Upgraded Amps & Drivers, Huge Output
The below text is a transcription of the video.
Hey there, John Hunter with REL here, and we’re back. So some people want to know how are we getting anywhere from 50 to 100 percent more output out of our new HT/MKII’s. This is insanity, right? We’re getting 6 dB more out of the 1205, we’re getting over 10 dB more, which is a doubling of perceived output out of the new HT 1003 MKII, it is playing as loud as things that cost well over $1,000. In the case of this piece, it’s frankly louder than most things that are up to $2,000. So what is going on? Because the driver’s size hasn’t changed and the power amplifier rating hasn’t changed. Two things. Three. The driver’s a little more efficient in both cases. It’s a better built driver that’s got lots more stroke available to it. It’s just a better overall driver with a little bit more efficiency. That doesn’t explain it.
The amplifier, on the other hand, is a much bigger, much better built amplifier. So this is a 500 watt amplifier that I have no doubt we could certify at 600 watts continuous. It’s a bigger beefier, better amplifier. We got better. We made amps better. And we found along the way that we were doing it, that doing this didn’t have to cost a lot more. We simply went after every little tiny detail and refined it out and got more out of the amps. So we got more out of the amp, more out of the driver, and then we got more out of ourselves. So every amplifier worth a darn has something called a limiter in a subwoofer. The limiter is there as essentially a safety precaution. What we don’t want you to do is accidentally play something too loud and have the amplifier destroyed because the incoming signal was so massive that the amplifier was asked to do far more than it’s rated for.
And the net result is first you blow up the driver, then you blow up the amplifier because the driver blew up. So our limiters are, I think a little different than most, and they’re very progressive. We have three stages to our limiters. You can think of it a small, medium and large. The largest sort of the action of last result. It’s a bit like playing a musical instrument. These are not intuitive, easy. Well, you just plug a certain amount of voltage in, measure what you got, boom, you’re done. You can’t do that because we’re not dealing with sine waves. We’re not dealing with the easy predictability of, well, we’re on a test bench. We’ll just put a tone in, we’ll measure what we’re getting out. No problem. Big problem. The biggest jump above zero we’ve seen when we actually measure the amount of output from the LFE output, the low frequency effects channel in movies is 19 decibels above zero. Holy smokes. It’s a huge amount of power needed to do that. And it’s instantaneous. If it’s a hand grenade, if it’s a shotgun, if it’s a bomb blast, all of those things happen instantly. Five picosecond kind of range. Boom. And it suddenly goes from normal dialogue levels like this to 19 decibels above that. That’s easily four times the volume needed. The power that’s needed would be squared, 16 times as much power boom, that’s a problem. So we’ve been able to, with our latest round of limiters on these new amps, we’ve been able to figure out how to titrate those dynamic events such that we’re able to get almost all the rated power out any maybe a little bit more without running hard into the limiter, without sort of stopping everything, shutting down the production, having the amplifier go quiet for 10 seconds while it goes, what just happened to me?
Alright. So that’s really the secret is the musicianship, if you will, the ability to go in, understand our circuits, get the very most out of each one of those three stages, get it all the way out to the 500 plus watts that this amplifier can put out, get it all the way out to the very limits of the 300, where in previous generations we would had to begin limiting them significantly earlier and having an even softer, more progressive limiting action. We’re learning how to make them not sound abrupt, but also get almost all the way to the full limits of the amplifier. That’s really how we’re able to pull this off.