About the JL Audio HD Series HD900/5
Small amps, big power
Small amps, big power
JL Audio's HD Series amplifiers offer high performance from an ultra-compact chassis. These Class D amplifiers use less power, take up less space, and generate less heat than traditional amp designs — you can even stack them up to create a sweet-looking installation.
JL Audio technology goes to work for you
HD Series amplifiers reproduce your music with exceptional accuracy, so you'll hear high-fidelity sound even under the most demanding conditions. JL Audio uses Single Cycle Control™ technology to eliminate the excessive signal distortion that's plagued Class D amplifiers in the past. Differential-balanced inputs eliminate noise before it hits the preamp stage, and allow you to connect the amp to just about any in-dash stereo. You'll hear clear, true, studio-quality audio, exactly what you expect from JL Audio.
Power your entire system with one compact amp
The 5-channel HD900/5 amplifier pushes 100 watts RMS per channel to your front and rear full-range speakers, plus 500 watts RMS to a sub — all from a 2" tall chassis that's about the size of a sheet of computer paper. Or, you can bridge the front and rear channels to drive 150 watts RMS into two speakers, while still running your sub at 500 watts.
The regulated power supply allows this amp to deliver its rated power to a wide range of impedances, even when voltage levels drop during heavy use. Removable power and speaker plugs make it easy to pop this amp out if you need the space in your cargo area.
Some extra touches
You can use JL Audio's optional stack kit to mount one HD Series amp on top of another, so you can maximum power from minimum space. JL's wired remote allows you to control your HD amp's volume from your front seat.
- 5-channel amplifer
- 100 watts RMS x 4 at 4 ohms + 500 watts RMS x 1 (at 1.5-4 ohms)
- 75 watts RMS x 4 (at 1.5-3 ohms) + 500 watts RMS x 1 (at 1.5-4 ohms)
- 150 watts RMS x 2 bridged (at 3-6 ohms) + 500 watts RMS x 1 at (1.5-4 ohms)
- variable high-pass filter on front and rear channels (50-500 Hz, 12 or 24dB/octave)
- variable low-pass filter on subwoofer channel (50-500 Hz, 12 or 24dB/octave)
- subsonic filter on sub channel (24 dB/oct at 30 Hz)
- removable power and speaker plugs
- optional wired remote for level control
- optional HD stacking kit for stacking multiple HD amps together
- Class D amplifier design
- MOSFET power and output stages
- differential-balanced inputs eliminate noise from your vehicle's electrical system
- speaker- and preamp-level inputs (speaker-level input requires an optional adapter)
- preamp outputs
- 4-gauge power and ground leads and a 60-amp fuse recommended wiring and hardware not included with amplifier
- no onboard fuses when installing multiple amps in a system, an additional 60-amp in-line fuse between the distribution block and the amplifier is recommended
- 10-3/4"W x 1-15/16"H x 8-5/16"D
- warranty: 2 years
- Our 60-day money-back guarantee
- MFR # 98223
What's in the box:
- 5-Channel class-D full-range amplifier
- Power/Ground/Turn-On plug
- 3 Speaker connection plugs
- 3mm Allen-wrench
- 5mm Allen-wrench
- Mounting bolts
- Owner's Manual
JL Audio HD Series HD900/5 reviews
Great sound quality and power! I can definitely hear improvement in power and sound quality, changing from my previous Audison Amps (Audison AP4 D & AP 1D). Noise seem to be lowered a little as well. Powering all my speakers adequately. Very happy with the results for now in search of never ending upgrades. Setup in 2016 Tesla Model S: -High Level from giant iPad -Audison Bit TEN -Hertz Mille MLK 1650.3 -JL 10W6v3-D4
Pros: Great Sounding Amp, Small
Cons: Cannot tell if this amp beats others like Rockford or Mcintosh. I surely will try others.
0 of 0 found this helpful
Awesome Amp with much power. Good quality sound all around and compact. Give much bass and very powerful. Quality of AMP seems really well built.
Pros: Good sound and Powerful
2 of 2 found this helpful
This amp has brought the detail and sound quality that was missing from my system I will be upgrading my speakers in the weeks to come but it has increase the sound quality of the speakers I already have. I have some JL C2 5.25 and Rockford power 6x9 and a JL W7 10 sub
Pros: Small, sound quality
1 of 1 found this helpful
Has worked since March of 2013. Over 5 years now. No problems. Focal component speakers (4), JL Audio 10" sealed sub (3v3), Kenwood head unit.
