Class D Mini Amps

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Anyone using one of the Class D mini amps like the Alpine KTP-445? They seem to be popular with bike riders who can easily fit them inside fairings.

I'd like something with a little more oomph than my head unit provides, to provide better volume at highway speeds, but have neither the need nor inclination to go though the hassle to mount and install a full-sized amp.

Given the plethora of choices now available in the category, it looks like I'm not alone.

I've narrowed it down to the Alpine, or the Clarion XC-2410, which offer more adjustability than the Pioneer and Sony units.
 
I have experience with the Pioneer GM-D1004. I used it in my buddy's VW EOS with an aftermarket android radio that really sucked sound quality wise. the nice part about the pioneer is that you can choose to connect by RCA, that gives a massive bump in SQ. If you would use the speaker output ( most mini amps only offer speaker output as line in ) the already [censored] signal gets amplified, yes it will play louder, but it won't make it sound better.

I don't know if you are using a factory headunit or an aftermarket, that makes a difference because the OEM HU probably doesn't have RCA outputs.

It definately is easy to install, within an hour with the right tools. I do advise to run a extra 12v wire as a power source for the mini amp instead of using the std delivered iso adapter. It will take the power from thesame wire as the headunit then and the factory wire isn't made for these amp draw. for these small amps i suggest to use a fuse tapper like this:

[img:left]http://contentinfo.autozone.com/znetcs/product-info/en/US/bsm/BP-HHH-RP/image/3/[/img]
 
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We installed a 500w mono Punch mini amp in my old bosses semi. I was a little underwhelmed, but for something so small and drawing such few amps it pushed a 10" sub ok. He said that he found the right setting to wake it up, but I don't think I ever heard it after that. I haven't thought to ask him how it has held up.
 
I though this was for home
smile.gif
Ive been looking at SMSL Q5 pro stuff so its digital straight through to the speaker OUTS. No Class AB to be found. You guys talking tripath? Of just wave chopper power supplies?
 
I've been using a JL Audio XD400/4 for several years now in the car, amping the fronts and bridged to the small sub in the rear. It was perfect since it was small enough to fit under the passenger's seat. No problems at all since it was purchased in 2012. I'm no audiophile, but it sounds good enough for me.

Is this for a car or motorcycle? I think regardless of what you go with, it should be an upgrade over the HU's internal amp, especially if you're pushing aftermarket speakers. If you have an Alpine HU, the Alpine amp is an easy option.
 
It's for a car with an aftermarket head unit, so I can feed it with RCA line level.

I'd just need to construct a short harness so I put it in the free space behind the center stack on top of the tunnel, and run a positive cable through the firewall to the positive jumper terminal, which is just on the other side. I think the factory radio harness could handle the lower draw models but it's tight, and not that much additional work to be assured of a proper power supply.

The Clarion is marine-rated, so it has no issues with weather. The Alpine isn't, but I don't think it's an issue, as lots of people put them in their cruisers.

Alpine was the first to market these, first as a PnP for their head units, then with a universal version. Pioneer, Sony, Clarion, and others have jumped in.

Feature comparison

What seems to be telling is that the Clarion has a 40 amp fuse, while the rest are 15 amp.
 
Yeah the Clarion would be my choice based on the specs. I don't think it will be working as hard as the others to make rated power.
 
Originally Posted By: ARCOgraphite
I though this was for home
smile.gif
Ive been looking at SMSL Q5 pro stuff so its digital straight through to the speaker OUTS. No Class AB to be found. You guys talking tripath? Of just wave chopper power supplies?


I don't know how these things work. I know the punch amp we used ran jacked up rail voltages.
 
How much power can the drivers (speakers) handle? The Clarion seems a wise choice, the only disadvantage is that it has the lowest S/N ratio, but i'll doubt you'll hear the difference in a non high end setup in a car.

I do have a higher end setup in my car ( ESX Vision Elite 6.2C MKII front components, Hertz Mille Pro 690.3 Rear ovals, powered by a Hertz EP4 amp ) and i do hear some slight noise when i listen to music with the engine off, and that annoys me..

For the clarion i would also run the wire directly from the battery, the 15 amps from the other systems would be fine from the fusebox. Make sure to use an inline fuse within a few inches of the battery
 
Originally Posted By: AVB
Originally Posted By: ARCOgraphite
I though this was for home
smile.gif
Ive been looking at SMSL Q5 pro stuff so its digital straight through to the speaker OUTS. No Class AB to be found. You guys talking tripath? Of just wave chopper power supplies?


I don't know how these things work. I know the punch amp we used ran jacked up rail voltages.
Anything with big power in a car/boat, MC needs to jack up VOLTAGE, you cant make much RMS wattage with a 4ohm speaker with 14VDC.
 
Yes, but I was comparing voltage of traditional class AB & D amps with these newer mini amps that run even higher rail voltages to get comparable power in a smaller chassis. Rockford Fosgate calls it Boosted Rail Technology or BRT.
 
I don't have experience with those smaller ones, but I was interested in those Alpine power packs for the longest time. My issue was the additional hiss if you use the speaker level version. I am very familiar with class D amps in a car and recommend them highly. I settled on the Alpine PDX and JL Audio HDs. They're nearly a decade old design and I expect them to update it in the next few years... meaning you can pick them up cheap when that happens.

If you just want more volume, you'll need more than the 45watts max that those power packs provide. The best way to 'add' more volume is sound deadening via thin neoprene sheets in your doors and thicker open cell foam carpet padding over your wheel wells in the trunk. If there is room and it's safe, even under your dash near the firewall. Doubling your wattage is an increase of 3db. So a 3db reduction in your noise floor is 'equivalent' assuming you keep the volume knob in the same spot. That's not to mention the overall enjoyment you'll get from a quieter ride.
 
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I'm well aware of the limitations, and potential issues the mini amps entail.

But they're cheap and easy enough to install that I'm willing to take a chance. And despite the premium a place like Crutchfield charges, their support and return policy minimizes the risk and is well worth it.
 
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