Interesting conversation about speakers and ohms

[Nephilymbass]

Probably the most used 10" speaker is the 32 ohm one in the Ampeg 810. They seem to stand up well. But they're wired for 4 ohms. Maybe if they were wired in two banks of 8 ohms, they wouldn't move as much and would last even longer.

The speakers I took out of my ampeg 410he were 32 also. The new speakers I had installed are 8 ohms. I guess we'll see how they do. I have to agree though. The 410he and ampeg 810 held up better than any other cabs I've had and they've been in trailers , the back of pickups and been pushed to the limits often.

 

[wideload]

Why would the impedance matter? I don't pretend to know much about speaker design, but I've got 4 ohm 10"s in my 210av's, and in over 4 years I've never creased them.

I think you're just not trying hard enough, Jimmy! Get in there and do some damage! (Oh, and can I have your gig after you get canned for being hella loud?)

 

[monsterthompson]

To get any realistic relationship, you'd need to know the global 4 ohm 10" and 8 ohm 10" speakers, and then the repair numbers for each. Then you could determine a failure rate.

I see more Toyotas at my local repair shop than Bugatti Veyrons. Buggatti must make more reliable cars

 

[monsterthompson]

Yep. Here's his sine.

That's an interesting angle to take on this.

 

[Nev375]

4 ohm cabs need more repairs because people are feeding them more wattage to 'get all the watts out of my amp'. Rather than people who are using 8ohm cabs either singly or in pairs.

Who knows, but this is the most plausible explanation.

 

[engedi1]

Do you really get more watts out of your amp with a 4 ohm cab? If you have a 4 ohm 4x10 and the exact same cab in the 8ohm version, it won't actually be louder than the 8ohm will it?

 

[JimmyM]

Do you really get more watts out of your amp with a 4 ohm cab? If you have a 4 ohm 4x10 and the exact same cab in the 8ohm version, it won't actually be louder than the 8ohm will it?

That all depends on how much your amp puts out at 4 ohms vs 8. SS amps generally put out like 2/3 to 1/2 at 8 ohms what they put out at 4. But in practical usage, that extra wattage, while giving you a bump in volume, isn't a particularly big bump in comparison, and it's more about headroom.

 

[engedi1]

That's what I was thinking. I currently am running only 1 cab which is a 4 Ohm. I have TONS of headroom with this setup as the amp is a GK 1001 RB and could easily drive an ampeg 8x10. 2 8 ohm cabs would be my preference and I'll get there someday.

 

[Crossedwires]

Actually, the repair man is correct to a point. I have been doing electronic repairs for just about 40 years now. A 4 Ohm speaker will allow more current to flow through it. A speaker has a coil of wire that sits inside a slot in the magnet at the base of the speaker. That wire being of less resistance will allow more current, more current more heat, more heat the more potential for the wires to burn up. Now as far as the speaker moving more causing creases, Yes if you apply a set amount of power to a 4 and 8 ohm speaker the 4 ohm will move more. As far as creasing, that would have to be a speaker design issue. A quality speaker should not crease because of movement. Now, if you apply more power than the speaker is rated for, yes you can blow the speaker apart and usually it will go on the outer edge of the speaker, but the usual reason for a speaker to crack or blow out around the edge is because of age and wear and tear. You can buy speaker re-cone kits and repair the speaker yourself saving a fair amount of cash.

 

[khutch]

Do you really get more watts out of your amp with a 4 ohm cab? If you have a 4 ohm 4x10 and the exact same cab in the 8ohm version, it won't actually be louder than the 8ohm will it?

It doesn't matter how loud it is. A 4 Ohm speaker will draw twice as much power from the amp as an 8 Ohm speaker would if both see the same terminal voltage and power amps tend to act like ideal voltage sources when they are not overloaded which means that careless users can more easily overload a 4 than an 8. So it is rather to be expected that 4 Ohm speakers will fail more often than 8 Ohm speakers when both are used in the wild by musicians who may not pay a lot of attention to power ratings. Some of the repair tech's reasoning is faulty but his observation about the failure rate could be correct. I assume that when you take your gear into a repair shop you are careful to choose one where the staff can at least count, right? If he can count then his comments about the number of failures he sees are probably accurate but he would also need to know the size of the 4 and 8 Ohm populations in his market area to calculate the failure rates and he is very unlikely to have that information.

 

[Arthur SX]

4 ohm cabs need more repairs because people are feeding them more wattage to 'get all the watts out of my amp'. Rather than people who are using 8ohm cabs either singly or in pairs.

This the "main Reason" but too little wattage can blow a speaker also.

 

[BigBobbyBass]

This the "main Reason" but too little wattage can blow a speaker also.

Are you being serious?

 

[JimmyM]

This the "main Reason" but too little wattage can blow a speaker also.

I've hooked up a 25w amp to my cab that takes 1200w before it blows. Number of speakers I've blown: 0.

Myth busted.

 

[engedi1]

This the "main Reason" but too little wattage can blow a speaker also.

This is my favorite bass myth.

 

[BassmanPaul]

too little wattage can blow a speaker also.

You're joking right??

Please, let's not go there!!

 

[Arthur SX]

I've hooked up a 25w amp to my cab that takes 1200w before it blows. Number of speakers I've blown: 0.

Myth busted.

Once an amp starts clipping it will produce a square wave that will in turn keep the speaker at a high wattage longer than it was designed for. In some cases the speaker can not rid it self of the excess heat and walla "um what happened" Be careful

 

[JimmyM]

Once an amp starts clipping it will produce a square wave that will in turn keep the speaker at a high wattage longer than it was designed for. In some cases the speaker can not rid it self of the excess heat and walla "um what happened" Be careful

If that were true, then you couldn't amplify guitars and basses with fuzz pedals or synthesizers.

 

[One Drop]

Where's that popped cone when you need it?

 

[B-string]

OMG here we go again, I would post a facepalm but, this one will have to do

 

[BurningSkies]

Do you really get more watts out of your amp with a 4 ohm cab? If you have a 4 ohm 4x10 and the exact same cab in the 8ohm version, it won't actually be louder than the 8ohm will it?

You will get more 'watts' out of your amp in most cases (unless it's an amp with an output transformer with multiple taps). Now, more watts doesn't mean more volume necessarily, but the bulk of guys who think they need to get 'all their watts' don't know that. They also don't know that even if the speaker could take all that extra power, it wouldn't mean appreciably increased volume due to the fact that the relation of wattage to volume isn't linear...they don't know that power compression will be an issue...they don't know that their speakers are rated for thermal handling rather than excursion (that thing that creases speakers)...