Impedence question

[throwoff]

Really quick question, I read the thread about impedence and think I get it but want some confirmation before I spend my money!

I am looking at the following set up -

Genze Benz Shuttle 3 going into Focus 2x10 and Focus 1x15 cabs

The head is 300W at 4ohm through one speaker out.
The cabs are both 300W 8ohm cabs.

If I take the cable from the head, into the 2x10 then from 2x10 to 1x15 I will be putting a 4ohm load onto the head and then get the full 300W out of the rig right?

[icastle]

Yep

[throwoff]

[sup][font=tahoma, geneva, sans-serif][font=arial, helvetica, sans-serif][size=3]But that is in series right? ie only using one out from the head?[/size][/font][/font][/sup]

[throwoff]

ignore me! worked it out, the amp does have parallel outputs.

[icastle]

Nope.
Your 'in' and out' sockets on the 2x10 are wired in parallel.
The amp output goes into the first cabinet and is simultaneously fed to the speakers in that cab and the 'out' socket.

[throwoff]

ah cool, so I can do it either way, the head has parralel outs as well I have since discovered only one is a speakon one is jack.

[icastle]

[quote name='throwoff' timestamp='1330527710' post='1558879']
ignore me! worked it out, the amp does have parallel outputs.
[/quote]

Well that gives you two choices

Either run two leads from the amp head to the two cabs or daisy chain them as we were talking about earlier.

Electronicaly, the amp won't care which method you use - it'll see a 4Ω load either way round.

Practically, I prefer to run two seperate cables from the amp so if one should unexpectedly fail whilst I'm playing I'll still get an output of some description - I've never had that scenario but I don't see the point in not allowing for the unexpected.

[icastle]

[quote name='throwoff' timestamp='1330527802' post='1558881']
ah cool, so I can do it either way, the head has parralel outs as well I have since discovered only one is a speakon one is jack.
[/quote]

Well the most likely point of failure is going to be the jack output.
It's quite easy to pull a jack out while shifting things about whereas a Speakon can't be removed accidentally.

On balance, if your cabs use Speakons then I'd be more inclined to go down the 'daisy chaining' route and take advantage of the more robust Speakon connectors.

[hamfist]

[quote name='icastle' timestamp='1330528355' post='1558891']
On balance, if your cabs use Speakons then I'd be more inclined to go down the 'daisy chaining' route and take advantage of the more robust Speakon connectors.
[/quote]

Definately.

[chris_b]

You can't go wrong with 2 8 ohm cabs into a 4 ohm amp, but why are you buying these cabs? Do you have a deal or have you found them cheaper somewhere?

[throwoff]

I just fancy a 210 + 115 set up and have a deal lined up.

Still might go for a Streamliner 600 and the Focus 410 but want to try both options. (the Streamliner will only put 375W into the one cab so not much net power loss and I do like the sound of 15''s)

[chris_b]

In my opinion the STL 3 would be underpowered for the cabs you're looking at. The STR 600 would interest me much more with the 210 and 115.

Have you tried this rig? I used 15's for 20 years but now I use 12's and 10's. You'd be surprised how much bass you can get out of 2 210's.

[flyfisher]

[quote name='icastle' timestamp='1330528355' post='1558891']
On balance, if your cabs use Speakons then I'd be more inclined to go down the 'daisy chaining' route and take advantage of the more robust Speakon connectors.
[/quote]
Agreed. The other advantage of speakon cables is that they can't be mistaken for instrument cables. I'd like to see the use of jacks disappear completely from cabs and amp outputs.

[icastle]

[quote name='flyfisher' timestamp='1330595241' post='1559833']
Agreed. The other advantage of speakon cables is that they can't be mistaken for instrument cables. I'd like to see the use of jacks disappear completely from cabs and amp outputs.
[/quote]

I've slowly but surely been going through all the band gear and adapting it to Speakon - just got the monitor amp and a couple of wedges to go and we'll be totally changed over.