I thought I would post my experience with this relatively new product that I installed it in my 2007 S model. Sorry I don't have pics, but there really isn't anything to show that hasn't been shown many times on this forum already! You just need knowledge of the x9331 connector, the fuse panel, and how to get to each. That info is well documented in this forum.

First of all, this amp is a new version of an amp that Alpine has made for a while now. The original (KTP-445) was made specifically for Alpine Head Unit owners to add more power to their system and was an easy 'plug and play' install. The new version is a universal unit that allows install to any head unit, but still is MUCH easier to install than a regular amplifier. The ease of install is mainly because it is very small and can be tucked under the dash easily. Also, because it is a Class D Amp, it is incredibly efficient and requires little power so you do not have to run a power lead to the battery, it will run just fine off of the radio power circuit! It adds 45W per channel RMS to all four channels. THAT IS ABOUT TRIPLE THE OUTPUT OF THE BASE HEAD UNIT!

Second, let me fill you in on my system so far. It is a NON HARMON KARDON base model stereo. THIS INFO MAY NOT APPLY IF YOU HAVE A HARMON KARDON SYSTEM. I have Focal IS 165 components in the front. They are Focal's easy to install 'Integration Series' speakers and their entry level product. They are about $300. In the back I installed some Polk Audio 6x9's, around $120 or so... I also put in 'Peal N' Seal' for some Audio dampening and have found it to work quite well. The only other thing I have done is the 'Chanel Swap' that is well documented on this website. Thank you to all those who posted the wealth of info on changing speakers, Channel Swapping, and more on this forum!

Now for the amp... It will take line level and speaker level input, but as many of you know the easiest way to do this is to tap into the speaker level signal at the x9331 connector by cutting the leads to and from the harness and running them to and from the amp. When wiring the amp, keep in mind that the factory head unit does not send frequencies under 100Hz to the rear speakers, so many on this forum have performed the CHANNEL SWAP, if you don't know what this is do a search on here and you will be enlightened! Basically I flopped the front and rear output of my amp to keep the channel swap intact. I must make sure for those who haven't done their homework to NOT CUT ANY OF THE WIRES THAT ARENT SPEAKER WIRES! There are I think four wires that will stay connected to the x9331 connectors. I think they are a large brown, 2 small browns, and a white... Do a search on here for x9331 connector and you will see where it is and see many diagrams on the wire colors. This install is easy compared to installing many amps, but it does take some common sense, and maybe a little background in car electronics. ALSO, I must stress, DO NOT CUT THE LEADS IF YOUR MINI IS STILL UNDER WARRANTY! My car is WAY out of warranty and I was comfortable with cutting into those wires the way I did because I know that I can always go back and fix them later. You can also 'piggyback' the leads using taps but I chose to cut them from the harness and solder the leads together for a better connection.

After tapping into all of the speaker inputs and outputs, I ran a ground to a nut just below the bonnet release latch. Any good bare metal spot will suffice for ground. Next, the power wire was run along the firewall through the back of the center console, and behind the top of the carpet over to the fuse panel on the passenger side. I purchased a "add-a-circuit- fuse holder form the parts store (Autozone, etc) for about $7. You will also need about 4 feet of wire ( I think it is 12 guage) to extend the amp's power lead. I crimped the extended power lead onto the "add-a-circuit" power lead. I then pulled the Radio Fuse, put the "add-a-circuit" in the radio spot and put the fuse into the "add-a-circuit". The amp is just secured up under the dash with zip ties. BE SURE NOT TO OBTRUCT THE BRAKE PEDAL, OR ANYTHING ELSE THAT WOULD AFFECT CONTROL OF THE CAR! Also, no need to worry about the amp heating up, class D circuitry runs very cool, and will not be a problem with ventilation.

