Help required connecting 2 Bass heads together

[luked]

Apologies if this subject has been covered before i'm new to this forum.I've recently purchased a Gallien Krueger MB800 head,live i usually use two 4 ohm bass cabs,as this amp doesn't go down to 2 ohms i was wondering if i could somehow hook up my Gallien Krueger to another bass head(or power amp) to power the second cab.I've read an ab y pedal or tuner pedal could split the signal into 2 amps heads,just wondering if there is any other way.Photo of back panel of GK attached.Any help much appreciated.

[0175westwood29]

you could use one of these and put your cabs in series to give a load you amp can use? that way no need for another amp at all

 

https://www.gear4music.com/Guitar-and-Bass/Palmer-CAB-M-Passive-Cabinet-Merger/T2K?origin=product-ads&gclid=CjwKCAjwo7iiBhAEEiwAsIxQEaqwCOl2ApiEFmzClqNBym5idubTrMOpL4rzpszYkyD-6enOf8-H8BoCNqwQAvD_BwE

Edited April 30, 2023 by 0175westwood29

[Bill Fitzmaurice]

Send the line level out to a power amp, or the effects return of another integrated amp.

[luked]

cheers for the help,the palmer box looks ideal,never new anythng like that was available,i've got a gig tonight so i'll try the line out option for tonight.thanks again

 

[BassmanPaul]

I use 4Ω Acme B2 2x10 cabinets and I run them one per channel of a class D power amp. It works well.

[BassmanPaul]

On 30/04/2023 at 11:48, luked said:

cheers for the help,the palmer box looks ideal,never new anythng like that was available,i've got a gig tonight so i'll try the line out option for tonight.thanks again

 

As for this Palmer box I wouldn't use it.  It only has 1/4" phone sockets that are not safe to use with a high power solid state amp.  SpeakOns are the only way to go for this service. All you need is a plastic box and three NL4 SpeakOn sockets. If you want to build such a box I'll tell you how to wire it.

[chris_b]

On 30/04/2023 at 15:26, luked said:

I've recently purchased a Gallien Krueger MB800 head,live i usually use two 4 ohm bass cabs,as this amp doesn't go down to 2 ohms i was wondering if i could somehow hook up my Gallien Krueger to another bass head(or power amp) to power the second cab.I've read an ab y pedal or tuner pedal could split the signal into 2 amps heads,just wondering if there is any other way.Photo of back panel of GK attached.Any help much appreciated.

 

 

Connect an amp into each cab and run an instrument cable from the Send on one to the Return of the other. Job done.

 

The preamp on the first (Send) amp will drive the power sections in both amps. Only the Master will work on the second (Return) amp.

[BassmanPaul]

An other thing about using a Series box is that you will not get all the power out of the amp that it's capable of. The amp will see 8Ω and thus will give less than it's 4Ω level of 800W.

 

When buying an amplifier to use with your existing speaker cabinets it's wise to consider their impedances and verify that the amplifier is capable of driving them safely. 

Edited May 14, 2023 by BassmanPaul

[itu]

4 hours ago, BassmanPaul said:

An other thing about using a Series box is that you will not get all the power out of the amp that it's capable of.

 

When buying an amplifier to use with your existing speaker cabinets it's wise to consider their impedances and verify that the amplifier is capable of driving them safely. 

The first sentence should point out that the difference in dBs is minimal. So many watts, so little decibels.

 

The second comment is feasible. Usually if your main cab is 8 ohms or more, another cab is a potential possibility for more loudness.

[Downunderwonder]

On 01/05/2023 at 03:33, Bill Fitzmaurice said:

Send the line level out to a power amp, or the effects return of another integrated amp.

 

11 hours ago, chris_b said:

 

Connect an amp into each cab and run an instrument cable from the Send on one to the Return of the other. Job done.

 

The preamp on the first (Send) amp will drive the power sections in both amps. Only the Master will work on the second (Return) amp.

There's an echo in here. Job done. No need for any more gear.

[BassmanPaul]

20 hours ago, itu said:

The first sentence should point out that the difference in dBs is minimal. So many watts, so little decibels.

 

The second comment is feasible. Usually if your main cab is 8 ohms or more, another cab is a potential possibility for more loudness.

Not wanting to argue with you but if your main cab is 8Ω and you try to add a second cab that is 4Ω to a 4Ω minimum amplifier what is going to happen?

I was trying to pass on information to someone who may not understand impedances. I wanted to keep matters simple.

 

[BigRedX]

@BassmanPaul

 

For cabs in parallel (which is what you get when you connect two cabs to an amp) the formula is:

 

1/R1 + 1/R2 = 1/R3

 

So for an 8Ω and a 4Ω cab together it is 1/8 + 1/4 = 3/8 = 2.67Ω which is too low an impedance for your 4Ω minimum amp and it will either go into protect mode or go pop depending on how ell it was made.

Edited May 16, 2023 by BigRedX
So as not to upset @Downunderwonder

[Downunderwonder]

Jeebus. OP has two amps and two 4 ohm cabs. The solution is trivial and has been given three times. Only requires a spare 1/4 patch lead to link the amps fx send of the bass input amp to fx return of the slave amp. Now that's four times. Give it a blimin bone!

[BassmanPaul]

9 hours ago, BigRedX said:

@BassmanPaul

 

For cabs in parallel (which is what you get when you connect two cabs to an amp) the formula is:

 

1/R1 + 1/R2 = 1/R3

 

So for an 8Ω and a 4Ω cab together it is 1/8 + 1/4 = 3/8 = 2.67Ω which is too low an impedance for your 4Ω minimum amp and it will either go into protect mode or go pop depending on how ell it was made.

 

I know but to be accurate the formula is  1/RTotal =.1/R1 + 1/R2 LOL