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Amplifier Comparison SpeakerPower SP2-12000 and Powersoft K20-DSP-Aesop

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Oh nice! This one totally caught me by surprise. A lot of good data to digest. I'll read it over a couple of times and sleep on it a bit.

 

One lesson learned though... if you really want to have a world-class bass system, you gotta have one of these in their system. For realz.

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Here are the drivers I'm using:

 

http://www.bcspeakers.com/products/lf-driver/21-0/21ipal

 

They have a DC resistance of 0.7ohm, and I also measured 0.7ohm with my meter.  

 

21ipal_zpsr6mdkfqi.png

 

 

 

In Josh's measurements of the Othorn cabinet with the 21sw152-4 (DC resistance of 3.3ohm), the impedance minimums are at about ~28hz and ~59hz

 

 

 

 

othorn%20impedance_zps0n8wdebb.png

 

28hz: 3.8ohm

59hz: 3.9ohm

 

 

 

21sw152-4 specs:

 

21sw152%20impedance_zpslznltdz5.png

 

 

Josh also tested the 21-IPAL in the Othorn cabinet and stated the impedance between 25-30hz to be ~1.1ohm.  

 

 

What mains? Do you have measurements of the current draw while playing a 29 Hz sine tone?

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What mains? Do you have measurements of the current draw while playing a 29 Hz sine tone?

 

Dedicated 240v 30A.

 

So the B&C specs of the driver combined with Josh's impedance measurements of the same driver in the same cabinet just don't do it for you huh?

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Thanks Mike. I would love to do this with some smaller, more affordable amps but the setup and all that for this was a real PITA. Not something I want to take on again any time soon.

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Yea I bet that wasn't a ton of fun, but very education nonetheless. I Think the real winner here is Brian who is offering up a world-class amp at a pretty darn respectable price-point.  Bottom line, you aren't going to get close to this performance which much else... I think K-20/sp12000/a-14K are basically the pinnacle for around here....  You are going to get a TON more out of these than you'll see out of a plastic behringer or even my little peavey and crest 7.5....I would love to see a single comparison of either against one of the big dogs though....

 

At least you know your house can withstand it though Josh! 

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Dedicated 240v 30A.

 

So the B&C specs of the driver combined with Josh's impedance measurements of the same driver in the same cabinet just don't do it for you huh?

 

If you're gonna cite an impedance minimum at 2 specific frequencies (that aren't from a measurement of the same driver in the same cabinet), and claim there is no problem from the amplifier at that impedance minimum, then you need to show that the amp has no problems at maximum output at those frequencies with measurements that verify the current draw and impedance.

 

When you play a soundtrack the impedance is the average of all the frequencies being played, it's not that the lowest impedance is dominant. Even if the amplifier somehow has unlimited current capability (which, of course, it doesn't), your mains limit the current draw.

 

So, no, the data presented so far doesn't do it for me. Hope that's OK.

 

Josh wrote:

 

The driver also presents a very low minimum impedance to the amplifier being a 1 ohm nominal driver with a dcr of 0.7ohm, but again the excessively strong motor increases the severity of the impedance peaks and the net result is a broader, more elevated "base" of the impedance peaks which increases the actual impedance seen by the amplifier system to be higher than would be seen with a driver of lesser efficiency.

 

 

And honestly Luke, if you're gonna continue to answer my Qs with irrelevant one-liners, I'm really not that interested in the data. :rolleyes:

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Yea I bet that wasn't a ton of fun, but very education nonetheless. I Think the real winner here is Brian who is offering up a world-class amp at a pretty darn respectable price-point.  Bottom line, you aren't going to get close to this performance which much else... I think K-20/sp12000/a-14K are basically the pinnacle for around here....  You are going to get a TON more out of these than you'll see out of a plastic behringer or even my little peavey and crest 7.5....I would love to see a single comparison of either against one of the big dogs though....

 

At least you know your house can withstand it though Josh! 

 

In reality, the mains is the final determinant for performance. Amplifiers aren't magic boxes. They can only work to the voltage and current limits provided. The long term output is definitely limited by volts * amps = watts. In a perfect world, if your mains can feed 120 volts into 4 ohms, the current draw is 30 amps and the watts is 3600.

 

Now, if you present a 1 ohm load, the volts drops to 30V with 30 amps current draw and 900 watts. Push for more and shut down occurs. We saw that at your GTG with the SP amp while playing ULF-centric source.

 

Any amp that can handle 30 amps is a great amp, but reality has to be a part of the conversation.

