another OHM Question

[EZ9R]

I have a Crest CD2000 power amp that goes from 500watts into an 8 ohm cab, 1000 watts in 4 ohm and bridged it 2000 watts. On the back it say it goes down to 2 ohms.
My question is: having 3 8ohm cabinets, running my power amp in parallel mode, taking one output from the power amp to one cab, one output to another cab and jumping a 3rd cab from another cab, is that 2 ohms?

And how many ohms are used if I take one output to one cab, then jump the next cab and jump that cab to the 3rd cab. Basically daisy chain it.

I just got a 3rd Aguilar GS112 cab, so now I have an Aguilar stack with 3 - GS112 8 ohm cabs. I just made the switch over from an Eden 210xlt and an Eden 410xlt. So far, I like the 12"s alot.

I'm going parallel because I'm using an Alembic F1-X preamp. I also have an Eden Navigator which I can run stereo, but like the Alembic much better.

 

[bongomania]

Did you look in the FAQ?



2.67 ohms

 

[EZ9R]

No I didn't. I know this is a redundant question.
Thanks

 

[slyjoe]

That's a stereo power amp - why wouldn't you use both channels?

 

[EZ9R]

I see if running in parallel, it's 8 divided by 3 = 2.67 ohms. How do you calculate 2 running in parallel from the amp and on going series from on cab to another?

 

[EZ9R]

That's a stereo power amp - why wouldn't you use both channels?

I can with the Eden Navigator, which has 2 outs so you can go stereo or bi amp. The Alembic has 1 Full range out. If you wanted to bi amp, there is a high output and a low output and a crossover on the front.

 

[slyjoe]

You can calculate it, but it won't do you any good - your cabinets are wired parallel.

Just because you connect from one cab to another doesn't mean it is in series. It is still parallel.

 

[slyjoe]

Just because you have single output doesn't mean you can't split the signal to drive both sides of the power amp.

 

[EZ9R]

Just because you have single output doesn't mean you can't split the signal to drive both sides of the power amp.

Both attenuators work when in parallel. Channel A brings up one side and channel B brings up the other. I have a Crest LT-2000 that doesn't do that. Only channel A works in parallel, but I was using the Navigator which is a stereo preamp at the time and was using the power amp in stereo. Sorry, I'm ignorant to this. It seem all safe when it was just 2 cabs.

 

[slyjoe]

Connect two cabs to one side (4 ohms), and the other cab to the other side of the amp (8 ohms). You just need to split the full range Alembic output to feed both inputs on the power amp.

Although one side is 4 and one is 8 ohms, the amp doesn't mind and each speaker will get the same amount of power.

 

[EZ9R]

Connect two cabs to one side (4 ohms), and the other cab to the other side of the amp (8 ohms). You just need to split the full range Alembic output to feed both inputs on the power amp.

Although one side is 4 and one is 8 ohms, the amp doesn't mind and each speaker will get the same amount of power.

What would I use to split it. On cable is coming out of full range into channel A.

 

[slyjoe]

Try a "Y" cable.

 

[EZ9R]

So then I could use another 8ohm cab if I'm going stereo. Channel A using 2 8 ohm cabs and channel B using 2 8 ohm cabs that would make it 4 ohms on either side?
Thanks for you help

 

[slyjoe]

Yes, you could.

You could also put four 4 ohm cabs on each side of the amp, but you probably don't want to. I was outlining what I would do with three 8 ohm cabs.

 

[BassmanPaul]

Four 4Ω cabinets in parallel makes 1Ω not 2Ω. You can run two 4Ω loads from each channel.

Paul

 

[BassmanPaul]

Many power amp have a switch for paralleling the inputs. This means that the signal applied to, normally, channel one is also fed into channel two. This gives you the effect of having a mono amp that will have two separate speaker outputs.

Paul

 

[EZ9R]

Many power amp have a switch for paralleling the inputs. This means that the signal applied to, normally, channel one is also fed into channel two. This gives you the effect of having a mono amp that will have two separate speaker outputs.

Paul

That's what I'm doing is running it in parallel. The Alembic F-1x has 1 output for full range and it's bi-ample with a hi and low out put .

 

[IvanMike]

i used a y cable with my f1x for years with no appreciable signal degredation when used live. i think planet waves makes one you are most likley to find commercially.

why alembic does this i'll never know..........

 

[bongomania]

Right, a Y cable is generally fine for signal splitting, generally not fine for signal combining.

 

[slyjoe]

Four 4Ω cabinets in parallel makes 1Ω not 2Ω. You can run two 4Ω loads from each channel.

Paul

Of course you are correct Paul - don't know what I was thinking. Meant to type "four 8 ohms per side".