3 of 3 found this helpful
I wont waste time repeating all the great comments already being said, which in my opinion is true. I want to mention the Marine version of this amp. I think the bigest benifit of this amp is its regulated power supply. It may not be as important in a vehicle which is usually running and rarely off, but to boat owners who spend most of the time on a beach or tied up on a lake listening to music with the engine off; the amps ability to put out it's rated power when battery power drops from the 14volts when engine running and the low drawn 11volts after listing to music for several hours is awesome!! Unlike all other amps that drop output watts as the voltage drops, this amp won't drop output or start cutting off. Just look at all other amps, including non HD JL amps and they have their highest output rating at 14 volts, which is only available with the engine on. They will then have a lower rating at 12 volts, which is a fully charged battery . Once you start listening to music for a little while this quickly drops to around 11 volts which is real world voltage on a boat with engines off, This amp will still provide it's rated power output Awesome!!!
Pros: Everything especially the regulated power supply.
4 of 4 found this helpful
Feeds 4 Polk MM572 (5x7) speakers and a JL Stealthbox in my '13 Mustang Boss 302 using the stock base stereo. The tone is crystal clear and the bass is strong/solid. If I had a complaint it would be that for my situation the main channels would probably be better served with 50x4 watts vs. the 100 this amp provides. I set the gains per the instructions and the sub was drowned out by the mains. I adjusted the mains as low as possible while still maintaining balance and that brought the sub nicely into the mix. I'd prefer a bit more bass. Just a tiny bit. I don't blame this on the amp......who doesn't want more power?!?! I have plenty of volume and it is rock solid crystal clear from minimum to maximum. I am sure that most fault lies with my stock headunit and feeding the amp with speaker level inputs. With those handicaps the fact that I still have fantastic, clean tone and impressive volume is pretty darn impressive. The amp is compact. controls are straight forward, power to spare, and it runs pretty cool in my application. The plugs for speaker/power hookups are a nice touch.
2 of 3 found this helpful
Great amp. Pushes my Alpine type r 6x8s and Stealthbox from JL perfectly
0 of 0 found this helpful
I just upgraded to this amp a couple of days. So far, I am very impressed. It is expensive, that is without a doubt. But, it's powerful, compact, well-built, and the sound is great. And JL amps are generally pretty bullet proof. It should last a long time. I currently have it powering a set of JBL GTO 609c components. It's bridged pumping out 150w rms to them. The sub channel is running a JL Audio Stealthbox for my Silverado. I will be upgrading a few other things soon, but this amp isn't going to be one of them.
Pros: Compact, powerful, clean sound
Cons: Nothing. You get what you pay for
4 of 4 found this helpful
Compact, powerful. A perfect fit for my Ram.
1 of 1 found this helpful
Finally got this installed! Sounds great. Nicely pushes my two 10's and components in the front and rear doors. Glad to have one amp to do it all.
Pros: Small and one amp to handle all speakers
0 of 0 found this helpful
Perfect whole car amp with the size it can almost fit anywhere you want and it sounds amazing
1 of 1 found this helpful
Excellent amp installed a couple weekends ago and am impressed with it to date. Did not receive the sale price which started a few days after purchase but would still recommend.
1 of 1 found this helpful
This is one impressive amp. I have it powering four 5.25" focal components in the doors and two 10" jl subs under the rear seats. Clarity is amazing.
