JBL Px300.4 vs GTO75.4 II

[TxIceMan 10+ year member]

I'm looking really hard at getting one of these 2 amps to power Rainbow SLC265's up front and some rear coaxials. Any glaring differences? Which one should I get?

TxIceMan

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[bballrrt06 10+ year member]

hands down the 300.4 unless cost matters //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[billabongcr 5,000+ posts]

pretty sure both are for sale on the forum right now

 

[TxIceMan 10+ year member]

hands down the 300.4 unless cost matters //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Cost is not an issue, in this case. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[WhoSayWho? 5,000+ posts]

I have the 300.4 and i have been very happy with it.

Will the 75.4 put out the power you need up front? Is it what it sounds like 75 x 4 at 14+ volts.

If price is not an issue then I do not see any reason to even debate it. Go with the 300.4.

 

[squeak9798 5,000+ posts]

It really depends on your needs.

I made this decision recently myself.

I don't use the onboard xovers, so the more advanced xover functions of the PX300.4 didn't benefit me any. And for relatively small difference in power, I couldn't justifying paying the extra $150.

So I went with the GTO75.4II

If you will use the slightly more advanced xover features, and think the difference in power is worth the price, then go for the PX300.4

 

[squeak9798 5,000+ posts]

Will the 75.4 put out the power you need up front? Is it what it sounds like 75 x 4 at 14+ volts.

No, it's rated 104w x 4 @ 4ohm

 

[TxIceMan 10+ year member]

It really depends on your needs.
I made this decision recently myself.

I don't use the onboard xovers, so the more advanced xover functions of the PX300.4 didn't benefit me any. And for relatively small difference in power, I couldn't justifying paying the extra $150.

So I went with the GTO75.4II

If you will use the slightly more advanced xover features, and think the difference in power is worth the price, then go for the PX300.4

^^ That's the kind of response I've been looking for. What exactly is the purpose of the onboard xovers? All I want to be able to do is provide clean power for my rainbows up front and whatever name-brand coaxials I put in the back (Pioneer, Alpine, Rainbow, Diamond...whatever) Would the crossovers be helpful in this type of application?

 

[dx2995 10+ year member]

will the px300.4 be enough to power the Rainbow CMX kicks?

 

[TxIceMan 10+ year member]

will the px300.4 be enough to power the Rainbow CMX kicks?

no...I'm puttng in Rainbow SLC 265's or are you hijacking my thread? //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[dx2995 10+ year member]

no...I'm puttng in Rainbow SLC 265's or are you hijacking my thread? //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

I was just curious. WTF.

 

[squeak9798 5,000+ posts]

^^ That's the kind of response I've been looking for. What exactly is the purpose of the onboard xovers? All I want to be able to do is provide clean power for my rainbows up front and whatever name-brand coaxials I put in the back (Pioneer, Alpine, Rainbow, Diamond...whatever) Would the crossovers be helpful in this type of application?

The purpose of the crossovers is to limit the frequency range being played by the speakers. In your case, you would specifically want to limit the amount of low frequency content being reproduced by both your front and rear speakers. If you don't have a crossover you will be using to highpass both sets of speakers, such as one that may be built into the headunit, then you will need to use the crossovers built into the amps.

The PX300.4 offers the nice feature of selectable 12db/oct or 24db/oct slopes. This is a feature the GTO75.4II does not offer.

But if your headunit has built in crossovers, this may be a feature you won't be using on the amplifier.

 

[TxIceMan 10+ year member]

The purpose of the crossovers is to limit the frequency range being played by the speakers. In your case, you would specifically want to limit the amount of low frequency content being reproduced by both your front and rear speakers. If you don't have a crossover you will be using to highpass both sets of speakers, such as one that may be built into the headunit, then you will need to use the crossovers built into the amps.
The PX300.4 offers the nice feature of selectable 12db/oct or 24db/oct slopes. This is a feature the GTO75.4II does not offer.

But if your headunit has built in crossovers, this may be a feature you won't be using on the amplifier.

Very interesting...My head unit will be the Kenwood DDX8019 which should be out later this week.

 

[squeak9798 5,000+ posts]

Well, I did some quick searching but wasn't able to find any detailed specs of that Kenwood. So I'm not sure if it already has adequate crossover features or not.

 

[TxIceMan 10+ year member]

Well, I did some quick searching but wasn't able to find any detailed specs of that Kenwood. So I'm not sure if it already has adequate crossover features or not.

Yeah..I know...hopefully Kenwood will put the manual or more detailed specs online this week when its released.