I have been watching the post here and like most of this site for me after a little while I get the itch to jump in. Here goes. I have a kenwood kac742 ( it is about 8years old but is in very good shape) that I want to setup with Polk 6 1/2 components (ex2560) in the front and Polk 5x7 (ex572a) in the rear. The amp is 4x60w. I have several questions about doing this. I think I have found a good deal for the speakers at circuit city, I can get both pair for right around $200, does this sound good? Man to install them and the amp the price went up to $740 which included an extra $120 for having them put the 6 1/2 in instead of the 5 1/2. Well I guess I will be doing it now! On with the questions:
1. Does this setup sound like it will work together? I'm not a huge audio nut, I'm looking for crisp clean sound at an average level.
2. Is it going to be that hard for me to do the 6 1/2's and will it be woth the additional hassle?
3. Is there no way to put 6x9's in the back doors? I think the bass response would just be so much better.
4. RCA convertors, do these need to be more then just something to change from the speaker wires to RCA jacks? I think I read somewhere were they need to reduce the factory HU output to minimize distortion. What would be a good choice for these?
5. Is there a power line off the factory HU that will act to turn the amp on and off?
and finally the dumbest question I'm sure. Please be kind guys!
6. The amp has two input sensitivity adjustments. I know when adjusting these it reduced or increased the sound output of the amp at a certain level. They adjust from 5v to 0.1. Can someone enlighten me on the pupose of these and how to adjust them properly?
I remember when we just grabbed a spool of dual wire and went to town. This audio stuff sure has gotten advanced, but then again so has the sound. Thanks guys for all your post that have helped me get this far.

 

Loco I will do my best to answer your questions.
First, I think the sound will be just fine, but will lack a bottom end punch since you don't mention a sub.
Second, the 6 1/2s will fit, but will take a little work to fit. make an adapter from either 2 layers of 1/4 in ABS plastic or 1/2in MDF. In my truck I used the ABS sandwiched around a piece of 1/8"in steel and wrapped in dynamat. Either way use dynamat on the adapter and the door panel if you can. This helps immensely to kill road noise and vibration.
Next, IMO you won't hear much if any different bass response between the 6x9 and 6x8
Fourth question. Yes the adapters should be more than just high to low level convertors. a good unit will keep out engine whine when converting and give you gains to adjust the output
I don't believe their is a lead for a power antenna on the back of the factory HU. It would be easier to run a line to the fuse block on a switched ignition lead though. The turn on signal uses so little power that it would be nearly nothing in whatever circuit its attached too.
Your last question is not at all dumb, but is quite misunderstood. Many times I have seen guys think the higher the gain/sensitivity is the better! WRONG! A simple way to adjust gain is this. Put the gain control on the amp at its lowest point. Raise volume until it starts to distort, then back it off slightly. Next raise the gain until the amp starts to distort, then back it off slightly. If your line level convertor has gains, simply set them B4 setting the amp. Also do the front and back seprately.
Hope this helps and Good Luck!

 

Chuck, thanks for the feedback. I purchased the convertors today and they do come with gain controls. I'm a little confused about the adjusting of the gain controls. Here is how I read it, first I want to adjust the gains on the convertors. I believe it is to put the amp on the lowest sensitivity and the controllers I assume as well then turn up the volume. Then I turn the gains on the controllers up until they just start to distort, then back off a little I assume. Then I adjust the amp input controls up until they just start to distort and then back off a little as well. My question is won't the amp start to distort immediately when I start to adjust it as above since it was distorting with the convertors giving just a little more? One more question I purchased single shielded RCA's, should I spend the extra for the double shielded or is that just overkill?

 

One more question does it matter if you put the convertor closer to the radio or the amp, do I want to use longer RCA's or shorter ones?

 

Loco,
The amp may distort a little. If it does, lower the gains slightly at the amp. The reason for for this is that the convertors are sending as much signal (voltage) to the amp as possible. the more signal the amp gets, the less likely you are to have noise. Mount the convertors in a convient location. I prefer to mount them close to the amp as it makes adjustments easier and the speaker level outs from the HU ae less likely to pickup noise. The single shield RCA will be just fine. If you do mount the convertors close to the amp, the RCAs can be very short.

 

Boy I'm glad you said that, it looked alot easier to pull the speaker wires and run them as far back and to a convenient place then try and figure out how to place those convertors under the dash and be able to get to them. I'm going to do this over the weekend I will let you know how it turns out. Thanks alot for the info.

 

Thanks alot for the info Chuck, the install went pretty smooth. The factory HU has excellent sound paired with this amp and speaker set up. You are right about the bass, this setup falls short in that area but that is the only problem I see with it. I also found two additional 5x7 factory cut-outs in the back corners of the cab that are not used. I'm going to look into if it would be possible to put 8" woofers in those areas. Thanks again for the advice.
For those reading this, there is nothing wrong with sticking with the factory HU it sounds great with good speakers and some more power.