Q's regarding the Marshall Dynamic Bass System 7400

[JensWest]

Hi all!

In the back of it, it says:

"Minimum load 2 Ohm
(400 W R.M.S.)".

There are two outputs and they each need a minimum load of 4 Ohm.

Now, how much effect do I get if I connect it to two cabs á 4 Ohm and how much do it get if I connect one 4 Ohm cab?

Thank you!

Edited February 18, 2014 by JensWest

[Musky]

If both cabs are the same then using two 4 ohms cabs will be about 5dB louder - 3dB from the extra speaker and about 2dB from a typical 50% increase in power by running at half the impedance.

Edit: You'll get an improved LF output as well.

Edited February 19, 2014 by Musky

[dudewheresmybass]

I'm currently running my 7400 as detailed by musky.
The low end is huge from this rig. ( I'm using a pair of mbc410 cabs)

[JensWest]

[quote name='Musky' timestamp='1392768956' post='2372650']
If both cabs are the same then using two 4 ohms cabs will be about 5dB louder - 3dB from the extra speaker and about 2dB from a typical 50% increase in power by running at half the impedance.

Edit: You'll get an improved LF output as well.
[/quote]

Thank you for your answer, Musky!

But, will the amp deliver 400 W at 4 or 2 Ohm?

[Musky]

[quote name='JensWest' timestamp='1392778381' post='2372682']
Thank you for your answer, Musky!

But, will the amp deliver 400 W at 4 or 2 Ohm?
[/quote]
It'll be 400w at 2 ohms and approximately 270w at 4 ohms.

[JensWest]

OK, great.
Thank you!

[Guest bassman7755]

The marshall DB series (at least my old 7200 was) are 4ohm minimum total load AFAIK so you cannot connect 2 4ohm speakers at the same time.

[JensWest]

[quote name='bassman7755' timestamp='1392820958' post='2373089']
The marshall DB series (at least my old 7200 was) are 4ohm minimum total load AFAIK so you cannot connect 2 4ohm speakers at the same time.
[/quote]

Even if the manual says you can...?

[url="http://www.docstoc.com/docs/20390605/Dynamic-Bass-System---DBS-7400"]http://www.docstoc.c...stem---DBS-7400[/url]

It sais so in the back of the head too, as stated in the first post.

Edited February 19, 2014 by JensWest

[Guest bassman7755]

[quote name='JensWest' timestamp='1392821074' post='2373092']
Even if the manual says you can...?

[url="http://www.docstoc.com/docs/20390605/Dynamic-Bass-System---DBS-7400"]http://www.docstoc.c...stem---DBS-7400[/url]

It sais so in the back of the head too, as stated in the first post.
[/quote]

Fair enough, I falsely assumed the only difference between them as power output.

[Lozz196]

Having had a DBS7400 - connected to a 4ohm Marshall VBC412 - there really isn`t a need for two 4ohm cabs. These amps are incredibly loud, and have a really great full sound. I don`t think I ever had it on more than 3 on volume, and that was on an outdoor gig with no FOH PA, only vox through it.

[dudewheresmybass]

The 7200 will only run at a min of 4 ohms, where the 7400 does 2 ohms.
It's the main reason I moved from my 7200 to the 7400.