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Title: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Patrick Elias on September 29, 2015, 01:27:47 am
Hi all,

I'm by no means a sound expert but would greatly appreciate some assistance with achieving the best possible sound from my set-up. I own 2x RCF 422s tops and 2x RCF 4pro8003as subwoofers. I'm confused as to which setup will produce the best possible sound and ensure the longevity of the speakers/subs.

How I currently set up the sound
From my mixer (assume left channel), I connect directly to the left output of the sub (#6 on attached picture). From there, I connect another XLR from the left input of the sub (#1) to the output on my top speaker. I repeat this same process for the right channel. I then finally push the Link/Xover OUT switch (#8) and leave the Xover switch (3) untouched at 80hz

How another experienced user is recommending I set up the sound
Go from my mixer to the top speaker and then connect in to the RCF sub without pushing any of the crossover buttons. Apparently this will bypass the limiter on the sub?

Can anyone please shed some light and point me in the right direction? Any advice will be much appreciated.

Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Scott Holtzman on September 29, 2015, 02:02:41 am
Before anyone can help you need to change your display name to your real name.  once you comply with the forum rules we can help.

Sent from my SM-T800 using Tapatalk

Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Patrick Elias on September 29, 2015, 02:34:52 am
Before anyone can help you need to change your display name to your real name.  once you comply with the forum rules we can help.

Sent from my SM-T800 using Tapatalk

Missed that one in the set up process - real name has been updated!
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Keith Broughton on September 29, 2015, 07:23:10 am
Into the sub, press the crossover switch (#8 in the pic)and set crossover to 80 (switch 9)
Connect ouput of sub to top box.
You can try the 80 or 120 position to hear which sounds better.
As far as I know, there is no switch to disable the limiter in the sub.

 
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: frank kayser on September 29, 2015, 12:31:01 pm
Hi all,

I'm by no means a sound expert but would greatly appreciate some assistance with achieving the best possible sound from my set-up. I own 2x RCF 422s tops and 2x RCF 4pro8003as subwoofers. I'm confused as to which setup will produce the best possible sound and ensure the longevity of the speakers/subs.

How I currently set up the sound
From my mixer (assume left channel), I connect directly to the left output of the sub (#6 on attached picture). From there, I connect another XLR from the left input of the sub (#1) to the output on my top speaker. I repeat this same process for the right channel. I then finally push the Link/Xover OUT switch (#8) and leave the Xover switch (3) untouched at 80hz

How another experienced user is recommending I set up the sound
Go from my mixer to the top speaker and then connect in to the RCF sub without pushing any of the crossover buttons. Apparently this will bypass the limiter on the sub?

Can anyone please shed some light and point me in the right direction? Any advice will be much appreciated.
I'm not sure how the jacks are connected - either paralleled of via some internal circuitry. But...

Mixer to Sub OUT? Sun IN to top OUT?

Wouldn't a normal cabling scheme be Mixer to SUB IN and then Sub OUT to TOP IN?
or
Mixer to TOP IN and then TOP OUT to SUB IN?
frank
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Patrick Elias on October 09, 2015, 11:22:42 am
Into the sub, press the crossover switch (#8 in the pic)and set crossover to 80 (switch 9)
Connect ouput of sub to top box.
You can try the 80 or 120 position to hear which sounds better.
As far as I know, there is no switch to disable the limiter in the sub.
Thanks Keith. Yeah this is how I've been setting it up and while it sounds great, the orange limiter light flashes quite a bit when the subs are not even at half way (12 o clock). I'm not sure if this is damaging the sub-woofer or will wear it out?

Do you know of anyone who sets their sound up from mixer to top (input) and from top (output) to Sub (input)?
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Patrick Elias on October 09, 2015, 11:25:38 am
I'm not sure how the jacks are connected - either paralleled of via some internal circuitry. But...

Mixer to Sub OUT? Sun IN to top OUT?

Wouldn't a normal cabling scheme be Mixer to SUB IN and then Sub OUT to TOP IN?
or
Mixer to TOP IN and then TOP OUT to SUB IN?
frank
Hi Frank, thanks for your comment. Yeah im trying to clarify the best cabling system and see whether it's recommended to go from mixer to top or mixer to sub first. How do you set your speakers up?
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Jonathan Kok on October 09, 2015, 04:53:24 pm
Thanks Keith. Yeah this is how I've been setting it up and while it sounds great, the orange limiter light flashes quite a bit when the subs are not even at half way (12 o clock). I'm not sure if this is damaging the sub-woofer or will wear it out?

