Power Amp Recommendations

[CL400Peavey]

In the sound reinforcement world, the 1.5-2x amp power: speaker power handling ratio is often used, because owing to the dynamic nature of music, average power to a speaker is much less than peak and speakers can indeed handle transient peaks well in excess of their rated power handling. Using a power amp rated for more power than the speaker it's driving allows a bit more transient headroom before amplifier clipping. This is perfectly reasonable and commonly done. It does mean you need to be judicious with how you operate things, though, because if you're running heavily compressed program material or the system limiters are clamping down hard, you clearly do run the risk of overpowering the drivers to the point of damage.

If you put more power in to a speaker than it can handle mechanically, or thermally, you will damage the speaker. There is no minimum required power to effectively run a speaker. One may prefer the tone of an amp pushed to a certain point, or the tone of a speaker as it goes in to nonlinearity, but those are not requirements.

 

[Mark Reccord]

Try again, 465w -> 600w is +1.3 db, barely noticeable.

You know, when I did the calculation I told myself to multiply by 10 but somehow still multiplied by 20. 1.1dB by my calculator if I use the correct factor.

 

[mbelue]

You know, when I did the calculation I told myself to multiply by 10 but somehow still multiplied by 20. 1.1dB by my calculator if I use the correct factor.

Yeah but I all want that 1.1db, dammit.
That 1.1db could save lives.

 

[s0c9]

To maximize output? WTH does that even mean? Underpowering isnt an issue. It doesnt exist.

If one isn't concerned about appropriately powering speakers, feel free to run that 600w cab with a 50w amp. See how well that's works.
Ergo: That will give you the answer to your obviously obtuse question.

 

[mbelue]

If one isn't concerned about appropriately powering speakers, feel free to run that 600w cab with a 50w amp. See how well that's works.
Ergo: That will give you the answer to your obviously obtuse question.

I regularly use a 20w amp with a 500w cab. Sounds fantastic.
I also use a 700w amp with it.
They both sound great and have their uses.
To what do you refer?

 

[CL400Peavey]

If one isn't concerned about appropriately powering speakers, feel free to run that 600w cab with a 50w amp. See how well that's works.
Ergo: That will give you the answer to your obviously obtuse question.

You can "appropriately" power a 600 watt cab with a 50 watt amp. You may meet the limitations of the amp, but that is some people's goal. There is not standard ratio of power required. There is no requirement.

 

[Mark Reccord]

If you put more power in to a speaker than it can handle mechanically, or thermally, you will damage the speaker. There is no minimum required power to effectively run a speaker. One may prefer the tone of an amp pushed to a certain point, or the tone of a speaker as it goes in to nonlinearity, but those are not requirements.

1. No argument but most damage is done by putting more average power into a drive than it can handle. You can easily exceed a driver's rated power on transients without exceeding it on an average basis, because music is dynamic. There is more of a worry of mechanical damage to LF drivers by transient peaks but by and large, systems can be operated with more potential amplifier power than speaker rated power without much issue, assuming a competent operator.

2. I don't think anyone has said that there is some minimum power needed to effectively run a speaker. I certainly didn't. What I am saying is that in an industry where it is important to be able to wring the most performance out of a speaker system, using a power amp rated above the speaker rating is a reasonable thing to do. It is nearly ubiquitous in pro audio.

 

[s0c9]

I regularly use a 20w amp with a 500w cab. Sounds fantastic.
I also use a 700w amp with it.
They both sound great and have their uses.
To what do you refer?

Are you getting 600w out of that cab, or 25w?

 

[mbelue]

Are you getting 600w out of that cab, or 25w?

Neither, I'm getting sound, sometimes even music.
Wattage is a great measurement of heat.

 

[SamJ]

Crossover distortion is a product of class B operation or improperly aligned class A/B. SS or Tube.

there is NO possibility of crossover distortion in a Class A amp, period.

http://www.audioholics.com/audio-amplifier/amplifier-classes


I think one thing we're doing here is not agreeing on what in fact IS distortion musically speaking .. While tube amps will distort as easily as solid state, the nature of the distortion (even vs odd order harmonic) is what makes the tube amp useful all the way to it's full power (and higher).

Frankly, this thread is beginning to smack of a never ending debate with deeply held political (or otherwise biased) views... I've linked a half dozen sources, ranging from Audio Engineers, Wikipedia, IEEE, and now Audiofile sites.. yes, everyone has a counterpoint that may or may not have kernels of truth..

Fact is my ear is the ultimate judge, and i've tried both... I had the money to buy some of the most expensive SS amps on the market with ratings above 1000W... I spent that money on a tube amp. I made my decision, the OP made his, and you've made yours.

Peace out.

 

[Mark Reccord]

If one isn't concerned about appropriately powering speakers, feel free to run that 600w cab with a 50w amp. See how well that's works.
Ergo: That will give you the answer to your obviously obtuse question.

