Over on the SDRplay forum, Paul NN4F shares his results where he compares the LF (Longwave) performance of the RSPdx with a number of  popular SDRs.

He writes:

Ok as some of you may know, I started the facebook group for SDRPlay as an unofficial group, then I started working for ELAD, but I continued to be a tester for SDRPlay, over the past few years, I’ve managed to gather a small collection of SDR’s , all the SDRPlay Range from the 1 to the latest RSPdx, and obviously all the ELAD Radios, well I do work for them… 🙂 and a few more, including the revered Perseus.

Last night the LW signals work amazing here, so I decided to do a comparison test, trying not to be biased towards Elad, but they are in a different price range, the next step up from SDRPlay SDR’s My Location is just outside of Charleston, SC in the USA, and the target station was Medi1 out of Morocco on 171kHz

All signals just above the noise floor,

Perseus Just about see the signal, audio is just about readable,

Airspy HF+ barely see the signal, can tell audio is there but can’t make it out.

LimeSDR hmmm joke waste of my money

Elad S2 just about hear and see the station, readable

RSP1 Nothing

RSP1a just about hear and see, just about readable almost as good as the Perseus

RSPDuo Similar to RSP1a

RSP2Pro worse than 1a to be expected I guess

RSPdx good signal and almost perfectly readable

Elad S3 just a wee tad better than the RSPdx, clear audio ($800 more)

Elad DuoR using SW2 about on par with RSPdx ($700 more)

Using 120ft longwire via a 9:1 grounded, couldn’t compare S3 in Uno as extio’s are not available yet (Radio isn’t publicly available yet)…all tested at about 500khz Bandwidth or as close to. I do have better antennas but this was the setup at the time

RSPdx was in HDR mode LW button, then improved signal by using LIF 1.536mhz at 16 decimation 200khz and it was that was closest to Elad-S3 and better than the RSPDuo

All with noise floor around s5, signal showing around s6-8

So in order of best to worst

Elad-S3, RSPdx, Elad DuoR, Elad-S2(add-on filters not used), Perseus, (RSP1a, RSPDuo Both about same) Elad-S1, Airspy HF+, RSP1, LimeSDR

This isn’t a LAB grade test, it was made using the MK1 Brain, Eyes and Ears, We could go into details, but whats 0.1 of a dB between friends…..and if you can’t hear the station, what’s the point of all the noise figures…

Pic is the RSPdx using latest 1.33 SDRUno using HDR mode on Antenna C”