Aftermarket horn wiring

[svxcess]

I am considering replacing my stock horns with the Stebel TM Magnum 80 electromagnetic horns. They are rated at 139db. The website is here with an available sound clip:

http://www.stebel.it/stebel/index.htm
(Click the products link, then the electromagnetic link, then the TM80 Magnum link)


Anyway here is my question: Since our stock system already has a horn relay in the circuit, can I just use the existing wiring to connect to the + terminal of the horns and run wires to ground from the - terminal on the horns? Or do I need an additional relay?

The horns are rated at less than 12A. The horn and brake circuit in the SVX is fused at 20A. Should I add an additional inline fuse?

According to the FSM, our horn switch provides the ground when depressed. Any help is appreciated.

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[Suby Fan]

did i read that right? 24 volts?

[Earthworm]

I read 12A@24V. Wouldn't that mean 6A@12V for the pair?

139db is at only 4" from the horn

[svxcess]

Originally Posted by Earthworm

139db is at only 4" from the horn

True, but they also measure 115db at 2 meters (over 6 ft.) from the source.

I had a tech at my favorite stereo shop measure the sound pressure of the stock SVX horn at 6" from the horn, using a db meter. It measured 97db.

That being said, remember that the decibel scale is logarithmic and therefore the sound pressure doubles for every increase of 3 points, i.e. a horn with 115 dB is approximately six times as loud as a stock 97db SVX horn.

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[Earthworm]

I understand how db works. I just find it silly to measure it at 4". Most db readings I see are at 1 meter from the source.

[svxcess]

But a sharp guy like you should be able to answer my original questions.

And if the stock SVX horns measure 97db at 6" (with the hood open), what is the sound measurement at 1 meter with the hood closed?

In any case, these have got to be louder than what I have. They measure 3.3" x 3.5" x 3.5" each.

And they can be gotten for only $18.95/pr., plus shipping, from HornsPlus

http://www.hornsplusauto.com./

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[Trevor]

Originally Posted by svxcess

I am considering replacing my stock horns with the Stebel TM Magnum 80 electromagnetic horns. They are rated at 139db. The website is here with an available sound clip:

http://www.stebel.it/stebel/index.htm
(Click the products link, then the electromagnetic link, then the TM80 Magnum link)


Anyway here is my question: Since our stock system already has a horn relay in the circuit, can I just use the existing wiring to connect to the + terminal of the horns and run wires to ground from the - terminal on the horns? Or do I need an additional relay?

The horns are rated at less than 12A. The horn and brake circuit in the SVX is fused at 20A. Should I add an additional inline fuse?

According to the FSM, our horn switch provides the ground when depressed. Any help is appreciated.

.

As no one else has been of assistance. --- Yes you can simply substitute the horns for the OEM items. Connect the same terminal on each to the original positive and ground the other. Horns with separate terminals insulated from ground are not polarity sensitive and can be connected either way, but if they are marked use the appropriate terminals.

The horns as a pair are rated, 12 amps at 12 volts and 6 amps at 24 volts, not an excessive current drain and in line with OEM.

[Landshark]

Originally Posted by svxcess

And they can be gotten for only $18.95/pr., plus shipping, from HornsPlus

http://www.hornsplusauto.com./

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you can get the same crap at you local PepBoys/Advance Auto/etc. for the same price without paying shipping.

just get some Hella Supertones for a few bucks more, and make them drop the damn cell phone when you honk.

[svxcess]

Originally Posted by Landshark

...just get some Hella Supertones for a few bucks more, and make them drop the damn cell phone when you honk.

I already have a brand-new pair of the 85115 Hella Supertones. After having them for more than a year, I still have yet to find any location where they will fit easily. They are 5" in diameter each and 2.5" thick.

Any suggestions?

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[Landshark]

Originally Posted by svxcess

I already have a brand-new pair of the 85115 Hella Supertones. After having them for more than a year, I still have yet to find any location where they will fit easily. They are 5" in diameter each and 2.5" thick.

Any suggestions?

.

remove the grille and mount behind there? i can't remember how much room is back there .....

[svxcess]

If you replace either the stock waterfall or the 97 grille with aluminum mesh, you can do this. With the stock grilles in place there is NO room.

[Earthworm]

Originally Posted by Trevor

The horns as a pair are rated, 12 amps at 12 volts and 6 amps at 24 volts, not an excessive current drain and in line with OEM.

The tech info page is confusing. If you double the voltage you double the current at the same resistance. You're looking at 6A max for the pair @ 12V. (7.2A @ 14.4V)

[Trevor]

Originally Posted by Earthworm

The tech info page is confusing. If you double the voltage you double the current at the same resistance. You're looking at 6A max for the pair @ 12V. (7.2A @ 14.4V)

\

Yes I agree that the specification is rather confusing but again examine the way things are set out.

The horns sold for 24 volt operation will most definitely have a winding of twice the resistance. The power required i.e. watts will be the same for 12 V and 24 V. When the voltage is doubled the current is halved to provide the same power requirement (watts).

[Earthworm]

Yes for power to remain the same if you double the voltage you must half the current.

I was running the assumption the same model was used for both 12V and 24V operation.

1 more thing I will point out though, if you double the voltage and half the current you must quadrouple (not double) the resistance.

[Trevor]

Originally Posted by Earthworm

Yes for power to remain the same if you double the voltage you must half the current.

I was running the assumption the same model was used for both 12V and 24V operation.

1 more thing I will point out though, if you double the voltage and half the current you must quadrouple (not double) the resistance.

I agree and the specs have caused us double the trouble.