Hi Folks

first of all great community! i have a small problem! I got a JL HD 600/4 Amp (how small??!) JL C5 Comps and a Cleansweep. this was to replace the HiFi system in the car.

The problem is i had a really reputable company install the gear (JL Dealer) and they didnt use the volume **** that comes with the CL. I am getting loads of hiss at any volume and the JL dealer says that the signals that i get from the mini stereo are useless. he says there is nothing that i can do and i have to live with it. is it me or is this a cop out?

Cheers for any help

 

I have to laugh, I just completed an install of the exact same setup. I think I can help.

 

Ok....I have a few questions about the Cleansweep install. Would you be able to tell where they got the inputs? How did they connect the HD 600/4 to your speakers?

The short version is...if you don't use the Cleansweep volume control you need to set it at a good level that allows you to get good volume from the factory volume control, but without getting hiss, and this is very difficult to do. The Cleansweep manual says that you will get hiss if you don't use the JL volume control to manage the volume of your system.

I spent HOURS mapping the wiring to the rear amp for this project and can tell you what almost all of them do. This helped me decide how to manage this configuration.

I have not upgraded the speakers yet (Have to save some money first) but this setup sounds AWSOME. I can't imagine how good it will sound with new speakers. I'd like to know more about the speakers you chose.

So PM me or something, maybe we can help each other out.

 

I too have installed a Cleansweep. I found the instructions tell you to turn the volume on the radio to 75% or 3/4 of the way. When I tested the system I found that there was alot of hiss and the PONG! PONG! chime was extreamly loud. So I disconnected my amp and performed the the calibration test again but turned the volume of the radio all the way up. After the cal. I reconnected the amp and tested, much better on the hiss and the PONG! is more normal. ( I disconnected the amp so the volume wouldn't blow your ears out.) I also played with the treble and bass adjustments and each time recalibrating and testing. You really have to play around with it to get a good sound.

 

You just have to live with it? Excuse me, but you aught to get your money back for the install. You paid for a job done right, not a half-*** job that sounds worse than before.

 

Well, what you might have to live with is the capabilities of the Cleansweep. The Cleansweep instructions state that, for best performance you need to use the Cleansweep volume control ****. They go on to say that if you do not, that you may experience some hiss. Where your installer screwed up is in not using the Cleansweep volume control, unless of course you told the installer that you did not want to use the Cleansweep volume control. If you did, the hiss is a limitation of the Cleansweep system, in the configuration you chose. In that case yes, you will have to live with it, though you can minimize hiss by tweaking the calibration as Big K stated above.

I have to say that, using the Cleansweep volume control ****, I am extremely satisfied with the performance of my system, even with the stock speakers still in place (they are next on my upgrade list). With the HD 600/4 I am pumping 150 watts RMS into those stock puppies and, while I am sure that an aftermarket speaker would sound better, I am amazed at how good they sound and how much power they have been able to take.

 

Interesting! I was also considering getting a clean sweep. Very useful information here. I’m assuming you all used the summing interface for the Hi-fi installers? Would adding some dynamat help with the hissing?

Did you get the speaker level inputs before the stock amp or after? Did you remove the stock amp? How did you rewire the car?

This is how I had it planned out… you splice the wires (before or after the stock amp depending on how it needs to be done, preferably before the amp, and eliminate it) and you connect them to the Clean Sweep. Clean sweep rca to amp, amp speaker wired connected to spliced speaker wires. Since I was planning on getting a 3 way component then I would have to run a new speaker cable to the front doors to hook into the cross over.

Also, wouldn’t some of the hiss come from the cheap factory speaker wires not being able to handle the extra power of the new amp?

 

Don't know if Dynamat would help with hissing, I don't really see how it could.

I did not use the summing interface. It appears that the output from the factory headunit to the HiFi amp is full range so a summing interface is not needed.

I pulled the Cleansweep input signal from the harness to the amp in the boot (I will post what-wire-does-what to the HiFi amp as soon as I get the time).

I removed the stock amp entirely without any issues, no check engine light, no anything. In fact, I mounted the Cleansweep where the HiFi amp used to be. Interestingly enough, if you disconnect the X???? harness (referenced in the front/rear channel swap thread) behind the driver's side kick panel by your left foot, the car WILL NOT START and gives a check engine light (but no codes).

