Gauss and the 5 string T39

[Gauss]

I just got back from running sound for a 5k with my friend and his system. We took the T39 to compare it with his JRX100's by JBL. The subs are compact 18" rated for 350w continuous. I've always liked this system, and thought it had more juice than we needed, even outside like we were today. With this system, the subs support the tops, so they are designed to be split, and the bass power alley was where we were standing. I walked around and sure enough, there were areas with no bass.

While the runners were out running, we set up the subs to a/b mine with one of his while the tops carried on as normal. I was disappointed that the T39 wasn't louder. I walked up to it and the bass sounded great, clean and low, but the volume was lacking. My friend's verdict: "Your sub is clean and low with just lows, my sub is loud and has higher frequencies." I tried to "hear" just sub-level frequencies, but I couldn't really block out the others and I could hear the bass and kick very loudly. At the end of the event, I hooked up the T39 to check it again and then cranked the bass up to better match the volume of the tops and I got what I wanted - nice and clear bass, but I had to add an extra 12db of EQ to make it heard with the mains. (On the other hand, at this point I was replacing two 18" subs.)

So now I wonder whether I have an air-leak that is compromising my volume, or if my low frequency observation is poor. My T39 sounds huge with my bass and when I use the built-in passive crossover to play music, but with a steep active crossover at 80 hz, it takes a lot of power to get loud. Next time, I'll compare them indoors, where low end is easier to sustain than mid-lows.

Edit: I spent the day outside with my own personal concert, I'm sure there's no air-leak. A/B'ing it with my bass cab with sine waves showed me that it's more sensitive than my combo amp. The problem is simply the upper frequencies overrunning the lower ones. I disconnected the high and cranked the lows - it was scary loud, I thought something was going to break. Next time I'll not be afraid to goose the lows to match the perceived output of a direct reflex box.

[Bill Fitzmaurice]

Your friend is right.
http://billfitzmaurice.net/phpBB3/viewt ... f=10&t=999

[Gauss]

I had another chance to use my Titan39 and wanted to share. We had a special worship service at my church, in the gym, which gets converted for services with carpet tiles, and pipe & drape. We played a lot of contemporary Christian music with a lot of dynamics (i.e. building chorus, then full-on volume chorus to acapella chorus). I used a combo amp with my T39, wall-loaded behind the stage, and only had the mids and highs run through the PA for better dispersion. The Titan39 was more than capable of filling the room. At the apex of one song (Jesus Paid It All), I play the riff an octave under, starting on C, and the room just shook. It was amazing to have so much power so low.

When I was testing to see if the sub could fill the room without the two 2x15 EAWs that were part of the PA. No problem. The rafters, air ducts and lights were all rattling. I put on some dance music with an mp3 player and have no doubt I could DJ a dance in a gym with this sub alone. My friend reported chest thump about 35 feet from the sub. The amp was 120 watts (Hartke Kickback12), and I was well below max output.

[Gauss]

Another update. I love this sub. There was another church event for the youth, and I brought my MP3 player and my T39. I plugged the MP3 player into the overhead speaker system in the gym (usually just for vocals), and ran the aux ouput into the T39. After some careful adjustments between the channel EQ and the stereo EQ to keep the mids out of the sub(the passive crossover isn't too hot at high volumes) I rocked the gym all night. We had 4 giant inflatables in there, driven by 8 noisy blowers, but the bass was still clear and pumping, even down the hall. This box is amazing. It was very unpleasant to be next to, because of volume, but the whole room was full of bass.

[Gauss]

I finally had the chance to properly crossover the sub for a DJ gig in a gym. It was incredible. The clarity and power blew me away. I set it up to be flat with the EQ, high-passed to protect the driver and low-passed to keep out the mids, and it was invisible. You couldn't tell where that thunderous low-end was coming from. It was way too loud for me 15 feet away (in the corner), thumping my chest and blurring my sight, but crystal clear. Next time my earplugs will be a must. I did have to push the low end louder to get the mix I wanted with the JBL tops (same as used before, jrx series, 15 inch tops), but the subwoofer had lows to give.

[gdougherty]

I finally had the chance to properly crossover the sub for a DJ gig in a gym. It was incredible. The clarity and power blew me away. I set it up to be flat with the EQ, high-passed to protect the driver and low-passed to keep out the mids, and it was invisible. You couldn't tell where that thunderous low-end was coming from. It was way too loud for me 15 feet away (in the corner), thumping my chest and blurring my sight, but crystal clear. Next time my earplugs will be a must. I did have to push the low end louder to get the mix I wanted with the JBL tops (same as used before, jrx series, 15 inch tops), but the subwoofer had lows to give.

Now you just need a second for those gyms.

[Israel]

[quote="Gauss"][/quote]
Genz Benz rule