2 x 210 vs 1 x 410 at 8 Oms

[Undertone]

Hi,

Does anyone know of some sort of box on the market that causes speaker cab impedance to add in series rather than (what I believe is) the usual parallel combining please?  I don't want to tinker with the wiring inside any of the cabs.

I use a 410 & 115 cab (8 ohms each, for a 4 Ohm total (in parallel)) and want to replace the 410 with 2 x 210 (8 ohm each). I'm restricted to 8 Ohms each as these are all Hartke. This can't be done (I think) to give total 4 ohms, but if I can 'series' the 2 x 210's to give 16 Ohm, then 'parallel' that with the 115, it gives 5.333 Ohms total, which is probably good enough (and each speaker will handle its resulting power allocation (amp is 400W into 4 Ohms)).

Do (please!) point out any flaws in my calcs.  Any other practical suggestions (using the cited cabs) welcome.

Regards

 

[Merton]

https://www.andertons.co.uk/guitar-dept/electric-guitar-accessories/other-electric-guitar-accessories/palmer-cab-m-passive-cabinet-merger

Doesn't give a max power rating though, so be wary of that!

[jrixn1]

1 hour ago, Undertone said:

I use a 410 & 115 cab (8 ohms each, for a 4 Ohm total (in parallel)) and want to replace the 410 with 2 x 210 (8 ohm each). I'm restricted to 8 Ohms each as these are all Hartke. This can't be done (I think) to give total 4 ohms, but if I can 'series' the 2 x 210's to give 16 Ohm, then 'parallel' that with the 115, it gives 5.333 Ohms total, which is probably good enough (and each speaker will handle its resulting power allocation (amp is 400W into 4 Ohms)).

It's not the most efficient setup, as 2/3 of the power will go to the 1x15, and just 1/6 to each of the 2x10s.

https://www.speakerimpedance.co.uk/?act=three_series_parallel2&page=calculator

Are two 2x10 powered by 63W each going to be much louder than one 2x10 powered by 200W?  If not, you might as well just leave the second 2x10 at home.

What is the problem with the 4x10?  E.g. not loud enough, too heavy, ...?

[TomasFlats]

This is quite useful...

https://geoffthegreygeek.com/multiple-speakers-share-power/?amp
 

[Phil Starr]

It's simple enough to wire up a special lead to combine your cabs the way you want and @Chienmortbb would do that for you.

It doesn't make sense though. So much of the power will go through the 15 that it's sound will dominate and the 10's will be almost. Using a single 8 ohm 2x10 would match the 1x15 much better, and probably better than an 8ohm 4x10 depending upon what sort of a sound you want.

another option might be to swap around the drivers from the 4x10 for the ones in the 2x10's but honestly I don't see the point unless there is a particular sound you are trying to achieve. If you are keeping all four cabs you already have loads of options. The mis matching 3 cab solution makes little sense

[Undertone]

Thanks for the replies & links people.  Particularly also for that concerning efficiency. I'd calc'ed that the cabs can handle the power allocation but overlooked that most of it goes to the 115.

Main issue is weight, despite HyDrive HX's being neo, I'm mid 40's with a small back issue and don't want to exacerbate it. The 410 is only 4kg heavier than the 115 but I'd rather not carry 2 such weights. Prefer the 115 and 2 lots of 14kg (separately). Flexibility also useful as I could take a 115 + 1 x 210 to smaller gigs (like there's lots of those at the moment....).

I thought it might not be possible / useful.   Regards again.