Tuning advice...

[ebumdude]

So tomorrow my MMC's will be showing up in the mail.

I will amp them to a Rockford P400-4.

I have a Kenwood DDX6029.

Any tips?? My first set of MMC's I had, they blew for some reason. So I downgraded to db6501's.

They just recently blew.

Everything is wired correctly....

Help?

Thanks in advance.

[arun1963]

Googled to find out some details on your set up and:

1. Your HU is a 2D dvd unit. Typically, dvd units are more focused on processing the 'video' signal, at the cost of the audio end. For a start, the audio signal has lower per out volts (your unit is 2 volts) than a good cd reciever (4v-5v and higher).

2. The volts on the signal from the HU largely determines where you set your amp gains. Ideally the pre out voltage from your hu should be about where you set your amp gain (i.e. around 2-3 on your amp gain). Now, turn the volume on your hu to about 80% of max. This is about the loudest you can safely play your set up. If thats not loud enough for you and you want to turn the gain up to make it louder;, you will be adding distortion to the signal. High distortion over a period of time will kill any speaker. In my set up I have a 5v output from the HU and I can hear distortion at just under 6 on the amp gain. This is when I am past my hearing prime :). Younger ears are more sensitive.

2. The Momo subs are 300watts rms each at 4 ohm. Connect the subs in parallel to show a 2 ohm load to your amp. Schematic for this is given in the subs booklet. Turn the gain down on the amp to 4. What are the dimensions of your sub enclosure? The subs are recommended to be enclosed in a sealed 0.66cuft enclosure.

3. From your Hu set the LPF for your sub at 63 and the HPF for mids at 80hz. I like to keep the subs and mids slightly apart. They focus up and blend better IMO. You can play around a bit here and see what you like. eg 63/63 sub LPF and HPF, 80/80 etc.

4. On the amp you can either AP (all pass, as you have set the xover points on the hu) or you can set the xover points here as well. Again, with a good cdr I would AP at the amp and set things from the reciever. Less variables in the signal. You may want to set x over points at the amp as well. On Your 4ch amp select HPF and set the dial to the same value as HPF on the HU. LPF value for the sub amp.

5. Your 4ch amp has a dial for eq. Play around with this so that you get the best balance in your sound. The point where mids and highs blend well and neither dominates.

Dial it in and see what it sound like. Come back with your comments. Welcome to CP.

[ebumdude]

Thanks for the input.

When I said "MMC's" I meant MMC 6501 component set for the front doors.

BUT: I took in some of your advice from step #1 and #2.

I think that the problem that I have had in the past was that there was too much distortion at high volumes that I wasn't hearing because of my subwoofers in the trunk.

Like you said, over time, they died. Both sets.

So......I turned the subs completely off, turned the volume up to about 80% and then set my gain for the front and rears. The Polk MMC6501's sound amazing by them selves. Then, I turned the subs on. Wow....I am truly impressed with the sound quality that are coming from this set vs. the DB series.

Thanks again for the info and the input. I appreciate it.

[arun1963]

Glad that it turned out well for you. I have the MMC 6500 comps bi amped to my polk 4ch amp and each driver is getting about 80 clean watts and they sound amazing. With a little TLC, your MMC's will continue to amaze you for many years.

In my post forgot to mention that you should turn the sub off when you are setting the gain, you did it the right way.

Enjoy.