mcdanjw

I've seen posts on here about the resistance of the stock speakers being 1 or 2 ohms, but no one seems to be exactly sure. Does anyone know definitely?

I'm thinking about replacing the stock speakers, but don't want to replace the stock amp. If the stock speakers are 2 ohms, then perhaps I could get two sets of separates for the front, run them in parallel to drop the 4 ohm load to 2, and them build a custom enclosure for the in the door. Can anyone help?

Vector02

where in austin do you live man? We should hook it up sometime....i'm in San Marcos.

jdl75

Get a multi meter, disconnect the speaker from the amp, set the meter to ohm's (resistance on some). Place one lead of the meter to one lead on the speaker, and the other meter lead to the other speaker lead.

Then post what you find - Mine's in the shop, or I'd do it and tell ya.

SilverKnight

I was once told by my professor in an electrical class that the forementioned is not a correct way to check the impedance. It's not the speaker's resistance but rather an equivalent impedance load. I cannot remember exactly the formula and the correct way to say it so I have to stop here.
You can verify what I said (what my professor said rather) by measuring a known 4 Ohm speaker.
I think I did and I didnt get 4 Ohm out of it. I'll try it again tomorrow morning and tell y'all the result.

aaron

your professor is a moron, just kidding but i think you are confusing somethings that he said???? anyways, the factory speakers are 2 ohms for sure, but your idea of running the separates in parallel as in a 6.5" and tweet won't work(if I am understanding your idea correctly), although the mid is a 2 ohm, the tweeter is at a very high ohm load, so that it won't recieve too much power, because their is not crossover in line to reduce distorted bass. If you replace the speakers and not the amp your volume will be cut in half.

360

Hey vector02

some guys in ausitn want to have a meet if you want to come cheack teh club event forum.

[ 07-17-2001: Message edited by: 360 ]

mcdanjw

aaron,

I'm actually talking about running two mids in parallel... maybe a 6 1/2 in the door and a 5 1/4 under the console in a custom cabinet or something. I doubt I'd even add another tweeter. That would bring it to 2 ohms, and from what you're saying match the load for the stock amp. Sound like it would work?

SilverKnight

My comment was just to the method of checking the impedance. I didnt say the speakers are not 2 Ohm. btw, I checked it this morning, using the method described above and the resistance is anything but 2 Ohm nor 4 Ohm. Like I said, 2 Ohm or 4 Ohm is not the resistance, it's the impedance. If you are not convinced, look at the bottom of any speaker (not the Bose's cuz there is nothing there) and you'll see it's specified as "Imp." not "Resistance". You can verify it for yourself.

mcdanjw

Vector2.... we're planning a meet in Austin in early August. Check the club events forum. Should be fun.

I live off of Far West and Mopac in North Central Austin.

SilverKnight

Keep me posted as well ... I go to Austin once in a while. Let me know

MikeSwing

I'm also in Austin. I have a 1st gen CL but I'd love to meet you guys and see your cars. Keep me informed of the meet and I'll be there.

aaron

in car audio resistance and impedence are synonyms for each other. to answer the earlier question, yes running a 6.5 and 5.25 speaker in parallel will leave it at two ohms, but that also means your splitting the total power of the stock amp in half to power the front speakers

jdl75

We'll try this again. It's been a few years since I've delt with basic circuits (I am an engineer, with degrees in Mechanical and Electrical), so I double checked my work.

1. My above method is correct. If you do not disconnect the amp, you will be checking the impedence of the speaker-amp system, and you will get a fubar. ALL of my speakers read +/- 0.2 ohms of their rated value.

2. You are correct in your statement that impedance and resistance are two different things. Do you know the difference?

Impedance - A frequency dependent resistance to current flow; all three ideal circuit elements exhibit impedance to sinusoidal excitation in real life. This IMPEDANCE is expressed as a function of frequency in phasor notation.

Resistance - a linear obstruction to the flow of current. Not frequency dependent.

In car audio, resistance and impedence are interchangeable. The inductive resistance of the speaker (voice coil) is small compared to other resistances in the speaker. Large discrepencies would indicate a crappy speaker.

Class dismissed.

[ 07-28-2001: Message edited by: jdl75 ]

CRAZEDLUNI

Why does it say 1ohm on the bottom of my speaker's? Isnt ohm andd resistance the same thing? I'm pretty good with car audio but by no means an expert or pro. Just I see it printed 1ohms and everyone says they are 2ohms.
Thank you

jdl75

Ohm is the normal way of expressing a resistance. Since there is no real unit for impedance (impedance is a mathematical creation), and impedence and resistance is considered interchangeable in car audio, it says ohm. You may see on occasion someone that wishes to differentiate, and they will say "a # ohm impedance" or "a # ohm resistance". If they say impedance, ask at what frequency.

