Review

Based on the same platform as the SDG1000X up to the SDG6000X this is the middle man, offering way more than the SDG1000X especially in light of sample memory, sample rate and important freq. stability. The touchscreen is an afterthought and in my opinion not of a good use as it is also resistive. The GUI is simply noot up to touch operations all through. Anyway, enough buttons and all the ops quirks of these series (well documented on the web). Signal fidelity is quite good and so is freq. stability. These series have the unforutnate double/triple use of external connections (sync/ext.mod/ref.in-out etc..) thus if you want sync. out on CH1 and CH2 you are out of luck. Goes for the whole series 1k to 6k. The omission of a few more BNC's is hardly excusable and limits practibility. Dual tone out for IMD measurements take consideration that the internal combiner is not that good. External combiners recommended. However, this is a WF generator and not a Signal Generator. One needs to pay attention to that, even if buying the 120MHz version. For instance the SDG6000X suffers the same fate just at higher freq's. It still is perhaps an economic solution for higher freq. generation, but not so good at 500MHz for instance. Simply, the more you pay the better it gets.
The SDG2000X now (this is already my second one) has gotten a little less noisy (from the internal FAN) but still Siglent should incorporate a regulated fan circuit, cannot be that hard. Internal counter (a little goodie) is quite precise (oh well, depending on its internal f ref.) Would be good to have some graphics for long term statistics. Surprisingly my SDG2042X surpasses its spec's in terms of lower freq. (up to 1MHz). I measured a THD of 0.0008 to 0.001% (sine 1kHz & 10kHz) which makes this a good source for audio related measurements. NF goes down to -95dBc which is really good so far. Jitter even on higher freq. is not so bad. Mind one limitation though! The 1.25Gs/s is in really a 4x oversampled figure. (Marketing blabla) And in TrueArb mode it stops at 75Ms/s.
All in all a capable unit with an upgrade path up to 120MHz (only sine wave!). I had previous problems of PWM mod. signals whilst changing paramters on the fly having spikes & drops (another brand) which is unusable. For the SDG2000X I can confirm it is clean in this particular test scenario.
And of course the biggest praise goes to Eleshop NL. They simply are totally customer oriented, have very fast delivery times and even in case of problems are very fast responders. I cannot praise them enough and highly recommend the team!