Building a 2 channel system

[Rondar]

I have a fair home theater system currently. I have a marantz 5300 used as a pre amp for the front left and right speakers, and the marantz amps powering the other three. The main speakers are currently powered by and
Adcom GFA 550 power amp, as that is what I had last year powering my 2 magnepan smga's. Since October I have bought 2 MFWs, pair of X-tatics bstock and a Marantz 5300 from AV123. I also bought 3 X-CS speakers from a forum member and use one of these for center and other 2 for surrounds, and a sony bd-350 from a av123 forum member.

I had thought of buying an Emotiva XPA-5 Amp for the home theater, then taking the Adcom and using it for a 2 channel system, since I already have it. This is where I stand currently. I have no knowledge of these dac's you guys talk about or what they do. In the past, when I had a cheap cheap 100 dollar sub I hooked it up to the magnepans I had via speaker level inputs. If I were to build another 2 channel system this summer, is there a better way to hook up a sub for 2 channel? I know I am going to need a preamp of some sort and sources, do they have lfe or sub outs?

I'm still trying to learn all of this stuff. I live at least 200 miles from anywhere I can walk in and talk to a live person. 20 years ago I was kinda on top of all the electronics and what they did, but got realistically clear out of it while raising my family. Now, there has been a lot, A LOT of changes, and no one in or around our town of 800 good folks have much of a clue either.

It might turn out that all I may need is a bookshelf system with a small sub. Maybe the Gizmo, DAC ( is this a preamp so to speak?) and a cd player or something is all I might need, and then I sell my Adcom. I still have my Maggie smga's in storage in my basement, maybe I need to sell them too.

Ahhh well, all this gives me some things to think about while working and out driving a tractor here on the farm. Radio tends to get really boring day after day.

[chessman]

Rondar,

A "DAC" is, strictly speaking, a digital to analog converter, typically in the form of a computer chip. More generally, it is a device that includes the chip and an analog output stage and various "extras."

All CD players and receivers have a DAC built in. So, why buy an external one? The idea is to obtain higher grade components and perhaps a better implementation. I think of it as similar to hot-rodding a car.

Does a DAC make a difference in sound quality? You defnitely have to trust your own ears on this one. Discussions on the topic range from "all DACs sound alike, go cheap or not at all" to "a veil was lifted." Most of the debate stems from the participants having different definitions of what a DAC consits of.

My own experience is that a DAC made a big difference for me. Because the DAC had its own power supply, had a "reclocker" implemented as one of the "extras" mentioned above, and a hand built analog stage, the resulting sound, for my ears in my room, sounded much more lifelike and much less like the artificial tone that my ears assign to digital. So for me, "a veil was lifted." :thumbsup:

[Jason]

Generally speaking, an outboard dac will outperform the built in dac's on most players. Exceptions may be a cdp that has had it's internal dac modded like Craig's.

First off, congrats on the decision to have a dedicated 2 channel rig. I think you will find it immensely enjoyable, and vastly superior to listening to music in your HT. As far as preamps, there are many out there that have 2 sets of outputs (my Rogue Perseus is one example). You can run one output to a sub, and the other to your main amp.

As far as crossovers for using a sub, one way is to add an outboard crossover such as the Outlaw ICBM. They don't make those anymore, but come up used from time to time. An option I'm looking into is a Behringer DCX2496. It is extremely flexible, and some folks are using it to actively bi and tri amp their speakers (vmps for instance). Some subs also have built in high pass circuits, although I question their fidelity. I'm using the high pass on a PB13 right now.

First thing's first....get a budget lined out (as best you can) and we can give you some suggestions from there. (I say we, there are many here more knowledgeable than me...)

[django1]

My buddy has some Magnepan and we hooked them up with my x-sub: a great combination.
The gizmo or any of the low powered t-amps will do better in a small room.

I have a t-amp, a run of the mill dvd player, the non usb version of this dac (around $80)http://www.obadimports.com/catalog/i...55/6829249.htm, x-ls encore and x-sub. The result is a fairly cheap system that kicks butt. When I got my present t-amp ( billnchristy-Dweekie design), my Magnepan buddy, whose regular system is quad amp-pre-amp with a decent cdp, 300$ dac and Spendor speakers, listened to my little system with his mouth agape...

[NekoAudio]

Magnepan's are great. That's what I use in my current 2-channel music setup. The only thing I've heard and liked better is a pair of Analysis Audio full-range ribbons driven by a Spectron Musician III amp.

My Setup
Transports: Denon DVD-1710 and AirPort Express
Audio Chain: Neko Audio D100 DAC -> Anthem TLP-1 -> Wyred 4 Sound ST-500
Speakers: Magnepan 1.6 and DIY subwoofers (Behringer DCX2496 + EP2500).

As an aside, I cannot run Magnepan 3.6 or 20.1 because my subwoofer would blow out their ribbons. The 1.6 uses aluminum quasi-ribbons. I will say I didn't like the 12's or lower so much though.

I use the Anthem for speaker/sub crossover. I don't want the main speaker audio to go through the DCX2496 signal processing. Another option with a crossover is the Parasound Classic 2100. And the new Wyred 4 Sound STP. There are tons of other choices, but they're somewhat more esoteric. PS Audio's pre-amp with crossover is discontinued, IIRC.

[Jason]

Wes,

How/why would your sub blow out the ribbon? I've never heard of this effect before...

I too like the 1.6's...I heard them in a fabulous setup in Dallas. Audio Research SP16 (I think) and a SS 100 watt x2 Audio Research amp (can't remember the model). Source was Arcam. Wonderful system.

[NekoAudio]

Because my subs are capable of 115dB @ 5Hz @ 3m, in room. :p

A strong wind is capable of damaging a ribbon, but normally you don't have strong winds in your home. I called Magnepan to ask. If I was placing the Magnepans some distance away from my subs, the ribbons in a 3.6 or 20.1 would probably be okay. But the person I spoke to advised against using those models since I'd be placing them within a few feet of my subs. The aluminum quasi-ribbons are much stronger than the true ribbons.

[Jason]

Because my subs are capable of 115dB @ 5Hz @ 3m, in room. :p

A strong wind is capable of damaging a ribbon, but normally you don't have strong winds in your home. I called Magnepan to ask. If I was placing the Magnepans some distance away from my subs, the ribbons in a 3.6 or 20.1 would probably be okay. But the person I spoke to advised against using those models since I'd be placing them within a few feet of my subs. The aluminum quasi-ribbons are much stronger than the true ribbons.

Cool...what subs are you running...I'm guessing DIY?

I don't have any problems with my Eminent Tech's. I don't have the sub power you do either (just a single PB13) but I don't think I'd have a problem anyway. The membranes on mine are mylar with aluminum foil voice coil traces.

[NekoAudio]

Yes, DIY. They're two sealed sonotube subwoofers, four 15" TC-2000 drivers total. Driven by an EP2500 and a DCX2496 simulating a Linkwitz Transform for low frequency boost.

[Jason]

Cool...I bet it's impressive.

Man...I'm reading a lot more recently about that 2496. Ed M at SVS recommended one, and I'm reading that the VMPS guys are using it to actively bi and tri amp their stuff.

So do your big subs keep pace well with the 1.6's??

[NekoAudio]

Yeah. The group delay is very low. The EP2500 provides enough power and current and the drivers are high quality so transients are quick and precise.

Of course, the 1.6's won't play very loud to begin with. But the subs are also used with my HT setup, which will play loud. The DCX2496 lets me sum two inputs.