Help me pick an amp and sub

I have a couple of points for you to consider. 

First, you may be happy with the way the factory speakers sound now powered off the factory head unit.  But this does not mean you will be happy if you add an amp to them.  Most factory systems are rated at 20 watts or less, and OEM speakers generally are designed for maximum output at very low power input.  In other words, they cannot handle higher power and will not be suitable for adding an amp.  Second, on the same topic of the factory speakers, often they are low impedence drivers (2 ohms) again to try and squeeze a bit of extra SPL out of very few watts of input.  So, if you try to connect them as you describe (4 factory speakers driven off 2 amplifier channels) you run the risk of placing too low an impedence load on your amp, and could damage it.  Also, adding an amp will show up all the deficiencies in the OEM speakers, and they will sound much closer to crap than to good with higher wattage input, even if they could handle it.

You need to decide what you are really after in your truck.  From your description, it sounds to me that what you are really trying to accomplish is to make it louder and add a sub woofer.  If this is true, then I suggest you might be happier with a limited budget to simply add the sub first.  Get a good system with a dedicated sub amp that will fit into your truck.  There are some nice stealth enclosures for your GMC which will enable you to keep as much interior space as possible.  Or, you could easily add something like a Bazooka self-powered system and stay within your budget.  Then, after you save a few more $$, make a second purchase and install new speakers to replace the factory ones, and add a 4-channel amp to drive them.  If you are serious about wanting better SQ, then you will also need to replace your factory head unit, but that could be your third step.

The Alpine amp you list is a fine choice.  I also recomend US Acoustics as good quality entry-level amps.  The USB-4065 is half the price of the Alpine.

Cheers!

Clarion and MTX make good stealth enclosures for the Suburban/Yukon  that replace the center arm rest between the from seats.  The MTX Thunderform enclosure holds a single 10".  Loaded with an MTX sub and powered, they run about $350 Canadian, I believe, which may push you over your budget unless you can find one on eBay or something.  I've installed that one before and it sounds really nice.  The Clarion comes with an 8" woofer and is a bit cheaper.

I missed the bit about using your laptop as a source.  Playing MP3's?  Make sure your sound card is the best you can get and that you have the necessary output adapters, as the sound card will not have RCA outputs.   So yes, with this you will need an amp.  I suggest you use a 4-channel amp and run the OEM speakers off it, one speaker per channel.  This way you'll stay safe.  A seperate sub amp is the way to go in any case.

Here is a wrench to get thrown into the spokes. How much are you going to pay for the eq? Why are you using the computer as a source? If it because of MP3 or storage capacity or whatever, this is a highly distracting and very dangerous way to use an audio system. It is also 100% illegal to use this in Canada according to our great motor vehicle act. If you must head down this path, so be it, do it at your own and my own risk, I hope you are not on Vancouver Island, we already have enough bonehead drivers here, no offence intended.

Post up a couple of comments and lets see if we cannot get you started on a similar but safer and better path. I don't want to nix what you want to do, just need to understand what you want to do. Make sure you post up about the dollars on that eq.

spl_enterprise: I've had Memphis recommended to me before (their 5-channel amp, which ever it is). When I checked it out though, it seemed a little pricey. I'll take another look.

forbidden:

Thanks for the info on the legalities. What exactly makes it illegal though? Is it the physical pc? LCD? Because there's lots of vehicles with LCD's, DVD's, GPS etc. BMW 7-series even run Windows.  Just looking for clarification on this, as yes, I don't want to break any laws here, or put others in danger.

I will be using the computer for MP3's, DVD's, GPS, and ODB-II analysis. I'm writing the software for the interface now so that it is customized to my needs (which is keeping my eyes on the road and listening to great tunes). There will be external buttons like a stereo for controlling the music as well, so I won't have to fumble with the screen while driving. Once I load a playlist, there will be very little driver intervention.

I'm likely going to buy the equilizer on eBay. I've seen it for $50US new.

-dyno

A display that is visible to the driver that is not factory installed or for use by emergency services is deemed illegal for the most part in Canada. Law will vary from province to province. Even the RCMP vehicles with their Panaconic Youghbook laptops are highly distracting to the members, they are meant to be used when the vehicle is not in motion. Any time that it requires you to take your eyes off of the road, be it to check your infants seatbelt or play with a lcd display, you are a risk to all other drivers. Be careful if you are going to continue on this path.

