DIY PA monitor

[brcampbell]

Okay, I'm new here. I tried to search the forum, but to no avail...

I'm looking to make a few (3 or 4) monitor cabinets to go on stage with the band that I am in. Probably going to want them 16 ohm so when we wire them in series, it will work out to match our amp. Our amp/mixer puts out 300W into 4 ohms.

In any case, I'm looking for a design/walkthrough that is relatively simple and effective. The ones at guitar center that we were looking at had a 12" woofer and a horn, so something along those lines would be perfect.

Like I said, I'm new, so any points to plans, websites, books, recommendations of where and what to get etc.. that a man of average woodworking skills and electronic knowledge could hack his way through would be greatly appreciated.

I apologize if i posted this to the wrong forum, and I apologize to my wife in advance as, from what I read, this is going to be a horribly addictive habit I'm about to pick up.

[Tomac]

What impendance you need? 8 or 4 ohm?
I doubt that you'll find PA speakers with 16 ohm load. It is mostly 8 or 4 ohm, but if you use parallel-series connection, it will be easy for you to get desired impendance.
Most simple approach would , be to use 15" coaxial speakers, (Beyma, P.Audio...) in BR boxes

[pinkmouse]

16 Ohm is actually quite common in bass drivers where they are usually big horn loaded boxes that are arrayed in stacks. Drivers used in wedges are usually only 8 Ohm though, as most monitors use lots of amps each fed with a different mix for each musician.

What bare speakers are available to you, and what's your budget?

[brcampbell]

A little more clarification...

The mixer/amp that we have has a main amp output and a monitor amp output. So I'll wind up with a mono main load of 4 ohms and I'm thinking I need to wind up with a monitor load of 4 ohms as well. We're probably just going to send the vocal mix and guitars through the monitors, no bass guitar or kick drum. So my initial thinking was to have 4 monitors each with 16 ohms so I'll end up with 4 ohms total. If there is another way to do this, I'm all ears (in other words, my electrical knowledge breaks down here).

I'm looking to spend about $100-150 total per monitor (wood, speakers, etc). I know it isn't much, but until the record deal or powerball comes through (and the odds are about the same on both of those), thats what I'm working with.

I have nothing so far in the way of speakers, so a nod towards some good ones (and a reputable website that sells them) would be fantastic. I'm assuming that there are a few websites that cater to DIYers.

Thanks again for supporting my new habit.

[pinkmouse]

For guitar and vocals only, you won't go to far wrong with these Eminence drivers in 100L boxes. Fane and Bayma also do similar models.

Though a single FR driver may not seem likely in this role, they more than make up for it in simplicity and cost, with no need for tweeters or crossovers, and you can use the money you save to buy an extra amp.

Oh, and the nod:

http://www.partsexpress.com/pe/pshow...Number=290-409

[Cameron Glendin]

Hi, I just built some basic 12" neomidyum plus a 1 inch horn, the particular bass speakers operate -3 db @ 60hz 97 db @ 1w@ 1 metre in a ported 50 litre box, cost australian $250, per unit speakers/ timber / crossover US 75cents = Aust .$ 1

Light, Loud and Small, unfortunatly no idea where to get the components in the US as they are badged for an australian importer.

I have had luck with P. Audio in the past, although its a bit of a lucky dip. Cheak out their web site sometime. See if anyone has had good results with those speakers in here (they make alot!). Some of there drivers are great, some not

Cheap and in your pricerange yes

[brcampbell]

Originally posted by pinkmouse
For guitar and vocals only, you won't go to far wrong with these Eminence drivers in 100L boxes. Fane and Bayma also do similar models.

Though a single FR driver may not seem likely in this role, they more than make up for it in simplicity and cost, with no need for tweeters or crossovers, and you can use the money you save to buy an extra amp.

Oh, and the nod:

http://www.partsexpress.com/pe/pshow...Number=290-409

Thanks for the help. Those speakers look like they would be in the right price range.

So I just need a 100L box and crossovers, right? The specs said something about a high pass filter. Is there place out there that has 100L box wedge designs? I've some software that does it, but not sure if there is one for the mac.

Thanks again.

[joe carrow]

For these drivers, you would want to have an active highpass. You would acomplish that on your mixer, or you'd need an equalizer/crossover as an outboard effect.

Honestly, I think these would be quite good for your budget. If you budget was doubled, I'd suggest something with a tweeter and a crossover. $150 all inclusive is *really* tight for a monitor.

[Cameron Glendin]

Hi you can afford to do it with a horn and 1"compression driver

12" 300w driver P.aud $93 selenium $54
1" compression driver Selen $33
flare $12


crossover $15-25
mdf $15

the P audio has a slightly deeper bass smoother response both are close to 98 db 1w 1 meter so very loud!!!!!!

200 RMS watts each /2 k 12db passive xo min recomended

a USA p.audio/ selenium dealer

[Sjef]

A 100 liter cabinet for a stage monitor ? that's just silly big. For a good stagemonitor for guitar, keyboard, piano, vocals, bass etc you do not need to go lower than 80Hz except for the drumfill, in fact you do not want to go lower than 80Hz because it just causes all kinds of problems on stage without adding anything to the clarity. You will get enough low end from the main PA subs anyway. Using a 15" driver is also pretty useless because you will need clarity in the midrange and highs. Something like a 10" will do much better in this area. Also pay attention to the directiviy of the horn you will use. Remember that you want it to beam towards the musician not to the microphone in front of you. Directivity control is very important in this aspect. That's why you don't see many stage monitors with constant directivity horn in them, with directive highs you will get much more gain before feedback.

There are a lot PA forums on the net with more information on this subject. This is a Hifi forum where most people don't have any experience with sound reinforcement so many people here will give you the wrong advise although with the best intentions but stage monitoring is something completely different than a hifi setup.