Same RMS at different ohms...

[Mugen 10+ year member]

You guys made good points I guess, but I still don't see how it's not limiting the amp. If it can do 1000w at 4ohms, it should easily be able to do MUCH more at 1ohm, right (at least, all other amps lead me to believe that)? So, why make it only do 1000w @ 1ohm? How can it pushing more power hurt? It can't. You guys argued that it does the same no matter what impedance, which is good and all, but why not get maximum performance? What if you're running 1000w @ 4ohms then get another speaker to get a final 2ohm load. Most other amps would give you more power, but on one of these, you'd be stuck with the same power cut in half because it does the same instead of more at lower impedances.

I don't see how you guys don't get what I'm saying. What you would rather purchase:

Amp 1:

1000w @ 4ohm

2000w @ 2ohm

3000w @ 1ohm

or

Amp 2:

1000w @ 4ohm

1000w @ 2ohm

1000w @ 1ohm

See what I'm saying? A typical amp would give you more power with a lower impedance, but Amp 2 gives you the same "weakest-link" power no matter what. How does Amp 2 consider it a feature to cut off so much power? They both do the same exact amount at 4ohm, but the first amp does much more at 1ohm, what would you rather purchase...?

 

[JimJ 5,000+ posts]

If it can do 1000w at 4ohms, it should easily be able to do MUCH more at 1ohm, right (at least, all other amps lead me to believe that)?

Maybe, maybe not. Maybe the manufacturer didn't want to have a mountain of returns from users that didn't know what they were doing and ran the amp into very low impedance loads...maybe the design of the amp itself limits how low it will go.

For someone that doesn't need all that extra power, having an amp that provides a relatively constant output over a wide range of impedances might be a handy thing.

 

[XTRProBoy 10+ year member]

Why is it bad? It is not limiting but more accomodating

It's arguable. I mean what it comes down to is it's a different mentality of amp design/manufacturing. It's basically one extreme where the other extreme is a "high current" amplifier which varies it's output inversely proportional to the number of ohms and directly proportional to the power input voltage. This is how I think of it anyway. And personally I'd rather the unregulated high current amp myself.

Note that JL does offer amps without the "Regulated Intelligent Power Supply" at lower prices (something they didn't do back when they started offering amps as I recall).

To me RIPS is an interesting feature and nothing more. It's relatively pricey and not really necessary unless you plan on changing the load you're driving like you change your underwear, lol. I mean you pick your sub(s) and pick your amp so you run the lowest impedance you can for the most power and there you go. (Or you pick the amp and then the sub(s) but you get the idea, all the same thing.)

RIPS and other such systems offer something interesting in the fact that you never have to worry about using the lowest impedance the amp is stable into, to get the most power. Power stays relatively the same regardless of the load impedance. But you pay quite a bit for that "luxury" and if you're gonna buy sub(s) and stick with them, you could be otherwise saving a lot of money. Furthermore even upon replacing sub(s) you could always easily buy for the same total impedance later on.

They are nice amps, yes, but just not something I see as necessary or useful personally.

In other words some people can see it as a bad thing some people can see it as a great thing. It's just a different way of making an amp.

 

[squeak9798 5,000+ posts]

For someone that doesn't need all that extra power, having an amp that provides a relatively constant output over a wide range of impedances might be a handy thing.

//content.invisioncic.com/y282845/emoticons/word.gif.64b12e39f936af3b4fff38a1c0bd0244.gif

It is a benefit to some. It may not be to you...but that doesn't mean it is not to everybody. Like I said before...it's preference.

As far as this cost thing a couple people keep mentioning.... //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif As Jim mentioned earlier....there are much more expensive amps that output much less power. JL is competitively priced for it's place in the market.

 

[joetama 5,000+ posts]

Maybe, maybe not. Maybe the manufacturer didn't want to have a mountain of returns from users that didn't know what they were doing and ran the amp into very low impedance loads...maybe the design of the amp itself limits how low it will go.
For someone that doesn't need all that extra power, having an amp that provides a relatively constant output over a wide range of impedances might be a handy thing.

Indeed.... Too many people equate more wattage with something being better.... Not always true...

 

[helotaxi 5,000+ posts]

I don't see how you guys don't get what I'm saying. What you would rather purchase:
Amp 1:

1000w @ 4ohm

2000w @ 2ohm

3000w @ 1ohm

or

Amp 2:

1000w @ 4ohm

1000w @ 2ohm

1000w @ 1ohm

See what I'm saying? A typical amp would give you more power with a lower impedance, but Amp 2 gives you the same "weakest-link" power no matter what. How does Amp 2 consider it a feature to cut off so much power? They both do the same exact amount at 4ohm, but the first amp does much more at 1ohm, what would you rather purchase...?

Well if you want to ask a question, ask why the "better" amp above doens't make 4000W @ 1 ohm? It's limiting something as well.

I don't think that you are understanding what the others in this post are saying. If it isn't an important feature to you, don't buy the amp. If you think that an amp must be able to make more power into a lower impedance load, then buy one that does.

This isn't a recent development either. The first Soundstream Reference line had a similar feature. Two power supply rails that were manually switched allowing the amp to make max power @ either 4 ohm bridged or 1 ohm bridged. SS did it for the same reason that JL did. It allowed one series of amps to accomodate thier entire line of speakers and subs and the myriad ways that their customers would use them.

If flexibility isn't such an important feature in the grand scheme of things, why do most subs have a DVC option?