Do you know of anyone who sets their sound up from mixer to top (input) and from top (output) to Sub (input)?
I'm afraid he gave you the one and only correct answer that will provide you with the best possible sound while properly protecting your speakers. What the other 'experienced tech' told you was BS; you cannot bypass the limiting of the subwoofer (or the tops, for that matter). It's there for your financial protection. Running it from the mixer to the tops to the subs will provide you with exactly the same results as running it from the mixer to the subs to the tops without the crossover engaged (as you indicated you normally run it).
If you're having issues with the subwoofer's limiting, it is because you are sending it too much signal, and relying on too little subwoofer to provide the low end you're looking for. Solution? Add more subwoofers.
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Patrick Elias on October 12, 2015, 11:01:56 pm
I'm afraid he gave you the one and only correct answer that will provide you with the best possible sound while properly protecting your speakers. What the other 'experienced tech' told you was BS; you cannot bypass the limiting of the subwoofer (or the tops, for that matter). It's there for your financial protection. Running it from the mixer to the tops to the subs will provide you with exactly the same results as running it from the mixer to the subs to the tops without the crossover engaged (as you indicated you normally run it).
If you're having issues with the subwoofer's limiting, it is because you are sending it too much signal, and relying on too little subwoofer to provide the low end you're looking for. Solution? Add more subwoofers.

Thanks for your input Jonathan! I'm with you and logic would support the setup from mixer to subs and then to tops with crossover engaged. If i'm not mistaken, if the crossover is not engaged then the low frequencies will not be isolated to the sub below 120/80 hz.

When set up correct, the only thing i dont understand is why the limiter still flashes orange when the subs are turned to say even 11 o clock (clean signals sent from mixer - no red-lining). I'm running two 18" subs 1000w each and two 12" tops 400w each so I would have thought that's more than enough sub power to run the tops?
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Jano Svitok on October 23, 2015, 10:18:18 am
i dont understand is why the limiter still flashes orange when the subs are turned to say even 11 o clock.

What does an amplifier in fact do is to multiply the voltage by some coefficient (the coefficient is usually something around 32 dB ~ 39x, but depends on the model). I'm not sure, but I suppose the volume control affects the amp coefficient, so output voltage = input voltage * amp coefficient.

Voltage / impedance of the speakers = current to speakers. Power to speakers = voltage * current = voltage^2 / impedance = input voltage^2 * amp coefficient^2 * impedance.

That means output power is dependent on 1) input voltage = output from mixer 2) volume setting 3) speaker impedance, which is fixed so we can leave 3 off.
It is  clear that even with lower volume setting, it is possible to achieve full output when high enough input is fed to amp from mixer.

I assume from spec sheet that with volume at 12 o'clock the input for full power is +4dBu = 1.22 V and at the very right position -2 dBu (0,6 V). Now check your mixer's specs what it's output level is.

You may try to run sine wave through your mix to the subs and check at what level the subs start limiting and if it correlates with the above or not.

Also, you may try to setup

Obviously, there might be a problem with the box, but if both behave similarly the probability is pretty low.

I'm running two 18" subs 1000w each and two 12" tops 400w each so I would have thought that's more than enough sub power to run the tops?

This depends on the style/music, in other words on desired lows:highs ratio and overall volume. Low frequencies are pretty sensitive to room configuration (reflections etc.) so they may disappear at some places and reappear again in a few meters.
Title: Re: Best setting for connecting RCF speakers to RCF subwoofers
Post by: Jano Svitok on October 23, 2015, 10:19:06 am
What does an amplifier in fact do is to multiply the voltage by some coefficient (the coefficient is usually something around 32 dB ~ 39x, but depends on the model). I'm not sure, but I suppose the volume control affects the amp coefficient, so output voltage = input voltage * amp coefficient.

Voltage / impedance of the speakers = current to speakers. Power to speakers = voltage * current = voltage^2 / impedance = input voltage^2 * amp coefficient^2 * impedance.

That means output power is dependent on 1) input voltage = output from mixer 2) volume setting 3) speaker impedance, which is fixed so we can leave 3 off.
It is  clear that even with lower volume setting, it is possible to achieve full output when high enough input is fed to amp from mixer.

I assume from spec sheet that with volume at 12 o'clock the input for full power is +4dBu = 1.22 V and at the very right position -2 dBu (0,6 V). Now check your mixer's specs what it's output level is.

You may try to run sine wave through your mix to the subs and check at what level the subs start limiting and if it correlates with the above or not.

Obviously, there might be a problem with the box, but if both behave similarly the probability is pretty low.

This depends on the style/music, in other words on desired lows:highs ratio and overall volume. Low frequencies are pretty sensitive to room configuration (reflections etc.) so they may disappear at some places and reappear again in a few meters.