I need help with setting up/understanding the ohms on PPI amp

[drwang 10+ year member]

I just found out that bridging won't work because there are 3 rca inputs on this amp. WHen i bridged it, the left channel speaker works but i don't have the rca for rear channel therefore nothing out of my right speaker. Is there a way around this?

 

[dipitydoo 10+ year member]

You will need to get a pair of rca splitters. Make sure you run it in stereo. That means the 'red' rca splits to the two 'red' inputs of the F and R channels on the amp, and the 'black' rca splits to the 'black' (or 'white') inputs of the F and R channels.

 

[DejaWiz 5,000+ posts]

You will need to get a pair of rca splitters. Make sure you run it in stereo. That means the 'red' rca splits to the two 'red' inputs of the F and R channels on the amp, and the 'black' rca splits to the 'black' (or 'white') inputs of the F and R channels.

I don't believe a splitter is needed for this amp when only using a single pair of RCA inputs for channels 1-4. "REAR INPUT" set for "INT", right?

http://ampguts.realmofexcursion.com/PPI_5440/outside2.jpg

 

[dipitydoo 10+ year member]

Hmmm, looks to be that way. If so, that would save on additional parts.

 

[drwang 10+ year member]

I don't believe a splitter is needed for this amp when only using a single pair of RCA inputs for channels 1-4. "REAR INPUT" set for "INT", right?
http://ampguts.realmofexcursion.com/PPI_5440/outside2.jpg

I had it set on ext since I have a external passive crossover. But to retain the balance, I am going to bridge one set of speakers to the front outputs, and one set to the rear outputs, then run one RCA to the front, and one to the rear, so instead of front and rear outputs, it will turn them into left and right channels.

But in terms of the int / ext feature I'm not 100% sure if it does mean whether I want to use the internal crossover or an external x-over.

 

[DejaWiz 5,000+ posts]

I had it set on ext since I have a external passive crossover. But to retain the balance, I am going to bridge one set of speakers to the front outputs, and one set to the rear outputs, then run one RCA to the front, and one to the rear, so instead of front and rear outputs, it will turn them into left and right channels.
But in terms of the int / ext feature I'm not 100% sure if it does mean whether I want to use the internal crossover or an external x-over.

I think you're misunderstanding.

Bridged, you'll still only need 1 pair of RCA inouts, Left and Right, from your HU to the amplifier. Those will be plugged into the Channels 1+2 inputs of the amp.

The external passive crossover for the comps is completely independent of the amps built in crossovers.

1. Set the Chan 1+2 XO to HP, 80Hz

2. Set the Chan 3+4 input to INT, with the XO to FULL.

3. Hook up the test leads of your DMM to the bridged outputs of the amp and set the gain.

4. Now connect the speaker wire leading from the bridged outputs to the passive xovers of the speakers.

5. There, you're all set.

 

[drwang 10+ year member]

I think you're misunderstanding.
Bridged, you'll still only need 1 pair of RCA inouts, Left and Right, from your HU to the amplifier. Those will be plugged into the Channels 1+2 inputs of the amp.

The external passive crossover for the comps is completely independent of the amps built in crossovers.

1. Set the Chan 1+2 XO to HP, 80Hz

2. Set the Chan 3+4 input to INT, with the XO to FULL.

3. Hook up the test leads of your DMM to the bridged outputs of the amp and set the gain.

4. Now connect the speaker wire leading from the bridged outputs to the passive xovers of the speakers.

5. There, you're all set.

Thanks for the guidance. Although I'm curious and still learning,... why is it that the 3+4 Channels are set to XO at Full? And 1+2 Channels are set to XO at HP? Wouldn't I want the same setting for the 4 channels?

 

[DejaWiz 5,000+ posts]

Thanks for the guidance. Although I'm curious and still learning,... why is it that the 3+4 Channels are set to XO at Full? And 1+2 Channels are set to XO at HP? Wouldn't I want the same setting for the 4 channels?

Because you're bridging and the chan 3+4 XO would be nullified. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[drwang 10+ year member]

I think you're misunderstanding.
Bridged, you'll still only need 1 pair of RCA inouts, Left and Right, from your HU to the amplifier. Those will be plugged into the Channels 1+2 inputs of the amp.

The external passive crossover for the comps is completely independent of the amps built in crossovers.

1. Set the Chan 1+2 XO to HP, 80Hz

2. Set the Chan 3+4 input to INT, with the XO to FULL.

3. Hook up the test leads of your DMM to the bridged outputs of the amp and set the gain.

4. Now connect the speaker wire leading from the bridged outputs to the passive xovers of the speakers.

5. There, you're all set.

Hey DejaWiz,

I tried your suggested settings today and the speakers didn't play any sound. I hooked up the rca's and wires as such:

Chan1+2 bridged to the right speaker and right rca hooked up to front channels

Chan3+4 bridged to the left speaker and left rca hooked up to rear channels

And I setup the XO and inputs just as you said. Please let me know if there are other things I can do to get this amp bridged. Thanks in advance.

 

[helotaxi 5,000+ posts]

Run the left RCA to the front left input and the right RCA to the left rear input. Run the left set of comps on the front channels and the right on the rear. You could geta pair of y cables, 1 female->2male, and split the left to both frontand the right to both rear if you want as well.

 

[drwang 10+ year member]

Run the left RCA to the front left input and the right RCA to the left rear input. Run the left set of comps on the front channels and the right on the rear. You could geta pair of y cables, 1 female->2male, and split the left to both frontand the right to both rear if you want as well.

Thanks Helotaxi for the response,

I tried running the RCA's as you mentioned and for some odd reason it didn't play any sound. Would a pair of those y cables work differently? Where might I be able to obtain the y cables you're talking about?

 

[DejaWiz 5,000+ posts]

Thanks Helotaxi for the response,I tried running the RCA's as you mentioned and for some odd reason it didn't play any sound. Would a pair of those y cables work differently? Where might I be able to obtain the y cables you're talking about?

How do you have the RCA's connected, the speaker wires connected, and what do you have he amp switches set to?

 

[drwang 10+ year member]

How do you have the RCA's connected, the speaker wires connected, and what do you have he amp switches set to?

Hey DejaWiz,

The right RCA is hooked up to the front channel right

The left RCA is hooked up to the rear channel left

The right speaker is bridged on front channels 1+2

The left speaker is bridged on rear channels 3+4

And the switches are as you mentioned in your post.

I tried switching the RCA's around with different combinations however no luck. I'm beginning to think it might be the amp that's the problem but it seems to function 100% otherwise. I'll try to take a picture of it and post it up. Thanks for the help.

 

[DejaWiz 5,000+ posts]

Hey DejaWiz,The right RCA is hooked up to the front channel right

The left RCA is hooked up to the rear channel left

The right speaker is bridged on front channels 1+2

The left speaker is bridged on rear channels 3+4

And the switches are as you mentioned in your post.

I tried switching the RCA's around with different combinations however no luck. I'm beginning to think it might be the amp that's the problem but it seems to function 100% otherwise. I'll try to take a picture of it and post it up. Thanks for the help.

Have you had the amp bench tested?

 

[helotaxi 5,000+ posts]

I think that you're gonna need y-cables. You want to connect the left channel inputs to whichever channel pair you're going to use for the left speaker (front or rear) and likewise for the right. The rear switch on the amp should be set on EXT and the rear x-over set to HPF. The front x-over should be set to HPF as well.