[muad]

Im starting to plan my first amp and speaker rig to build. I would love your feedback and opinions!
 
For the amp I'm gonna do a class D amp from audiosector based on the LM3875 chip. I was gonna use a die cast aluminum (gonna polish it to a high shine) and a single 330va 22+22a trafo from partsexpress. Which means Im probably only gonna use one rectifier board. Im building this as a power amp to use with my audio-gd fun dac being the preamp. That will save me some money on the attenuator.
 
http://www.audiosector.com/lm3875.shtml
 
For the speakers Im kind of at loss. Im think of going single full range driver. Open baffle or boxed/reflex design. But Im not sure. I want a very balanced sound. A decently well represented frequency range. Should I run a separate powered sub. These were my choices for drivers... Im thinking 8" but maybe a 6" or a 4" would be better for what I want? What do you guys think? Also I am open to other brands also... fostex? I just want a nice full balanced sound with great imaging. Sounding natural is very important to me.
 
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-894
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=264-848

 

[nikongod]

The speaker forums at DIYaudio are much better resources than head-fi if you want to read up on speaker designs. 
 
You dont need much power for efficient speakers. Get a nice low power class-A amp for the "single driver". You only need a few watts which leaves you with many options. Gainclone, Melos SHA-gold, Luxman P1, Dynahi, etc.

 

[Uncle Erik]

Sounds like a fun project!  The Tang Band and Fostex drivers are excellent.  A couple more you might want to look at are the Hammer Dynamics speaker and the E.J. Jordan units.  Both are popular with DIY'ers.  I've been tempted to grab a pair of JX92S drivers for a long time, but I've got too many speakers around here already.

 

[sachu]

I would suggest you start with something that has already been designed and proven..learn the building techniques, experiment with established designs to understand the mechanics of speaker building.
 
As rightly pointed out by Ari, the DIYaudio forums are the place to go for this.

 

[muad]

K, ill move this over to the other forum   thanks guys, I'll post an impression when it's all done. It's gonna be slow though, school starts soon...
 
 
one question nikongod, do you think that class d with 50w per channel is too much then?

 

[nikongod]

Build the speakers first, then work on the amps. Test the speakers on a cheap reciever amp (like an old 1980's integrated amp from craigslist/second-hand-store for like $20) and go from there. This gets you speakers first so you can listen ASAP (and a nice tuner and phono stage if you play your cards right), and then you can do the easy part of building the nicer amp whenever you have time. Once you have the speakers running you can also measure how much voltage you need to run them, and figure out how much power you use from that. 
 
50w is almost certainly too much for a single driver speaker. With high efficiency speakers you rarely even need 3W, and in a dorm room I would be surprised if you used even 1/2w. You can always attenuate the signal to get it to a reasonable level, but too much attenuation is not good at all. Even if that were to work, you still have the complexity of the output filter on a class-D amp. Why deal with that when you dont need much power? 
 
An added bonus of a low-power amp in a dorm room is that your co-habitants will hopefully have a harder time destroying your speakers. Small delicate single drivers do demand a bit of respect, and someone who is not used to this and/or intoxicated may not show it... A 50w amp will make expensive dust out of the cones on many single driver speakers in about 2 seconds if you really turn it up. A 3-5W amp will make just enough noise for them to turn it down before bad stuff happens.
 
If you go with a separate sub, a class-D amp is a great idea for that application.

 

[muad]

thanks for the input, maybe ill go back to the drawing board.