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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 => SR Forum Archives => LAB Subwoofer FUD Forum Archive => Topic started by: Steve Shafer on June 02, 2004, 09:51:35 PM

Title: Can only afford to build 2. Performance questions
Post by: Steve Shafer on June 02, 2004, 09:51:35 PM

I can only afford to build two LAB Subs for my rig, and I am curious how they will perform.  When i am doing Dj work, I can stack the cabinets on top of each other and get the benefits of acoustic coupling.  However, when i am doing sound work, I will have to stack the mid/hi speakers on the lab subs.  The tops will either be EAW KF695e's or EV Qrx153/75's and I have a BSS 336 minidrive.

I have been told that a single LAB Sub drops off quite sharply below 50 hz. However, the modeling and specs that i have seen lead me to believe that the roll off will not be that drastic and that the drop off will occur lower than 50 hz.

For now, I will be powering one pair of LAB Subs with a Crown CE4000 running in bridged mono. Although this not a MA5002 or PL 6.0, it works well for most of the AC power situations that i get into.

The LAB's will be replacing two JBL SR4719a's. Clearly the LAB subs will put out more SPL.  However, when using one LAB Sub per side, will I notice a significant drop off in SPL below 40 hz?  The LAB Subs will definitely go lower than the JBL's, but will the out put below 40 hz be noticeable with the LAB's

Your advice and input would be greatly appreciated

Steve S

PS has anyone tried the new Magnum/Kilomax based Lab 12 driver??

Title: Re: Can only afford to build 2. Performance questions
Post by: Peter Sylvester on June 03, 2004, 08:45:54 PM

See my labhorn project site below for info on frequency response and EQ filters (under RTA section).  A little EQ can get you down to 32 Hz with a single box. As to whether 2 is enough it depends on the needed volume and room size. 2 happens to be more than enough for most things I do. I'd stack them side by side somewher in the middle, if you can.

http://home.comcast.net/~labhorn/

I've also built a couple of more conventional reflex bins using the Magnum 15LF.  Not even close to the LABs in output or efficiency, but a bit more portable, and they can go down to 35Hz or so:

http://home.comcast.net/~labhorn/minisub/

I've also just completed a set of tops, which use the Magnum 12HO for mids in a 2-way trap box (may put online at some point...)

--Peter

Title: Re: Can only afford to build 2. Performance questions
Post by: Tim Padrick on June 04, 2004, 01:17:11 PM

I've heard 1 LAB per side and 1 4917x per side in several rooms.  I think the LABs were better in every respect.