7 of 7 found this helpful
So I have had the Rockford Fosgate P1000X5 and Apline PDX V9. All of which are very good amps and birth sheets are always higher than expected. Well this little tiny amp makes both of these look bad. I can't explain the differences in any other way than its twice as good as either one and the bass is amazing. The footprint vs the RF is around 6in smaller the Alpine is a little bigger but again it's huge difference in sound clarity and power you will need to turn this unit down. I get the two can be purchased for almost the same cost but there is no equal in 5 channel amps this is king
Pros: size, power never overheats I live in my truck 4 hrs on 3/4 volume still no overheating and low profile
Cons: I guess some say the price but you install this and you will forget all about the price
10 of 10 found this helpful
I bought this amp as a replacement for a 4 year old Alpine PDX-V9, and I can say, it's a well above significant improvement in just SQ and build alone. I really think JL underrates the output power because the gains need to be set somewhat low (as they should be) for proper matchup with a high end 4V head unit. I also read an article in a magazine a few years ago that "some of the Precision Power guys from the early 90's" were involved with the HD amp series design and on JL's engineering team. Regardless, I'm so very happy that I made this purchase & to visit Crutchfield's website to see that it was on sale, made it even better! Best 5-channel amp, PERIOD. I wanted an all JL Audio setup in my car (with the exception of the HU) and it drives all of the speakers flawlessly with little effort. I will say, it can run a little warm to hot, so give it plenty of ventilation and some nice power cables. The power plug seemed sized kind of small (compared to the Alpine) and it was difficult to make the required 4AWG wire fit. Other than that, no complaints! JL Audio HD amps are some of the best you can buy.....your ears & speakers will thank you! System setup is: Pioneer AVIC 8200NEX, JL Audio HD900/5, JL Audio ZR650-CSi, JL Audio C2-650x, JL Audio ProWedge 12" W7, Monster Cable Performance Car power cables/fuses & 12 & 16AWG speaker wire, Monster Cable 404 XLN/402 XLN Xtreme RCA/SUB interconnects. Thanks again Dolly & Crutchfield!!
Pros: Possibly everything? Regulated power supply, S/N ratio, build quality, output power, superior SQ for a class D amplifier, nice built-in crossovers for fine tuning your speakers.
Cons: Can run somewhat warm to hot-needs good ventilation, power connector seems difficult to accept 4AWG wire (although could've been the wire I was using). Seems a little harder on the electrical system (I get the psychedelic effect at night with my headlights with those deep bass notes), might need a deep-cycle battery or higher output alternator to fix that.
17 of 19 found this helpful
I purchased this amp from local jl dealer, runs hot often. Returned to dealer for repair, it has been 1 month & still waiting. Sounds good when operating at normal temperature. Hope you don't have the same problem.
Pros: 108 s/n
Cons: Turn around "repair" time if necessary.
4 of 8 found this helpful
The Bose Centerpoint system in my 2009 Saab is difficult to upgrade because the head unit and Bose amp share controls and crossover functions. The HD900, with its five channels, differential balanced inputs (you must have this to work with the Bose system), high level speaker inputs and size perfectly integrates into the Bose system so that your multiple aftermarket speakers get all the power they need to sound their best.
Pros: The size, power and build quality. Makes me happy every time I turn it up!
Cons: Price, but you get what you pay for!
9 of 9 found this helpful
This is a great purchase. It was a close call between this and An Alpline PDX 5. Both are great amps. Great products from an authorized dealer is my main concern. Warranty covered.
Pros: Clean powerful sound in one package
Cons: Price point on high end
5 of 5 found this helpful
I finally decided to upgrade my sound system in my show car/weekend cruiser so my search began at Crutchfield as their customer service & tech support is top notch. I have limited space to inconspicuously mount an amp in a convenient location in my vehicle so I wanted a nice 5-channel amp. The HD900/5 immediately stood out from the competition. Yes, initially I thought this amp seemed a little expensive, but once I heard the sound quality from its small foot print, all reservations were set aside. I upgraded to a Kenwood DNX692 with the HD900/5 powering a set of JL C5-650's, a set of C5-650x's & I kept my 10" Kicker Solo-Baric Classic in JL's stealth box & I am truly blown away. The sound fullness & clarity is beyond anything that I have personally heard. The performance is phenomenal with great adjustment capabilities & I added the JL HD-RLC remote for front seat control when I want to quickly dial the amp down. The HD900/5 also looks great & with the power & speaker plugs, installation is clean & fast. Every review that I've read, the only consistent complaint seemed to be price. Yes, this amp is not cheap but it easily does the work of multiple amps. When considering how small & powerful it is with the "superior sound quality", in my opinion, there's no comparison. I took advantage of the 10% off sale through Crutchfield & after hearing what this amp can do, I may argue I under paid. The HD900/5 is down right amplification at it's finest.
Pros: Great power, incredible sound quality, compact size, very clean & easy install.
Cons: Not putting this in my daily driver as I may have to buy another one.