The setup of the amp is easy, there are dip switches on the amp that tell it speaker or line level, in this case we want speaker level. There are also High pass and low pass filters on the amp, I bypassed all of the filters for now and it is running full range. If I get a little powered sub for the back, I will change it to cut the bass under 100Hz. I also had to turn down the input gain to the amp some. Default setting was at halfway, I turned it down to about 1/3 of the way.

This amp REALLY SOUNDS GOOD! Especially for the money. Before my system was harsh sounding because there wasn't enough power to control the speakers. Now the system is very musical and has dynamics. Some people may poo poo this little amp because it isn't some high end amp for competition. For most people that love music but don't want to make heavy mods you your car, at the very least do the channel swap, put new speakers in the front's and buy this little amp. Putting speaker in the rear helps, but considering the amount of work involved I would say do that last.

Next I need a powered sub, I am looking at the Sound Ordinance Powered sub mentioned on this forum. It looks like an easy install as well!

 

Great write up. I've had my eye on this gem of an amp. For the money, it's worth using until I finally decide how to build my dream system...and if it works well enough, I won't have to bother!

 

I recently purchased a Kicker Bass Station 11PT10 powered sub so I could finally get my MINI's stereo finished. Or at least as finished as it's gonna be. Here's an update for all who may be interested.

I reconfigured the Alpine amp to only drive the Focal Components by bridging it into 2 Channel mode which doubles the output to 90 Watts/channel. The rear speakers are now being driven by the radio only and used as rear fill. I can barely hear them now, which is fine, because I have realized that rear speakers will never sound good in the factory locations. The airspace around the rears make the speakers 'tubby' sounding, this is why MINI decided to cut the frequencies below 100Hz to the rear speakers. I did have the 'channel swap' on my front and rears, but I put it back to factory configuration since I was just using the rears for fill. My phone calls now come through the fronts again! I also set up the little Alpine amp to cut off frequencies below 60Hz to the fronts.

Now on to the Sub... This sub is really nice sounding and fits beautifully in the boot. It has PLENTY of output, especially for the MINI. I set the crossover on the sub to go all the way up to 120Hz.





Some quick notes on the install...

I took out the carpeted panel on the left side of the boot (where the accessory port is) to gain access to a ground point and to tap the power port for the 12V remote turn on. This is also where you can use a fish tape to fish the power speaker wires up through the trim at the bottom of the driver's side door. I then tapped the speaker wires off of the front speaker leads at the x9331 connector.

I couldn't confidently tap another fuse at the fuse panel like I did the alpine amp, so I continued to run the power cable past the x9331 connector, over to the fuse box and out the firewall by the battery compartment. There is a nice little grommet you can go through right by the cabin air filter. It is easiest just to go ahead and take the battery out of the compartment so you can get to the cap that covers the grommet easier.

I am extremely pleased with the sound of my MINI now... Here's a quick rundown of the purchases I made for the upgrade.

Alpine KTP-445U amp $150
Focal Integration Series IS 165 $300
Kicker 11PT10 powered sub $250
Polk Audio dxi690 $120
Total $820

A couple of notes...

If I had it to do all over again, I probably would not have replaced the rear speakers. It is a considerable amount of work. At the time it was a needed improvement of the rear speakers. But since they are just being used for rear fill, I would leave them as they are and switch them only after everything else is done, assuming you can even hear them!

I was regretting purchasing the Focal speakers for a long time. I felt like I could have found a component set that sounded just as good for less money. BUT, since I bridged the amp and have plenty of power going to them now, they sound phenomenal!

The sub disconnects very easily if I need to free up space for a bit.

 

Great write-up DS! Where exactly did you find the 12V remote source in the left boot? Got any pics of the accessory port and which wires to tap? Thanks.

 

Thanks!