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900 watts? Why would that present more of an issue than 3600 watts at 4 ohms? I don't get it. If that were the case wouldn't you always want to wire for 8 ohms to max current draw (but with the most resistance?)

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If you're gonna cite an impedance minimum at 2 specific frequencies (that aren't from a measurement of the same driver in the same cabinet), and claim there is no problem from the amplifier at that impedance minimum, then you need to show that the amp has no problems at maximum output at those frequencies with measurements that verify the current draw and impedance.

 

When you play a soundtrack the impedance is the average of all the frequencies being played, it's not that the lowest impedance is dominant. Even if the amplifier somehow has unlimited current capability (which, of course, it doesn't), your mains limit the current draw.

 

So, no, the data presented so far doesn't do it for me. Hope that's OK.

 

Josh wrote:

 

 

And honestly Luke, if you're gonna continue to answer my Qs with irrelevant one-liners, I'm really not that interested in the data. :rolleyes:

 

My 8 and 6 year old had an argument with almost that exact same use of words.  

 

"If you're not going to let me play with your toys I won't want to play with them anyway!!"  

 

Josh measured the IPAL in the Othorn but didn't publish the results of any of it.  At the time B&C didn't want him to share any information at all about it, not even him sharing he had the drivers period.

 

He said the impedance minimums were at the same points.  

 

29-30hz is right where the lowest bass line for my favorite dubstep demo track is, and it basically holds that frequency for 2-3 seconds straight.  59-60hz is right in the wheelhouse for drum kicks.

 

It seemed obvious to Josh and Brian that the use of this particular driver would cause problems for a lot of amps, and Powersoft eve made an amplifier module just for this driver rated at 8000w into...you guessed it...1ohm.

 

I'm fine with it that you don't think I'm approaching 1ohm loads,  but it's up to you to prove I'm not if you're really that concerned about it.  

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In reality, the mains is the final determinant for performance. Amplifiers aren't magic boxes. They can only work to the voltage and current limits provided. The long term output is definitely limited by volts * amps = watts. In a perfect world, if your mains can feed 120 volts into 4 ohms, the current draw is 30 amps and the watts is 3600.

 

Your argument is stupid.  In so far as mains capability limits performance, supply voltage and amp efficiency will be major concerns.  The SP2 runs on 240V and is 90% efficient.  Put it on a 30 A circuit, and it can supply something like 5000W continuously without tripping the breaker.  Try doing that with a class AB design with ~60% efficiency (generous estimate) that runs on a 120V/30A supply where you'll run out of gas at a measly 1700 W.

 

How much does this really matter?  I imagine a lot of amps would overheat before too long with that kind of load.  The class D is dissipating something like 600W, which ain't bad, but still requires some serious fan action in a 1 or 2U chassis.  The class AB is dissipating more like 1150W.  Whew!  That's hot!

 

This is a stupid line of argument because the SP2 kicks butt in this category.  A more sensible argument is that long term output capabilities aren't that important because the biggest ULF demands typically occur in transients or very short passages.  Average thermal dissipation rates are much lower in these cases.  Better yet, circuit breakers allow far more current to pass than they are rated for as long as the draw doesn't last too long.  IIRC, a couple seconds at 2-3X rated load is not likely to cause a flip.

 

Lastly, to the extent that line sag matters, some amps cope with it better than others, and it is never the "final determinant" so long as the operator is capable of replacing the line with a shorter or fatter cable.

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My 8 and 6 year old had an argument with almost that exact same use of words.  

 

"If you're not going to let me play with your toys I won't want to play with them anyway!!"  

 

Josh measured the IPAL in the Othorn but didn't publish the results of any of it.  At the time B&C didn't want him to share any information at all about it, not even him sharing he had the drivers period.

 

He said the impedance minimums were at the same points.  

 

29-30hz is right where the lowest bass line for my favorite dubstep demo track is, and it basically holds that frequency for 2-3 seconds straight.  59-60hz is right in the wheelhouse for drum kicks.

 

I'm fine with it that you don't think I'm approaching 1ohm loads,  but it's up to you to prove I'm not if you're really that concerned about it.  

 

No need to get petty about this Luke, you've only been asked to verify your claim which is not out of the ordinary for these discussions.  If you haven't measured your system's voltage and current while playing your demo track then all you have is a theory, which is also fine with us. 

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900 watts? Why would that present more of an issue than 3600 watts at 4 ohms? I don't get it. If that were the case wouldn't you always want to wire for 8 ohms to max current draw (but with the most resistance?)

