Where to begin? A series of questions

[technobabble]

I've been lurking in this forum and a few others trying to absorb as much info as I possibly can before posting. I'm still a bit confused on the lingo and exactly where to put questions, so bear with me if I get a few things wrong.

I intended to build a chip amp (lm1875) that I saw in Make Magazine, and salvage some speakers out of some Palermo VA6.1s that my dad got from a white van scam for only 100 bucks (so he says). The Palermos are 1inch, 4.5 inch, and a 6.5 inch. I was thinking of building 2 boxes (left and right) with the 6.5 inchers in a box like the ones I've found here Fostex Cabinets & Enclosure Designs from Madisound and then put the 1 and 4.5 in the same box, but sealed off from the 6.5. Sort of a 2 boxes in 1 sort of thing.

In my research I've come to realize that the Palermos probably aren't even worth putting in my system even if they were free, and that I should probably start off with something new on the low end of the price spectrum. I've seen the Daytons and Foxtexs recommended around. I've also realized that I can get a 4 channel 100 watt D-class amp at Sure 4x100W @ 4 Ohm TK2050 Class-D Audio Amplifier Board | Parts-Express.com for cheaper than building a 2 channel one from scratch.

I have 2 computers sharing the same set of speakers. No surround sound needed at the moment. So here's what I'm thinkin, and don't hesitate to tell me I'm doin it all wrong. If i use the 4 channel amp linked above, I could have the subs running on 2 channels, and the tweeter/mid on the other 2 channels. Does that sound reasonable? Does the 2-in-1 box idea sound okay? Anything to point me in the right direction would be appreciated.

Now I know I'm not going to be getting any great sound, that's cool. I build cabinets, among other things, so the idea is mostly to just make a nice new work place that just happens to have speakers built into it. I'm perfectly okay with that.

[loninappleton]

Welcome the forum. To get the ball rolling, I've always been intrigued by this:

David

Bill Fitzmaurice has been authoring designs for many years and publishes in audioXpress magazine. I don't know the hookup details of the speaks in the David but it does have two build areas in one box, one facing front and woofer firing inwards on the side so these are built in mirror fashion. As a cabinet maker, a complex plan won't be confusing or hard to cut. The plan was in an older issue of Speakerbuilder/audioXpress a few years ago.

[technobabble]

Thanks for the response, I'll have a look at the design. Have any thoughts on the Palermos and the 4x100w D-class amp? Specifically whether to use 100 watts on the bottom sub, and sharing another 100 for the mid and tweeter and if the speakers are worth using?

[chris661]

Hmmmm...

A pair of "white van" speakers are unlikely to sound good next to a brand many people use. Following this, you'll likely need some better speakers. To figure out what's going to be best for you, we'll need to know the following -

What kind of music do you listen to?
What sort of SPLs?
How big is your room?
How big can they realistically be?

The idea of bi-amping (using a seperate amp for the bass and mid-highs) is a good one if you do it right.

[cuibono]

Welcome to the forum again!

As a beginner, it will make your life a lot easier if you go with someone else's design - they will have already put a lot of work into figuring out what works, and the cost of the project. There are tons of offerings around here and the web. Check out zaphaudio.com for starters.

I wish I knew that 4x100w board existed last year! That is an incredible price. I bet it performs decently, and if it doesn't, it can always be 'fixed'.

[technobabble]

Originally Posted by chris661

Hmmmm...

A pair of "white van" speakers are unlikely to sound good next to a brand many people use. Following this, you'll likely need some better speakers. To figure out what's going to be best for you, we'll need to know the following -

What kind of music do you listen to?
What sort of SPLs?
How big is your room?
How big can they realistically be?

The idea of bi-amping (using a seperate amp for the bass and mid-highs) is a good one if you do it right.

I'm in agreement with you on the 'white van' speakers probably not sounding good, but I'll start with them 'cause they're "free" and they're a standard size. So in theory, I should be able to swap them out.