I just tapped the power port's 12V lead on the back of the harness. I think it is the red and black wire, it's the one that goes to the center of the power port. I just ran the remote turn on wire for the powered subwoofer (usually blue) and used a piggyback wire tap. It's pretty convenient because the ground is one of those threaded bolts that are connected to the body panel. And the Power port is right above. Leaving only the main power and speaker leads to run to the front of the car. I had to add a little wire to the end of the speaker leads to make it all the way to the x9331 connector. That would be my only complaint about the install is that those wires from the Kicker's harness are a little short. If they are short for a mini, they have go to be short for a lot of other cars!

One more note I just thought of... The Kicker Sub has two modes. One mode where it is SUPPOSED to use DC Offset from the speaker leads to sense current and turn on, and the other where it uses the 12V remote turn on lead. There is a switch on the side of the sub to select which mode you want to use. I could not get the DC Offset mode to work. The Kicker manual says it senses 6.5V from the speaker leads when the radio is on... The mini only puts out about 5.5 volts so I don't think it was enough for the sub to kick on. It's OK though, using the remote turn on lead is a little more legit anyway.

After listening some to the system today I might get back in there on the Alpine Amp and cut off the fronts at 80Hz. They try to pop just a little at high volumes. Overall, I am EXTREMELY pleased with the sound. The sub is really impressive. It is not going to rattle your neighbor's houses, but it sounds great in the car and has decent punch to it.

Now, what is my next project? I think decals!

 

i have a mini coupe with regular stereo system. mini now overs for coupes an alpine system. i cost 630 parts and 400 labor. is this a good system is it worth the money?

 

I haven't heard anything about it. Other than the base model, I've only heard of the Harman Karden system. I would be though that it is overpriced.

 

Great write up. Am installing the alpine amp and have done channel swap. Have installed infinity two way speakers in doors and clarion tweeters in b pillars. Question, why not tap into speaker wiring AFTER the connector instead of before and after? Thanks.

 

I cant remember exactly. I think it was an issue with 'slack' in the wiring and/or physical space after the harness. There's not much extra wire to mess after the harness where there is a little wiggle room for adding connectors and such before the harness.

Also, if you are adding the amp, the channel swap is no longer needed. I cut the factory wiring (remember, I'm out of warranty anyway) and used spade (male and female) connectors before and after the harness. I set up the usage of the male and female connectors so if I sell the car and want to keep the amp I just get under there, pull the amp and connect the male to the female on the factory wiring and it's back to stock, it just wont go through that harness anymore.

I attached a quick sketch to see what I mean on the terminal connectors, I hope it helps.

***Remember if you bypass the harness like I did only bypass the speaker wires, leave the power wire running through the harness!***

Even though I have just radio power running to the rears, I still put the terminal connectors on it, that way, I can run that amp in four channel mode and hook it up to all four without much hassle if I so desire. If you only want to bypass the harness for the front speakers that's totally OK too. I honestly don't think it's possible to make the rear speakers sound very good in the cavity they are in. It just sounds tubby. I would just run radio power to them or just disconnect completely and put nice power to the fronts with the amp in 2 channel mode. I've been quite happy with the setup I have now.

 

thanks very much!



QUOTE=digitalsabre;3817992]I cant remember exactly. I think it was an issue with 'slack' in the wiring and/or physical space after the harness. There's not much extra wire to mess after the harness where there is a little wiggle room for adding connectors and such before the harness.

Also, if you are adding the amp, the channel swap is no longer needed. I cut the factory wiring (remember, I'm out of warranty anyway) and used spade (male and female) connectors before and after the harness. I set up the usage of the male and female connectors so if I sell the car and want to keep the amp I just get under there, pull the amp and connect the male to the female on the factory wiring and it's back to stock, it just wont go through that harness anymore.

I attached a quick sketch to see what I mean on the terminal connectors, I hope it helps.