I like to shoot for most power but if you wire too low in impedance then you chance destruction of most amps (or protection circuits turning on).  Fortunately these amps have reliable protections in place so that too much current doesn't cause a catastrophic failure.  All amps produce a maximum voltage and current before overheating or exploding.  How much for both of these maximum values depends on the amp design and amplifiers like these are insanely fucking complicated in design. 

 

The only way to get a clear idea of what you're working with is by looking at the current and voltage at highest and lowest impedances of the reactive load with the amps at their maximum clean level.  Bus pumping aside, the ultimate test for these and any sub amp is for how they behave driving a reactive load at 20Hz and under.  This is hands down the most demanding scenario for an amp.  When comparing amplifiers and looking at only this, you pretty much have to start by comparing their looped frequency response and then with that as your reference point, compare their maximum unclipped levels (verified by a scope) and see what the deal is from there. 

 

Don't take me the wrong way Josh, I appreciate the thread and I know what a pain in the ass it was.  :)  

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The only way to get a clear idea of what you're working with is by looking at the current and voltage at highest and lowest impedances of the reactive load with the amps at their maximum clean level.  Bus pumping aside, the ultimate test for these and any sub amp is for how they behave driving a reactive load at 20Hz and under.  This is hands down the most demanding scenario for an amp.  When comparing amplifiers and looking at only this, you pretty much have to start by comparing their looped frequency response and then with that as your reference point, compare their maximum unclipped levels (verified by a scope) and see what the deal is from there. 

 

Don't take me the wrong way Josh, I appreciate the thread and I know what a pain in the ass it was.  :)  

 

 

 

Oscilloscopes and current/ voltage captures are cool but how do these behave when strapped to a bunch of speakers? That was the point of this to begin with. Let's get away from the test bench captures while driving resistors in a water tank and use a real world load with all of the complexity and possible nastiness of multiple, heavy coil, high inductance drivers driven really hard. FR traces at a volt are useful but no guarantee of maintaining their shape when the amp is asked for full output or when loaded with complex reactive loads. Now a FR at the onset of clipping with a very slow and taxing measurement would be nice, but no one provides those. I wanted to dispense with paper ratings of things like watts and see the bottom line of how each amp handled driving a set of subs when the throttle was mashed to the floor. I don't even care about how clean the amp is or at what point it gets dirty with this type of setup. With a finished system design you either have enough gear to stay out of clipping and keep it clean or not IMO. That kind of thing was not within the scope of this type of setup.

 

No doubt about it the sub 20Hz range is way more demanding on the amps and once things get down to 10Hz and below it is even worse.

The duty cycle is much higher simply because the waveforms are so long in duration and the impedance is the lowest so current is both high and demanded for longer amounts of time. I don't know how many people are really familiar with REW's signals, but a maximum length sweep set to a bandwidth of 2-120Hz or similar is vicious when dumped unfiltered from soundcard to amp to speaker. The 2-20Hz band takes what is probably the first 7 seconds or so and when the amp is being driven with an input signal that is a couple of dB beyond what would light the clip lights it is a rough test. Nothing in any movie soundtrack I've ever seen yet has the duration and sustained draw from the amp to compare. It's not as bad as just leaving a 5Hz sine wave on at clipping indefinitely, but it is worse than anything I've seen in music or movie content. The fact that both the amps produce as much juice as they did and are protected against blowing themselves up even when pushed to their limit with this type of <10Hz stuff was exactly what I want to see. I truly would worry about blowing some amplifiers if driven in this way. Try it at your own risk.

 

Also the CEA-2010 style bursts...I'd like to note for those reading along that they are 6.5 cycles so at 50Hz it is equivalent to 0.13 seconds. Not long at all, but comparable to a kick drum thump overall. However down at 20Hz it is 0.33 seconds duration and at 10Hz it is now 0.65 seconds. Not real long but it might as well be an eternity compared to some of the 1 cycle 1kHz signals used to produce the power ratings for many amplifiers so it is more demanding than the signals used by many manufacturers for their ratings. I would like for amplifier manufacturers to adopt a standard to provide burst ratings using these standardized signals at something like 10Hz, 31.5Hz, 100Hz, 1kHz and 16kHz.

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At least you know your house can withstand it though Josh! 

 

Sort of.

There are a few innocent bystanders that came of walls or vibrated off and fell. Lost a few light bulbs. Some rattles I don't think can ever be fully taken care of. It's just too much energy for that.

