JL audio HD 900/5

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bdubs767
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JL audio HD 900/5

Post by bdubs767 »

just me or does this amp seem like the most practical amp ever put out on the car audio market...

I know I sound like a traitor but for new cars where you can barley fit any amps, this thing is so small it could feet under the passenger seat and supply 100 x 4 @ 1-4 ohms and 500 x 1 @ 1-4 ohms :o ... Sounds like a dream amp.


http://mobile.jlaudio.com/products_amps.php?amp_id=537
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Post by mhyde71 »

yeah i suppose if you like class d gear... too bad it wasnt a/b + d... that would be an enhancement, and almost make it a perfect choice.

but i have to say I really dont know much about the JL gear as far as their amps are concerned - but defo interesting
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Post by stipud »

Full range class D doesn't have a lot of the sound quality issues that the subwoofer-only class D amps have (e.g. missing harmonics). With my home audio gear I tried two setups using Audiosource amps:

1) Bi-amped class A/B with 100W going to each individual speaker
2) A single class T powering the whole shebang with 200W per side

The difference was almost indestinguishable... if anything the class T was better built and had better subjective sound quality than the cheaper A/B amps. I am sure a proper audiophile A/B amp would be better, but at what cost? Far bigger size, far more heat, and far more electric draw.

This JL amp is definitely an amazing feat of engineering. I am very impressed they managed to pack that much power into such a small chassis. If I could afford one I would love to try it out, but unfortunately the high end JL gear has never been in my budget range.
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Post by Eric D »

I also like that JL amp. My only concern is reliability. It has a lot of electronics in a very small space. I am not certain it will hold up over time.
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Post by Phoenixcolt »

I have been reading about this amp since I found out about it in a passing thread last week somewhere!

Even the low price of this amp is 700 bucks. I don't want to blow that kind of money but 100x4 on my RSd comps front/coaxes rear and 500 to an RSDC102 when it get the install going sounds f-ing sweet...

I have a beautiful barely used RSd500.4 and an unused Alpine PDX-5 laying in my closet. Can't wait to get things set up and start playing with different configurations!
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Post by Audiophiliac »

If I had the $$$, I would have that JL. I will have to see what I can get one for. We are a JL Home Audio dealer...surely they will give me some kind of deal. ;)
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Post by Mackenzie »

That amp is tiny.. Btw dubs indy>pats :P
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Post by rscecil007 »

Phoenixcolt wrote:I have been reading about this amp since I found out about it in a passing thread last week somewhere!

Even the low price of this amp is 700 bucks. I don't want to blow that kind of money but 100x4 on my RSd comps front/coaxes rear and 500 to an RSDC102 when it get the install going sounds f-ing sweet...

I have a beautiful barely used RSd500.4 and an unused Alpine PDX-5 laying in my closet. Can't wait to get things set up and start playing with different configurations!
$700? Where'd you'd find one that cheap? :?:
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item

Post by kg1961 »

i have used and own a JL slash 300/4 300/2 and 500/1 i have to say great amp used them for the last 3 years clean good no problems, never shut down
they sound to me as good as my reactor 5/500 when i used both in the same car
now the new one look great but never heard them
most of my gear is gone :liar:
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Post by audiophyle_247 »

100w x 4 @ 4ohm but 75w x4 @ 2 ohm, hows that work?

Also noticed the THD rating for the sub is at 5ohm, but the power ratings are from 1.5~4 ohm.

Size wise it is damn near the same as the PDX-5, which I know for a fact are incredibly underrated. Does JL give spec sheets with the amps?
I had awesome results with my old PDX-5, and at half the price it seems a no brainer to me. The only discernible difference being a 500w sub ch vs 300w sub ch, but even then I have installed several PDX-5s with spec sheets showing 400+ on the sub channel.
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Post by Phoenixcolt »

audiophyle_247 wrote:100w x 4 @ 4ohm but 75w x4 @ 2 ohm, hows that work?

Also noticed the THD rating for the sub is at 5ohm, but the power ratings are from 1.5~4 ohm.

Size wise it is damn near the same as the PDX-5, which I know for a fact are incredibly underrated. Does JL give spec sheets with the amps?
I had awesome results with my old PDX-5, and at half the price it seems a no brainer to me. The only discernible difference being a 500w sub ch vs 300w sub ch, but even then I have installed several PDX-5s with spec sheets showing 400+ on the sub channel.
The PDX-5 I have says the sub channel is 414...which is pretty damn underrated, I was surprised and enlightened.

I wonder if JL has birth sheets in theirs and if they are also underrated. If that thing could do 600 or so to the sub, it'd be awesome.
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Post by Phoenixcolt »

rscecil007 wrote:
Phoenixcolt wrote:I have been reading about this amp since I found out about it in a passing thread last week somewhere!

Even the low price of this amp is 700 bucks. I don't want to blow that kind of money but 100x4 on my RSd comps front/coaxes rear and 500 to an RSDC102 when it get the install going sounds f-ing sweet...

I have a beautiful barely used RSd500.4 and an unused Alpine PDX-5 laying in my closet. Can't wait to get things set up and start playing with different configurations!
$700? Where'd you'd find one that cheap? :?:
Sonicelectronix and Amazon.
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Post by rscecil007 »

One of the JL guys posts over on DIYMA forums (user id msmith I think), and posts some good info, how they calculate THD, etc etc. Some pretty interesting stuff. I think it's this thread here b/c I have it bookmarked:

http://www.diymobileaudio.com/forum/pro ... -amps.html

Yeah it's 11 pages or whatever, but there's good info buried in there if you feel like reading...
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Post by dedlyjedly »

That's Manville, he's the VP of marketing for JL or something like that. I have a lot of respect for JL due in large to that guy. He knows his stuff and represents his company and the 12 volt industry in general very admirably. How many marketing guys can you say that about!?
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bdubs767
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Post by bdubs767 »

Mackenzie wrote:dubs indy>pats :P
eat shit lol
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