volume but not massive. And cranking it from 5 to 10 doesn't seem to boost it that much, but I haven't messed with the gain much. The downside to using Ableton Live for my effects is I have to deal with latency and/or clipping which is a drag. I am trying to avoid having to spend any more money right now. Oh, well, I guess I have even more learning to do, trying to get all these different HW and SW to play nice with each other.

Just ran back to test something. I plugged my bass into the 450W amp/1200W cab and turned the volume up to 10. Then I switched to my 75W Peavey combo amp and cranked it up to 10. It actually sounds louder and vibrates the walls more than the big one! And my return date just past for the big amp. DAng! Well, I suspect the small amp couldn't handle the effects chain so I guess it's a keeper. Considering how heavy it is, I'd like to get the most out of it, not feel like I wasted my money. But it is the least expensive setup.

Turn up your gain knob. That's your problem. Gain is your preamp's boost, where you should be seeing a lot of your basic signal's amplification.

[billfitzmaurice]

Originally Posted by christw

Turn up your gain knob. That's your problem. Gain is your preamp's boost, where you should be seeing a lot of your basic signal's amplification.

+1. If the amp is louder with effects than without it's a gain structure issue, not power. The effects setup you're using is not unity gain. If the effects return has a volume control use it to balance the dry/effect levels.

[bongomania]

Originally Posted by ericjschroeder

I plugged my bass into the 450W amp/1200W cab and turned the volume up to 10. Then I switched to my 75W Peavey combo amp and cranked it up to 10. It actually sounds louder and vibrates the walls more than the big one!

...Which should be proof enough for you that wattage is not the issue here.

[christw]

Originally Posted by bongomania

...Which should be proof enough for you that wattage is not the issue here.

I'm getting the impression that the gain knob is near minimum right now.

[ericjschroeder]

Originally Posted by christw

I'm getting the impression that the gain knob is near minimum right now.

Yes you're right. The Peavey doesn't have a gain knob so I haven't dialed it up yet on the Behringer, which is a 4x10. The Peavey is a 1x15.

Thanks for all the suggestions and feedback. Sometimes learning is fun, other times it's a real pain.