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Your argument is stupid.  In so far as mains capability limits performance, supply voltage and amp efficiency will be major concerns.  The SP2 runs on 240V and is 90% efficient.  Put it on a 30 A circuit, and it can supply something like 5000W continuously without tripping the breaker.  Try doing that with a class AB design with ~60% efficiency (generous estimate) that runs on a 120V/30A supply where you'll run out of gas at a measly 1700 W.

 

How much does this really matter?  I imagine a lot of amps would overheat before too long with that kind of load.  The class D is dissipating something like 600W, which ain't bad, but still requires some serious fan action in a 1 or 2U chassis.  The class AB is dissipating more like 1150W.  Whew!  That's hot!

 

This is a stupid line of argument because the SP2 kicks butt in this category.  A more sensible argument is that long term output capabilities aren't that important because the biggest ULF demands typically occur in transients or very short passages.  Average thermal dissipation rates are much lower in these cases.  Better yet, circuit breakers allow far more current to pass than they are rated for as long as the draw doesn't last too long.  IIRC, a couple seconds at 2-3X rated load is not likely to cause a flip.

 

Lastly, to the extent that line sag matters, some amps cope with it better than others, and it is never the "final determinant" so long as the operator is capable of replacing the line with a shorter or fatter cable.

 

"Your argument is stupid..."

 

What the fuck? Is this Luke using SME's account? :ph34r::lol:

 

Into a 0.7 ohm load, no amp delivers 5KW long term or any term on a 30A line, 120V or 240V. At 1 ohm, volts equal amps and 30A is the limit, long term. There may be a 10% safety factor long term in the breaker, not 500%. That was the point of my post. It's not an argument, it's math. The SP-2-8000 was not 240V, it is 120V. On a 30A dedicated line it repeatedly shut down into a nominal 2 ohm load per side using ULF-centric source.

 

Brian's test results claim 100% efficiency since the rated output equals the tested output, although no mention of the input signal are cited. Be that as it may, my beef with the test is that he has a 14KW amp (rated, in bridged mode into 4 ohms) and tests only a single channel whereas his SP amps are full bridge amps. The proper comparison is to bridge the amp being compared to, as Josh did.

 

Your post is bullshit. (Hey, that was fun. Now I know why you guys like to do it regularly.) If you have the amp, can you post the measurements and the measured frequency response, or is bullshit gonna be all we get here?

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No need to get petty about this Luke, you've only been asked to verify your claim which is not out of the ordinary for these discussions.  If you haven't measured your system's voltage and current while playing your demo track then all you have is a theory, which is also fine with us. 

 

After all that your dad dishes out on these boards, just look at his latest reply to SME a few minutes ago, he better be able to take a little back in return.  I'd say my response was very tame, heck even AVS safe, compared to a lot that gets said around here.

 

Are you saying that Josh measurements of the IPAL in the Othorn are just a theory?  B&C's specs and my measurement of the DCR are just theory?  Is it really that far out there to assume that when Josh measures a driver/cabinet combo to be ~1ohm from 25-30hz and some dubstep with near sine-wave like behavior in that same range would measure similarly?

 

I'd be happy to measure the voltage and current, but I'll need a better meter.  I have a Klein MM200 and it's the biggest piece of garbage I've ever owned.

 

Any suggestions for a decent meter?

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Great to see the effort put into this Josh.  Interesting and enlightening results.  My only point of contention is that neither amplifier were asked to work all that hard except for below ~15-16Hz.  Above 16Hz the highish DCR of the driver and in-box impedance leave more like a demanding 8 Ohm load than a 4 Ohm load the nominally dual 2 Ohm VC would suggest.  being familiar with the SpeakerPower amps they have no issue driving low impedances where eventually you simply run into current limits.  While I wouldn't bother with the huge hassle, testing again at 1/2 the 2 Ohm/4 Ohm test would have likely given more insight into long term power capabilities and behavior under high current.

 

While the alternate is somewhat torturous on most drivers, it's also important to consider with real drivers what the load looks like when you push the driver.  As you get much past 1/2-3/4 Xmax the impedance does in fact droop over much of the range as the BL curve sags.  Take any driver model and now change the BL to 50-80% of the small signal parameters to see the worst cases a driver can present to the amplifier.  That big impedance peak on some sealed boxes droops greatly.  Drivers without shorting rings will also see modulation of BL in reflex and horn designs when you have high current at excursion minimums.  Coils will start to heat up some and DCR will rise, but even this comes with a loss in BL.  For dynamic home theater content, driver excursion and current through the coil are more common concerns.  This isn't to minimize the test results, but rather to highlight that for certain drivers and alignments, the lower impedance performance can become even more important than it might appear at first glance.

