Thiel 1.6 vs. 2.4 vs. 3.6 using NAD c372

From NAD's website on the 372:
2 x 150W Minimum Continuous Power into 4/8 ohms
220W, 340W, 460W IHF Dynamic Power into 8, 4 and 2 ohms, respectively

I would not consider the IHF figure but only the continuous number.

I'm just a bit concerned that you might be disappointed simply because the NAD will not provide sufficient current to appropriately power the Thiels, regardless of model you are considering. I see the amp is capable of delivering 150W into 4 Ohms and that could be sufficient as long as you don't have unrealistic expectations regarding high SPLs in a large room with this set up. But as you said your room is relatively small. But rooms change with life.

The usual result is that folks end up underpowering them, not the watts mind you, and then blame the Thiels for sounding bright. Thiels do not sound bright at all, but will if underpowered by an amp that cannot swing the current needed. Thiels like amps that double power as impedance halves. That said, the minimum impedances for the models you mentioned are: 1.6: 3.0 Ohms; 2.4: 3.0 Ohms; 3.6: 2.5 Ohms.

I think your best bet would be the 2.4 as it will have better bass response than the 1.6 but be an easier load to drive than the 3.6.

Also, you can always work towards upgrading your amp in the future so I would go with the larger 2.4 model, space and budget permitting. By the way I am a Thiel owner (6s) and found that even Bryston 7BSTs, as good as they are, and they are good amps, could not power the Thiels the way a Krell 400cx does. This made a major improvement in everything the Thiels can do sonically.

Alternatively, you could consider Vandersteen 2Ces. I also own these and they are IMHO, the best speaker value for the money and. like Thiel, are time and phase accurate. They would also be a great match for the NAD as they are easier to drive than the Thiels.

Let us know what you decide to do. Cheers!
Steve

Go for the 2.4's. The 3.6's are too much for your room. The 1.6's that I heard can't touch the 2.4's in any area.

The big question is, what are your future intentions? If you intend to stick with the NAD, the Thiels are probably too high end for what you're doing. The 2.4's are going to require extremely good power, and lots of it. If you are going to be willing to step up your amp, the Musical Fidelity KW500 integrated is just one of many good matches for the Thiels.

Check the ohm rating factor across the spectrum for all the Thiels, some of which which can be pretty demanding on a small amp's current capabilities. Your NAD might not be able to deliver a powerful signal clean enough to prevent frying itself, the drivers or your ears.

Thiels are notoriously accurate and unforgiving of sources and electronics -- tend to show up any harshness along the chain, and can be fatiguing. If you're in love with accuracy but want to soften the high end a bit, and have the money, look into the heftier c-j tube stuff.

If the NAD must stay, look into something easier to drive, whose resistance doesn't drop much below 4 ohms.

Putting speakers along the long wall is not so bad, depending on boundary reflections (I must do this, too). Just keep them well out in the room if possible.

I use Thiel CS 3.6 driven by Forte 4A which, though rated at 50 amps, is Class A and apparently provides enough current to tame these beasts even for Mahler -- though I hasten to add my room is only 22 x 14 x 9 and I don't play the system terribly loud.

Cannot comment on price differential, except to speculate on relative popularity.