can i put an equalizer between Powered mixer outs and speakers?

earworm

New member
ok, i'm going to help a band with their live performances,
they got all their cheap gear and want me to make them better

so they got this "sound bank sound" powered mixer,
doesn't sound good at all but hell, it works,
its got two main outputs of
250W @ 4 ohm (on each channel) , both are only Speakon outs,

1) i'd like to put a limiter or EQ between the main outs and speakers,
but isn't it dangerous to connect an EQ to a 4 ohm output?
can it harm the equipment?

and how would i do that, take a short "speakon-to-jack"cable from the mixer to the eq,
and then connect the eq out to the speakers,
i'll just find me some short speakon-to-jack cables if this won't harm any "line level equipment"

and next; i can't find info or a manual of that mixer, since its infamous junk,
it doesn't have a master insert which is too bad, but it does seem to have
2) MASTER AUX stereo send and return, seems like this is seperate from the AUX1 and AUX2 (send+return)

why would you wanna put a reverb or something on your main mix,
might this just be a master INSERT instead of master LOOP (like its called)

bad news is that i can't test anything, got a live PA on saturday and then i'll have to see that i can handle this stuff or not, its easy to use but it doesn't sound good, so its gonna take some time and effort to "fix it"

thanks in advance for any advice



3) additional question; is speakon Balanced?
i got some NL2fc cables here...

4) so we got two Montarbo speakers,
http://www.montarbo.it/pdf/W400P_manual.pdf (this is the new version of the speakers)
speakon connection to the powered mixer, but these two montarbo's have "PARALLEL INPUTS",
the band has on one of those parallel inputs another speaker connected, in serie,
so now they have 2 Montarbo's for FOH,
and two 'bird electronics' speakers for monitoring, and these birds are connected "via parallel inputs" to the Montarbo's,

now whats up with the OHM stuff.... if i'm correct the montarbo's are 8 ohm, the mixer outs are 4 ohm, .... and i don't know how much the Birds speakers aer... are we loosing signal here because of impedance issues?

4ohm mixer out to 8 ohm speaker in (is this OK??)
and then those 8-ohm-speakers have to split the signal with two other speakers, are those extra speakers supposed to be 4 ohm then?

something doesn't sound logical to me..;what do you think?
 
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earworm said:
1) i'd like to put a limiter or EQ between the main outs and speakers,
but isn't it dangerous to connect an EQ to a 4 ohm output?
can it harm the equipment??

It's not the impedance, it's the fact that speaker outputs are power ouputs, not just signal outputs. Hooking up an EQ or limiter to speaker jacks will fry it. Don't do it.


earworm said:
it does seem to have
2) MASTER AUX stereo send and return, seems like this is seperate from the AUX1 and AUX2 (send+return)

why would you wanna put a reverb or something on your main mix,
might this just be a master INSERT instead of master LOOP (like its called)...?
This might be the place to put your EQ/limiter. An insert is just a loop. It has an out and an in, just like a loop. The question will be is this a loop that only affects the aux sends, or does it patch into the main mix? If it interrupts the main outs, you are golden. Patch in your EQ/limiter there


earworm said:
3) additional question; is speakon Balanced?
i got some NL2fc cables here...?

No, speaker cables are not balanced.


earworm said:
4) so we got two Montarbo speakers,
http://www.montarbo.it/pdf/W400P_manual.pdf (this is the new version of the speakers)
speakon connection to the powered mixer, but these two montarbo's have "PARALLEL INPUTS",
the band has on one of those parallel inputs another speaker connected, in serie,
so now they have 2 Montarbo's for FOH,
and two 'bird electronics' speakers for monitoring, and these birds are connected "via parallel inputs" to the Montarbo's,

now whats up with the OHM stuff.... if i'm correct the montarbo's are 8 ohm, the mixer outs are 4 ohm, .... and i don't know how much the Birds speakers aer... are we loosing signal here because of impedance issues?

4ohm mixer out to 8 ohm speaker in (is this OK??)
and then those 8-ohm-speakers have to split the signal with two other speakers, are those extra speakers supposed to be 4 ohm then?

something doesn't sound logical to me..;what do you think?

Parallel inputs on a speaker do exactly that- when you plug another speaker to the parallel input, they are in parallel, not series.

The mixer can do 4ohm loads. Two 8ohm speakers paralled is 4ohms. So the side with the two Montarbos is fine.

The birds, I don't know. If they are 8ohms, and paralled, you will be fine. Just don't parallel them if they are 4ohms, as the load will be too low for the amp.
 
amazing clear reply! i appreciate that !!

one more thing, ok, so speaker outputs can hurt eq's and stuff,
what about running speaker outputs trough a snake,
that won't hurt the snake, right? (as long is i just connect the speakers on the other end of the snake),
speaker output doesn't care about the cable it goes trough,
but it does matter what is connected on the other side of the cable,
thats the point right?

thanks for the info already,
cheers,
earworm
 
The only problem running speaker level through a snake is the wire isn't big enough to handle the current.

That's the big difference between line signals and power- power signals have lots of current, which needs a big cable to flow through.

It's like a garden hose against a fire hose. They both may shoot fifty feet (have the same voltage) but the fire hose can move a lot more water (higher current). Trying to force more water through the garden hose may damage it.

Unless the snake has a set of speaker lines in it, run seperate speaker lines for the speakers.

:) Have fun!
 
1) No:... Do not connect an equalizer between the powered speaker-outs on the mixer and the speakers! You'll fry the inputs on your equalizer, in a hurry!

2) Master Aux Send/Return,... by the wording in your post, this sounds normal and/or typical. Not 100% sure in this case, but this may either be a separate section, OR the "Master" level control pots for both Aux-Send and Aux-Return. Again,... normal. For reverbs and similar effects, you'd preferrably have it in an "effects loop" on Aux-Send/Aux-Rtn circuits. It's compressors that you'd typically want inline, on Inserts.

3) No:... The Speakon connection is NOT balanced.

4) If I read your description correctly,... then the way the speakers are connected is totally correct.

For each channel: (L/R), the mixer-to-Speakon connection represents 8-ohms load. Plugged to that, in PARALLEL is the "Bird" speaker, which assuming it's also 8-ohms,... would represent a total load of 4-ohms per channel.

Resistance in SERIES is additive, increasing resistance by adding the two loads,... which is NOT the case with these "PARALLEL INPUTS" on the Montarboes. So,... your okay on that.

Resistance in PARALLEL is a "division"-type of resistance load,... where 8-ohms in parallel with another 8-ohm load has a 4-ohm total load. There's math involved,... that's the reciprocal of the sum of all the resistances.

It's a bit hard to explain, so pls reference the formula below, also this site:

http://www.physics.uoguelph.ca/tutorials/ohm/Q.ohm.intro.parallel.html
 

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A Reel Person said:
1) No:... Do not connect an equalizer between the powered speaker-outs on the mixer and the speakers! You'll fry the inputs on your equalizer, in a hurry!
http://www.physics.uoguelph.ca/tutorials/ohm/Q.ohm.intro.parallel.html

I just seen last night somebody who think that he knows a lot, fried his expensive EQ set: doing just that. Before this he had a mixer and power amp and have his EQ between the mixer and power amp. Sold off the mixer and his amp and got a powered mixer but put his EQ at the wrong spot. This is in a karaoke club
 
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