Table 1.

Statistical analysis of the RMS amplitudes of t₁ noise and random noise, and the amplitude of a genuine cross-peak in the selected regions shown in Fig 3. The 8 × 8-scan co-addition method has the same total acquisition time as the conventional 64-scan method. Datasets (conventional and co-add) labeled with #1 were acquired sequentially together. Datasets #2 and #3 were acquired together but at a different time from #1. 8 × 8-scan co-addition method led to more than 75% reduction of t₁ noise over the conventional 64-scan method, partly because its individual 8-scan spectrum can achieve about 50% t₁ reduction in this region. The complete data entries can be found in Table S1.

Lysozyme NOESY	Percent RMS of t1 noise*	Percept RMS of random noise*	Percent intensity of an a genuine peak*
64-scan #1	0.34	0.004	0.43
64-scan #2	0.90	0.004	0.40
64-scan #2	0.60	0.004	0.40
8 × 8-scan #1	0.08	0.004	0.42
8 × 8-scan #2	0.16	0.004	0.40
8 × 8-scan #3	0.10	0.004	0.39
8-scan #1 (8 sets)	0.16 +/- 0.04	0.01 +/- 0.0005	0.41 +/-0.04
8-scan #2 (8 sets)	0.20 +/- 0.03	0.01 +/- 0.0006	0.42 +/- 0.1
8-scan #3 (8 sets)	0.16 +/- 0.07	0.01 +/- 0.0005	0.42 +/- 0.1

^*: Normalized by the max intensity of diagonal region with F2: -0.71 to -0.77 ppm and F1: -0.71 to -0.77 ppm