series parallel switching with relay

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=90560
Printed Date: May 09, 2025 at 7:07 PM

Topic: series parallel switching with relay

Posted By: aznboi3644
Subject: series parallel switching with relay
Date Posted: February 16, 2007 at 7:52 PM

I am going to be using a couple relays for switching my dual 2 ohm sub from 4 ohms for daily chilling to 1 ohm for when I compete or show off to my friends.

How big of relays will I need to handle 1200 watts safely.

Haem...I'm pretty sure you have this neat setup in your ride...what would you suggest

Replies:

Posted By: stevdart
Date Posted: February 16, 2007 at 10:26 PM

https://www.the12volt.com/relays/page5.asp#spvr

See the above for switching from series to parallel on the special applications relays page. Compliments of the12volt.

While you know that the amperage draw from the 12 volt battery / alternator source is high, you also know that the amperage is reduced dramatically to the speaker because of the high voltage amplifier source. 40 amp relays will do the trick with room to spare. Standard 30 amp relays would do the job, too, I'm sure.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Posted By: aznboi3644
Date Posted: February 17, 2007 at 10:55 AM

Thanks Steve...I was thinking about 30 amp relays but I'll go with the 40 amp ones for some extra safety

Opinions on relays.

Which one of these is better

this or this

Posted By: haemphyst
Date Posted: February 17, 2007 at 10:56 AM

The Bosch 30A relays will do just fine...

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Posted By: haemphyst
Date Posted: February 17, 2007 at 11:53 AM

aznboi3644 wrote:

Thanks Steve...I was thinking about 30 amp relays but I'll go with the 40 amp ones for some extra safety

Opinions on relays.

Which one of these is better

this or this

For the extra 4 dollars it'll cost overall, get the Bosch relays. The reliability is worth it to me...

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Posted By: aznboi3644
Date Posted: February 17, 2007 at 8:47 PM

Alright cool...thanks haem

Posted By: splaudio
Date Posted: February 18, 2007 at 4:48 PM

i really would not recomending doing this because it will affect ur impedence. if this is for a daily then spl set up dont do it...

Posted By: haemphyst
Date Posted: February 18, 2007 at 8:31 PM

splaudio wrote:

i really would not recomending doing this because it will affect ur impedence. if this is for a daily then spl set up dont do it...

ummm... I think he wants to do this BECAUSE it will affect the total impedance. If you read the opening post, he WANTS to have a higher impedance for everyday use, and a lower impedance (and therefore, more power, thus, more SPL) for showing off...

Why is it your recommendation he NOT do this?

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Posted By: aznboi3644
Date Posted: February 19, 2007 at 2:01 AM

I also wanna know why you don't recommend this??