# Summer home system refresh advice



## DS-21 (Apr 16, 2005)

've found myself with a little time to breathe, and I'm going to upgrade my mains. The main point of this upgrade, honestly, is aesthetic, because big grey studio monitors are ugly. But since I'm going to be spending the money on new cabinetry anyway and my new-to-me receiver (Denon AVR-4306, bought on impulse primarily for the Audyssey MultEQ XT and because it was a very good deal) has preouts that my prior receiver (Panny XR55) lacked, I thought maybe I could upgrade performance a bit, too. The drivers are set: the 12" Dual Concentrics from my current mains (Tannoy System 12 DMT II) with a Peerless XLS12 (830500) and XLS12-PR underneath each one. The crossover between woofer and tweeter in the Dual will probably be modified to suit the new cabinet, even though it will be roughly the same width as the 12 DMT II. (It will be sealed, and less deep.) The mains will be supplemented by a low-Q sealed sub - I got in on the Maelstrom-X preorder, and hopefully that driver will be an upgrade to my current Ava18 - presumably in "LFE+Main" (aka "DoubleBass" for Onkyo people) mode, powered by my current sub amp (Crown XTi2000).The electronic parts I could use in the course of this upgrade are as follows:

Velodyne SMS-1
2x NHT A1 monobloc
Dayton 240W plate amp
Panasonic XR55 (5ch in)
Adcom GFA-535II, GFA-2535, and GFA-5800

Here are four alternatives I've been pondering, from least to most complex and/or expensive:

1) Grow up. In truth, I feel like the Tannoys lack nothing, except that the DMT series cabinets are ungainly and ugly. And Audyssey has improved them further, sonically. BUT, more low-distortion displacement in the <150Hz range never hurt anyone, removing bass and thus excursion from the Duals certainly cannot hurt, more woofers might smooth out the bass response over a wider area, the cabinets won't cost much more considering that the centers of the Duals will be at ~54" off the floor anyway based on listening experimentation, and it's kind of sad to think that all of this cool stuff is just sitting idle. So the mature, reasonable option is probably a non-starter. 

2) Use the internal bass management in the 4306 to roll off the Duals at ~150Hz, and feed both the XLS12's and the 18" sub off of the sub-out on the receiver. I could use the XTi2000's built in crossover to roll off the big sub earlier, if placement requires it. This option would be my favorite, as I could do it without buying any more electronics. I am, however, a little concerned about going mono below 150Hz. Also, I was hoping that with the receiver I could sell my SMS-1 because of the Audyssey's bass EQ, but for this option to work I think I'd need it because I doubt the 4306's sub out could drive 3 amps, one of which balanced.

3) Set the sub crossover to 80Hz or so for the sub, and biamp the mains using the Denon's built-in amps for the Duals (with passive HP), and active for the XLS12's. The XLS12's would get signal from the mains preouts, and the sub from the sub-out. In this option, I'd probably buy two more of the Dayton 240W plate amps, simply because they're cheap and work well with the XLS12 IME. I'm not worried about designing the HP for the Duals, and I'm pretty sure I could sell the SMS-1 if I go this route.

4) Use the 4306 as pre-pro only, with active crossovers between the Duals and the XLS12's. There are several routes I could go here. 
4a) The easiest (and most expensive) would probably be to buy three Crown XTi1000's, using their crossover and EQ functions. I think that would be the best route, but I neither want to spend the money required nor, truth be told, do I want four silver amps (these plus my current XTi2000) staring me in the face.
4b) Alternately, I could go with a Behringer DCX and use my existing amps (or maybe buy a third NHT A1 for the XLS12's and use the 2535 for the Duals), but I've read through 6 pages of threads on that unit here and the indications seem to be that I'd need a volume control between the DCX and the amps. For obvious reasons in a 5.1 (5.4?) channel setup, I'm unwilling to consider that. And then there's the whole balanced input thing... 
4c) I would also be willing to consider use of a "car" speaker management system, such as the AudioControl DQXS. (I used an AudioControl 24XS car unit in a previous system design, and it worked fine.)
4d) Did I miss something easy and obvious?

So which alternative would you choose, and why?


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## 60ndown (Feb 8, 2007)

cliff notes?


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## DS-21 (Apr 16, 2005)

60ndown said:


> cliff notes?


You guys know me better than that by now! 



Autiophile said:


> I'd go with option 3. In my eyes you gain quite a bit of flexibility compared to option 2. Option 2 is attractive because of the lower cost, but I too would be concerned about going mono around 150hz.


After happening upon and reading through this thread ( specifically, this post I'm beginning to think that (1) I'm in damn good company in thinking that smallish closed box "sats" with big cone area and limited bass response is the way to go; and (2) maybe 150Hz is too conservative. After all, Tannoy themselves seem to think that 100Hz is a good point to cross a 12" dual to a supporting woofer. (Kingdom brochure.) I'm comfortable with 100Hz and below being in mono, I think. (The big sub would come in lower, presumably.) 

Also, if I find another Tannoy CPA-12 (or better yet the 3133 Dual Concentric driver in it), I might pick it up. (I have two in my cellar already; they come out when friends throw garden parties and such.) They're even more efficient (~99dB/w/m) with correspondingly lesser bass performance. In a sealed box, they roll off pretty much just like the 10" B&C woofer in Dr. Geddes' kit.


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