Power Mixer-> Power Sub

Without knowing what you are using for a PA no one can help you.

 

I you have a preamp or mixer send and a power amp return, then you can out a crossover th e loop. Bring the highs back to the mixer, send the lows to the sub.

If you tops are powered, you may be able to send them the signla direct from the subas many have hi pass filters built onto the signal pass through.

We'll need to know which mixer and which sub and which top boxes to really help...

 

A sub will typically be crossed over in the neighborhood of 100 Hz. Although that helps take some of the load off the tops, they're still left carrying a fair bit of bass and kick. Whether they're up to the challenge depends on their design and the SPL you'll want from them.

 

Do you have model numbers for the board and cabs? That'd help us help you.

You should be able to take a line level out from the board to feed a powered sub, or else you may be able to use an aux send. Some of the older Yamaha powered mixers have a high pass switch for the mains, which would also help keep the lows out of your mains, and leave them for your sub to handle. That way the sub does the heavy lifting instead of your smaller mains.

With smaller main cabs, your can set your sub's cross a bit higher to cover. A sub will make a huge difference in the perceived power of your system.

 

MM6
Specifications
Number of Channels 6
Mono Channel EQ Low, High
Stereo Channel EQ N/A
Channel Effects All Channels
Monitors Effects No
Inputs - XLR (bal) Ch. 1 - 6
Inputs - 1/4 IN Ch. 1 - 4
Inputs - RCA (unbal) 2 Pairs
Clip / Mute LED Master Section
Phantom Power NA
Internal Effects Spring Reverb
Effects Send Yes
Effects Return Yes
Effects Return to Main Yes
Effects Return to Monitor No
Reverb / Effects Footswitch Yes
Record Outputs 1 Mono RCA Pair
Max Gain to Line Out -Mic Input (dB) 55
Max Gain to Line Out -Line Input (dB) 40
Master EQ -1 (type/Channels/Range -dB) Graphic / Mono / 6 Band 63 Hz - 16,000 Hz
Main Outputs (Line Level) 1x 1/4 inch (TRS). --- send this to crossover
Main Amp Inputs (Line Level) 1x 1/4 inch (TRS) --- return highs back to the power amp here
Outputs - Amp A - 1/4 IN Jacks 2
Mixer - Signal to Noise Ratio (dB) 90
Mixer - Freq Resp (Tone and EQ Flat,±2dB) 20 Hz - 20,000 Hz
Mixer- Input Ref Noise to line out @150 Ohms(dBv) -117
Mixer THD (Main out w/ -10dB input) less than 0.05%
Amp A-Power [email protected] Ohms (0.1 PER THD 1kHz) 85
Amp A - Power Output @ 4 Ohms 150
Amp C-Power [email protected] Ohms (0.1 PER THD 1kHz) 0
Amp C - Power Output @ 4 Ohms 0
Amp D-Power [email protected] Ohms (0.1 PER THD 1kHz) 0
Amp D - Power Output @ 4 Ohms 0
THD - 1kHz (dB) less than 0.05%
THD - 20Hz-20kHz (dB) less than 0.1%
Hum and Noise (un / Aweight -dB) -96
Typical crosstalk -1 kHz (dB- less than -60
Input Impedance - Bal/Unbal (Ohms) 2200/10K
Input Sesitivity (Vrms Sine) 1.4 V
CMRR @ 60Hz (min/typ) 54 dB / 66 dB
Max Votage Gain (dB) 25
Power Consumption (typ/max) 110 VA / 320 VA
Protection Thermal / Load / DC
Cooling Passive Heat Sink
Transformer Type El Core
Finish Blue/Black Carpet, Scratch Resistant Front Panel
Chassis Construction Heavey Gauge Metal with Plywood Cabinet
Dimensions (DWH, inches) 10 x 21 x 9.25
Dimensions (DWH, cm) 25 x 53 x 24
Weight (lbs/kg) 31 / 14
Specifications subject to change without notice


Main line out to an electronic crossover DbX123 or equivalent. Lows to the sub and highs returned to the main line In.

Think of it as an effects loop. There is your best bet. Crossover should run ya $75 to $100 used.

 

Well I think you could maybe come out of the main out jack into a powered subwoofer and from there you would come back into the mixers amp in from the subwoofer high pass out. Not every powered subwoofer will work. Personally if it was me I would just upgrade your current set-up.

 

I think you should just buy whatever crap off Craigslist you can afford and start cabling it together until something works.



p.s. Don't do this ^

 

Agreed on the upgrade but to do it on the cheap the approach outlined above will work. The powered subs I have worked with from QSC, JBL and Yamaha were lpf only on the sub and full range on the pass thru.

i would use the external x-over as it isn't a bunch of extra cash.

 

I'm curious as well. I'm planning to add a sub to my powered mixer system but mine has a dedicated sub out (already crossed over). All powered mixers should have this feature in my opinion. I'm curious about the returing a signal to the mixer from the crossover unit and how that works.

 

You can also just invest in a better pair of speakers. Bump up to a pair of 15's rated at 400W and you'll never have to worry about your amp putting out enough power to blow the speakers. Plus, your vocals will sound better for your gigs.

I run Carvin's 15" pa speakers, rated as above, with a small Carvin PA and have never worried about bass blowing out the speakers.

I have worried about blowing out my back lifting them up and placing them on the stands, though. They weigh a bunch.

Rock on,
'Bolt

 

Yes - that is what 4Mal is saying to do. If you don't mind getting the external crossover this is the best plan.

Personally - I just added a sub to my Behringer powered mixer for a gig a couple of weeks ago. I didn't bother with the external crossover (although I do have one) - I just ran the main out into a bridged Crown XLS2000 amp with the low pass filter set to 105 hz and then to a Carvin LS1801 sub cab. Now with this setup the top speakers are still operating full range (so they are getting the low freqs too), but from what I found the addition of the sub allows you to run the gain lower since you don't have to crank everything to get the bass out of it - so my top speakers (Carvin PM12) were having no issues with too much low end.

What I did is identical to if you just ran a main out from your powered mixer to a powered sub with a 100 hz LPF.

 

Sig worthy and often times tragically true.

Riis