13 of 13 found this helpful
First of all, let's get the price question out of the way. The price of this amplifier is stupid expensive, period. That being said, and out of way for any further discussion, this amplifier lives up to every claim made by JL Audio and other Reviewers. I have a small hatchback vehicle with Focal component speaker systems in the 4 doors, and 2 Audiomobile subs in their own box. My previous amp was a JL Audio six channel 600 watt amp. I thought they sounded great, until I replaced that amp with the HD900/5. I expected the subs to sound better overall with the increased power, but the improvement in sub performance was much more than simply volume. The lows were significantly lower, and the overall sound was much cleaner, at comparable volumes. The unexpected improvement in sound quality was in the door speakers. The mid/lows down to 80Hz were significantly stronger, at comparable volumes. The overall sound was fuller at all volume levels. My previous class AB amp was large, heavy, and it ran hot. While it never went into overheat mode, the amplifier would sometimes got too hot to touch for more than a few seconds. The HD900/5 has yet to get more than marginally warm. Also, the HD900/5 is about one third the size and weight of my previous amplifier. Last, but not least, the HD900/5 has a tremendous amount of configuration flexibility, and all of the critical controls are protected under a cover, secured with a screw. This amp is truly a pleasure to own.
Pros: Superior sound quality, powerful, configurable, cooler operation, smaller, lighter.
Cons: Agreed to no further discussion.
19 of 19 found this helpful
This amps powers two sets of JL C5-650's, front and rear and two 10TW1 subs in a sealed box. It produces prodigious amounts of power (my perception). The nicest thing I can think of to say about this amp is that it does what it's supposed to do without notice. It has some nice controls on it, although I use the crossover feature on my head unit and not the amp. One note, setting the input sensitivity per instructions appeared to create a LOT of sub, compared to the mains. Many would say this is a good thing! I ended up turning the sensitivity down to match what sounded best to my ears. I've driven this amp pretty hard for extended periods of time without any noticeable fatigue except to my ears. This is an upscale amp, with upscale performance. I believe it is one of the best values on the market. One last thing- it deserves a quality installation. Feed it plenty of power with at least a 4AWG cable and a good ground!
Pros: plenty of power, compact size, great feature set
Cons: very minor quibbles- does seem to run warm, took a while to tune it correctly.
4 of 4 found this helpful
I replaced a JL 500/5 and a 250/1 powering 4 satellites and 2 subs with this amp. I also moved down to one sub. I am very happy with the sound. the extra 150W to the rear speakers makes quite a difference. The amp seems a lot cleaner than the 500/5, but that could be the extra power to the rears. I set the front and sub crossovers to 80Hz, the rear crossovers to 120Hz, and adjusted the levels per the manual. I have not touched them since and have no plans to. I am very happy with the sound. The modular plug-ins makes install much easier. Like the adjustments being on the opposite side, makes for easier access in my install.
Pros: Clean sound. Very small chassis for a 900W amp. Great power for a whole system amp. Easy adjustments. Clean and easy install.
Cons: Cons....cons.... um... Oh! The subsonic filter! Yes, i had to think to come up with something. Why place it at 30hz?!?! (Yes, i know it's for ported boxes.) I would have like it adjustable, or selectable at 20Hz-30Hz. I have a ported enclosure, the HO110RG-W3v3, and it seems to not be as full with the filter on. I think 20Hz would have been perfect. This is a very minor gripe and really not an issue, still a 5 stars amp!
17 of 18 found this helpful
This amp was a great purchase for what I was looking for. I have a 4 door wrangler and was upgrading the sound system when I ran into the problem of what kind of amp to get. I wanted to power my 4 speakers from the amp but also wanted a sub that had some power. This amp was able to power my C5 650s in the front and C3 650s in the sound bar with the TW5V2 in the stealth box. Perfect size to fit under the seat and more than enough power to keep me happy.
Pros: Powerful Compact 5 channel great for sub and speakers
12 of 14 found this helpful
Had too turn the gains down. Too loud for me. I was looking for a good small amp that fit under the seat. I have a very small car and battery but the amp doesn't seem to mind. Very few adjustments had to be made to get the type of sound quality I was looking for. Even the Eq. on the head unit is almost flat. Great job JL. And Thank You Crutchfield employees for putting up with all my questions. B.T.W. purchase the bass knob, it's a must!
Pros: Lots off power, small, easy set up.
Cons: A little pricey.
10 of 11 found this helpful
I dont really know all the "tech mumbo jumbo". But here is my System, Im running the factory head unit (the 6" touch screen head unit) and this is running into a lower level 6 CH. line output(audiocontrol LC6I) into the JL HD900/5 This amp is powering two sets of Facal P165V15 components which are darn good speakers at $500 a pair. And also powering my 2 JLW3s subs. The shop that installed this said that they were impressed with the actual power this amp puts out when tuned correctly. Ive ran many different type of amp in the past. mostly a four CH. and a Mono amp for all of my systems, and my previous subs and speakers were a lot less then what i have now. I dont think I will ever run anything but a five ch JL . The awesome sound and power you get combined with the unreal small size of this amp makes it and easy choice.