On the flipside, this will work just fine assuming it gives you the sound you want at the level you require. It's clearly not optimizing the sheer SPL the cab could produce but it won't damage anything. Even under the hardest clipping, that 50W amp could only produce an absolute maximum of 100W which would be well within the cab's capabilities.

 

[mbelue]

there is NO possibility of crossover distortion in a Class A amp, period.

http://www.audioholics.com/audio-amplifier/amplifier-classes


I think one thing we're doing here is not agreeing on what in fact IS distortion musically speaking .. While tube amps will distort as easily as solid state, the nature of the distortion (even vs odd order harmonic) is what makes the tube amp useful all the way to it's full power (and higher).

Frankly, this thread is beginning to smack of a never ending debate with deeply held political (or otherwise biased) views... I've linked a half dozen sources, ranging from Audio Engineers, Wikipedia, IEEE, and now Audiofile sites.. yes, everyone has a counterpoint that may or may not have kernels of truth..

Fact is my ear is the ultimate judge, and i've tried both... I had the money to buy some of the most expensive SS amps on the market with ratings above 1000W... I spent that money on a tube amp. I made my decision, the OP made his, and you've made yours.

Peace out.

I'm not familiar with many class A bass amps. Certainly none in the wattage category this thread has concerned itself with.

 

[s0c9]

You can "appropriately" power a 600 watt cab with a 50 watt amp. You may meet the limitations of the amp, but that is some people's goal. There is not standard ratio of power required. There is no requirement.

Who said it was a "requirement"..?? oh wait.. you did!

Of course one can power a 600w cab with a 50w amp... but you are not running that speaker at rated power. And most will try to run beyond the amps limitations because it's not "loud" enough. Hence the 1.5-2x "recommendation"...

 

[CL400Peavey]

2. I don't think anyone has said that there is some minimum power needed to effectively run a speaker. I certainly didn't. What I am saying is that in an industry where it is important to be able to wring the most performance out of a speaker system, using a power amp rated above the speaker rating is a reasonable thing to do. It is nearly ubiquitous in pro audio.

That is exactly what another poster was saying. None of this is taking power compression, or the horsespit specs most manufacturers apply to their bass cabs. Most often the real world power handling is half of what is quoted.

Are you getting 600w out of that cab, or 25w?

Neither, cabs dont produce watts. They produce SPL.

 

[Mark Reccord]

That is exactly what another poster was saying. None of this is taking power compression, or the horsespit specs most manufacturers apply to their bass cabs. Most often the real world power handling is half of what is quoted.

I didn't get that from his original post, and I think what he's getting at is that a 50W amp into a cabinet rated for 600 isn't going to allow optimum SPL out of the system. I don't think he was making the traditional "underpowering" argument.

 

[mbelue]

I didn't get that from his original post, and I think what he's getting at is that a 50W amp into a cabinet rated for 600 isn't going to allow optimum SPL out of the system. I don't think he was making the traditional "underpowering" argument.

In my use case "optimum" is tube grind and low SPL.
Now we need to consult Webster's to see if "optimum" should be replaced with some other arbitrary criteria.

 

[CL400Peavey]

that would make the need for an amp to produce 750w - 1350w per channel, or if single cab somewhere in that range in bridged mode. Most SS amps will not run less than 4-Ohms bridged.


PS: I own QSC PLX, PLX2, GX.. Crown XLS, Xti and Yamaha P series amps.

Who said it was a "requirement"..?? oh wait.. you did!

You did.

Of course one can power a 600w cab with a 50w amp... but you are not running that speaker at rated power. And most will try to run beyond the amps limitations because it's not "loud" enough. Hence the 1.5-2x "recommendation"...

That is going to happen with any rig. Do you think you are more likely to have more issue with over powering a cab, or with meeting the limitations of your amp?

 

[s0c9]

Neither, cabs dont produce watts. They produce SPL.

Who knew?
Now you're deliberately splitting hairs as you know that wasn't what I was talking about..

I didn't get that from his original post, and I think what he's getting at is that a 50W amp into a cabinet rated for 600 isn't going to allow optimum SPL out of the system. I don't think he was making the traditional "underpowering" argument.

Correct.. I'm well aware of the 'traditional "underpowering" argument' and was not touching that with a barge pole.

 

[RoadRanger]

You know, when I did the calculation I told myself to multiply by 10 but somehow still multiplied by 20. 1.1dB by my calculator if I use the correct factor.

Darn them Dee Bees, sting yah every time . Yur right, 1.14 db. I musta zagged when I shoulda zigged . For those following along 1 db is considered the minimum a human can discern, 3db is about what one would call "significant" - a doubling of the power.

 

[s0c9]

You did.

err.. "make the need" does not = "requirement".. but OK.

That is going to happen with any rig. Do you think you are more likely to have more issue with over powering a cab, or with meeting the limitations of your amp?

That would depend on what one powers the OP's 600w cab with, now wouldn't it!