I used the same harness(s) (there are two to the HiFi amp) to wire the speakers to the amp I installed (I placed the amp in the useless "tool kit" space and saved the tool kit for posterity), so no rewiring needed. I investigated running new speaker wire to the doors but to do it right would require major surgery, and since I am still using the stock speakers I'm not worried about the speaker wires right now.

As for hiss from the factory wires....you got me....it's possible I guess. I get very little hiss and only at very high volume (between tracks, for example...and like I said...very little).

 

russgriz,

although you may currently not have any problem with having removed the amp entirely there is no way that Mini can now update the software in your car.

Their system will not like the fact that the amp was removed and will not allow the upgrade of software.

The reason i know this is i had also taken out the amp for some testing and found that there was a problem with some other functions of the car and took it in to have the software upgraded per Mini USA instructions. I drove the 70+ miles to the dealer and had to drive back home and get the amp and then drive back to the dealer so that the amp could be hooked back up and then the software updated. Also of note was that they could not even check some of the software problems with out the amp in the car.

So just a warning. Do Not throw that amp away and make sure if you go to the dealer for anything, bring it with you.

 

Thanks for the heads up with the amp thing. Seems the inventory car I was looking at was sold so I'm back to ordering one and that means no hi-fi. Some of these issues will be eliminated. I asked about the rewiring because I am thinking of getting the 3 way components listed in the other forum (I will buy the a pillar tweeter mount) and thought that would be best. I can alwas use one of the own wires but crappy wires could probably accout for distortion and hiss. As far as dynamat i'm no entirelly dure but I think noise dampening also includes blocking out interference and/or engine noise. Not sure tho.

 

schatzy62,

Thanks for the advice. So far, all of the cars functions continue to work without the amp (radio, CD, iPod, Bluetooth, etc.). I will be keeping the amp and, just to play it safe, I'll take it with me to the dealer should I ever need to go, though I don't understand how the amp's presence or absence could affect the car, let me explain.

I have mapped all of the wiring that goes to the HiFi amp on the driver's side in the boot. The wires all fall in to one of three categories, signal from the head unit, power and ground, and signal out to the speakers. There are no wires for data communication and/or logic circuits. It seems really fishy to me that your dealership would not be able to do a software upgrade just because the amp was missing. The only differences between the standard stereo and the HiFi one is the addition of the amp and the additional speakers. The head units are the same. The amp only serves to take the speaker level outputs from the head unit and amplify it, hence my use of the Cleansweep as a line-out converter on steroids. This being the case, every gen 2 MINI with the standard system is just a HiFi with the amp and extra speakers missing. Unless the MINI with HiFi is somehow programmed to check for the presence of the amp, I don't see how this could be a problem, or how it could tell the difference between the missing amp and my Cleansweep.

You say that there is "no way" that they could update the software in the car. Can you explain this? The software doesn't update via a port in the amp or something along those lines, so I am confused.

Just to be clear, I have an 08 MCS with HiFi and without NAV. Perhaps the situation is different if you have NAV, I don't know.

Could you tell me what sort of problems you experienced after taking out the amp? I would like to know what to look out for.

In any case I will be cautious, follow your advice and keep the amp and carry it with me to the dealer if/when I need to go, so thanks for the heads-up and for sharing your experience. I would not have gotten anywhere if it weren't for people like you who have volunteered their knowledge and experiences. Hopefully my experience will help others with their modification decisions as well.

 

russgriz,

Since the outputs from the MINI head unit are full-range (so no summing is necessary), and the head unit doesn't perform any non-defeatable equalization like the head units in some other cars, is the Cleansweep doing anything for you other than acting as "a line-out converter on steroids", as you described it?

I looked into the Cleansweep briefly, but since we don't need the equalization cancellation or channel summation for our cars, I thought that it would be better to just go with a high-quality amp that takes speaker-level inputs (like the JL Audio 450/4 v2). Is there something else that using the Cleansweep in a MINI gives you that I'm not seeing?


And for having issues with updating the car's software after removing the factory amp, schatzy62's not the first person to have that problem. The car's computer expects the amp to be present. Whether the amp is actually on the i-bus (or whatever MINI calls it), I don't know, but somehow, the car's computer knows when the amp isn't installed, and will complain when the MINI techs try to update the software.

