Bestow upon me you amp wisdom

[bobostein]

A few amp questions that have been lurking in my mind.
1. Will 200watts @ 4ohms be louder than 200watts @ 8ohms?
2. Will a 410 with a 800watt power rating be louder than a 410 with a 400watt power rating when the same amount of power was used on both, lets say 200watts?
3. Is there a sound difference if a cab is on feet/casters vs. just the bottom of the cab on the floor/stage?

[oinkbanana]

2. all things being equal - no difference. what makes a difference is your speaker efficiency, this is rated something like 96db @ 1 watt. if both speakers have all things equal except for max power rating, then the higher rated speaker can get louder at the higher wattage. at teh same watts, they should both put out the same volume.

3. yes it'll sound different.. with more of your cab is touching with the stage, more frequencies can be transferred to the stage to vibrate the stage. this is called coupling.

i'm not answering no.1 because it's probably impossible to have all things equal except the ohms. even your amp will act differently to different Ohms. but in an ideal theoretical situation there would be no difference. :duck:

[StuartV]

1) Possibly, but not enough to notice.

2) A 410 with a higher sensitivity rating will be louder than one with a lower sensitivity rating, when you input the same amount of power. Their impedance (ohm rating) is pretty irrelevant.

3) There can be. Or there can not be. Mostly depends on the floor, I think.

[Zoa]

1) Possibly, but not enough to make a difference.

2) Maybe, but not because of the power handling spec, which is probably garbage anyway.

3) Depends.

[bobostein]

Thanx everyone

[billfitzmaurice]

Originally Posted by bobostein

A few amp questions that have been lurking in my mind.
1. Will 200watts @ 4ohms be louder than 200watts @ 8ohms?

No. Loudness isn't measured in watts, nor does the power output have any direct relationship with what loudness is measured in, decibels.

2. Will a 410 with a 800watt power rating be louder than a 410 with a 400watt power rating when the same amount of power was used on both, lets say 200watts?

Again, the power rating has no direct relationship with how loud a cab plays.

3. Is there a sound difference if a cab is on feet/casters vs. just the bottom of the cab on the floor/stage?

No, not unless the feet/casters lift the cab at least a foot or so.

[Marty Forrer]

3. If the stage is hollow and resonant, it can often be beneficial to have the cab on castors, or better yet, on rubber feet. This will help minimise the boom and vibration that many stages have.