JTR Captivator - Page 132

I originall posted this in the general subwoofer forum, but thought I might get better feedback here:

My current subwoofer system consists of 4 Elemental Designs 190v2 18" drivers 2 each in sealed cabinets. The box measurments were recommended by ED when I made them. Each box is powered by a bridged QSC 2450, putting out around 2400 watts into 4 ohms. I use a velodyne SMS-1 for equalization. My front 3 speakers are Klipsch KL- 650 THX. The subs put out a prodigous amount of bass, I have measured up to 130db on certain scenes, but since I have put the system together I always felt like I wasn't getting the kind of mid bass that I should have and that the bass I am getting is very one note and bloated. I have tried adding 2 JTR growlers above 50hz (with a active crossover) to reinforce the mid-bass but I still feel like I am missing something. I have been tossing around the idea of getting a pair of the passive JTR ported captivators and running them off of the QSC's and dumping the ED's and growlers. My question is does anyone have any input on whether or not this will be an upgrade from my current system or am I even going to notice a difference? I really dont feel like building more boxes and going the DIY route again. Thanks in advance for the advice.

Sounds like a placement issue creating a null (or nulls) and killing the experience.

Might try changing placement before plunking down the cash for something that may not help. In my own experience, a pair of Captivators can be outgunned by high sensitivity speakers.

Even if your room setup can't support a permanent placement change, it may help understand if it's a placement or displacement issue.

Spot on RMK. If you want the Growler + sealed 18s to sing, you need an Omnimic or similar measurement capability, a DSP EQ with 2 or more separate outputs like a DCX-2496, and the time, interest, and persistence to get it working optimally.

I have been fine tuning my FR with my dual Cap S2's. Since the home theater GTG I have upgraded my AVR to a Denon 4311 so I could benefit from XT32. Posting 2 graphs and trying to figure out if getting flat to 5 Hz is worth it. So far I think it looks pretty good rolling off only 8 dB max from a peak at 25Hz to 5Hz. I have been reading all the posts about the ULF and the impact that a flat FR will have to 5Hz. Would appreciate input on a parametric EQ that would help me out. DCX2496 like Mark mentions above or a MiniDSP but have no experience with either.

Here are the OmniMic graphs. The first one has 2 lines. The blue line is 10dB higher than the red line. I wanted to see if there was any SPL difference in my room.



The second graph is with Audyssey on (red line) and off (blue line).



Let me know your thoughts.

David

Now use that response calibrated to your desired levels and play Tron, Immortals, WOTW, TIH, etc...Just the major scenes. Then add a LP at 20hz raising the low end 6-8 dBs with a 12db/octave. This should get you to flat to 5hz and then measure to make sure and then run the same scenes again. If you don't notice anything than don't use the LP, if you do than leave it, pretty simple right?

Will Parasound JC1 Single Channel Power Amplifiers, be a good match for the Captivator?

I prefer Parasound amps.

There are much better choices for powering a Captivator. You should be able to buy much more power for a lot less money.

I'am guessing that none of you have auditioned passive subs powered by Parasound amps.
I suggest that you do, then you'll know why I prefer there amplifiers.

I've listened to most of those high-end amps and none of them produced the bass slam,
that the Parasounds did.
The bass of the JC 1 is state of the art, riveting, jaw dropping.

Nobody does bass better than Parasound.

Try a Lab Gruppen.

The parasound is nowhere near powerfull enough to fully drive a captivator. The only slam I ever got from an amplifier was being hit by one.

You are certainly entitled to your opinion and are free to power the sub with any amp you like, but I'll never be convinced of any sonic advantage to using an amp like a Parasound with a sub. For me, it's pro-amps all the way for the sub power. I did power a passive sub for years with an old Parasound amp. It was an old D/AS 1000. Horrible experience. The amp overheated anytime it was pushed hard and would cycle off all the time. The best move I ever made was changing to a Behringer EP2500, fan modded. I've been using that amp for about 6 years now without a hitch. It cost me something like $279.00 and provides about 1400 watts bridged into 8ohms. It now powers my passive Captivator.

Now, Parasound for the main speakers I can understand.
Edited by mojomike - 9/20/12 at 9:31am

Actually that 1400 watts are for sine waves, for real material it would be higher. I have used Parasound amps for speakers as well and I have shut them down at reference many times, not the JC1 but their multichannel amps. I have never tried their best multichannel but it is a step down as far as power is concerned with my current multichannel amp. I have never heard bass like I do with my Lab clones and the reason for this is that they don't rolloff down low and provide huge power everywhere. I can blow up 12 1000 watt high excursion drivers with a single amp and this is a cheap clone of the real thing.

True, that 1400 watt rating is fairly conservative. Driving my Captivator, I really have to push hard to get clip lights to show and even then it's very brief.

That is good advice. For strictly bass duty, the Parasound is underpowered and over refined.

MK -- what do you mean add a LP at 20hz? Low Pass? How is putting a LP filter at 20hz going to help you maintain a flat curve to 5hz?

Does your newer DCX2496 let you do any manipulation of frequency response below 20hz?

I think he meant an LT not a LP.

