Summary:
I wanted a sub for music. I listened to all of the those listed. I bought the ACI Titan based upon reading reviews here, magazine reviews, and the ACI website. Found a good deal on a used one. The warranty is transferrable if you can verify the original owner. ACI staff were helpful and I ordered the spikes and some cable for it at a fair price.

This sub has great presence and musicality. You can actually hear the instruments rather than a muffled thud sound so common to many subs. It adds a very subtle, smooth, and understated depth to all recordings. It can get loud if you like that. I am sure it will do HT just fine.
Setup and placement does not seem to be very difficult.
I am very happy with my purchase and am considering other ACI products.
The only sub that sounded as musical was the Monitor Audio 110, but it did not have the overall depth of the Titan.
This is a great sub.

Strengths:
Build quality, accuracy, musicality.

Weaknesses:
Control knobs need better markings in order to see easier.
This is a heavy sub and rather large if that is an issue.

Similar Products Used:
Listened to: Velodyne CT100 and CT120, Paradigm PDR 10 and PDR12,PS1000,PSW 2200 and Servo 15; Polk 450 and 650, Monitor Audio 110.

Summary:
Titan Diary:

Monday 3/3/00

Got this sub primarily on the basis of reviews at this site. I have Maggie MMGs (I’m upgrading to 1.6s) so I wanted a subwoofer that was fast, tight and musical for not a lot of money. The REL Strata III was my first choice, but my finances said no.

Shipping box was packed well, despite a few dings on the outside of the box the sub itself was intact. The oak wood finish was nice, but the overall impression was not as elegant as it looks in the photographs. Put spikes on the bottom, ran an RCA plug from the subwoofer-out on my receiver, set the crossover at 70 Hz, plugged it in, turned it on and….

Disappointed. Don’t buy this sub for instant gratification. Out of the box it sounds muffled and ill defined. You can tell there is depth and power, but initially there is no articulation and doesn’t integrate with music. ACI says they should burn in for at least 60 hours. Each day before I left for work I put on a bass-heavy CD on random play, set the crossover at 150Hz, and turned up the volume as loud as I could without feeling guilty. (I live in a studio apartment, and leave for work at 6:45 am).

First configuration used “sub out” on my Denon Receiver, but I obtained the best results sound by using Y-connectors from the preamp outputs for the left and right channels. One side of each Y went to the subwoofer, while the other side went to a highpass 65Hz RCA plug filter from ACI, which in turn plugged into to an Outlaw 750. Some people object to the high-pass filters, I found that they opened up the sound from the Maggies. They also (to my hears) help smooth the transition from the sub to the mains.

Thursday 3/7/00

After running the sub for 3 days it is finally starting to sound like something other than an $800 bowl of Jell-O. I watched a DVD with a lot of low FX noise, and it sounded deep and powerful, without being obtrusive. But low frequency FX is the easiest job a sub has to perform, the true test (and the most important to my ears) is music. Listening to Diana Krall’s “Love Scenes” the sub was starting to become more musical, the bottom notes showing some definition.

Friday 3/8/00

Received an email reply from Mike Dzurko today about wiring configuration. Customer service gets a gold star.

Sunday 3/10/2000

Setting the EQ to about 70 Hz provided a relatively smooth transition in terms of volume (there’s no “bump” at the seam between the speaker low end and the sub high end). After running the sub constantly for a week, I thought it would be sounding better than it is. There just isn’t very good integration between the Maggies and the Titan, at least so far. The sub is deep with plenty of power to rattle the walls, if you are so inclined. Handles DVD FX tracks with aplomb, but falls short when trying to convince me that music is being made by a musical instrument.

Tuesday 2/11/2000

I have to make up my mind soon. This is nervous time. Have I given the sub enough of a break-in? Will it sound better over time? My most nagging doubt is that there is someplace else I could spend $800 and enjoy my music more.