Pros: Small size and power
Cons: when i find one I'll let you know
8 of 10 found this helpful
Very small footprint. Lots of power for its size. The HD900/5 is pushing front/rear Focal 130KR's with 10" sub. This is a perfect amp to power an entire system. Sound is clean. One thing I would like to point out (to my surprise) is the fact that there are a lot of YouTube videos pairing HD Series amplifiers with Focal components; event with the high dollar Utopia Be No.5. That is a bold statement regarding this amplifier. I recommend you use the proper metering equipment to set the gains/crossovers properly to be rewarded with clean, reliable and loud music. Applying sound deadening is like adding icing to the cake. In my garage,I tested the HD 900/5 by playing hip-hop for almost 100 minutes (power supply used) at 90% volume (only 90% because I was nervous about my component speakers). WOW! This amp did not shut down OR go into "protect" mode. Amplifier housing was warm/hot but that is to be expected after over 1.5 hours of playing. This amp is under rated and will certainly complement any 6x9, 6.5, 5.25 or component speaker set. Now I'm confident to open up my truck doors and play some music at BBQ's and family gatherings. There are higher priced amplifiers for the same or less amount of power but anything beyond the HD900/5 and you will start to pay more and get less...the point of diminishing returns.
Pros: >Very flexible >Highly adjustable: high/low level inputs, high/low pass filters >Small footprint >Does not get as hot compared to traditional AB amplifiers
Cons: >Would like to see the JL Audio logo lit. >Performance will tempt you to buy another
21 of 21 found this helpful
This small amp has the ability to power 4- JL Audio C2-690, 2- C2-075 tweeters and a W3V3 12 inch sub. Amazing sound in a small package. This single amp does the work of two amps in an exceptional manner. My car is a concert hall thanks to this amp and the components it powers.
Pros: Great sound, small package, One amp to power the entire system, stealth.
9 of 9 found this helpful
This is a great amp for the money. Chose this over the smaller XD line and I have no regrets. Power goes to bi-amping a Focal 3 way set in the front and two tens in the back. It sounds like nothing, which is what amps should sound like, completely transparent. Top audio competitors are using this line of amps and that says a lot. I bought the open box version and saved a hundred bucks. It came exactly the same as if it were new, not one bit of difference. Highly recommended!
Pros: Awesome sound and power.
Cons: You get what you pay for....
13 of 15 found this helpful
This is a great amplifier and my third JL Audio amp. I have the amp powering 4 JL Audio XR650 speakers C5 tweeters and a 10w7v2 subwoofer. I could not be happier with the power that this amp can pump out. It runs fairly cool and I have yet to be able to force it into a protect mode with long listening sessions at high volumes. Another plus is this amp is SMALL. I have it tucked away under the back seat in the factory location. If you buy this amp it, you will not be disappointed! Yes it is expensive but it is worth every penny.
15 of 16 found this helpful
This amp gives you true rated power across a wide range of supply voltages, and in a compact chassis. The sound quality is superb, but again it always makes the rated power and stays cool. Paper specs do not do justice, this amp is worth every penny, it is that good.
14 of 14 found this helpful
I have this amp pushing a 8w7. Everyone thinks i have 2 12's. it's also powering my to alpine component sets. It all sounds great..one of the cool things this amp does is it don't leave you with out music when it over heats it just turns the power down. so long as you turn your stereo down it will continue to sound great. I can't say enough about this amp it's simply awesome.
14 of 14 found this helpful
This amp is seriously sick! i got a JL audio stealth box for my 07 mustang which has a 13w6 in it. I was using an amp that was supposedly pushing 850w rms to it but this thing is definitely louder and cleaner. I haven't hooked it up to my speakers yet, but i already know its gonna sound amazing. If you want a one amp solution to power your whole system, do yourself a favor and check this one out.
