How much power can a Peavey 115 BX BW handle?

[Diesel Kilgore]

The specs for the Peavey are 350 watts continuous and 700 peak.

I am trying to pair a new amp for this cab. I am thinking 200 watts will be plenty for what I need. But im curious what the cab could realistically handle? I feel like maybe I could get a higher output amp so I could have more power in reserve and not limit myself for those "just in case" moments.

[LarryO]

Is this a trick or are you having a multi personality conversation ?

[Diesel Kilgore]

Multi personality it must be.

[LarryO]

The reason I ask is because you answered your own question

[Diesel Kilgore]

200 watts? Or 350? Forgive my ignorance.

[dmusic148]

200 is in the right ballpark. Can't really go by thermal rating. That's how people break things.

[Diesel Kilgore]

Ok cool. What is the thermal rate, the 700 peak rating?

[dmusic148]

No, the 350 number is the thermal. 700 peak. Trouble is thermal numbers are never realistic for our application. Always de-rate a bit from the thermal spec and you'll usually be OK.
Main thing is to listen to what the speaker is telling you. If you overpower it, it'll tell you it's unhappy and you'll have a chance to do something about it before harm is done.

[warnergt]

Originally Posted by dmusic148

...Always de-rate a bit from the thermal spec and you'll usually be OK...

True, but de-rating is also a good idea when choosing an amp.
I'd rather run a 400 watt amp at half power than a 200 watt
amp at full power.

[dmusic148]

Originally Posted by warnergt

True, but de-rating is also a good idea when choosing an amp.
I'd rather run a 400 watt amp at half power than a 200 watt
amp at full power.

Sure. Unless you really liked the sound of the amp cranked. Like a GK400 or 800RB. Great sound cranked.

[Diesel Kilgore]

Originally Posted by warnergt

True, but de-rating is also a good idea when choosing an amp.
I'd rather run a 400 watt amp at half power than a 200 watt
amp at full power.

This was another concern of mine. The GK MB200 looks great, but do I want to run it at its peak all of the time? Maybe it would be a good idea to get another 100 watts to have a cushion?

[dmusic148]

The MB200 appears to be a very nice unit, but I have no experience with it.
Enough? I would venture to say it depends on whether your cab is the 4 or 8 Ohm model. Teeny micros, in my experience work better when run at their minimum impedance.
It may sound/feel a bit 'soft' pushing an 8 Ohm box, in a band context.
In that case I'd shoot for one of the 500 watt@4 Ohm micros, such as a Little Mark III or similar.

[will33]

Can go with a little extra power if you want a clean loud, headroom, though the GK amps get a nice musical growl when run up toward their limits. I've been using a 400RB lately and like being able to crank it without getting too loud.

As for the speaker, it depends a lot on the cab design. My 1505 Widows reach their stated xmax at anywhere between 160 and 200 watts depending on the cab design. Think of xmax as "relatively clean" bass, or just reaching the verge of audible distorton. As far as thermal ratings, power compression is going to come into play over the course of a gig. If you knock 2 or 3 db off the top to account for that, the thermal rating of most common speakers come more in line with their mechanical ratings.

What all that means is, 200 watts will pretty much make that speaker do what it's going to do. 400 watts will give you a margin of clean headroom. More than that is likely a waste of money unless you plan on adding another cab to the stack in the future.

[dmusic148]

Originally Posted by will33

What all that means is, 200 watts will pretty much make that speaker do what it's going to do.

Sure. But the question is will the MB200 deliver? I'm saying that if the cab is an 8 Ohm unit -- probably not.

[BogeyBass]

Having a little overhead is nice wattage wise.

But the speaker is going to start to break up way before 350watts

its just a single 15 and all of them reach the limit way way way before the thermal limit.
so their is only a max amount of "volume" or sound pressure level your going to get before speaker distortion.

so it really not a issue of "having enough watts" it more a issue of "Having enough speaker"
so if you are not able to reach the level you need in your band. You dont need more wattage you need more speaker. another matching 15" in this case

the real world power handling for that speaker is around 90 to 130 watts most likely on the lower side.
so a pair would be good for 200 to 260 watts. this is far below the 350watt rating of the amp.

so yes 350 watts is plenty of power it will give you 100watts of overhead before you hit the distortion of the speaker system.

but im guessing 350 watts is the overrated 4ohm rating
so its most likely a typical 200watt amp. and how spongy that 200 watts is i dont know.

[Diesel Kilgore]

The cab is 8ohm.

[will33]

Originally Posted by dmusic148

Sure. But the question is will the MB200 deliver? I'm saying that if the cab is an 8 Ohm unit -- probably not.

It might not. They're what, 140 or something on 8ohms?

Also pretty hard to get an amp to even run full out aside from the occasional peaks.

[BogeyBass]

Originally Posted by dmusic148

Sure. But the question is will the MB200 deliver? I'm saying that if the cab is an 8 Ohm unit -- probably not.

but again dont confuse him now this makes people think they need a 4ohm single 15 to " Get more power out of the head"

as said the speaker cant do more than 90 to 130 watts so more power is not needed. just need more speaker.

in the end you will need more speaker. and you want to stay with 8ohms. because a pair is going to be 4ohms (2x8ohms)
and most average amps these days are only stable at 4ohms.

all in all that is why its better to look for 2ohm stable amps.
so your able to add more speakers and not overheat the amp.

even if you only run at 4ohms a 2ohm stable amp is going to be tougher and more robust. its designed to dissipate more heat.
and being able to dissipate more heat is what makes a amp 2ohm stable.

[dmusic148]

Originally Posted by BogeyBass

but again dont confuse him now this makes people think they need a 4ohm single 15 to " Get more power out of the head"

I understand. Not trying to do that.
Point is, he's apparently settled on the cab he has. His original question was "How much power will it handle." I'm saying about 200 watts.
And I'm saying that a 200 watt/4 Ohm micro will probably fail to exploit the potential of that particular cab at 8 Ohms, and be disappointing.
A larger head will work better, without stressing the cab.

[will33]

Originally Posted by BogeyBass

but again dont confuse him now this makes people think they need a 4ohm single 15 to " Get more power out of the head"

as said the speaker cant do more than 90 to 130 watts so more power is not needed. just need more speaker.

in the end you will need more speaker. and you want to stay with 8ohms. because a pair is going to be 4ohms (2x8ohms)
and most average amps these days are only stable at 4ohms.

all in all that is why its better to look for 2ohm stable amps.
so your able to add more speakers and not overheat the amp.

even if you only run at 4ohms a 2ohm stable amp is going to be tougher and more robust. its designed to dissipate more heat.
and being able to dissipate more heat is what makes a amp 2ohm stable.

I don't know which model of Widow is in his cab. My 1505's with xmax of 4.8-5mm model north of 160watts. That seems about right just off my highly unscientific method of pummelling them with powerful amps.. Coupled with high sensitivity, they make a lotta noise.

If it has a KADT in there, those have almost no xmax and are midbass/mids made for stacking between bass bins and HF horns.

The 1502's xmax is more like 2.8-3mm. Those do get grindy. Some like it, some don't.

I don't have any first hand experience with the newer 1508's.

So, knowing just which model of Widow he has in there would go a long way towards figuring this out. They can vary greatly and if it's a used cab or has ever had the driver replaced, or even re-basketed to a different model, could throw a wrench in the works as well.