 

The BMW diagnostics computer first examines the car configuration, and it will not perform the software update if there is a mismatch with the configuration expected according to the VIN. This includes checking for the presence of the HiFi amp. The amp might not have anything to do with the actual software updating operation.

I had a similar reaction about Cleansweep. The primary purpose of the product is to undo preset equalization in a factory head unit. Some factory head units have a preset equalization (undefeatable), tailored to compensate for cabin acoustics or factory speakers. However the MINI headunit has been measured to have fairly flat response, i.e. no equalization. If you are building up a high end audio system but want to keep the factory headunit, another reason for Cleansweep is get the flattest possible response out of the headunit. However if you are building a truly high quality system, you'd want to get the most out of it by using Cleansweep's volume control, which is a huge detraction for me.

 

I thought that head unit did have an equalization curve. The common complaint is lowered bass response from the rear speakers and hence the main reason of the speaker swap, to divert extra bass to the 6x9 that have better use of it.

Now you guys are confusing me, if this is notvthe case then an amp with high level inputs is all you need. Of course if you plan To add a sub the bass problem is a non issue.

 

The non-HiFi headunit has a low frequency cutoff filter, which has a different purpose from equalization. Equalization is for shaping the response curve across the entire range.

 

^ so the no hi-fi has a low frecuency cutoff and this is not present in the hi-fi? If this is true then the glen sweep is necesesary for a non hi-fi modification? And in a hi- fi a high level acepting amp would sufice?

 

I don't think the Cleansweep can compensate for the low-frequency rolloff. Like rkw said, that's different from equalization. I'm trying to find the thread where the rolloff was first discussed, but I remember that it's *very* steep, something like 18 dB per octave, starting around 100 Hz or possibly even a little bit higher. To recover the information in the bottom two octaves, the Cleansweep would basically have to "make something out of nothing".

I think you'd be better off just taking the full-range front outputs from the head unit and using them to drive all four channels of the amplifier. You'd lose the ability to control front-to-rear fading "on the fly" from the head unit, but you could set the it at the amp and pretty much forget about it. Plus, you'd be saving $190 by not needing the Cleansweep.

 

Scott I think you went a little technical on me, but let me see if I got it right... Basically in the non hi-fi the bass is not cut off in frecuency but in decibels much like a inverse/reverse loudness button. If this is true then I think this is where the setup in the clean sweep comes into play at 50-75% volume output where the rolloff is not in full efect, then you would probably leave the head unit **** in that setting and use the clean sweep... That's probably why they want to have you use their ****, if you do then you will loose the steering wheel controls (if you have them). Your idea makes much more sence tho, I hardly ever play with the balance/fader. Thanks for your input!

 

Basically, what's happening with the low frequencies in the rear channels of the MINI's stereo isn't equalization - it's a low-frequency rolloff.

Equalization is where you boost or cut the response in certain frequency ranges. The amount of boost/cut is usually pretty small, less than 10 dB.

But the low end response of the MINI's rear channel is actually being "rolled off" much more dramatically. At 100 Hz, the response is pretty much normal. But by 50 Hz, it's been cut by 18 dB. By the time you get down to 25 Hz, it's been cut by 36 dB, which basically means that there's no signal left to recover.

JL Audio doesn't say how much the Cleansweep can boost or cut the response when it's trying to compensate for factory equalization, but I'm pretty sure that it can't compete with 18 dB or 36 dB of attenuation. The Cleansweep might even fail to calibrate correctly, because it can detect if the outputs from the factory stereo aren't full-range, and will give you a red "fail to calibrate" light. I don't know if the 100 Hz rolloff would be enough to trigger the warning, though.

 

doesn't the rollof start at higher volumes? In any case your idea of only using the front channes sounds good, or if a subwoofer is planned one need not to bother!

 

Well, the rolloff doesn't change with volume - it starts at 100 Hz, and the response is pretty much dead by the time you get to 40-50 Hz, so you're losing most of the bottom two octaves in the musical range.

Adding a subwoofer would work as well - just make sure you use the *front* outputs from the head unit to feed the subwoofer amp.

 

thanks! Big help

 

im totally lost now lol

 

Isn't here where the signal summing of the Clean Sweep comes into play, you still loose the ability to balance front/rear in the head unit...

from the front rear swap thread:

so wouldn't the CS take the Sub 100hz from the front channel and then take the rest from the real channel and make its output signal?

 

Good point, now I'm back to square one... LOL