9 of 31 found this helpful
After looking at Alpine and JL Audio digital amps for a while, JL finally came out with a perfect 5 channel that fit my needs. I swapped out two amps for one. And this one JL has great power. The sound is extremely clean, though the bass is not as loud as my old MTX mono amp that was rated the same at 1x500. But I didn't mind since I was trying to clean the bass to a more tight sound. I got new Focal polyglass 6.5 components, and pure heaven. Sound is amazaing. Focal and JL are top notch. Subs are 2 Infinity 12 inch Perfects combined to 2 ohms. I am still thinking about scaling down size to one 10 inch JL W6 and slamming that small sub hard. Amp gets hotter than expected. The size is unbelievably small. Get a great complete set-up in one small amp! Solid
17 of 19 found this helpful
I recently swapped my JL 300/2 and 500/1 for a HD600/4 and this HD900/5 and the difference is incredible. Sound quality is amazing and the space requirements are very minimal. The 10w3 woofer in a sealed box I have running off of the sub channel seems more precise and less "boomy" and I use the other channels bridged to a set of JL C5 components for the back doors. The sound quality on the back speakers is superb as well. This amp does seem to run a little bit warmer than the amps I had before, but I've had zero problems with either amp even after many continuous hours of loud volume levels. Overall, this amp and its 600/4 counterpart are worth every penny.
23 of 26 found this helpful
More details on the JL Audio HD Series HD900/5
Features & specs
|RMS Power Output (Watts x Channels)||
100 x 4 |
500 x 1
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||75 x 4|
|Bridged Power (Watts x Channels)||150 x 2|
|Minimum Impedance Bridged||3|
|Minimum Impedance Unbridged||1.5|
|Best Frequency Response||12-28K Hz|
|THD at Rated RMS Power||0.03%|
|Signal to Noise Ratio||108 dB|
|Low-Pass Crossover Frequency||50-500Hz (ch 5)|
|Low-Pass Slope (dB/octave)||12 or 24 dB/oct|
|High-Pass Crossover Frequency||50-500Hz (ch 1-4)|
|High-Pass Slope (dB/octave)||12 or 24 dB/oct|
|Bass Boost Frequency||N/A|
|Speaker Level Inputs||RCA|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Five-Channel Full-Range Amplifier: The JL Audio HD900/5 is a Class D five-channel, full-range amplifier that is rated at 75 to 100 Watts RMS x 4-channel (front/rear) and 500 Watts x 1-channel (subwoofer) in 1.5-4-ohm at 20 to 20kHz with a signal-to-noise-ratio of 108 dB and a total harmonic distortion of 0.03% while receiving 11 to14.5 Volts. The front and rear channels of the amplifier can also be bridged to output 150-200 Watts RMS x 2-channel in 3 to 8-ohms.
High-Fidelity Class D (HD) With Single-Cycle Control: The JL Audio HD900/5 utilizes patented Single Cycle Control Class D technology for all channels. This technology delivers reference-grade sonic performance while requiring far less current from the vehicle's electrical systems than a conventional amplifier. Single Cycle Control is a unique approach to controlling a full-range Class D amplifier. By tracking the audio signal, comparing it to the real PWM waveform and then correcting it in each and every cycle (over 400,000 times per second), a multitude of distortion-causing mechanisms can be tightly controlled to enable pristine amplification. While there are certainly less expensive ways to make a full-range switching amplifier, no other Class D control system works faster or more accurately than Single Cycle Control.
Compact/Efficient Design: The JL Audio Class D amplifier on average is 13% smaller overall and over 1/2-inch shorter in height than most class AB amplifiers. The HD900/5 features outstanding overall efficiency (80% at 1/2 rated power) which allows for huge power from a tiny chassis and is easy on your vehicle's charging system, drawing 60% less current than a class AB design of equal power.
R.I.P.S. (Regulated, Intelligent Power Supply): R.I.P.S. stands for "Regulated, Intelligent Power Supply" and is a central feature of the JL Audio's JL Audio HD amplifier. The JL Audio R.I.P.S. System ensures consistent power delivery over a wide range of battery voltages and load impedances. This technology provides optimum power at any impedance level between 1.5 ohm to 4 ohm per channel and at any vehicle voltage level between 11V and 14.5V.
- Regulated Power Supply: "Regulated" means that the power supply adjusts its operation so as to maintain the amplifier's rated power output and low distortion operation over a wide range of vehicle voltages (11V-14.5 V). This allows the JL Audio JL Audio HD amplifier's the rail voltage and clean power output to remain stable in real-world car-audio systems, resulting in superior fidelity and stability.
