GBMINI stereo – back to Tweeter for “do or die” repair

I am taking my MINI back to Tweeter (again) tomorrow. I plan that this is their final “do or die” attempt to get a good stereo install in my car.
They must get rid of the engine noise (which appears to be pickup through the “Monster” RCA shielded twisted pair cables which cost $100!) and I also want them to make the system sound better than the Harman Kardon was before they ripped it out and replaced it.
On the initial install they got two speakers out of phase, and “tuned” the car to have ZERO bass.
On the second visit to eliminate the engine noise, they were completely unsuccessful and for extra points swapped the RCAs to cross front & rear fade, and dislodged the radio antenna connection.
I wonder what they can do on visit three!
I also discovered today that, despite my regular comments to leave the stock wiring untouched – backed up by my running all new wiring for them to use – they decided to CUT OFF some speaker wires which I found laying in the car.
I strongly DO NOT recommend Tweeter Nashua at the moment.
MANY thanks to Dan (DanzMINI2 on MINI2) who has kindly offered to meet me at Tweeter in his HK equipped MINI so I can show them what my car used to sound like!

GBMINI stereo – Tweeter screw ups found

Back from visiting Tweeter again today.
Incredibly the installer discovered that he had crossed the feeds to two of the four speakers, so that half the sound was out of phase which is a guaranteed way to destroy the bass! I cannot believe that he made such a basic mistake and did not catch it. It appears that there was just about zero testing of the system after the install was complete.

Unfortunately I still have an engine noise through the speakers – a whistle related to engine revs, loudest around 2500-3000rpm. With the head unit volume at zero, the noise remains (it is present even when the cables from the head unit to the amp are disconnected).
Tweeter were unable to eliminate the noise. They say they contacted Boston Acoustics who claim no knowledge of similar problems.
So I am currently stuck with noise from perhaps a bad installation or perhaps a bad amp; and no-one is doing anything to fix it. I feel some strong letters coming on …

I have had some incredible advice from “Tacotim” which has helped me to understand how the “System Q” (tone) adjustment controls in the head unit work to control the sound.
Now that I have properly wired speakers, I am getting reasonable sound levels – hard to say if it is actually an improvement over the Harmon Kardon designed factory system in the car previously … I hope to be able to compare my car with a stock HK equipped car over the next few weeks (must be time for another visit to MINI Peabody.

My impression of the Harmon Kardon equipped MINI has gone up dramatically in the last week – now that it is no longer in my car. I would recommend the system to people who want amazing clarity in their car, but don’t need super loud volume and don’t mind the front sound stage setup.
Currently the $550 HK upgrade compares very variably with the $1500+ spent on my car.

GBMINI stereo – engine noise experiments

Also … some more on the stereo debacle!
I experimented this afternoon with grounding the Kenwood head unit at the Boston Acoustics amp instead of using the car wiring harness, to see if the engine whine in the speakers was due to a ground loop. But there was no improvement.
Also, disconnecting the RCA outputs at the head unit had no effect.
So it seems like the amp is picking up noise from the supply or the RCA cables – more testing needed.

The sound remains much worse than I remember the Harmon Kardon system being (only last week!)
There is significantly less bass, and the mid range is “muddy” so that vocals are indistinct.
Difficult to be more specific – but I am hoping for better understanding with assistance from “TacoTim” (on MCOL.

I plan to return to Tweeter tomorrow to see if they can eliminate the engine whine and improve any of the sound quality. But I am really extremely unimpressed with them at the moment … I was led to believe that they knew what they were doing, but apparently that is not true.