 

[thylantyr 10+ year member]

You guys made good points I guess, but I still don't see how it's not limiting the amp. If it can do 1000w at 4ohms, it should easily be able to do MUCH more at 1ohm, right (at least, all other amps lead me to believe that)? So, why make it only do 1000w @ 1ohm? How can it pushing more power hurt? It can't. You guys argued that it does the same no matter what impedance, which is good and all, but why not get maximum performance? What if you're running 1000w @ 4ohms then get another speaker to get a final 2ohm load. Most other amps would give you more power, but on one of these, you'd be stuck with the same power cut in half because it does the same instead of more at lower impedances.
I don't see how you guys don't get what I'm saying. What you would rather purchase:

Amp 1:

1000w @ 4ohm

2000w @ 2ohm

3000w @ 1ohm

or

Amp 2:

1000w @ 4ohm

1000w @ 2ohm

1000w @ 1ohm

See what I'm saying? A typical amp would give you more power with a lower impedance, but Amp 2 gives you the same "weakest-link" power no matter what. How does Amp 2 consider it a feature to cut off so much power? They both do the same exact amount at 4ohm, but the first amp does much more at 1ohm, what would you rather purchase...?

I've analyzed this just like you along time ago. This type of design

has pros/cons. It comes down to a few issues.

1. Amp #1 looks sweet, why buy amp #2 ? First, there is a power difference,

one amp is 3kw and the other one is 1kw. The 3kw amp has potential to cost

more, the design may be beefier. It comes down to costs and space. I'd choose

amp #1 if possible as long as you can do an install to take advantage of the

impedance issue to get max power.

2. If your reference point starts with 4 ohms and you work your way down,

amp #1 type of design is superior because you get more power into

each parallel load.

3. On the other hand, if both amp #1 and amp #2 was the same power

at 1 ohm, the power regulating design has the upper hand if you add more

stuff and make the impedance higher.

 

[DejaWiz 5,000+ posts]

It comes down to planning your build and selecting the best equipment for what you want to achieve (budget aside).

If a regulated amp is the better choice, hurrah. If a non-regulated amp is the better choice, then hurrah again.

 

[squeak9798 5,000+ posts]

This isn't a recent development either.

//content.invisioncic.com/y282845/emoticons/word.gif.64b12e39f936af3b4fff38a1c0bd0244.gif

Bruce Macmillan was lead designer for the JL Slash series amps. He was with PPI about 20 years ago and designed the 2350DM which has a similar, but a little less complex, design. And that amp was from the early 90's.

 

[CBFryman2 5,000+ posts]

its not limiting anything //content.invisioncic.com/y282845/emoticons/fyi.gif.9f1f679348da7204ce960cfc74bca8e0.gif

except efficency

 

[thch 10+ year member]

except efficency

why would this significantly impact efficiency?

as to all others: Do not refer to these amps as "Regulated". that is a seperate issue. in the RIPS acronym, REGULATED is the part that means "equal power output for 10V-15V input" and INTELLIGENT is the part that means "equal power for various speakers."

when you talk to others, this reference to "regulated" may be mistaken depending on if the person has seen more then just JL amps or not.

 

[CBFryman2 5,000+ posts]

Have you seen the efficency rating of regualated amps like the 1000/1? Most A/B designs are at least 5-10 % more efficent.

On top of that, word has it competition organizations that put amps in classes by how much power they do at 4ohm would put the 1000/1 in the same class as the average 4000w amp. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[T3mpest 10+ year member]

You guys made good points I guess, but I still don't see how it's not limiting the amp. If it can do 1000w at 4ohms, it should easily be able to do MUCH more at 1ohm, right (at least, all other amps lead me to believe that)? So, why make it only do 1000w @ 1ohm? How can it pushing more power hurt? It can't. You guys argued that it does the same no matter what impedance, which is good and all, but why not get maximum performance? What if you're running 1000w @ 4ohms then get another speaker to get a final 2ohm load. Most other amps would give you more power, but on one of these, you'd be stuck with the same power cut in half because it does the same instead of more at lower impedances.
I don't see how you guys don't get what I'm saying. What you would rather purchase:

Amp 1:

1000w @ 4ohm

2000w @ 2ohm

3000w @ 1ohm

or

Amp 2:

1000w @ 4ohm

1000w @ 2ohm

1000w @ 1ohm

See what I'm saying? A typical amp would give you more power with a lower impedance, but Amp 2 gives you the same "weakest-link" power no matter what. How does Amp 2 consider it a feature to cut off so much power? They both do the same exact amount at 4ohm, but the first amp does much more at 1ohm, what would you rather purchase...?

Most amps that put out 4k will cost more than an amp that's regulated across impedences at 1k. Unless we really start to compare apples to oranges.

I'd say

Amp 1:

300@ 4ohm

600w @ 2ohm

1200w @ 1ohm

or

Amp 2:

1000w @ 4ohm

1000w @ 2ohm

1000w @ 1ohm

is a more fair comparison. The top amp will still be priced as a "1000 watter". In this case, at 1 ohm, amp a's a bit better, but overall amp b is much more versatile, you can apply a similar amount of power to any setup.

 

[JimJ 5,000+ posts]

word has it competition organizations that put amps in classes by how much power they do at 4ohm would put the 1000/1 in the same class as the average 4000w amp.

Link to this please...

 

[Flipx99 5,000+ posts]

USACi used to but the rules are different now.

I wish I could be as good of a smartass as JimJ but I am not.