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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => LAB Subwoofer Forum => Topic started by: Dave Garoutte on July 16, 2018, 11:24:29 AM

Title: QSC cardiod
Post by: Dave Garoutte on July 16, 2018, 11:24:29 AM
I just helped a friend with a gig where he used a QSC cardiod sub.
It really did work well!
Just one on one side for a 200ish outdoor gig.
Plenty of kick in front and surprisingly quiet on stage.
Title: Re: QSC cardiod
Post by: John Schalk on July 16, 2018, 01:25:19 PM
I just helped a friend with a gig where he used a QSC cardiod sub.
It really did work well!
Just one on one side for a 200ish outdoor gig.
Plenty of kick in front and surprisingly quiet on stage.

Was it the KS212C?  I heard a demo of one at Sweetwater's Gear Fest and I was impressed by the reduction in rearward bass output.  It seems like a very well thought out sub, but I wondered if the design would have enough output for a typical rock/pop event.  QSC lists 132dB max peak output, but in their measurement note they don't stipulate if that is whole or half space loading.  Interesting that you felt that one per side provided plenty of kick for 200 peeps outdoors.
Title: Re: QSC cardiod
Post by: Dave Garoutte on July 16, 2018, 03:47:40 PM
Yes I believe it was the 12.
This was a beer garden venue.  probably 50' wide x 75' deep.
KW12 tops, single sub, side and front fills.
Not rock concert levels, but plenty loud.
The sub kept up just fine.
Major un-subbage on 15" high stage.
The sub was on stage left.
Title: Re: QSC cardiod
Post by: (Brian) Frost on July 17, 2018, 01:26:15 AM
I really want to know how they compare to a kw181.  since they are more expensive that a kw181 are they even as good when you disregard the benefits of cardiod pattern?
Title: Re: QSC cardiod
Post by: Geert Friedhof on July 17, 2018, 05:40:18 AM
Were the people sitting and quiet? What kind of music? Were the tops crossed or fullrange?
Title: Re: QSC cardiod
Post by: Chris Grimshaw on July 17, 2018, 07:08:37 AM
I really want to know how they compare to a kw181.  since they are more expensive that a kw181 are they even as good when you disregard the benefits of cardiod pattern?

The cardioid sub is a 2x12" design. From what I can tell, they're probably using one of the 12"s to cancel some of the output from the other, so I wouldn't expect it to keep up output-wise with a single 18".

I walked around one a couple of times and the rearward cancellation is pretty impressive. Can't speak much to the sound or output, though - it was only the sub playing at a trade show, so there was background noise and unfamiliar music.

Chris
Title: Re: QSC cardiod
Post by: John Schalk on July 17, 2018, 11:11:03 AM
The cardioid sub is a 2x12" design. From what I can tell, they're probably using one of the 12"s to cancel some of the output from the other, so I wouldn't expect it to keep up output-wise with a single 18".

I walked around one a couple of times and the rearward cancellation is pretty impressive. Can't speak much to the sound or output, though - it was only the sub playing at a trade show, so there was background noise and unfamiliar music.

This was my limited experience with the sub also.  Really good rear rejection (cancellation?) and nice form factor, but uncertain output level.  I would be very surprised if you could do a typical rock/pop act with only one per side and two per side really cuts into the value proposition.  I'd like to see QSC come out with a 15" or even an 18" version of this design.
Title: Re: QSC cardiod
Post by: Art Nadelman on July 17, 2018, 11:17:11 AM
I had the KW181's.  I have the KS212C's.  They have nowhere near the power of the KW's.  But if you're needing a cardioid setup and you don't need a thumping kick drum in your mix, these are fine.
Title: Re: QSC cardiod
Post by: Nathan Riddle on July 17, 2018, 11:49:42 AM
My only question is: Does the KS212C sound better than the KSUB?

I don't care if the rear rejection is so good it removes the air from the room.If it doesn't sound better out front than the KSUB (big flat droning bass) then the design is worthless.
Title: Re: QSC cardiod
Post by: Art Nadelman on July 17, 2018, 02:00:12 PM
My only question is: Does the KS212C sound better than the KSUB?

I don't care if the rear rejection is so good it removes the air from the room.If it doesn't sound better out front than the KSUB (big flat droning bass) then the design is worthless.

