my amp

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 1:09 pm

Hello, I was just wondering why a mono amp has two terminals for subs. Like a two channel amp. I was looking at some amps and I seen that. Like the Jbl GTO1201.1 amp, it has 4 pos and negative terminals for speakers. How would you get the most out of the amp? It says minimum 2ohm on each terminal. This amp puts out most power at 2ohm.

But what if you hooked up a sub to each terminal at 2ohm would this still be full power. Because I know that you have to have 2 dual 2ohm subwoofers to make 2ohm. But this amp makes me think you could have 2 dual 4ohm subwoofers and have full power @2ohm?

fordtough1 · Post by **fordtough1** » Sun Jan 27, 2008 1:22 pm

I know the Xenon monoblocks, and I think the Ti, and RSD also, are internally wired in parallel, they put two terminals on there to make it easier on the installer.

I don't know about the JBL amp you referred to, I would assume it is the same though.

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 1:49 pm

the amp says its only 2ohm stable. So if both connections are used @2ohm wouldn't that make the amp see 1ohm if the amp is wired in parallel.

fordtough1 · Post by **fordtough1** » Sun Jan 27, 2008 5:55 pm

Yes

What is the voice coil configuration of the subs you are using?

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 7:14 pm

I am going to be using 2 dual 4ohm subs.

1moreamp · Post by **1moreamp** » Sun Jan 27, 2008 7:27 pm

When amp makers started the D class craze they used whatever speaker terminal they had laying around and that meant paralleled speaker connections inside the amp case, so if you wire two 2 ohm speakers to these terminals your load will be 1 ohm on the amp and most offshore class D amps DON"T have the outputs to handle that sort of current draw on the amp. And I am quoting Steven Mantz of ZED when I state that current draw fact of life, I just happen to agree with his point of view also after all the amps I have seen inside.

But I am hoping someday to actually see a 1 ohm D class amp that can take the punishment we like to put them though, it would be a revelation to the industry, to see one live up to its marketing....C

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 7:35 pm

oh so, the amp is 1ohm stable but it says only 2ohm stable because the amp is wired in parallel. And if someone put 1ohm on each channel the amp would fry because the amp would be seeing 0.5ohm. Is this correct?

dedlyjedly · Post by **dedlyjedly** » Sun Jan 27, 2008 8:02 pm

No, that is not correct. You can't "put 1 ohm on each channel" because that amp only has one channel. The amp has two pairs of terminals, but they're terminals for the SAME channel.

Your pair of dual four ohm subs are not a good match for that amp unless they're adequately powered by half of the amp's rated power output.

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 8:23 pm

The amp has 4 total positive and negative outputs. Yeah I know you can't put 1ohm on each, I am just wondering how it works. On the amp it says the 2 terminals you could put a minimum of 2ohm on each output. And if the amp is wired in parallel with the two outputs, wouldn't that make the amp see 1ohm?

How would you use both terminals then? The amp says its only 2ohm stable. With both outputs saying 2ohm and the amp is wired in parallel wouldn't this equal 1ohm? The manual has two subs both dual 4ohm and they are wired to 2ohm and on each output. How does this work?

1moreamp · Post by **1moreamp** » Sun Jan 27, 2008 8:28 pm

Try running two 4 ohm speaker on the terminals and you will get the 2 ohm load the maker is asking for .

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 8:32 pm

ok so if I wire two dual 2ohm subs. Wire both to 4ohms. Then when I put a sub on each terminal. The final load is 2ohms because the amp is in parallel.

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 8:52 pm

i think i got it.

1moreamp · Post by **1moreamp** » Sun Jan 27, 2008 8:53 pm

You got it !

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 8:56 pm

thank you very much.

Juice0723 · Post by **Juice0723** » Sun Jan 27, 2008 9:02 pm

ok could you help me on what subs to pick. I was looking at the phoenix gold rsd 10's & 12's. I noticed some sites say it handles 500watts rms and some others say its only 350watts rms? I have about 1100watts rms to play with @2ohms. I want to be loud.

1moreamp · Post by **1moreamp** » Sun Jan 27, 2008 9:14 pm

Hummm I will let other's answer this for you. But for my money If I buy any new woofers I am looking at the 12 C RSD speakers. These are replacing the older Elites that PG had on the market and they seem to be very impressive for the cost. just my 2 cents here, please listen to some of the others here they have more info that I do to share about this matter...C

fordtough1 · Post by **fordtough1** » Sun Jan 27, 2008 9:51 pm

I think the RSD's will handle pretty much whatever you put to them. Within reason of course. I had a single RSD Bridged on a Ti1000.2 for a while and it didn't seem to mind.

I think as long as you are smart with your gain setting, and don't clip them, they will take the power just fine.

I'm going to run 2 of them on a xenon 1200.1 in my next install, and I don't expect to have any problems with it.

That being said, I would like to try the new RSDc subs when I get enough money saved again.