preparing my half-chang b20 build

[Spud2388 10+ year member]

Ok, i'm gettin ready to start on a pair of half changs for some pioneer b20's, but have a question. These speakers are going to be mostely for my computer, as in one to the left and one to the right of me as I sit in front of my computer and will be ran off a receiver. They will be playing 90% music. The only thing I am nervous about is how they will sound this close. I will not be able to angle them too much toward my seating position and will more than likely be aimed past my shoulders on either side. I guess it'll be about 2-3 ft from either speaker at maybe a 45* angle. Do yall think this position will sound noticeably different than sitting in a "normal" home theater layout?

The reason i am making these is because they are 1-cheap, 2-will allow me to experiment with full range speakers, 3-can be easily moved into the living room when we have parties and will provide a loud enough sound for these parties, 4- they look mean.

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[Fast1one 10+ year member]

You can't expect to get great imaging from any set of speakers being that close...more so since they are 8 inch drivers...its a sacrifice really.

With near field listening you are going to get a "headphone effect". There is no way around it....

Just keep them in the living room! Thats where I have mine...if I am ever in my room (which is rare) I just use my headphones for tunes. As soon as I want to rock out, I go to the living room...

 

[Spud2388 10+ year member]

well, this is going in a college appartment where i will spend A LOT of time in my room studying and doing homework, so I wanted something that wouldn't sound like shit (my current Klipsch 2.1) and have some output for when i needed it, ie parties. My current "setup" has the "headphone effect" and I agree with you, there is really no way around it sitting this close. But what i was asking is I have heard the half changs with the Pioneer b20's need to aimed somewhat directly at you to get the full effect and some frequencies tend to dwindle when listening at an angle. Is this true? If so, would it be better to have my desk in the corner with the speakers aiming directly at me from the ajoining walls or should i put it against the one wall and have them aimed at the opposite wall, past my shoulders?

The reason I am asking this is I am in search of a desk and cant decide if i a corner desk would be better or a regular "one wall" desk. It's pretty bad that I'm baseing my desk buying decision on how good some speakers will sound...lol.

 

[BrianChia 10+ year member]

For near field use, you'd be much better off with a smaller driver, like a 3" full range. You might have to move your desk away from the wall somewhat and put the speakers a little bit behind the desk, keeping them away from the wall and toeing in until it sounds good.

Don't put it in a corner, since you want to keep the speakers both away from the wall and far away from you and the corner just makes this really hard to do.

 

[Spud2388 10+ year member]

For near field use, you'd be much better off with a smaller driver, like a 3" full range. You might have to move your desk away from the wall somewhat and put the speakers a little bit behind the desk, keeping them away from the wall and toeing in until it sounds good.
Don't put it in a corner, since you want to keep the speakers both away from the wall and far away from you and the corner just makes this really hard to do.

yea, i agree, but then i will be losing my party speakers. i guees i'm just gonna go ahead and make these and see how they do. and if all else fails, i'll leave them in the living room, which means i'll have to make some other speakers for my computer...darn.//content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif i should be starting these after finals, which will be in a couple weeks, so ill def post some build pictures.

Another question, what kind of dampening should i put in these? pollyfill?, some other type of foam? how much?

 

[Fast1one 10+ year member]

Use egg crate foam or the like on some sides, but not all...

For example, you can do the left, top, and back side of the cabinet...you don't want to over dampen these cabinets as they work on some principles of the quarter wave theory...

You can always use some Tang Band W3-871s or Hi-Vi B3S for computer speakers if they don't work out for ya...50 dollar project tops...

 

[BrianChia 10+ year member]

Use egg crate foam or the like on some sides, but not all...
For example, you can do the left, top, and back side of the cabinet...you don't want to over dampen these cabinets as they work on some principles of the quarter wave theory...

You can always use some Tang Band W3-871s or Hi-Vi B3S for computer speakers if they don't work out for ya...50 dollar project tops...

or have seaparate pc and party speakers //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

 

[ballstothewall 10+ year member]

Way to close for an 8" fullrange driver.

 

[Fast1one 10+ year member]

or have seaparate pc and party speakers //content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

Thats what I meant //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[ballstothewall 10+ year member]

How much room do you have in the living room for party speakers?

 

[Spud2388 10+ year member]

Tts about 15 by 30 or so. Half changs are as big as i want to go. I can't haul anything bigger to school. I think they should be adequate though.

 

[Spud2388 10+ year member]

Way to close for an 8" fullrange driver.

and what do you mean by too close. Just because of the soundstage or what?

 

[Fast1one 10+ year member]

and what do you mean by too close. Just because of the soundstage or what?

Bigger drivers inherently have a poor dispersion pattern...as in they don't do as well off axis as say a 3 inch driver...
Effects tonality and sound stage when you are so close...

 

[Spud2388 10+ year member]

now, if they are aimed in at my general seating position, im pretty sure i will still have the headphone effect, but would the actual sound (tonally) sound much different than sitting a couple feet back, or is this something im going to need to determine with the actual speakers.

 

[BrianChia 10+ year member]

Tonally they would sound different because an 8" driver is going to have poor high frequency off-axis response. It will beam high frequencies pretty bad and you will lose some high end "sparkle" if they aren't pointed directly at you. You could try putting in a tweeter (such as the $10 Dayton or Aura pressfit dome) and cross it over fairly high with a 1st order high pass, adjusting the attentuation until it sounds good.