impedance...

[Nate]

Stupid question to some of you I'm sure...

I have a Markbass little mark 2 (older model) and 2 ebs proline cabs - 2x10 and 1x15.

The cabs are 2ohms each and the head says:
OUTPUT POWER
300W RMS @ 8 ohm, 500W RMS @ 4 ohm

I want to know if I can use both cabs at the same time... I seem to have forgotten anything about GCSE physics. :s

I appreciate any help you can give me - in English if possible!

I've tried to upload a picture of the rear panel of the amp for you.

Thanks in advance,

Nathan

[Colledge]

i've never seen a 2 ohm cab before, only ever 4 or 8 ohm cabs.
if that actually are 2 ohms then you would have to have a series cable made up so that together they present a load of 4ohms together.
if you ran these cabs normally, or even one at a time, you'd be exceeding the minimum load and could blow up your amp.

i'd have another check though because i very much doubt they're 2ohms each.

[Nate]

Sorry - what a stupid thing i've done!

They're both 4 ohms.

I had a conversation with someone about it before I typed and they'd gone on about 2 ohms something or other.

Same question but they're both 4 ohm cabs!

I'm having a slow day :s

Thanks for the reply though!

N

[Colledge]

with 2 4 ohm cabs you kind of have the same problem. used normally (a lead from the amp going to each cab) it will present a load of 2 ohms which is too few for the amp. you can run them in series to get a load of 8 ohms, but that means having to get a special speaker lead and also you won't be getting as much power out of your amp as if you have a 4ohm load.

[Nate]

Ok...

It has a "link" port on the back of the cabs - I can't go from the amp, into the first cab and link it via that to the other cab can I?

I'm probably being very very stupid.

Apologies,

N

[Colledge]

i'm not sure, if the "link" port is wired in series (power running thru 1 cab then the other) then yeah, that'll work. but if its in parallel (power devided between the 2 cabs) then no, it won't work.

[geoffbyrne]

'Link' ports are almost invariably wired in parallel. DO NOT DO THIS.

You will release the Magic Smoke if you do!

Geoff

[Kev]

Short answer, you can only use one of the cabs with the amp as things stand. You will need two 8ohm cabs if you want 2 cabs and max power from the head.

[Nate]

Thank you all!

[Pentode]

If you really want to use both cabs, then as said above, you'll need to use the cabs in series using a special cable.

Dave, aka OBBM (kneels down and bows to the God of quality cables), will knock you one up at a very reasonable price.

I used one of these to link two 8ohm cabs to give me 16ohms for my Ampeg - am I still allowed to mention one of these here?- B25.

Catch up with Dave here -


[url="http://www.bassic-bits.co.uk/"]http://www.bassic-bits.co.uk/[/url]


Cheers