After 39 of my own WSPR recordings at 14MHz were analysed yesterday, it's now possible to say that the latest JTDX update, which is not generally available at the moment, has a 2.7% better decode rate than WSJT-X 2.1.2.
[UPDATE 1: after an overnight listening session on 40m, the 2.7% improvement fell to just 0.5% with a much larger (1049) sample of decodes. WSJT-X managed to decode 1044 of these.
UPDATE 2: a roughly 18 hour listening session at 14MHz resulted in 728 decodes, 717 of which were decoded by WSJT-X, yielding a 1.5% advantage to JTDX.]
I had a look at which signals WSJT-X was failing to decode. It's all a bit odd, because there were two signals of -25 and -26dB, and one of +3dB. None of the signals were very close to other traces, so I can't figure out what WSJT-X is doing. The difference appears from time to time, regardless of how strong propagation is at that moment.
UPDATE: -30 and -31dB signals are being decoded regularly by JTDX now. It is also getting down to -34dB so far, which is as low as the alternative WSJT-X goes:
| 2019-11-29 13:20 | LA7EPA | 14.097191 | -34 | 0 | JP99of | 5 |

