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I just ordered mine on Saturday, how long did it take you guys to get yours?
They shipped Friday and got it on Saturday. When I ordered they were out of the 2x4 and I had to wait 2 weeks for it to ship. If you haven't gotten a ship notice yet it may be because they are still a little back ordered.
 

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Ok just for the record REWs auto EQ function works very well. I spent a few hours last night playing with it and wow, it's embarrassing how my speakers sounded before runnin passive and I thought they sounded great haha.

I just wanted to test a bit so I didt do everything correct but being able to play with the individual gains per channel really let me center the image. This worked way better than time alignment which didn't do much if you ask me but maybe I'm just deaf.

For the auto EQ I averaged 4-5 sweeps and had REW generate filters. Only took about 3min per speaker. I will probably reteeak everything because I'm sure there I'd more potential but seriously right out of the gate the quality and realism of my sound just went up 3 fold. Listening to the symphony soundtrack recording of the train chase scene from Mission Impossible is insane and I don't even have my sub connected yet.

I am having the ground noise issue. I'm powering it off the remote wire for my amp and have tried 2 different ground locations. Tonight I'm going to try running it off the cig lighter leads and see if it kills the noise.

Overall impressions so far are very good
 

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Interested in one of these to go active... actually two so i can go 3-way active. Only thing though, would there be any problem with using an Eclipse headunit that has 8 volt pre-amp outputs? I'm guessing I'd need a line driver to turn the signal down?

And where is that noise discussion? I really don't want a noisy piece of equipment in my system..
 

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Interested in one of these to go active... actually two so i can go 3-way active. Only thing though, would there be any problem with using an Eclipse headunit that has 8 volt pre-amp outputs? I'm guessing I'd need a line driver to turn the signal down?

And where is that noise discussion? I really don't want a noisy piece of equipment in my system..
I set the input gain jumper of a DSP to 2V and connected an 8V Eclipse 7200 to it (with no output on the DSP), played pink noise at 0dB through the USB input, and looked at the input gain meter in the software. It got very close to the top when the Eclipse volume was at 65 out of 80. By attenuating the input gain a bit through the software I was able to keep it from clipping at full volume. However, I'm not really sure what the input gain meter really indicates, it might be RMS in which case it's clipping before it gets to the top.

Here is the thread. MiniDSP discussion thread
 

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So I'd probably want a line driver to cut the signal wouldn't I? Otherwise keep the volume low. I don't think one would be necessary on the output end though, would it be? Not if the MiniDSPs were in the trunk so the signal path wouldn't be long and noisy. Or maybe it still would be, I'm not sure.

I suppose it wouldn't hurt too much to buy one of them and just go from there. If it works and doesn't have noise great! If it has troubles get them all figured out before doing anything else. 3-way front + subs can be done with just 2 boards right? I can't see why not, but people on that discussion board were saying stuff like needing two miniDSPs to run center channel + rear fill and stuff. Started cornfusing me. Just one miniDSP to mids/highs and one to midbass/subs.
 

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What kind of noise? There is a discussion elsewhere about running it on 5V instead of 12V to reduce the noise issue.
Well now at this point I don't get noise when the car is off. But I get mad alternator noise when the motor is running whether it running off 12v from the car or my laptops USB. It's loudest when running on my laptops USB and the volume cuts in half when I ground the dc ground of the MiniDSP to the cigarette lighters ground connection. I'm assuming this has something to do with my RCA connections. Ideas?
 

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Well now at this point I don't get noise when the car is off. But I get mad alternator noise when the motor is running whether it running off 12v from the car or my laptops USB. It's loudest when running on my laptops USB and the volume cuts in half when I ground the dc ground of the MiniDSP to the cigarette lighters ground connection. I'm assuming this has something to do with my RCA connections. Ideas?
The overall volume output of the music, or the volume of the noise/whine?
 

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The overall volume output of the music, or the volume of the noise/whine?
The whine noise decreases by about a half when I ground the DC input while it is connected to my laptop via USB.

I guess I'll pull the head unit out (Becker Traffic Pro) and try test grounding the RCAs to the head unit body and other places to see if it makes a difference. After some testing I'll give an update
 

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No it's a traffic pro like I mentioned made by becker. Same cd/ nav unit ferraris and lambs used to get.

