[spldrag]

Hi,

I have some doubts when connecting multiple speakers in a one channel one amplifier, and using capacitors as 6th order crossovers on some of the speakers in a series/parallel combination.

Heres the deal, I have the following speakers:
4 - Beyma 8m/nd midrange speakers 4 ohm
4 - Beyma 10mi100 midrange speakers 8 ohm

I know they are diffrent speakers, but for now they are all going to be connected in the same amplifier until I have the money to buy a separate anp.. If needed

The 8m/nd 8" speakers need to be high passed at about 330 hz, so I bought a Solem 120uf  250v capacitor for each.

The 10mi100 speakers are going to be high passed at 125hz with the active crossover that is connected to the amplifier's rca imput.
 
Heres the series/parallel diagram Im thinking of using:



- all 4 8" speakers in series for 16ohm
- two pairs of 10" speakers in series for 16 ohm each pair
- then all parallel for a final impedance of 5.33 ohm

My question is if the cutoff frecuency that each cap gives to each of the 8" speakers would be affected when connecting them all 4 in series?

Would the 10" speakers be affected with the capacitors?

Any other concerns I need to lookout when using this combination?

Thank you

[Speedskater]

Lets skip the second (F & G) and third (H & I) legs for the moment.
In the first leg you have (A+B+C+D) is series for a total of 16 Ohms.
You also have four 120uF caps in series for a total of (120/4) = 30uF.
Is that what you want?

[spldrag]

Thanks for the reply,

Well for 16 ohms and 330 hz the calculator gives me 30 uf, so I assume I have the right capacitor value. Is it better conecting them befor each speaker like in the diagram, or connecting them all in series before the 4 speakers?

[WireNut]

  What do you plan on using for the 120uf Caps 

[Speedskater]

In a series circuit placement order does not matter.  You could just use one 30uF cap and place it anywhere.

[WireNut]

In a series circuit placement order does not matter.  You could just use one 30uF cap and place it anywhere.

 +1

[WireNut]

If you plan on using four 120uf Film caps that can get VERY expensive.
Can't help but wonder what the budget is.

[Speedskater]

I hope that the capacitors are low budget.  With8 speakers on one amplifier channel this will not be a typical stereo setup. 

[spldrag]

Are Solen capacitors acceptable ? I have 4 of these already from a previous proyect, but never fully tested them. They are "Solen PA-MKP-FC 120uf 250v Axial Metallized Polypropylene Film Capatitors"

https://www.solen.ca/pdf/solen/fastcap.pdf

[WireNut]

Are Solen capacitors acceptable ? I have 4 of these already from a previous proyect, but never fully tested them. They are "Solen PA-MKP-FC 120uf 250v Axial Metallized Polypropylene Film Capatitors"

Damn, for me, I wouldn't do it in "My personnel crossover".  I would gang multiply better quality caps.
 

[WireNut]

 There are so many options available. Ganged Sonic Cap Gen 1's or Auricap's would be a good option to consider.

[WireNut]

 Personally I try to avoid crossovers using that large of a value.

[richidoo]

The caps will push the phase of the 8s away from the 10s a little, probably not a big deal except for the fact that is pretty low freq, where phase mismatch is more important. Make sure the 8s and 10s are same net sensitivity or else the 8's filter will upset the FR between 150-330.

Solens are lower on the sound quality totem pole, but since you have them use them. When you want an upgrade, use a better quality single 30uF on the positive side. Or...

The 8" 8mnd's can handle going all the way down to 150Hz, so you don't need the caps to protect them, but maybe you need that for another purpose. Active amplified the driver resonances can be ignored. Since your sensitivity is SO high with 8 drivers on midrange , I doubt you will ever approach the 8mnd excursion limit above 4th order@150Hz, unless these will be spread out over a large distance for PA or something like that.

I bet those high sensitivity Beymas sound very nice...

[WireNut]

 richidoo is in the house.   
 Highly recommended. 

[spldrag]

Thank you all for the replies, Im so glad I found this forum. I have been reading the forum for quite a while and I can definitely learn alot here . Found a new home 

The midrange setup will actually be installed in a competition car combined with Beyma drivers and woofers. The midrange speakers will receive a total of aproximately 1800 watts RMS at 5.33 ohm from a Stetsom digital amplifier , so I really need to be carefull with the low frecuencies.

Which high quality 30-33uf capacitor can handle aproximately 600 watts rms for the 4 8" speakers?