2
While not strictly a 'new' product, they are the latest to come to Oz from the design labs
This review of the 4- channel HD600/4 is going to be in two parts
- now, the specs, pics and first impressions.
- next, listening...
Specs (from JL Audio Web Site): http://www.jlaudio.com/
Quote
Description: Class D Four-Channel Full-Range Amplifier
Patented Technology: Single Cycle Control™ (U.S. Patent #6,084,450*)
Differential-Balanced Input Topology: 2 pairs of inputs
On-board Crossover: State-variable, 12 dB/octave Butterworth or 24 dB/octave Linkwitz-Riley, Low-Pass or High-Pass for each pair of channels
Speaker output connections: Accept up to 12 AWG wire
+12V and Ground connections: Accept up to 4 AWG wire
Rated Power (4 Channel Mode): 150 W RMS x 4 @ 1.5 ohm-4 ohm (11V-14.5V)
Rated Power (Bridged to 2 Channel): 300 W RMS x 2 @ 3 ohm-8 ohm (11V-14.5V)
THD at Rated Power: <0.03% @ 4 ohm per ch.
S/N Ratio: >110 dB below rated power (A-weighted, 20 Hz - 20 kHz noise bandwidth)
Frequency Response: 6 Hz - 30 kHz (+0, -1dB)
Damping Factor: >300 @ 4 ohm per ch. / 50 Hz : >150 @ 2 ohm per ch. / 50 Hz
Input Range: Switchable from 200mV-2V RMS to 800mV-8V RMS
Dimensions (L x W x H): 10.74 in. x 8.29 in. x 1.93 in. : 273 mm x 211 mm x 49 mm (Width Measurement Includes Plugs)
Patented Technology: Single Cycle Control™ (U.S. Patent #6,084,450*)
Differential-Balanced Input Topology: 2 pairs of inputs
On-board Crossover: State-variable, 12 dB/octave Butterworth or 24 dB/octave Linkwitz-Riley, Low-Pass or High-Pass for each pair of channels
Speaker output connections: Accept up to 12 AWG wire
+12V and Ground connections: Accept up to 4 AWG wire
Rated Power (4 Channel Mode): 150 W RMS x 4 @ 1.5 ohm-4 ohm (11V-14.5V)
Rated Power (Bridged to 2 Channel): 300 W RMS x 2 @ 3 ohm-8 ohm (11V-14.5V)
THD at Rated Power: <0.03% @ 4 ohm per ch.
S/N Ratio: >110 dB below rated power (A-weighted, 20 Hz - 20 kHz noise bandwidth)
Frequency Response: 6 Hz - 30 kHz (+0, -1dB)
Damping Factor: >300 @ 4 ohm per ch. / 50 Hz : >150 @ 2 ohm per ch. / 50 Hz
Input Range: Switchable from 200mV-2V RMS to 800mV-8V RMS
Dimensions (L x W x H): 10.74 in. x 8.29 in. x 1.93 in. : 273 mm x 211 mm x 49 mm (Width Measurement Includes Plugs)
unlike some 'other' brand full-range class D amplifiers (which are rated at 1% distortion), these power ratings are at 0.03% distortion
The signal-to noise is 110dB below rated power.. hmmm, we'll hear more about that later..
Price is currently RRP $1,199.
The distributor in Australia is Custom Car Sound and can be purchased through you local car audio specialist (as listed on the Custom Car Sound web site), or JB Hifi.
There are no officially supported online retailers for JL Audio in Australia.
on to the pics...
first look - the packaging
DSC02169_2.jpg 64.46K
23 downloadsBox looks nice, inside is what you'd expect (the amp and a book and packaging), plus some extras.
DSC02170_2.jpg 68.85K
17 downloadsHere we have (clockwise from top left) the allen key set (3 sizes), The power and speaker terminals, The feet and the feet's attaching screws.
DSC02175_2.jpg 56.92K
21 downloadsAllen keys:
The smallest is for the speaker terminals
The middle one is for power wiring and to remove the control panel cover
The large one is for attaching the feet, or stacking kit (up to 3 can be stacked with the optional kits).
Power and speaker terminals:
I was a bit concerned here, JL have opted to use removable plugs for the main wiring points. This is not necessarily a bad thing, but only time will tell if the plugs are reliable.
Convenient - yes indeed; install the amp without risking the wires being bent over, or fraying as you push the strands into the hole.
No more risk of putting the screwdriver across the top of your shiny new amplifier.
Remove the amp without unscrewing (and fraying) all those pesky copper strands. Although why you'd want to remove the amp - who knows, maybe to upgrade later (more on that too).
The only negative here - with the power terminals, the clamp screws are quite large, and the allen key quite small - there is a risk of damaging the terminals or the allen key.
Also, you can't get to the screws while the plug is in the amp - the terminal must be disconnected (pulled out) from the amp to get at the allen key holes (or any 'live' parts for that matter) - Good idea I guess.
Feet and Screws:
The metal (cast aluminium) feet are coated with the same stuff as the heatsinks, and screw in from behind to allow surface mounting or flush mounting of the amplifier.
If you don't want to use the feet, the amp can be screwed directly to a board or bracket, for that 'floating in mid-air', or 'just sitting there' appearance.
On to the looks of the amp.
DSC02171_2.jpg 76.98K
17 downloadsThese amps are tiny! as you can see, it almost hides completely behind this CD cover.
don't be completely fooled by the size - they still weigh about as much as a house brick.
Solidly built, no loose parts inside, lets look at the connectors:
DSC02174_2.jpg 107.49K
12 downloadsHere we have the power socket (left), the RCA inputs and outputs (middle), the remote Level controller (right of centre) and the speaker output sockets (right).
other side - sneaky cover panel.
DSC02172_2.jpg 111.37K
14 downloadsOn the left is the power/status light, on the right is the allen key screw
panel removed using supplied allen key
DSC02176_2.jpg 84.99K
13 downloadsThe switches allow all high/low pass filter adjustments, as well as 2- or 4-channel operation.
You can select wether the bass controller operates only the rear, or all 4 channels.. interesting ideas maybe?
The pre-outs (as seen in other pic) can be assigned to front, or summed F+R output.
There is no internal fuse in the JL amplifiers, and for this model, they recommend a fuse rating of 50A prior to the amplifier.
Overall, not a 100% quality build - there was evidence of 'touch-ups' on the mounting holes and feet, like the factory just texta over any bits of missing paint in the crevasses... no big deal, but might be important to some. a light rub with a cloth restored the matte appearance just fine. Also the JL Logo on the front isn't firmly attached - I noticed this one was a bit crooked, and was able to straighten it up with my finger. Maybe a better glue there?
Next... the hookup, and listening... stay tuned.
Edited by Pulse-R, 20 January 2009 - 10:46 PM.