Instead of an equalizer have a look at a master volume control of some kind. This will put a volume control, fade and sub level controls within fingertip reach with no driver distraction. Audio Control makes a 3.1 model that would be best for your use. www.audiocontrol.com. Buy the right piece of equipment for your needs, not the chaepest piece to do the job. This piece will make or break whatever the balance of the system will be made up of. I would also recommend a 4 or 5 channel amp to power your speakers. The factory speakers will come to life with some real power behind them. If you are after a good overall sound, the 5 channel amp route is a great way to go. If you want to annoy all those around you, then head the 4 channel amp + sub amp route. Post up if you want some more info or advice, especially on the Audio Control 3.1 route.

So does that make indash LCD's illegal too? Like those Alpine and Clarion ones?

The Clarion that I was looking at is https://www.clarion.com/usa/product/index.php?mod=details&category=processors&product=EQS744# but only with a 5-band eq. So it has fader, balance, sub and master volume control. Whether it's the same quality as the audiocontrol ones, I'm not too sure...

The Memphis 16-MC3004 4-channel amp looks very nice, and is likely at the top end of my amp budget (looks to be about $400CDN). From what I've gathered now from suggestions and other research, here's the 4-channel amps that seem to fit my application:

• Alpine MRV-F340
• Memphis 16-MC3004
• Eclipse PA5422

Any contrast/comparisons for these three amps? Or any other ones I should be looking at in the 50-75Wx4 rms ranage that I should be looking at?

Forbidden, what's your opinion on running the four factory speakers on two channels and bridging the remaining two to drive the sub?

Dyno,

I personally have experience with the eclipse amp and Memphis amp that you are considering. I have to say that both amps are excellent and will do the job, I think that the eclipse centers more on SQ while the memphis will give you a little more punch. The one thing I don't recommend is buying either amp through ebay, especially the memphis. I know for fact that if you don't buy a memphis product from a memphis authorized dealer you will never get warranty service for that product, they are extremely strict in this sense and if something goes wrong you are basically screwed. I'm pretty sure that Eclipse is the same way, I guess the point that I'm trying to make here is that you are better off buying the product from an authorized dealer. You may pay a little more but I feel that the piece of mind you recieved is well worth it.

Thanks! I hadn't heard anything specific about the Memphis yet. Since I value SQ more than SPL, I'll try for the Eclipse and see what kind of price I can get it for.

-dyno

Sorry for the late reply, PST means we get to sleep in as most of you guys are having lunch! So for replies, here we go. Any indash lcd display cannot be used when in plain sight of the driver while the vehicle is in motion. You can still use it as a cd player, am / fm tuner but not as a DVD transport to watch a movie. This also goes for an X-box or similar plugged into the screen. All of these systems usually require the use of the parking brake to be engaged. Now enterprising installers and noobs with access to a forum like this can be shown how to bypass it. This bypass and subsequent us of the lcd for viewing any entertainment source is in fact illegal in Canada and I imagine some US states. Here it will result in fines / points for driving with undue care and attention and possibly a 30 day vehicle impound, costly to say the least. Imagine a "N" driver with one of these things in his dash and he plows into you as he missed the red light, this is a chance I do not want to take, you may think that you will never do this but what about the other guy?

Now the Audio Control 3.1 will take on all comers, it is a vastly superior piece of equipment as compared to what you are looking at. It is much more than a volume control, eq, fader and sub level controller. It is also a line driver of 13volts peak and "balanced outputs". It will have a much better sound quality and capabilities in your system.

Eclipse on sale from an authorized dealer = happy customer with great sounding system, great choice, and the amp can take a high voltage input from the 3.1 as well.

Again thanks for the info. I'll look into seeing who in my area sells Audiocontrol. I don't remember seeing it at any of the shops though.

I think I'll also give the police department a call to see if I can find the laws and regulations about the LCD's. If it turns out that what you say is true for ontario as well, then I'll just have to rethink portions of my project.

-dyno