- Intelligent Power Supply: The "Intelligent" portion of the R.I.P.S. System is a circuit that actually monitors output current to optimize the amplifier's output power over a wide range of load impedances (1.5 ohm to 4 ohm per channel). The R.I.P.S. System detects the actual impedance being driven and adjusts output rail voltages to deliver optimum output. The entire process is seamless, automatic, and results in incredible dynamics for satellite channels and consistent power output for a wide range of subwoofer configurations. It also takes into account the real impedance of your car-audio system, rather than relying on often inaccurate assumptions based on a speaker's rated impedance.
RealSink Heat Management With Rollback Protection: This JL Audio amplifier employ and advanced type of heat management, called RealSink. This features takes advantage of convection and radiation effects to remove heat from the amplifier circuitry. For optimum cool performance, the vertical heat sinks located at the sides of the amplifier should be exposed to as large a volume of air as possible. If a JL Audio HD amplifier should ever reach an unsafe temperature, its unique Advanced Rollback Protection circuit also adjusts power until the amplifier cools down, without ever shutting your music down.
Differential-Balanced Inputs: The JL Audio amplifier features differential-balanced input architecture to effectively control noise and ensure compatibility with a wide variety of source units, including many OEM systems. Without resorting to line output converters, you can directly connect most OEM source units to the JL Audio amplifier without creating any noise or compatibility issues. Unlike conventional single-ended inputs, the differential-balanced design does not connect one side of the audio signal to chassis ground. This eliminates any voltage sensitivity between one input terminal and ground and greatly reduces the incidence of alternator whine in a typical car audio installation. The JL Audio HD amplifier provides range switching on each of its inputs via the "Input Voltage" switch. This permits connection to a wide range of source voltages while retaining excellent sensitivity setting precision.
Note: You will need three speaker wire to RCA adaptors (136XDCLR2S, sold separately) to connect this amplifier to your headunit via speaker-level.
Protection Circuitry With Status Indicator Lights: There is a single multi-color LED on the control panel of the amplifier to indicate the amplifier's operating status.
- Flashing Green: When the LED is flashing green, the amplifier is powering up and audio output is muted.
- Constant Green: This LED lights green to indicate that the amplifier is turned on and operating normally.
- Constant Red: This Red LED lights to indicate that the amplifier has exceeded its safe operating temperature, putting the amplifier into a shelf-protection mode, which reduces the power output of the amplifier. The red light will shut off and the amplifier will return to normal, full-power operating mode if the heat sink temperature drops back to a safe level.
- Constant Yellow: This amber LED lights to indicate that the impedance of the speaker load connected to the amplifier is lower than the optimum impedance load range for the amplifier. When this light is on, a protection circuit engages and reduces the power output of the amplifier. The amber indicator will also light when a short-circuit is detected in the speaker wiring.
- Alternating Red/Green: The LED alternated between Red and Green to indicate that the amplifier is experiencing a fault that may require service of the amplifier, its wiring, or the vehicle's operating system. Audio is muted when this fault occurs.
Note: There is only one condition that will shut down the HD900/5 completely and that is if the battery voltage of your vehicle drops below 10 volts.
Mounting Options: The HD900/5 has two mounting option to choose from during installation.
- Standard Mounting: The standard method of mounting requires removal of the four corner caps with the included hex-wrench. Using the appropriate mounting screws (not included), you can then secure the amplifier in all four corners and replace the corner caps.
- Lateral Mounting Feet: Lateral Mounting Feet are also included with the HD900/5 to provide an alternative mounting option. Each mounting foot should be attached to the bottom of the amplifier by screwing the provided bolts into the bottom of the amplifier and up into the corner cap with the supplied hex-wrench. Then, using the appropriate mounting screws (not included), you can secure the amplifier by its four lateral mounting feet.
Control Panel Cover: The HD900/5 features a Control Panel Security Cover which protects and hides the amplifier's controls. When installed, the cover ensures that the amplifier's settings are not accidentally changed while creating a clean aesthetic look for the amplifier and your installation. The control panel security cover is pre-installed at the factory and must be temporarily removed for access the amplifier's controls. The security cover is secured by a single hex-head screw.
Simplified Gain Setting: The amplifier's R.I.P.S. feature also allows for easy gain setup. Because the amplifier will always deliver the same amount of power within its operational range of impedances and supply voltages, the maximum, unclipped output is very predictable. This makes setting the gain level of the amplifier via the input sensitivity control very simple. All you need is Digital AC Voltmeter (142TK12V, sold separately) and a Test CD Disc (503CD104, sold separately) with a sine-wave test-tone recorded at 0 dB reference level in the frequency range to be amplified for that set of channels (50 Hz for subwoofer channels, 1 kHz for a midrange application).