 

This is a stupid line of argument because the SP2 kicks butt in this category.  A more sensible argument is that long term output capabilities aren't that important because the biggest ULF demands typically occur in transients or very short passages.  Average thermal dissipation rates are much lower in these cases.  Better yet, circuit breakers allow far more current to pass than they are rated for as long as the draw doesn't last too long.  IIRC, a couple seconds at 2-3X rated load is not likely to cause a flip.

 

Lastly, to the extent that line sag matters, some amps cope with it better than others, and it is never the "final determinant" so long as the operator is capable of replacing the line with a shorter or fatter cable.

 

One bit Brian hasn't advertised much is the benefit of the more expensive power supply in the 6000W (& 3200W) amplifier optimized for 208-240V operation.  While the power supply functions on any power line over ~100VAC, there is a reduction in power somewhere below 185-200VAC vs the rating or vs the 4000W amplifier.  The benefit of what happens above that 185-200V range is often overlooked.

 

For any power line Voltage above 200V, the amplifier can deliver full rated power with no sagging of the rail Voltage.  No more power is had from a 240V line vs a 208V line.  For most users this provides a 10-20% line regulation where the line has to sag below ~200V before you see any loss in rail Voltage and power delivery.  For those pushing many subwoofers at high current, this can be a noticeable benefit over the 4000W amplifiers where I had one off-the-charts customer benefit greatly in powering 4 dual 18" vented cabinets.  Part of the benefit comes from lower line losses on a high Voltage line, and then if the line does sag, the amplifier has a good deal of immunity.

 

No amplifier is the perfect solution, as they all still need to pull the power from the wall and the cost can creep up quickly searching for ever more output, but when you consider the ability to run predominantly without a fan, and be nearly bulletproof into any low impedance, the SpeakerPower torpedo family of amplifiers deliver quite a bit for the money spent.

 

-Mark

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Yep yep. Agreed on your points Mark.

That's why I posted the impedance curve.  I would disagree a bit. Not with anything in general only that while the DCR is indeed a bit high-ish, I'd contend this is normal use driving speakers. Impedance fluctuates greatly with frequency and current is only high near the minimums. Unfiltered sealed systems are about the worst case. They only have one impedance peak and the amplifier is asked to produce high current into the impedance minimums in the lowest frequencies. Typical use for higher order systems means generally higher impedances, more impedance peaks and a low end that is filtered away in order to protect the drivers. Sure I could get some drivers with the DCR a bit lower down near 2.8-3 ohms for a 4ohm load but they will also typically have much higher motor force than the boat anchors used so the impedance peak will be much more severe and cover a broader plateau raising the average impedance over a large area of the bandwidth. I'd expect more current only required in the very deepest bass and perhaps at a narrow band above the resonance.

 

 I know you probably have at some point, but I doubt many others will have looked at actual average power applied to the speakers using even what is considered "intensive" content, over a significant amount of time like 30 minutes or an hour.  Even 400w average applied power to a subwoofer over more than a few minutes is a lot for the reasons discussed above. There are huge peaks in the content but the duration and overall average power is actually much lower than most people would assume.

 

I almost went with the SP amps. I didn't because of the whole GP testing thing and also because when the Euro went into the trash for a while I got a smoking deal on the K's. I needed the most amp I could get on one set of terminals and the SP can only use one side so that kind of clenched it. Kind of wish I did for the HT just because either amp has all the power needed but the SP fans are silent. Anyway this wasn't really meant to be a tediously detailed comparison but something different and fun. I still need to do some testing on the Ipal 21's so I may just go ahead and take both amps outside and let them both have a shot into 1 ohm and 2ohm minimums. I definitely want to use the 12K on the single 21 because that truly dips to 1ohm in spots and I don't think bridging the K20 into that will result in its best performance.

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Oscilloscopes and current/ voltage captures are cool but how do these behave when strapped to a bunch of speakers? That was the point of this to begin with. Let's get away from the test bench captures while driving resistors in a water tank and use a real world load with all of the complexity and possible nastiness of multiple, heavy coil, high inductance drivers driven really hard. FR traces at a volt are useful but no guarantee of maintaining their shape when the amp is asked for full output or when loaded with complex reactive loads.  I don't even care about how clean the amp is or at what point it gets dirty with this type of setup.