With the DCX you add and LP and set it to 20hz. You control how much boost you want. Just measure after every gain and/or slope change. You will bring up under 20hz. I do it all the time.

Ok I give, what's LP stand for??

I think it is stands for Low Pass

In the DCX2496 software and the EQ section you can choose low shelf, high shelf, or parametric EQ filters. What MKTheater is using is the low shelf filter. When you enter the filters in directly using the unit's front panel controls, the EQ section says LP, HP, and parametric. It has them labeled wrong and really should say LS and HS instead of LP and HP.

MKTheater is choosing the LP filter, but is using a low shelf filter.

Correct, I forgot it was a shelf filter for a second. You choose(for EQ) LP, BP, or HP. BP is the normal parametric EQ. You can roll off highs, boost highs, and the same thing for lows. He has a little wiggle room(+/- 3 dBs to maintain a flat curve) so he can boost the low end where 10-20hz will be close to that top of that range and now 5hz will end up within that range making his graph now flat to 5hz. His 10-20hz range will be hotter but still within a FLAT region. Flat does not mean a straight line, it means a range. When I boost the low end like this to bring up 5hz it feels much stronger in my room and the need to run hot is not needed anymore. That is just me.

I'm still waiting on my powered Captivator to be shipped out from Jeff, if it's even done yet, that I ordered a month ago. I have a question for you guys about EQing. My AVR, a Pioneer, has the MCACC and not the XT-32 Audyssey program. I've been reading numerous post's that some of the other people are using a separate EQ just for their sub. Whether they have s SubM, Cap, or any other high end sub. Should I look into getting one of these units for my Captivator? If so, which would be a good brand to look at that won't break the bank? I don't know if I'll even need to do this, but the more digging I do makes me wonder if I should've even bought the Pioneer in the first place. Oh well, it's waaaay better then what I used to have. Nevertheless, the Integra 9.2 is definitely on my "next to purchase" list for sure.

I almost forgot, does anyone use the Behringer DSP1124? Any differences, pros/cons, anything?
Edited by MakeItLouder - 9/21/12 at 10:14am

I've done a lot of research on sub eq for the non XT32 crowd and personally decided on the Anti-mode for my S2. Pretty much nothing but good reports from everyone that actually owns one. Any "negative" info on the unit is people bashing the person for not just using an XT32 receiver. I don't have the sub or eq yet but I'll post my findings as soon as both show up.

Sounds good! Your in the same spot I'm in huh? Hurrying up to wait! Which EQ did you purchase?

Anti-mode my fault.

After quite a bit of internal debate, bordering on schizophrenia, I decided to go with the Anti-Mode 2.0 Dual Core for my bass eq. This is normally where I would be lambasted with 15 posts about how a 4311ci is a much better deal for it's current street price vs. the price of the dual core.

The primary reason I chose the dual core over XT32 is independence and customizability. I have a well treated (Erskine (Shawn more specifically) optimized) dedicated space. I am extremely happy with my (non LFE) sound without EQ. I have a fairly flat full range frequency response and good RT60 with only a mid base SPL bump on the L/R's at 120hz from the side walls....ahhhhh shucks . I have attempted setting up Audyssey XT on my Onkyo 805 many times following the guides here on AVS as close as possible and have never been impressed with the result. When measuring my frequency response with Omnimic it doesn't appear like XT is doing much in that realm (it didn't take out my mid base bump but flattened out some minor fluctuations a bit higher in the range) but it seems to suck the life out of my sound. I've heard XT32 is a big step forward but I'm unable to demo in my room and therefore I don't feel like taking a 1k+ experiment.

I'm not hear to start another Audyssey debate but the reason I'm bringing it up is that I personally don't like it and it's an all or nothing product in your AVR. You either run Audyssey EQ full range or you don't run it at all. I'd love to run the XT32 bass eq but if I don't like what it does to my mains and turn it off then I get nothing, that's a big mental block for me. With the dual core I get the same quality sub eq as XT32 but I can use it anywhere with any pre-pro with either system in my house and I have lots of customizability options, house curve, PEQ etc...

I chose the dual core over the standard option due to my personal setup. I will be integrating a Velodyne DD-15 with a JTR S2 in my room. The DD-15 has it's own DSP which introduces a unique delay to the signal when compared to the S2 which also has it's own DSP. Combine that with my desire to have ultimate flexibility in where I place the DD-15 and the dual core makes sense vs. the standard models. My subs are 75ft of cable length away from my rack through the attic and across many AC lines so the dual core's ability to take one RCA input and convert to two true balanced outputs is also attractive, especially for the S2, which has no RCA input; obviously not a deciding factor but a nice to have for sure.

Since I've received my omnimic system I've tried to manually eq the DD-15 in the time domain but it's a frustrating (and not as intuitive as it would seem) process and the idea of doing it twice with subs that have unique DSP delay and positioning to the primary seating position isn't appealing.

Ultimately, if you spend 20-50k to add 200-500sqft to your house for a dedicated HT. Then spend 10-15k on speakers and subs and other multiple k's on everything else in an attempt to achieve HT nirvanna I considered it a dis-service to the rest of my investment to not invest in high end sub eq.

This hobby and especially this site warps a man's sense of reality...I need to stop coming here!