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Chained speakers signal connected in series

I have two pairs of the same model speakers (Tannoy SGM 10B) connected in series to two monoblock amplifiers. The left channel amp drives two speaker cabinets on a left (speakers L1 and L2) and the right channel amp drives two speaker cabinets on a right (speakers R1 and R2).
The positive speaker output of the left amp is connected to a positive post of the first speaker L1(+). Then the negative post of the same first speaker L1(-) is connected to positive post of the second speaker L2(+) with the its negative post L2(-) connected to the amplifier's negative speaker output.

AMP(+) > L1(+)
L1(-) > L2(+)
L2(-) > AMP(-)

Both left channel speakers have a cross-overs build in. Does the audio signal that the first speaker L1 receives from amplifier is any different from a signal the second speaker L2 receives from speaker L1? Does the crossover of the first speaker L1 modify the output signal that goes to a second speaker L2?
esputnix
oldhvymec
5,101 posts
 
I just read your post "DOES NOT change." fiesta75.

Sure it does IN series. The signal path has gone through EVERY component in the first speaker box IF it is a typical series XO. IF it is a parallel OX design (like a Quasi second order) and BI AMPABLE it would STILL pass through all the XO filters BACKWARDS (?) in the bass or the mid/highs XOs after it went through every component in the first speaker box..  + - + -, is every component including the speaker terminals and VCs.

It’s IN SERIES, not Series/parallel or Parallel/series BUT one AFTER the OTHER.

How you like that for Techno talk.. I use to have to teach smart apprentices. Oh yea, they were smart alright. .Just like I use to be.. :-)

How’s my math by the way, you notice, no numbers applied for the unsighted.. I’m close after 50+ years of welding.. I strike an arc I can see just fine. TIG, MIG, TWIG, TWIT, TWILL, TWASEN’T.. LOL

Regards
fiesta75
1,378 posts
 
I will post some sketches tomorrow. If you connect the second speaker just across the woofer of the first speaker, the second speaker will see both inductors. I'll show you what I mean, but if you care to just plug some numbers into the "grade school" math equations, you will be able to see without me having to post anything... Elementary school?🤣
imhififan's avatar
imhififan
2,212 posts
 
@fiesta75, 
Can we agree that Rt equals 16ohms in series?
Yes
Can we agree that Lt = L1 + L2 in series?
No, IMO, the first woofer will see the voice coil of second woofer as an inductor in series, same for the second woofer, it will see the voice coil of first woofer as an inductor.
I think the total inductance should be Lt = L1 + L2 + Lvc1 + Lvc2
Can we agree that 1/Ct = 1/C1 + 1/C2 in series?
Yes
it's yes to the above, then simply plug those numbers into the equations. f = R/2πLQ and f = Q/2πRC. 
May be a crossover design simulator software can give us a better answer.

fiesta75
1,378 posts
 
Even if L1 and Lvc1 are present, L2 and Lvc2 are also present. If the frequency of the crossover is say 2kHz., it will remain at 2kHz., because L1+Lvc1 equals L2+Lvc2. Is that not correct? L1 = L2 and Lvc1 = Lvc2 for each speaker. Both inductances are present whether they are used to calculate the crossover frequency or not. Correct?
Perhaps a crossover design simulator would give us a better answer, I am willing to listen to your presentation. That could save me the hassle of posting sketches. I think we are both capable since we have been working to solve the problem with likklegerry's crossovers. I will be waiting.
rodman99999
6,185 posts
 
 While you're listening through your pencils: you're going to simply ignore everything that a voice will induce to a signal, when actually presented with music?

                                        HILARIOUS (in a tragicomedic way)!

     Best broaden your horizons, as to what goes on (and can be measured/calculated) when certain elements (ie: caps and voice coils) are actually under the influence of *changing frequencies (ie: an actual audio signal) as opposed to DC (ie: a multimeter).

     *Ever looked at the impedance plot of a woofer, actually being used in a circuit?

       (https://audiojudgement.com/speaker-impedance-curve-explained/)    

           (https://www.apogeeweb.net/tools/reactance-calculator.html)

       Perhaps: even plug some of those facts, into your calculations?

  (http://oer2go.org/mods/en-boundless/www.boundless.com/definition/reactance/index.html)                
 
                       NAH, why bother with Physics, right? 🙄

          ps: I only bother posting such things, knowing they will be ignored by most, BUT: hoping someone out there remains interested in facts/learning.

                                             Happy LISTENING!
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