Comments on: Why Do We Need Powerful Subwoofer At Car?

By: Massage Cushion

Massage Cushion — Mon, 18 Oct 2010 17:27:23 +0000

the best car amplifier that i used is made by ALPINE,*–

By: Auw Jimmy

Auw Jimmy — Fri, 13 Aug 2010 16:28:06 +0000

Nice choice bro…

By: Skye Hussain

Skye Hussain — Thu, 12 Aug 2010 11:23:27 +0000

i always bought Pioneer car amplifiers because they are of very good quality and the price is great too:’~

By: Clark Johnson

Clark Johnson — Tue, 17 Feb 2009 15:54:47 +0000

Thanks Jimmy for your reply.

I shall follow it.

By: Jimmy Auw

Jimmy Auw — Tue, 17 Feb 2009 13:58:12 +0000

Hi,
Never tried 1876, only 1875. But you can use single supply as shown on the application datasheet.

I dont prefer to use equalizer. It will be better to use preamp than equalizer.

Thanks.

By: Clark Johnson

Clark Johnson — Tue, 17 Feb 2009 13:31:50 +0000

Thanks Jimmy, now its very clear to me.
I read earlier abt switching step up transformers but I had no idea that they produce inferior sound.

Now I already have with me, LM 1876 (20+20 watts stereo).
I also have an (18VDC 4 ams) transformer with me from my 14″ old TV set.

1) My question is can i use LM1876 with single supply application circuit as shown in national’s data sheet, with my above transformer??

2) Secondly i also want to build a stereo graphic equalizer with sony’s cxa 1352A ic.
will it be a good idea to pair it with LM 1876??

Also do i need to make any pre amplier with it ??? If yes kindly suggest how to place
the pre amp circuit, i.e. between equilizer circuit and power amp or before equalizer circuit.

Please reply
Thanks.

By: Jimmy Auw

Jimmy Auw — Mon, 16 Feb 2009 14:30:05 +0000

Hi,
Basically, in most car amplifier, we will use switching power supply (most likely, it’s a DC-DC Step Up power supply). So we will create higher voltage, based on 12VDC supplied by car’s battery.

I think you can figure out the rest. We can have higher voltage, so bigger power amplifier wont be any more problem.

And also, most car power amplifier are D-Class Amplifier design which have very high efficiency at minimum cost. So producing at least over 100 RMS wont be a big problem here.

For home usage, you can try to use LM IC (like LM1875, LM3875, etc). But it’s preferable to use symmetrical power transformer, with + and – voltage (switching power supply used at car will cost you the sound quality, so avoid it a home). Such IC above can be used with 15 to 25VDC (+ and – supply voltage).

Thank you.

By: Clark Johnson

Clark Johnson — Mon, 16 Feb 2009 14:14:59 +0000

Hi, Jimmy i regularly read posts in your blog and sometimes its a grt help brushing up my knowledge in audio.

I have one question with regards to the above post relating car woofers.
How could 12volt DC car battery provide enough power to such huge woofers???
Whereas we always find that one needs to use 25 to 35 volts of power supply for getting 30-50 watts of RMS power.

Hence how can I design for my home use, to get 30 watts per channel of rms power with just 12 volts 3amp transformer to get audiophile type sound with, lets say, a typical class AB type IC.

Kindly suggest!!

Good regards,
Clark

By: Jimmy Auw

Jimmy Auw — Fri, 09 Mar 2007 14:44:33 +0000

My mistake, it should lower the impedance.
Thanks.

By: Nam Nguyen

Nam Nguyen — Fri, 09 Mar 2007 03:48:13 +0000

in that paragraph you say to wire speakers in PARALLEL for a higher final resistance…what the hell??