 

I wrote this in the above post: "The only way to get a clear idea of what you're working with is by looking at the current and voltage at highest and lowest impedances of the reactive load with the amps at their maximum clean level."

 

I didn't say that you should have used water heater elements.  Your test was interesting because you were beating the utter fuck out of the amps with hardcore drivers as the load and we learned that they will both go into protection mode in certain conditions as opposed to melting.  You are still left guessing when it comes to which amp put out an undistorted signal at a higher level, whether the amp's clip lights are accurate and where the mute limits are, or where their limits are at 10Hz and below.  Voltage and current measurement tools can help to show a clear picture of amplifier limits. 

 

My comment about volts and current is there for folks that might not know anything about amp testing, it wasn't aimed at you.  You post plenty of good data about drivers already, I wouldn't expect you to go all out for 1 amp comparison. 

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Are you saying that Josh measurements of the IPAL in the Othorn are just a theory?

Oh, I didn't know Josh started using Skrillex songs for driver data.  My mistake, nevermind. 

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Your test was interesting because you were beating the utter fuck out of the amps with hardcore drivers as the load and we learned that they will both go into protection mode in certain conditions as opposed to melting.  You are still left guessing when it comes to which amp put out an undistorted signal at a higher level, whether the amp's clip lights are accurate and where the mute limits are, or where their limits are at 10Hz and below.  Voltage and current measurement tools can help to show a clear picture of amplifier limits. 

 

We may not know the measured current and voltage limits for either amp over certain frequency ranges but I don't know of that type of data from other amps to compare to anyway.All of those tests cut off at 20Hz if they even go that low. I can get that data from the K20. It tracks the output voltage and current, the impedance of the load, average power, temperature in the amp, rail voltage, AC line voltage, blah, blah. Likewise it also shows when limiting occurs whether current or voltage and clipping in real time. The SP-12K doesn't have all of that so you would need a test rig to gather the data and of course we don't know whether the clip lights occur well before or well after actual clipping but I'd say it is fairly accurate at indicating that the amp is out of "more" since the output would plateau. No idea what the distortion is at that point.

 

We do know how these amps compare to each other at least in a limited sense. The K20 puts out more clean signal. It should based on the specs and that is what all of the tests showed. (As long as it is bridged for the sub 20Hz range of course.) The SP-12K might possibly put out more into very low impedance loads with sustained signals, which is also what the results showed. It seems to be allowed to pass a bit more current for longer. The K series is limited to 32A long term and claims like 125A peak short term ( I believe the indefinite limit is capped at around 4Kw). Both could probably pass more for a longer time but there has to be a limit to avoid tripping breakers which is a bad day all around at the gig. There's a limit to how much heat can be dissipated as well even with 90% or better efficiency. After bridging the K20 it did not protect during any of the tests. Perhaps bridging it into a lower impedance like 2ohms mono would cause it. I'll probably end up trying it. The SP-12K did mute with <10Hz if slammed into clipping. I don't mean approaching clipping I mean get to the point the clip lights are flashing and then give the volume knob another spin. Other than that it was fine with everything else too. Would be interesting to see the behavior at 1ohm minimums.

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I don't know how many people are really familiar with REW's signals, but a maximum length sweep set to a bandwidth of 2-120Hz or similar is vicious when dumped unfiltered from soundcard to amp to speaker. The 2-20Hz band takes what is probably the first 7 seconds or so and when the amp is being driven with an input signal that is a couple of dB beyond what would light the clip lights it is a rough test. Nothing in any movie soundtrack I've ever seen yet has the duration and sustained draw from the amp to compare.

 

Hollywood, you have heard the challenge...get to work.

 

JSS

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No amplifier is the perfect solution, as they all still need to pull the power from the wall and the cost can creep up quickly searching for ever more output, but when you consider the ability to run predominantly without a fan, and be nearly bulletproof into any low impedance, the SpeakerPower torpedo family of amplifiers deliver quite a bit for the money spent.

 

-Mark

 

I agree with this, except for the <1 ohm stuff. Really all that needs to be said.

 

 

I needed the most amp I could get on one set of terminals and the SP can only use one side so that kind of clenched it.

 

That's what I'm sayin'. The best you get with SP is a 6KW bridged amp. Adding multiples... can be done with any bridgeable or full bridge monoblock amp, and <1 ohm operation... not much relevance to HT or any audio scenario, actually.

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