500W head into 100W cab?

[dubstyle]

I have recently purchased the new Ampeg Portaflex 500 watt head, which should be arriving soon.

I currently play through a Hartke A100 solid-state combo amp. It's a great little thing, very versatile and surprisingly powerful.

I plan on selling the Hartke and, when I scrape together the money, buying the Ampeg PF-210HE cab to match the head, so I can utilise the fliptop function (and the extra power of course).

The Ampeg head is 500W @ 4 ohms
The Hartke cab is 100W @ 8 ohms

Will it be alright to run the Ampeg head through the Hartke cab? Or will I blow the speakers? I won't be cranking the volume too ridiculously high.

This is my first post, so please tell me if I've posted this in the wrong section...
Thanks guys

[Downunderwonder]

You'll have to be strongwilled to keep the volume in bounds. 2000W is fine if you are careful.

[seamonkey]

You can't run 500w into a cabinet rated 100w or you will blow the speaker.
Plug it in with the volume all the way down and don't turn the knob past 100w and you'll be fine.


Tips - if the cab farts turn it down. Don't expect a lot of volume.

[Downunderwonder]

Forgot to mention, but in the light of that other thread asking if he can plug his backup amp into his cab at the same time as his other amp:

UNPLUG THE COMBO AMP FROM ITS SPEAKER!!!!

unless you want to blow up both amps.

[Electricblue]

Originally Posted by seamonkey

You can't run 500w into a cabinet rated 100w or you will blow the speaker.
Plug it in with the volume all the way down and don't turn the knob past 100w and you'll be fine.


Tips - if the cab farts turn it down. Don't expect a lot of volume.

My volume knob measures in watts too...

[4-string]

Originally Posted by seamonkey

You can't run 500w into a cabinet rated 100w or you will blow the speaker.
Plug it in with the volume all the way down and don't turn the knob past 100w and you'll be fine.

This is bad advice. Volume all the way down and you are seriously underpowering your cab.



Common sense and back off a little if the cab starts to fart out, you'll be fine.

[Electricblue]

Originally Posted by 4-string

This is bad advice. Volume all the way down and you are seriously underpowering your cab.



Common sense and back off a little if the cab starts to fart out, you'll be fine.

I do hope you are joking

The maximum you can turn it up, is the moment when you hear farts/buzzing from your cab.

You could roll off the lows on your amp to get a bit more room.

[dubstyle]

Originally Posted by Electricblue

The maximum you can turn it up, is the moment when you hear farts/buzzing from your cab.

You could roll off the lows on your amp to get a bit more room.

Along with, obviously, the volume, there's a bass and treble knob on the Hartke that I could back off a little with. But there's also a limiter. Any idea if I could utilise that to ensure nothing explodes?

[jondog]

Originally Posted by dubstyle

I have recently purchased the new Ampeg Portaflex 500 watt head, which should be arriving soon.

I currently play through a Hartke A100 solid-state combo amp. It's a great little thing, very versatile and surprisingly powerful.

I plan on selling the Hartke and, when I scrape together the money, buying the Ampeg PF-210HE cab to match the head, so I can utilise the fliptop function (and the extra power of course).

The Ampeg head is 500W @ 4 ohms
The Hartke cab is 100W @ 8 ohms

Will it be alright to run the Ampeg head through the Hartke cab? Or will I blow the speakers? I won't be cranking the volume too ridiculously high.

This is my first post, so please tell me if I've posted this in the wrong section...
Thanks guys

You don't have a Hartke cab. You have a Hartke combo amp. You cannot run the speaker out from the Ampeg into the Hartke combo input without destroying something. You can run the Ampeg line out into the Hartke, Or, if you can figure out how to bypass the Hartke head and go directly to the speaker you can use the Ampeg speaker out.

[Downunderwonder]

Yeah, I sent him a PM too, just in case.

[dubstyle]

Originally Posted by jondog

You don't have a Hartke cab. You have a Hartke combo amp. You cannot run the speaker out from the Ampeg into the Hartke combo input without destroying something. You can run the Ampeg line out into the Hartke, Or, if you can figure out how to bypass the Hartke head and go directly to the speaker you can use the Ampeg speaker out.