***Remember if you bypass the harness like I did only bypass the speaker wires, leave the power wire running through the harness!***

Even though I have just radio power running to the rears, I still put the terminal connectors on it, that way, I can run that amp in four channel mode and hook it up to all four without much hassle if I so desire. If you only want to bypass the harness for the front speakers that's totally OK too. I honestly don't think it's possible to make the rear speakers sound very good in the cavity they are in. It just sounds tubby. I would just run radio power to them or just disconnect completely and put nice power to the fronts with the amp in 2 channel mode. I've been quite happy with the setup I have now.[/QUOTE]

 

Why is the channel swap no longer needed? The amp is boosting the signal but the signals from the head unit are still bass ackward. If I bypass the connector (which is channel swapped) shouldn't I revers the front/rear wiring from amp to speakers?






[/QUOTE]

 

you stated in earlier post that you did this (swapped at amp) to retain the channel swap.

 

The channel swap was no longer needed because he wanted the bass response on the front not the rear speakers. That's how it's set up from the factory. Most people do the swap to get more bass from the rear.

I've seen a similar amp by Clarion on Crutchfield for around the same price. And for those not interested in cutting wires, Mikey at newministuff has a plug in harness with RCA outputs. Plug n play.

 

No need to swap.
The problem with the OEM HU rear output is low power and not the "bass cut-off at 100Hz" that have been written here in NAM. That is a myth based on my experience.
I also have the Alpine KTP445U married with OEM non-HK. The front and rear of the OEM were connected to the front and rear speaker level input of the Alpine.
The front & rear speakers were connected in parallel and now powered by front channels 1&2 of the Alpine KTP. The rear channel 3&4 of the Alpine KTP went to my self-powered sub. The gain setting at 9:00 position.
IF the "100 Hz cut-off in the rear output of OEM" is true, my subwoofer would have sounded terribly poor but was not the case.
This set-up keeps the fader function of the OEM still useful.

 

I installed the alpine amp per your very helpful instructions and it sounds great. But now my alarm/beep/ding dong sound is VERY loud. Somehow the amp is magnifying the warning buzzer and I don't know how to control/lower it. Your thoughts?

 

it's the "acoustic signal" that has gotten much louder since I installed the amp. I went to the radio menu that allows you to adjust the volume of the acoustic signal but it doesn't help.

 

should not affect the warning sounds/chimes...check the wire connections again.

 

Please elaborate. How can the wiring cause this when it is wired correctly (the amp and radio are functioning properly) and the acoustic signal is louder.

 

I am also puzzled. can you try to take power out of the KTP amp by taking out fuse and check if acoustic signal tones down?

 

I'm sure it will but that does not solve the problem. I'm going to start by lowering gain on the amp. If that doesn't work I may simply run the fronts with the amplified head unit rear channel and run the rears with the head unit front channel (no amp).

 

I solved the problem by lowering the gain on the rear speakers. Perfect now.

 

Right now I have channel swap with the alpine amp in 4 channel mode with gain at zero for rear oem speakers and infinity reference in front plus clarion tweeters in A pillars. Front gain set 50 percent/12 o'clock. I'm happy with it but wonder if i'd be better off with no channel swap, bypassing amp for rears and setting amp on 2 channel. What do you think?

 

2 channel or 4 channel use in the Alpine KTP will still be 45W rms per channel (at max). Why waste 2 x 45W if your intent is to run in 2 channel mode?
As I have said, the rear speakers are longing for more power to drive them. The oem radio has very low rear output that some here in NAM misjudged it as 'rear cuts off at 100Hz'.
Mine is at 4 channel mode but using this set-up:
OEM Front L/R --> Front L/R input Alpine KTP445U --> F/R Speakers in parallel (L/R).
OEM Rear L/R --> Rear L/R input Alpine KTP445U --> input MTX RT8PT Powered Subwoofer.

If you want your sound system to come alive, a powered sub is a must.

 

Has anyone ever had success in replacing a HK factory amp with an aftermarket one...In a R56? I cant seem to find anything on that subject.. If anyone cant point me in the right direction that would be great!! Thanks!

 

The rear low cut notch filter is very real on my '12 S hatchback w/boost stereo. You're lucky they didn't do that on the '04.