Either way it's exactly what I thought. I I ground any of my RCAs to the cd players body ALL alternator noise, ticking, and hiss stops. If you're having any type of noise check this first
 

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I have been contemplating a purchase of one of these to run L(minus)R rear fill. The noise issue is really turning me off from it though.

The closest RCA signal i can get is the Aux out of one or the other of my Alpine amps (running 2-way +sub active off my 9887)

I hope you all will update with your noise issue repairs
 

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No it's a traffic pro like I mentioned made by becker. Same cd/ nav unit ferraris and lambs used to get.

Either way it's exactly what I thought. I I ground any of my RCAs to the cd players body ALL alternator noise, ticking, and hiss stops. If you're having any type of noise check this first
I've never grounded an RCA before, what did you do somehow attach a ground to the outer metal part of your rca cable?
 

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That's how it's normally done. Often one just runs a piece of copper wire off the chassis of their headunit and wraps it around the outer part of the RCA, then, depending on whether the RCAs are mounted to the headunits or if they actually have wires out the back of the headunit or whatever they figure out some way to hold it still. If the plugs are built into your headunit it's really easy to do, if they're dangling off a foot behind it's a bit trickier.

If your headunit has plugs on the back, just wrap some copper wire around them tightly and tie it to the chassis at both ends so it can't move and keeps everything grounded. If your headunit has wires out the back, you have to run the copper wire out to those wires and figure some way to tie it around them and clamp it between the headunit and the RCA plugs and that's just kinda ugly..
 

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Has anybody completely eliminated their noise issues? How many of you guys had power supply noise, vs RCA-induced noise?
 

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Has anybody completely eliminated their noise issues? How many of you guys had power supply noise, vs RCA-induced noise?
In my 95 BMW the trick was to buy a 12v to USB(5v) converter(2 bucks on monoprixe.com) to power them through their mini USB port and then ground the RCA ground back to the chassis anywhere. Killed the alternator and ticking sound I was having.

It looks like the previous owner didn't properly ground my cd chassis too so that may have been some of the cause but either way I think the USB converter is the best option for killing noise
 

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I dont know what type of cars you guys have, but i am sure Kenny is driving some kind of bimmer?

anyway...from my experience, if you have a late model bimmer or merc or any car with a rear battery configuration, make sure to pick your components carefully. They spit out a ton of interference and will induct noise from the OEM powerline/battery area directly into speaker wires, passive xover networks, even circuit boards on amplifiers!

so if the unit is not well shielded for noise, be prepared to get alternator whine that simply cannot get rid of completely.

with a more "normal" car, it should be fine, but yeah bimmers, mercs, etc really have this problem. a good way to test if you car is indeed inducting noise through the mini dsp is, if you have slack, move it close to the battery side (if you have a rear battery), as close as possible, and then move it as far away as possible, see if you detect a difference in noise level.

if you do, and in the car even at its furthest point you still get whine...well...then cap your alternator and see if that takes it away...but thats something that only helps if you had noise before...smoothing out AC ripple wouldnt wouldnt help if you didnt have noise before but have it now.
 

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I dont know what type of cars you guys have, but i am sure Kenny is driving some kind of bimmer?

anyway...from my experience, if you have a late model bimmer or merc or any car with a rear battery configuration, make sure to pick your components carefully. They spit out a ton of interference and will induct noise from the OEM powerline/battery area directly into speaker wires, passive xover networks, even circuit boards on amplifiers!

so if the unit is not well shielded for noise, be prepared to get alternator whine that simply cannot get rid of completely.

with a more "normal" car, it should be fine, but yeah bimmers, mercs, etc really have this problem. a good way to test if you car is indeed inducting noise through the mini dsp is, if you have slack, move it close to the battery side (if you have a rear battery), as close as possible, and then move it as far away as possible, see if you detect a difference in noise level.

if you do, and in the car even at its furthest point you still get whine...well...then cap your alternator and see if that takes it away...but thats something that only helps if you had noise before...smoothing out AC ripple wouldnt wouldnt help if you didnt have noise before but have it now.

Actually, the car this is in is in my daily Volvo Wagon.

From Start to Finish - A V8 Volvo Wagon


Thanks for the tips Bing. I'll probably just end up attacking this once the motor swap is done. No reason to beat my head against the wall if the noise is coming from the stock alternator, if it's going to have a new, GM alternator in when al is said and done :)
 
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