how to bridge 4ch to 2ch?

[Nathan2]

Thanks guys,
Can I buy a NE5532 at Radio Shack or some other store?
or is there a place online that you recomend?






Thanks
Nathan

 

[creyc]

Digi-key's got them.

 

[clem_o]

Sound of Silence

Hi,
I feel like giving up.
I will just wait to see the posted results of placing the inverting circuit in front of one channel and then bridging the outputs of a nomal channel and the inverted channel.

I promise not to say "I told you so".

IF the phase inverter is built properly and the gain of both amplifiers on one channel is exactly matched, I reckon the result is going to be beautiful! Just what's needed for a good night's sleep...

Cheers

 

[AndrewT]

Nice one Clem😉

I even had to think about it for a while.😀

 

[Nigel Goodwin]

What's this

He posted a 'jif', as in Jif plastic lemons, as opposed to a GIF, as in Graphics Interchange Format.

I thought the Scottish would get it?.

😀

 

[AndrewT]

Hi,
at least I am consistently too slow to get them🙁

 

[clem_o]

He posted a 'jif', as in Jif plastic lemons, as opposed to a GIF, as in Graphics Interchange Format.

I thought the Scottish would get it?.

😀

Hi - Jif is a brand of peanut butter in good ol USA... (If memory serves!_

🙂

Cheers

 

[Nigel Goodwin]

Hi - Jif is a brand of peanut butter in good ol USA... (If memory serves!_

Never heard of it, but a quick google proves you are right.

The same quick google also proves me wrong!, JIF is a new graphic format I've never heard of:

JIF, JFIF, JFI - another forms of JPG (Joint Photographic Experts Group: 24-bit support and fine compression make this format another standard for publishing on the Web).

 

[clem_o]

Well now learn something new everyday! 🙂

Then again, the image posted has a GIF extension...


Nathan2 - how a bridged amplifier works: In bridge mode, two amplifiers work in tandem to drive a single speaker. This is accomplished by having one amplifier drive the speaker (+) and the the other drives the speaker (-). For this thing to work, ONE of the amplifiers (doesn't matter which one) must have a REVERSED signal compared to the other. Thus the need for a PHASE INVERTER. A phase inverter is a simple little circuit that just inverts (multiplies an input signal by -1).

If you take an amplifier system that is already bridged and add ANOTHER phase inverter , the two phase inverters working together will do this: (-1)*(-1) = +1. In other words, you get the original signal back, without any inversion. Net result - a speaker connected to the outputs of these two amplifiers whose signal outputs are EXACTLY the same produces NO NET signal across the speaker!

Hope this clears things up a bit.