That I don't know as I never used the KSub.
Title: Re: QSC cardiod
Post by: Mal Brown on July 18, 2018, 04:42:33 PM
Jeeze I would hope it sounds better than the KSub...  that is no setting the bar very high...
Title: Re: QSC cardiod
Post by: John Schalk on July 19, 2018, 11:56:15 AM
QSC gives 2 x 1800 watt (peak) as the power spec for the KS212C.  That means that this sub is closer to a 2 x 900 watt RMS speaker with 1/2 of that power being used for rear cancellation.  It is a nice package and I can think of a number of scenarios where having its cardioid capabilities would be very useful, but it obviously isn't going to have the same output as the KW181.  Not knocking this design at all, just doing a little thinking out loud so to speak!
Title: Re: QSC cardiod
Post by: Ken Braziel on January 15, 2019, 05:47:52 PM
Ha, that was my sub, hi Dave!

I have two of them, and one of the new single KS112's - sold off my KSUB's & just use these whenever appropriate now. I still have a bunch of KW181's that I use where appropriate. The KS112 has about the same capabilities as the KSUB, I like that it has feet & pole mounts for both tall and side orientations and looks less hokey/more professional.

I've been doing the manually-created cardioid thing with three KW181's for a couple of years now at one of my regular venues, it works great but I really like the convenience of the "cardioid in a box" KS212C's. Next year I'll be using a pair of them in that venue, at least at the start of the season (I'll switch back to the 181's if the cardioid pair doesn't give enough oomph for our more rockin' bands) - hoping that stacking the pair gives enough oomph for the crowd, they don't want it too hot there anyway. It's all live bands so the 44Hz rolloff point shouldn't be an issue.

Guess I should stray beyond the Lounge more often...
Title: Re: QSC cardiod
Post by: Mal Brown on January 18, 2019, 07:31:05 PM
Ha, that was my sub, hi Dave!

I have two of them, and one of the new single KS112's - sold off my KSUB's & just use these whenever appropriate now. I still have a bunch of KW181's that I use where appropriate. The KS112 has about the same capabilities as the KSUB, I like that it has feet & pole mounts for both tall and side orientations and looks less hokey/more professional.

I've been doing the manually-created cardioid thing with three KW181's for a couple of years now at one of my regular venues, it works great but I really like the convenience of the "cardioid in a box" KS212C's. Next year I'll be using a pair of them in that venue, at least at the start of the season (I'll switch back to the 181's if the cardioid pair doesn't give enough oomph for our more rockin' bands) - hoping that stacking the pair gives enough oomph for the crowd, they don't want it too hot there anyway. It's all live bands so the 44Hz rolloff point shouldn't be an issue.

Guess I should stray beyond the Lounge more often...

Ken, when you do cardiod with 181’s... is the setup 3 in a row, center facing back, polarity reversed and 3 to 6 dB lower in volume ?

I have a tent show coming up where I would like to try that setup.  Glad to hear you’ve done it.
Title: Re: QSC cardiod
Post by: Tim McCulloch on January 19, 2019, 11:27:04 PM
Ken, when you do cardiod with 181’s... is the setup 3 in a row, center facing back, polarity reversed and 3 to 6 dB lower in volume ?

I have a tent show coming up where I would like to try that setup.  Glad to hear you’ve done it.

I'm not sure how well a Bessel function would work for cardioid as it's more of a time thing...

With the center reversed, polarity flipped, I'd delay it instead, and keep full power to it.  The desired frequency of greatest cancellation determines the delay time needed.
Title: Re: QSC cardiod
Post by: Ken Braziel on January 22, 2019, 03:52:53 PM
Ken, when you do cardiod with 181’s... is the setup 3 in a row, center facing back, polarity reversed and 3 to 6 dB lower in volume ?

I have a tent show coming up where I would like to try that setup.  Glad to hear you’ve done it.

3 in a row, center reversed w/polarity reversed and a 3.2ms delay, same volume as the front-facing ones. I use a matrix to drive the rear-facing one, the front ones are on an aux (so assign aux only to the matrix, apply delay on the matrix).

This video basically, but I align the subs by lining up the foot-holes which probably explains the difference in the delay: https://www.youtube.com/watch?v=nafin8gE36w