My post might have been poorly explained: on the combo, there is an instrument cable coming out from the speaker (hardwired I presume) and into the amplifier, marked 'speaker out'. I was thinking of plugging that cable into the back of the new Ampeg head. The wire is coming straight from the speaker itself. Bad idea? Or is it ok? I am bypassing the amplifier part of the combo all together.

[dincz]

Originally Posted by dubstyle

My post might have been poorly explained: on the combo, there is an instrument cable coming out from the speaker (hardwired I presume) and into the amplifier, marked 'speaker out'. I was thinking of plugging that cable into the back of the new Ampeg head. The wire is coming straight from the speaker itself. Bad idea? Or is it ok? I am bypassing the amplifier part of the combo all together.

You can do that. Just be careful with the volume. Your head will only give around 300W max into an 8 ohm speaker so there's room for overpowering but not as much as the 500W (into 4 ohms) rating would suggest.

[Edward G.]

The speaker itself determines how loud it can be. If the speaker sounds like it is being over-taxed, then you are applying too much power to it. Period. That's why we have volume controls.

Nominal power ratings are largely meaningless for amps and speaker cabinets. There are no perfect matches, either, just better and worse ones that are ALWAYS subjective. Resistance ratings are far more absolute.

As usual, there is no substitute for common sense. If you cannot tell when a speaker is faltering under too much power (or too little clean power), it is possible your horse sense is what is lacking.

[MuzikMan]

You'll be fine just as others have said. I used to run a 900 watt power amp into a 200 watt Hartke cab and never had any issues. Just use common sense and listen to your cab, it will let you know when you are at your limits.

[billfitzmaurice]

[quote=dubstyle;10805007]

This is my first post, so please tell me if I've posted this in the wrong section...

No, but you could have saved a lot of bandwidth by reading this before making it:
AMPS FAQ!! Info on OHMS, Allsize RIGS-OverUnderPowerCabs DIY TechTalk-Links

[dubstyle]

[quote=billfitzmaurice;10805695]

Originally Posted by dubstyle

No, but you could have saved a lot of bandwidth by reading this before making it:
AMPS FAQ!! Info on OHMS, Allsize RIGS-OverUnderPowerCabs DIY TechTalk-Links

Thanks very much, reading over some of it now, very useful

[Downunderwonder]

It's not an instrument cable, it's a speaker cable. There is a difference. But if it's long enough to reach your new amp and the new amp has 1/4" outputs then you are good to go.

[chunkstyle]

i bet right before all hell breaks loose, it'll sound killer.


actually, like someone else said it'll be about 300 watts into that 8 ohm load so you probably won't have to worry about magnet shrapnel... wait, is it an aluminum cone?

[brother21]

Originally Posted by dubstyle

I have recently purchased the new Ampeg Portaflex 500 watt head, which should be arriving soon.

I currently play through a Hartke A100 solid-state combo amp. It's a great little thing, very versatile and surprisingly powerful.

I plan on selling the Hartke and, when I scrape together the money, buying the Ampeg PF-210HE cab to match the head, so I can utilise the fliptop function (and the extra power of course).

The Ampeg head is 500W @ 4 ohms
The Hartke cab is 100W @ 8 ohms

Will it be alright to run the Ampeg head through the Hartke cab? Or will I blow the speakers? I won't be cranking the volume too ridiculously high.

This is my first post, so please tell me if I've posted this in the wrong section...
Thanks guys

You would be sending 250 watts at that 8ohm cab 100 watt cabinet not 500 watts

I say thats a good loud setup & you could play gigs anywhere

[dubstyle]

Originally Posted by chunkstyle

i bet right before all hell breaks loose, it'll sound killer.


actually, like someone else said it'll be about 300 watts into that 8 ohm load so you probably won't have to worry about magnet shrapnel... wait, is it an aluminum cone?

Yes, I'm fairly sure it is an aluminum cone...