Flexible Input Section And Active Crossover Network: The JL Audio HD amplifier provides a flexible input section and a comprehensive crossover network to fine tune your system effectively and accurately. The variable filter design employed in the JL Audio HD amplifier crossover sections allow you to seamlessly switch slopes, easily change filter frequencies and address what frequencies the preamp outputs will pass. The HD900/5 offers the following independent crossover adjustments for the front, rear, and subwoofer channels along the unit's front panel, behind a removal cover plate.
- Input Mode: This switch allows operation of all five amplifier channels with only one pair of input signals (2ch); with independent front and rear input signal pairs (4ch); or with discrete front, rear, and subwoofer signal pairs (6ch).
- Input Voltage: This switch allows you to choose between using a low-level input signal (200mV-8V) or high-level input signal (200mv-2V).
- High-Pass or Low-Pass Filter: The HD900/5 has three individually adjustable filter controls for the Front, Rear, and Subwoofer channels. The Front and Rear filters are high-pass filters (attenuate low frequencies), while the Subwoofer channel filter is a low-pass filter (attenuates high frequencies). For each filter, you can select from a shallow (12dB/oct) filter slope or a more aggressive (24dB/oct) slope.
- Filter Frequency: This control selects the frequency at which each high-pass or low-pass filter begins to attenuate the signal and refers specifically the frequency at which output has been attenuated by -3dB. You can select from 50-500Hz.
- Infrasonic Filter (subwoofer only): The Infrasonic Filter is a 24-dB/oct high-pass filter, with a fixed cutoff frequency of 30Hz. This filter is designed to conserve amplifier power and protect subwoofer systems, without audibly degrading the subwoofer's bass output.
Power/Ground/Turn-On Plug: The amplifier features a Power/Ground/Turn-On plug which detaches from the amplifier to make connecting your power, ground, and remote turn-on lead wires more convenient. Once your connections are made the Power/Ground/Turn-On connector simply plugs into the amplifier.
- Power and Ground: The JL Audio amplifier's set-screw Power and Ground connections found on the detachable Power/Ground/Turn-on plug are designed to accept 4 AWG power wire. A hex-wrench is supplied for making connections.
- Remote Turn-On: The JL Audio HD amplifier's set-screw turn-on lead found on the Power/Ground/Turn-on plug will accept 18 to 12 AWG wire. A hex-wrench is supplied for making connection.
Note: The Amplifier is not equipped with a fuse. An external 60-amp AFS, AGU, or MAXI fuse (not included) must be installed on the power wire. If a wiring kit is used which includes a fuse with a value other than 60-amps, the original should be replaced with a 60-amp fuse
Speaker Output Plugs: The amplifier features three Speaker Output plugs (Front/Rear/Sub) which detach from the amplifier for easier speaker wire connection. Once your speaker wires are connected to these plugs, they simply push into the amplifier. The front and rear speaker output plugs feature four set-screw terminals, while the subwoofer speaker output plug features two set-screw terminals. The HD900/5 amplifier's ten set-screw speaker terminals found on the Speaker Output plugs will accept 16 to 12 AWG speaker wire. A hex-wrench is supplied for making connections.
Preamp Inputs: The amplifier features three sets of differential-balanced RCA jack inputs (Front/Rear/Sub). The amplifier features a dedicated Input Sensitivity gain control for the front, rear, and subwoofer channels of the amplifier. These controls are designed to match the input sensitivity of the HD900/5 to the specific signal source that is feeding it. The amplifier's input level can be set independently for the front and rear channels to Low (200mV-2V RMS) when connecting the amplifier to a low-level preamp signal or set to High (800mV-8V RMS) when connecting the amplifier to a high-level speaker signal.
Remote Level Control: The amplifier features a standard telephone connector for adding an optional wired remote level control. With the addition of the optional wired Remote Level Control (136HDRLC, sold separately), you can control the volume of one or both channel pairs of the HD900/5 form the front of your vehicle. This is useful for subwoofer level control or even as a master volume control for your system. If desired, multiple HD amplifiers can be controlled from a single HD-RLC controller using a simple phone line splitter and multiple phone cables (all sold separately).
Note: All inputs and outputs are located on the rear side of the amplifier to make installation of the amplifier simple and neat.
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