North American Turbocoupe Organization



aftermarket speaker question
turbobird Offline
Member
#1
Is there a resistor or other component(s) to make the 4 ohm aftermarket speakers work with the 2.5 ohm factory premium sound system so that it doesnt sound like shit?

------------------
Jerry Rutten
88'Turbocoupe
Jerry R.
88'Turbocoupe
Reply

segfaultxr7 Offline
Posting Freak
#2
Are all your speakers aftermarket units, or are you running a few combined with factory speakers? In this case the impedance won't really make a difference. The only time an impedance difference will hurt sound is if you're using speakers with a lower impedance than the amp is rated for; they will draw too much current and cause distortion.

What you're probably hearing is the improved speakers bringing out the weaknesses from the stock amp. The "premium" system really isn't. Any aftermarket headunit would put out cleaner sound with more power than the factory setup.
88 TC 5-speed
Reply

tylerport Offline
Senior Member
#3
By lower impedance, do you mean 4 ohms is lower than 2.5 ohms?

I tried using some small speakers from my Home Theater System (8 ohm speakers) in my truck (with a Factory Ford Radio) and it sounded horrible. I then installed some old Ford speakers I had, and it sounded great.

------------------
Jim Portteus
NATO Member
86 Turbo Coupe, 131K Miles, 140MPH Speedo, Gillis Valve, 2 1/2" Downpipe to 2" Duals w/ 18" Glasspacks, 245/50R16's and new paint.
Jim Portteus
Reply

segfaultxr7 Offline
Posting Freak
#4
No, the lower the number of ohms, the lower the impedance. So 4 ohms puts a lower current draw on the amp.

When you tried those 8 ohm home theater speakers, the Ford radio probably was not able to put out enough power to run the speakers effecively. Even the small home theater speakers are typically made to handle at least 50 watts RMS. The trade-off is that they don't work too well under very low power, like the 4 watts or so that the Ford radio puts out. So I'd imagine you had the radio turned most or all of the way up to get decent volume, and it distorted because of that.
88 TC 5-speed
Reply

Liquid_force Offline
Senior Member
#5
Cool, a subject I actually know something about!

Here's the deal. Let's say the stock amp puts out 10 watts/channel at (2.5 ohms? I didn't realize the stock speakers were 2.5 ohms, but anyway...). When you put a 4 ohm speaker speaker on that amp it's seeing 37.5% more resistance, therefore a 37% drop in power output. There aren't many speakers built today that will sound very good being powered with 6 watts.

A resistor in parlell would drop the load that the amp sees, the problem with that is then the resistor would see the gained wattage, not the speaker.

I'd say just get yourself a decent after market head unit. They'll give you 15-20 watts per channel and should produce pretty nice sound from just about any quality speaker. As far as I know any standard din sized hu will install very easily, I know mine did.
88 TC -- Dark Blue 283k
RIP - 9/22/07
She was a great TC and went down swinging Smile
Now -- Me: A minivan, I'll spare you the details.
Her: '09 VW Tiguan AWD 2.0T 101k
Reply





Users browsing this thread:
1 Guest(s)



Theme © iAndrew 2018 - Software MyBB