Well not long ago I went from extract to All Grain brewing. It's a little more work but gives you almost full control over the types of beers you can make and what type of specialty grains you can use.
I can't say the quality increase is huge but it is better. If you want the best beer from extracts just use good recipes, great sanitation and use a liquid yeast. I did notice the improvement with liquid yeast even though you can make darn good beer with dry yeasts.
Really the difference between brewing with extracts and all grain is that instead of having the extract producer use whatever ingredients to make his wort then dehydrate it down to a syrup for you to use, you be making the work from the ingredients you choose. Depending on the maker extracts may contain a fair amount of adjuncts(corn sugar, rice syrup) and you won't know or want that. Plus you can carefully add your own choice of hops in the quantities you want at any point you want during the 1 hour boil.
In a nutshell you be buying malted barely, milling it at the shop, mashing it(adding 1 quart of water at about 170 degrees per pound of malt) and then combining in all in a picnic cooler so it will hold at between 150 and 158 degrees for 1 hour. After that time the starches in the barley will have converted to a fermentable sugar which the yeast will loving consume making CO2 and Alcohol. But that will be after an hour long boil with the addition of hops on a schedule given by the recipe and then you'll get enough experience to use you own schedule based on your tastes.
You need to sparge the grain before proceeding with the boil. All that is is slowly running more 170 degree water through the mashed barely to extract more good stuff from it. That would be fermentable sugars as well as other compounds that wind up contributing to the final beer(in taste, color, body, etc).
As a rule of thumb you use twice the quantity of water for the mash to sparge. And little less is OK since you get most of the yield before running twice that amount through the grain bed(over sparging also is bad). I use a little less because I don't have a gaint brew pot. I just sparge slowly. Instead of draining at about 1 quart per minute(recommended rate), I let the new sparge water sit for maybe 5 mins to absorb grain goodies and then drain into the brew pot.
So how exactly how is this done? The container you use to do the mash is called a mash tun. Most use a cooler and add a small system of copper tubes with slots cut in the lower half of the tubes to let the wort drain through. Wort is unfermented beer. Also you need to have the piping lay on the floor of the tun usually running out via a hole drilled and/or melted through the cooler. I seal the hole around the cooper piping with silicone since it will not intact with the wort once it's dried.
Once you've mashed and then sparged the grains to yeild the unboiled wort it's time to begin the boil. Now since most homebrewed batches are 5 gallons you won't have 5 gallons yet. So what most do is bring say 3 gallons to boil the night before in the brew pot and let it cool. That way you know you have sterilized water. Some use tap water since it should be free of bacteria but I prefer to be safe and boil that water I will be adding to the boiled wort. I do so since the wort is very susceptible to infection via bacteria. Once you've had an infected batch, having wasted all your effort, you'll want to do what you can to prevent losing another batch to an infection.
So now you start you boil(which will be 1 hour long). This is because it takes about 1 hour for the hops to have oils extracted and brought to a point via the heat where the bitterness from the hops is maximized. All beer styles have some amount of bitterness. The initial bitterness is what this part accomplishes. Hops added at various points(a hop schedule) will determine any additional flavors and/or aroma's that you'll get from the beer.
A word of caution on the boil: The Hot Break.. As the wort approaches the boiling point it will begin to foam. It fact depending on the proteins within the wort it may really get out of control and wind up boiling over and creating a huge, hot sticky mess . So to get through this point you want to start stirring the wort as it gets closer to boiling. You'll see the off whitish foam begin to start to form. This is the point that you need to manage. Keep stirring and in fact stir a little faster. This will hamper the size of the foam head that will form. If it really starts to get toward the top of the edge of the pot, blow on it and keep stirring. I have to blow pretty hard which allot of folks can't do without getting pretty light headed. Another option is to keep a spray bottle of clean , cold water nearby and spray the foam with it. It will reduce it. I have read where others throw a penny or 2 in and the head will calm down. You can also reduce the heat for a few moments. Once you have seen this, you'll know exactly what I mean. That's why I never come close to having a full brew pot. I rarely go over 3/4 full. You'll need that space to get through the hot Break. You know you're through it because the foam will slowly drop and you see the wort is boiling. Now is the time to add your bittering hops and begin timing the 1 hour boil. Adding the hops can cause a little foaming but you're through the Hot Break but keep an eye on it for at least 5-10 more minutes more just to be sure. If you ever have a boil ever, you'll never want to go through it again because of the hot, sticky mess you have to clean up.
Once you added your bittering hops just keep and eye on it for that 5-10 more minutes and stir occasionally. Keep the boil rolling but it doesn't have to be a full roaring boil. Just a steady medium boil. Let it boil for 60 minutes and shut the boil down and get ready to cool the wort(what we call the beer at this point) down to about 70 degrees. This cooling will allow proteins and other things to precipitate out so you'll end up with a nice clear beer.
I cool by adding the covered brew pot in a sink full of ice. Give the wort a stir with a sterile spoon and add more ice as the ice melts. It will take an hour of more but you need to get the wort down to around 70 degrees which is cool to the touch. Remember to cover the brew pot with a sterile lid. I just take the lid that came with the brew pot and rub it down with a little rubbing alcohol to make sure it's sterile. Trust me, this is when the wort is most susceptible to bacteria infection. Not what you want. In stead of using a thermometer, i just clean my had and rub them down with rubbing alcohol and when it's cool to the touch is ready to be put into the fermentor and have yeast pitched into it. You wont have the usual 5 gallons(average home brew batch size) so you need to add water to get to 5 gallons. So use boiled water that was left to cool overnight to be sure it's sterile but I use clean tap water. Although possible, it's unlikely to to get an infection from municipally treated water. If you use well water I would boil it for a few minutes and let cool overnight in a separate container. The water you used for the wort has gone through the hour long boil so don't worry about that.
If you ask me, if your water tastes good then it's OK for home brewing. If not, use bottled or boiled water.
More coming on this page.