As far as what type of music I listen to.. that's kinda tough. I listen to anything from classical to death metal, and video games and movies will be thrown in on the system as well. So for now "average" or something in the middle would be fine.

SPLs, if I looked up the right definition, don't have to be that loud. Again, just average. I installed crappy speakers in every room of my house including the bathroom so as to never have to crank the music to loud to hear it all through the house. (It's rather amusing to watch someone run all over the house when they get a phone call looking for a quiet room to talk in)

The room is 24x10, but the desk is going to be built in the corner 6'x6'. So one speaker is going to be facing a wall 8ish feet away, and the other is going to be facing a wall about 22 feet away. I, however, will be sitting right in between them.

The speakers can be as big as we would like them to be. This is one area where I can actually be of some use. I have just about every wood working tool I could ever need from building cabinets, that would be my only strong suit. Yesterday I went through that page and picked out a design that would be a good place to start. I chose this one: http://www.madisound.com/pdf/fostexcabs/fe166esr.pdf
I took the design specs and changed them a bit and did it up in Sketchup. For example i shortened the box from 1000mm to 900 so that I could make the sides out of one sheet of 3x5 MDF. I also changed the bottom "stair" looking part so it didn't get smaller and choke off. And I also turned that front Stair section into a speaker box for my mid and tweeter. an image can be found here: http://i38.tinypic.com/35bv4i1.jpg

Now I know ALL of these are probably going to at least moderately change the sound coming from these things, but I'm just looking for something that can put out an average sound so that's cool.

Originally Posted by cuibono

Welcome to the forum again!

As a beginner, it will make your life a lot easier if you go with someone else's design - they will have already put a lot of work into figuring out what works, and the cost of the project. There are tons of offerings around here and the web. Check out zaphaudio.com for starters.

I wish I knew that 4x100w board existed last year! That is an incredible price. I bet it performs decently, and if it doesn't, it can always be 'fixed'.

That's what I've done there as far as going with someone else's design first. As far as that 4x100, what do you guys think about how to hook that up? If I could find 2x100s for half price I would build one into each speaker, but it looks like that deal on that 4x is amazing and I'd only have to supply power in the middle somewhere.

Your help is greatly appreciated, guys. Thanks

[sreten]

Originally Posted by loninappleton

Welcome the forum. To get the ball rolling, I've always been intrigued by this:

David

Bill Fitzmaurice has been authoring designs for many years and publishes in audioXpress magazine. I don't know the hookup details of the speaks in the David but it does have two build areas in one box, one facing front and woofer firing inwards on the side so these are built in mirror fashion. As a cabinet maker, a complex plan won't be confusing or hard to cut. The plan was in an older issue of Speakerbuilder/audioXpress a few years ago.

Hi, I cannot understand how the plans could incorporate all the described possibilities, /sreten.

[sreten]

Hi,

Where to begin ? is a good question, walk before you can run, you
have some pretty ambitious ideas that can only go horribly wrong IMO.

Here are some links and keep it relatively simple at first. Rear horn loading
is for the experienced who know its exactly the sort of thing they want.

8 foot and 22 foot away simply will not do for good reproduction.

/Sreten.

Paul Carmody's DIY Audio Projects - undefinition
Zaph|Audio
RJB Audio Projects
Speaker Design Works
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Humble Homemade Hifi
Click below to go to
Quarter Wavelength Loudspeaker Design
Linkwitz Lab - Loudspeaker Design
Music and Design

[kevinkr]

Something no one has mentioned is that these speakers are for use in the near field and the OP should be looking for speaker designs intended just for this use.

[j.michael droke]

Hi there techno: Recommend you go to Partsexpress.com and look-up a book which covers basic loudspeaker/enclosure information: Loudspeaker Design Cookbook &th Ed. by Vance Dickason. In it you will get an understanding why changing dimensions of enclosure designs and removal or blocking of "shelves" designed into an enclosure is not a good idea along with the reasons that the volume of enclosures is related to specific drivers (speakers) properties (T/S parameters) and much more basic loudspeaker info. However, the book does not cover horn concepts and design. ...regards, Michael