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Changing Ohm load without adding cabinets?

S

Selios

Jun 20, 2012
312
375
Niagara, ON, Canada
#1
Hello,

Sorry if this has been asked before but I couldn't find anything helpful; is it possible to change the ohm load that your amp sees without adding more speakers or buying a cabinet that has a different resistance rating? Does such a device exist to make this happen?

I ask because I recently bought a Warwick LWA 500 micro amp that I really like, but my only cabinet (an 8 ohm 4x10) doesn't allow the amp to run at its full 500 watts. This amp's extremely small size and weight is an important factor to me (shoulder injury and space limitations when travelling with bandmates, merchandise, etc.), but I am used to having lots of headroom as I came from using a rack-mounted Ampeg SVT 5-Pro. With only 250 watts at 8 ohms I seem to be running the amp just about at its limit; it isn't struggling but I basically have nowhere to go in terms of volume against heavy drums. If I were ever to need to turn up the volume at a gig, the amp would be getting into clipping territory. It is well-documented on this forum that these Warwick amps do not sound good as soon as the clip light engages.

I would like to get the full power of the amp without either buying another 8 ohm cabinet or buying a 4 ohm cabinet. I don't have the budget for that right now, and although the 4x10 isn't exactly small, being a single cab on wheels it is much more manageable and we seem to have enough space for it in the vehicle when gigging. Even the 4-unit rack housing my Ampeg was just too cumbersome and heavy by comparison.

Is there anything I can do to see the full 500 watts with my usual cab setup?

Thanks!
 
#4
Such a device would literally cancel itself out.

You could put another 8 ohm huge resister in parallel with the cab, BUT.....

1) ....it would have to he a big one, and it would likely put off a lot of heat.

2) .... it would be cumbersome to rig up.

3) ....it would get you nowhere. If you have two 8 ohm loads on a 500W amp, each of them gets 250W. So you would be back to square one. The dummy resistor would get 250W and the cab would get 250W.
 
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#5
Selios said:
Hello,
With only 250 watts at 8 ohms I seem to be running the amp just about at its limit; it isn't struggling but I basically have nowhere to go in terms of volume against heavy drums.
Thanks!
Click to expand...
Why let the drummer dictate how much volume you need? Tell him to get some control over his playing and adjust his playing to the rest of the band, rather than the other way around. Good musicians actually do this.
 
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#6
byacey said:
Why let the drummer dictate how much volume you need? Tell him to get some control over his playing and adjust his playing to the rest of the band, rather than the other way around. Good musicians actually do this.
Click to expand...

We play with a wide range of dynamics, but that doesn't change the fact that the amp still runs out of headroom at our dynamic peaks, but thanks for insulting my drummer and close friend's musicianship anyway...

Thanks for the replies, it appears changing it up in the cabinet department is what I should look into.
 
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#7
If you somehow added something to cause the amp to “see” 4-ohms, rather than eight, the thing you added would receive half of the power. So, while your amp might produce more power, only half of it would reach the cabinet. That means you would have no more power, or volume, than you have now. The extra would just be wasted, so why bother?
 
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#8
Raf Seibert said:
If you somehow added something to cause the amp to “see” 4-ohms, rather than eight, the thing you added would receive half of the power. So, while your amp might produce more power, only half of it would reach the cabinet. That means you would have no more power, or volume, than you have now. The extra would just be wasted, so why bother?
Click to expand...

Just curious if there was a solution that met my interests. Thanks for the explanation.
 
#9
Selios said:
Thanks for the replies, it appears changing it up in the cabinet department is what I should look into.
Click to expand...

Considering you didn’t know the answer to your question, you probably shouldn’t look into this. Get a second 8 ohm cab, doesn’t matter what it is, and run it with your current cab. The more surface area the better.
If you don’t have PA support, you don’t necessarily need more watts, you need more surface area. Also if you can’t be heard over your drummer with a 410, it might be a drummer problem. Friend or not.
 
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#10
willsellout said:
Considering you didn’t know the answer to your question, you probably shouldn’t look into this. Get a second 8 ohm cab, doesn’t matter what it is, and run it with your current cab. The more surface area the better.
If you don’t have PA support, you don’t necessarily need more watts, you need more surface area. Also if you can’t be heard over your drummer with a 410, it might be a drummer problem. Friend or not.
Click to expand...

Yeesh. Getting another cabinet constitutes "changing it up" in my amp rig, doesn't it? And I already acknowledged it as a solution that I wanted to explore other potential options before choosing, given that options existed, which was all I was asking. I know my situation and the drummer is not the root of the problem I am trying to solve. The drummer's playing does not change the fact that the amp will clip with this 8 ohm cabinet before it is able to do full justice to the band's dynamics in some larger-room gigs with no bass in the PA, which we sometimes play. And thus I was curious about a potential solution that apparently isn't realistic.

Do we not ask questions on a public forum to assist with our own research, through which I've already clearly identified my other options in my OP?

Are you this blunt and condescending with your customers at Sweetwater, too?
 
Last edited:
#11
Selios said:
Hello,

Sorry if this has been asked before but I couldn't find anything helpful; is it possible to change the ohm load that your amp sees without adding more speakers or buying a cabinet that has a different resistance rating? Does such a device exist to make this happen?

