PDA

View Full Version : RE: 2 Ohm vs 4 Ohm Speakers



ope126
14-12-2008, 08:24 AM
Hi All,

One for all the car audio experts out there...(I know it's not a VW but would apply to all manufacturers.)

Looking to upgrade the factory speakers in the Sportivo to the following;

Front: 6x9's JBL GTO937 100 watt RMS 94dB 50Hz-21kHz

Rear: 6x9's JBL GTO937 100 watt RMS 94dB 50Hz-21kHz

http://www.jbl.com/car/products/product_detail.aspx?prod=GTO937&Language=ENG&Country=AU&Region=EUROPE&cat=MEL&ser=GTS

They run 6x9's front and rear.

Basically I want to run them off the factory head unit, I will NOT be using an Amp in this set up. I have spoken to the place that will be installing these speakers (not selling them) and they advised that some OEM head units do not work on 2 Ohm Speakers.

Now, on the JBL site it mentions;

True Four Ohm - GTO speakers can be safely driven by any head unit.

However the spec's state the following;

Impedance: 2 Ohm

So my question is, are they 2 Ohm or 4 Ohm speakers?

Will they run off the OEM Toyota Bluetooth mp3 head unit?

Does anyone have first hand experience with these speakers?

I trust the above all makes sense...?

Glenn

Bubu
14-12-2008, 10:03 AM
I had a look at the website. I believe they are 2ohm speakers. It is rather confusing the way they advertise their products.

You can run 2 Ohm speakers off a factory head unit. However I must warn you that it will cause the amplifier in the head unit to work harder. Which means the head unit will get hotter. This all depends on how loud you crank up the volume. If you like your music loud then dont be surprised if the head unit fails after a while.

ope126
14-12-2008, 11:11 AM
I had a look at the website. I believe they are 2ohm speakers. It is rather confusing the way they advertise their products.

You can run 2 Ohm speakers off a factory head unit. However I must warn you that it will cause the amplifier in the head unit to work harder. Which means the head unit will get hotter. This all depends on how loud you crank up the volume. If you like your music loud then dont be surprised if the head unit fails after a while.

Thanks for your feedback.

I have sent an email to the Australian distributor of JBL, I await there reply.
I will attempt to contact them on monday also.

As for the seller (Strathfield / Ryda) they both say they are ok to use.
As for the installer (autObarn) the question the fact of using them off the standard head unit.

I guess I need to wait until monday...

Spyda
14-12-2008, 12:25 PM
Why don't you hook it up and see what happens.
Either way they will run shiz off a stock head unit. You would be better off getting a head unit and running stock speakers. If the head unit is shiz the sound from even the best speakers will be shiz.

It will work fine.

Mr İharisma
14-12-2008, 01:25 PM
Don't bother with the 2ohm speakers off a factory deck. A factory deck is lucky to put out about 15WRMS @ 4ohm 0.5%THD. Now by halving the impedance you will squeeze a little extra out of the sources amp however this is not going to double the power.

Now because you are running the equiv of an 8inch round speaker, you will want as much control over the woofer as possible. By halving the resistance, you will also half the damping factor.

So in a nutshell, you will make them sound like crap off the factory unit for very little increase in output ( possibly 1-2db ) when compared to a 4ohm unit. If you where running it off an external amp, it may be a different story. Power is not everything.....

HOLEIN1
14-12-2008, 11:41 PM
why not just get some 4 ohm speakers and save yourself the trouble?

can think of heaps of brands which offer a 6x9 in a 4 ohm configuration, are reasonably priced and probably sound better than the JBL gear...

hate to state the obvious here, something's telling me ive missed something :???:

silvershadow
15-12-2008, 08:54 AM
why not just get some 4 ohm speakers and save yourself the trouble?

can think of heaps of brands which offer a 6x9 in a 4 ohm configuration, are reasonably priced and probably sound better than the JBL gear...

hate to state the obvious here, something's telling me ive missed something :???:


The only reason I can think of for the installation of 2ohm speakers is for installations involving multi-speakers on the same channel. You can install 2 x 2ohm speakers in series which will give the same impedance and thus loading on the amplifier as a single 4ohm speaker.

I am uncertain what effect this has on sound quality but I suspect it would result in some degradation.

Mr İharisma
15-12-2008, 05:20 PM
The only reason I can think of for the installation of 2ohm speakers is for installations involving multi-speakers on the same channel. You can install 2 x 2ohm speakers in series which will give the same impedance and thus loading on the amplifier as a single 4ohm speaker.

I am uncertain what effect this has on sound quality but I suspect it would result in some degradation.

Not really. 2x 2ohm speakers are exactly that. It will just mean you will have to drive 2 coils. When you have 15WRMS on tap, running 2 of anything is not a good idea.

Bubu
15-12-2008, 06:42 PM
Dont trust Strathfield, Autoarn too much. I have seen some of their work and I must say its poor. I am sure there are many good installers out there that do work for Strathfield and Autobarn but the work that I have seen done to my mates cars has been poor. I even had to fix up their stuff ups because those installers couldn't do it right the first time.

The sales people will tell you just about anything to sell their products. Most of them are just 'sales' people and dont have that much knowledge about car audio. Again there are a few sales people that really know their stuff. But I have often spoken to some and they had no idea about anything other than the advertised specs on car audio.

ope126
16-12-2008, 07:18 AM
I spoke with a technical rep from JBL Aust. (Convoy) today.
He advised that they will be fine off the standard head unit.
They sell thousands of these speakers every year without any dramas...

I guess I should be ok?

silvershadow
16-12-2008, 08:59 AM
I spoke with a technical rep from JBL Aust. (Convoy) today.
He advised that they will be fine off the standard head unit.
They sell thousands of these speakers every year without any dramas...

I guess I should be ok?


He would say that wouldn't he????

I suggest you go talk to a specialist independent sound system installer - perhaps a home theatre specialist. They would have the same experience as a car sound system installer and you can "pick their brains' with a clear conscience if you tell them you are independently checking advice you have been given about a car system.