I'm looking into adding some pro audio into my car.. I pretty much have everything ready except some pro audio mids. I'm looking to run them off channels 3&4 on my Arc FD 4150 and want them to get some power. The reason they need to get a lot of power vs your standard 8 ohm mid is because I'm running 2 crescendo supertweets of a Arc FD 2100 and they are screaming (see distance video below.) I'm really only looking into 1 mid per side so I can fit the supertweet and mid in a kick panel I'm planning on making.

Edited October 20, 201113 yr by AllenH427

There are some 4 ohm pa mids, the powerbass 4xl is one, I use them in my vehicle right now.

I have a pair of 4 ohm mids, the Powerbass 4xl-65-92. They have been powered once to make sure they work, if interested send me a pm.

Just a heads up to you, a driver does not need a lot of power to keep up with those crescendo's. Your gonna need mids with a higher sensitivity if you want to try and keep up with those supertweeters.

turn the gain on the tweeters down bro. I run those same tweeters and the gain on my amp is practically all the way down and I still turned them down another -3 -4 on my head unit.

8ohm PA mids will get loud as shit Mine can be herd loud and clear at full tilt!

Nothing you should worry about there really.

You lose efficiency with lower impedance not usually worth the balance. There is a reason pro audio mids are normally 8ohm or higher.

The 8" Neo Pro mids from Sundown are a great buy imo.

That just seems weird to me, a mid on 40w of power doesn't seem like it'd be as loud as a mid on 80w or even 160w for 2 ohms. That's a ton more power. Jay-cee, I'll PM you here in a bit.

A high efficiency pa mid simply does not need that 160w.

i have a set or sudnown NEOPRO 8's

on 2 channels of a sundown 100.4.. 8 ohms stereo , and i have it dialed way down ..

That just seems weird to me, a mid on 40w of power doesn't seem like it'd be as loud as a mid on 80w or even 160w for 2 ohms. That's a ton more power. Jay-cee, I'll PM you here in a bit.

How about this, which is louder. Two physically identical drivers

8ohm 97db Sensitivity

4ohm 88dB Sensitivity

Here I'll make the math easy for you.

8ohm will be 97dB at 1w

4ohm will be 88dB at 1w

Then realize that 40w to 80w is audible, but you need to double the power to hear a difference. Again there is a reason why PA stuff is 8ohm+

If a speaker has a sensitivity of 100db and a rating of 100rms, it doesnt need the full 100rms to reach a 100db or higher. It will take 100rms continuously in the right application while outputting 100db's. The ohm load of an amplifier or speaker wont make it louder at all, regardless if its a 8 ohm mid/4 ohm mid or 2 ohm mid. The higher the ohm load on a amplifier does produce more wattage but you lose efficiency as well so its a give take relationship. The lower ohm load is there on pa speakers because most people or clubs run a lot of them together so it helps wit the final ohm load.

I have put a 100 watt selenium 6w4p on a 50 watt amp, 200 watt amp and 500 watt amplifier. You couldnt hear a difference between the 50 watt and 200 watt amplifier except for some peaks that are in the music but nothing audible really. The 500 watt amplifier just made the driver distort and bottom out quicker, so hopefully my experience can help you or at least give you an understanding on how pa speakers work.

Thanks a bunch guys, I'm used to sensitivity not actually meaning something.

I'm looking into the Selenium 6w4ps. They are 8 ohm drivers as well.

http://www.arcaudio.com/archives/fd-man.pdf

Here's the manual to my amp, the 4150, page 7 is probably what you'll want to look at.

I'm thinking, if I wire the drivers in parallel, thats a 4 ohm load, and if I run them bridged on inputs 3&4, each input will be seeing a 2 ohm load. So technically, the drivers (combined) will be seeing 320 watts (80@4, 160@2.) Is this correct? I know that I'll lose left and right stage but that's okay.

Edited October 22, 201113 yr by AllenH427

Just curious why are you limited to 2 channels on you 4channel amplifier when you have the supertweeters on a 2 channel amplifier?

If you wire two 8 ohm drivers together on channel it will create a 4 ohm load, so with your amplifier each speaker will only see 40 watts. You dont want to bridge those two channels and run all your mids that way because you will loose stereo.

Thats why I asked above what are the other 2 channels on that arc 4150 powering.

Background Info:

So right now in your possession are two amps, a 2 channel and 4 channel? You have one pair of Crescendo Supertweeters? You plan on making pods for your new mids and Crescendo Supertweeters? Im assuming you have a pair of speakers (what size) in the doors already, if so what speakers?

I take it that you want some louder speakers than what you currently have in the doors and if thats the case then it would probably be best to replace those speakers in the door with whatever mids your planning on getting (granted if they can fit or your willing to do some work to your doors).

What is your budget on new speakers as well?

I have Alpine Type-X refs on channels 1 and 2 right now. I'm into SQ (not dedicated) a bit so I want to run these primarily. The with an rca splitter, run the pro audio stuff (3&4 and 2chan amp) so I can fade-in the Rear RCA output when I want the PA playing. I'm not planning on listening to the PA daily, so I don't care about stereo all too much.

Since you say your into SQ, I would try to run the new mids on their own channel (one mid on ch 3 and the other on ch 4). So you still have stereo and see how that sounds. Im pretty sure you will be fine there. But if you still wanna try them bridged on channel 3 and 4 then go ahead but you wont gain that much output and you will lose the stereo. So pretty much just get in there and test and find which suit your needs better.