I ask because I recently bought a Warwick LWA 500 micro amp that I really like, but my only cabinet (an 8 ohm 4x10) doesn't allow the amp to run at its full 500 watts. This amp's extremely small size and weight is an important factor to me (shoulder injury and space limitations when travelling with bandmates, merchandise, etc.), but I am used to having lots of headroom as I came from using a rack-mounted Ampeg SVT 5-Pro. With only 250 watts at 8 ohms I seem to be running the amp just about at its limit; it isn't struggling but I basically have nowhere to go in terms of volume against heavy drums. If I were ever to need to turn up the volume at a gig, the amp would be getting into clipping territory. It is well-documented on this forum that these Warwick amps do not sound good as soon as the clip light engages.

I would like to get the full power of the amp without either buying another 8 ohm cabinet or buying a 4 ohm cabinet. I don't have the budget for that right now, and although the 4x10 isn't exactly small, being a single cab on wheels it is much more manageable and we seem to have enough space for it in the vehicle when gigging. Even the 4-unit rack housing my Ampeg was just too cumbersome and heavy by comparison.

Is there anything I can do to see the full 500 watts with my usual cab setup?

Thanks!
Click to expand...

If this were possible, the difference between 250 and 500W would be barely perceptible (3dB). I know it's not what you want to hear, but adding a second identical speaker would get you 6dB more output in the low end since the power of your particular amp actually doubles.

Being as you don't have the cash to buy another cab or upgrade, I guess you need to make do with what you have. If the problem is you can't hear well enough, consider elevating the cab so it is closer to your ears. I toured professionally with an Eden D210XLT and one side of a power amp that made about 270W and it was plenty because we had a good PA that carried the bass to the audience. I elevated the cab and tilted back a bit to aim at my ears.

If the problem is you need to carry the house with your rig, and you are not quite loud enough; then the best solution is generally adding a cab if possible. The caveat is the cabs need to be reasonably efficient and it's generally best if the cabs are identical. Mixed cabs might work okay, but the results can be unpredictable.
 
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#12
Wasnex said:
If this were possible, the difference between 250 and 500W would be barely perceptible (3dB). I know it's not what you want to hear, but adding a second identical speaker would get you 6dB more output in the low end since the power of your particular amp actually doubles.

Being as you don't have the cash to buy another cab or upgrade, I guess you need to make do with what you have. If the problem is you can't hear well enough, consider elevating the cab so it is closer to your ears. I toured professionally with an Eden D210XLT and one side of a power amp that made about 270W and it was plenty because we had a good PA that carried the bass to the audience. I elevated the cab and tilted back a bit to aim at my ears.

If the problem is you need to carry the house with your rig, and you are not quite loud enough; then the best solution is generally adding a cab if possible. The caveat is the cabs need to be reasonably efficient and it's generally best if the cabs are identical. Mixed cabs might work okay, but the results can be unpredictable.
Click to expand...

Thank you for the constructive explanation!
 
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#14
I had the same issue in the past. If you don't want to add a cab, you could sell the 8 ohm and buy a 4 ohm cab. Another option would be to change the drivers to get the 4 ohm load. The problem with that is finding speakers with the same parameters as the originals. I chose to go for a 4 ohm cab that was also efficient. I went with an Epifani UL410 that is 4 ohms, handles 1000 watts and weighs 56 pounds. It is a light weight low end monster. Good luck!
 
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#17
Thumpin6string said:
I had the same issue in the past. If you don't want to add a cab, you could sell the 8 ohm and buy a 4 ohm cab. Another option would be to change the drivers to get the 4 ohm load. The problem with that is finding speakers with the same parameters as the originals. I chose to go for a 4 ohm cab that was also efficient. I went with an Epifani UL410 that is 4 ohms, handles 1000 watts and weighs 56 pounds. It is a light weight low end monster. Good luck!
Click to expand...

Actually, the UL410 might just be the ticket. They are ridiculously loud. They are very light. They are very well built. And you can often find them at GREAT deals. I got one for just over $300. I have an SVT with a 610 and a Mesa Walkabout Scout 15" combo with a matching extension cab. I consider both "big rigs". But I can also take out my Ashdown LB30 (30W tube head) and the UL410 and cover any stage those other rigs handle.
 
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#19
Selios said:
Yeesh. Getting another cabinet constitutes "changing it up" in my amp rig, doesn't it? And I already acknowledged it as a solution that I wanted to explore other potential options before choosing, given that options existed, which was all I was asking. I know my situation and the drummer is not the root of the problem I am trying to solve. The drummer's playing does not change the fact that the amp will clip with this 8 ohm cabinet before it is able to do full justice to the band's dynamics in some larger-room gigs with no bass in the PA, which we sometimes play. And thus I was curious about a potential solution that apparently isn't realistic.

Do we not ask questions on a public forum to assist with our own research, through which I've already clearly identified my other options in my OP?

Are you this blunt and condescending with your customers at Sweetwater, too?
Click to expand...

When I get questions like this, sometimes yes. For some reason people think just because I'm in customer service I have to treat everyone with kid gloves. In this line of work I make money with my time and my experience/knowledge. So it literally pays to cut to the chase, identify the problems, and find the right solution as quick as possible. In your case, the right solution is to get a second cabinet. Either that or get a stupidly efficient 4 ohm cabinet and hope that that works. I'd still stick with a second cabinet.
 
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