As for your markings, that's news to me. Either no one else has markings and is guessing, or they've changed components.

hope that helps

[ 07-28-2001: Message edited by: jdl75 ]

aaron

thanks for restating, what i just said, and i don't have 2 degrees in electrical engineering, i do this for a living, and looky their two of us agree.

garypen

Resistance and impedance are indeed two different things. A speaker's "ohm" rating is the impedance, not the resistance. You cannot measure a speaker's impedance using a simple ohm meter accross the two conductors. An ohm meter (or volt/ohm meter or multimeter) measures resistance.
It's that simple, and it applies to home audio, car audio, concert audio, studio audio, it doesn't matter.
BTW, I was a concert audio engineer for 20 years. My sound systems were comprised of 100's of speakers, usually 8 or 16 ohm IMPEDANCE. The amplifier power wasn't measured in watts either, it was measured in kilowatts. I just wanted to mentionthat so you'd know I was somewhat familiar with thye topic.

[ 08-09-2001: Message edited by: garypen ]

[ 08-09-2001: Message edited by: garypen ]

SilverKnight

I tried to tell them not to measure speakers' impedance with a regular dmm or dvm but they didn't wanna listen. one guy even said my college professor was nut for stating that Thanks for clarifying the issue.

jholland

You guys have lost me here, but what gives the better sound quality in speakers. higher or lower ohm rating. I radio installer yesterday told me that I wouldn't have to replace my bose speakers if I went with an aftermarket deck. He said that I would just need to bi-pass the existing amps and re-join the speakers to another amp. Is this true?

mcdanjw

Yes it it true. The ohms of the speaker won't have any effect on sound quality, but you need to have an amp that is designed to work with the ohmage (i guess that's a word) of the speakers you are using.

Typical car stereos are 4 ohms, and most if not all aftermarket amps are designed for that. The factory bose speakers are 1 ohm, and will fry any aftermarket amp you hook them to.

So you have to replace the speakers and amp. Sucks.

jholland

Thanks man,

technoid

Jerry,

Your installer is not telling you the real story. Believe the guyz on the forum.

BTW, mcdanjw, the term for a speaker's resistance is impedance, not ohmage.

[ 08-22-2001: Message edited by: technoid ]

mcdanjw

Brainfart!!

jholland

You guys are hilarious. I think I am going to gut the whole Bose system, and replace everything. Can you tell me what you think about the MTX Amps,Subs, and Pioneer Decks?

[ 08-22-2001: Message edited by: Jerry ]

[ 08-22-2001: Message edited by: Jerry ]

mcdanjw

I don't know much about MTX's amps, but I've had a pair of MTX 8's before. They were good speakers. I got to the point where I didn't need 20 speakers in my car, so I gave them to a friend. He's still using them today 8 years later. I think they are a good value, maybe not the flashy speaker you can buy, but for the money a good deal.

You might consider leaving the stock deck, just because I think it looks better than most of the aftermarket decks I've seen pictures of here on the board. I bet its sound quality would be comparable to a Pioneer too. Just replace everything else.

That's what I'm planning on doing as soon as my purchasing agent (wife) gives me permission.

jholland

Thanks,
I appreciate the advice.

jholland

Thanks,
I appreciate the advice.

97Blue

From personal experience, I have gone with mostly Alpine for head units. I bought a JVC years ago, and it was really what they say "Junk-Very-Cheap"... the *&%^( thing was in the shop getting fixed more than it was in the car!

Lots of my friends who've had Pioneer products are not totally impressed. Alpine seems to get good marks, along with Kenwood.

Now for amplifiers I've used Sony units before with great results. Alpine amps were a lot of money at the time and Sony offered good specs at a reasonable price.

For speakers I've used Alpine subs, Polk, Boston Acoustics and Infinity with very good results. From what I know of MTX is that they make low end stuff that gets sold at Wal-Mart and other discount chains.... not a good endorsement for the quality. I'd take a look also at JBL speakers.

Hope this helps!

SilverKnight

Can you be consistent? I said your first statement was wrong (absolutely, definately sure about it) but not the later one. I also think that's how to measure the impedance of a speaker but I don't have anything to back it up so I didn't say anything.
As fas as I know, I hold a degree in Electrical/Electronic Engineering Technology. I admit the I cannot tell impedance's definition off the back of my head but I know for sure resistant and impedance are different and I would have no problem quoting it like you did.

Peace.

[ 09-01-2001: Message edited by: SilverKnight ]