Wednesay 2/12/2000

Gave the Titan a last listen tonight. It IS blending better, but not quite enough. Bass notes still sound like “thump” instead of “thrum”. I made the decision to send it back. It was tough decision, but I had to ask myself if it increased my audio enjoyment by $800, and the answer was no.

To ACI’s credit, they handled the return with no questions asked. Their customer service has been first-rate.

All of this is subjective, and your results may vary. If you live in an unattached dwelling, watch a lot of DVDs, listen to cone speakers instead of planars, and can really let the sub work, you might very well love the Titan. I’m certainly not going to knock this product: It is handsome, appears to be well made, and powerful. But trying to match it with Magneplanars in a studio apartment was like asking a weight lifter to walk a balance beam. It had depth and power, but not enough grace. Possibly some of this was due to limited placement opportunities in a studio apartment, but it wasn’t a good match for what was important to me. It could very well be that it would have sounded better over time, but I wasn’t prepared to risk $800 to find out.

Equipment used:

Denon AVR-1800 Receiver (As preamp)
Outlaw 750 Amplifier
Magneplanar MMG front surround/stereo speakers with 65 Hz highpass filters from ACI
(floor stand and tweeter attenuator tweaks)
Sound Dynamics RTS-C2 Center Channel
Sound Dynamics RTS–3 Rear Surrounds
Y-connector cables from Bettercables.com
DH Labs Silver Sonic T-14 & BL-1 cables
Cambridge Audio D500 CD player
Toshiba 3109 DVD player

Strengths:
Customer service fit and finish, construction, power

Weaknesses:
Was just not musical enough

Similar Products Used:
First Dedicated subwoofer

Summary:
I recently purchased this sub for ACI and after
an anxious 5 days of waiting for UPS to deliver it
I now have about 20 hours of listening of music
and movies. I am extremely satisfied with the performance
thus far and as ACI recommends 60 hours of break in before
evaluation of this sub I can only imagine that I will become
happier and happier. After reading all the reviews in here
and looking around at other subs I basically purchased
the Titan on faith and though I am an extremely cautious consumer (and frankly I doubftul of reviews in here as I am
sure some are biased) I felt like I was making the correct
purchase. My System:

Denon AVR2700
Paradigm Studio Reference 60's
Sony CD7ES (?) 5-disc changer
VHS (I can't remember the brand) 4 head generic deal.
Panasonic 27" T.V.

The Titan definately integrated easily for music rounding
out the bottom octave perfectly. I am no audiophile snob
but I can say the ACI Titan is well worth the 799 dollars +
DH Labs cable. I was able to receive spousal approval as well which was an added bonus you cannot put a price on
as you already know I am sure.
Life is good.
As they say, "If the house is a rockin' don't bother knockin'" has taken on an added meaning.

Strengths:
Musicality,easy integration with mains,appearance,
the wife factor

Weaknesses:
None that I can honestly say I find

Similar Products Used:
Velodyne,Klipsch,Bose

Summary:
Based on the review that the Optimus 15" sub was better than a Titan, I went and tried one out. First of all, its very ugly And the bass is very sloppy.
Its not much louder than the titan.

As for the Titan, Be sure not to eat to much before watching the Matrix with this baby hooked up!
It matches very nice with the Emeralds.

Strengths:
None (Optimus 15")

Weaknesses:
Lots (Optimus 15")

Similar Products Used:
Tian, Emereads, B&W 901, Optimus 15" sub Cambridge soundworks BC12 and BC10.

Summary:
The Titans are not the deepest or loudest for the money, but I do believe they are the best sound for the money. If you need a sub to go higher than 70Hz there are little alternatives. The Titan integrates with my main speakers very well. Basically the Titan is one of the few subs that sounds good with music.

Strengths:
The Titans main strength is its sound quality. It actually sounds good with music.

Weaknesses:
It doesn't go down to 14 Hz, but is that neccissary?

Similar Products Used:
I have owned a Velodyne ULD-15 and a JBL PSW-1200. I was a salesman a few years back and I sold various subs from Paradigm, Energy, Sound Dynamic, NHT, and Sunfire.