Chris & Token: Thanks for the comments! That helps a lot. I was looking at reviews last night & saw a lot of positives on the SDR-IQ, but also saw a number of people who said that it was much noisier than the typical receiver. Do many of these receivers stack up well against the older contingent of top-end hobby-level radios (e.g., R-8, R-5000, ICR-71, NRD-525)?
Thanks again!
The Perseus and especially the Excalibur will compete favorably with any of the older top end hobby level radios, indeed any hobby level radio from any time period. Since getting my Excalibur I only turn on the R71, R75, or the NRD-525 when I need another freq watched, in fact the R71 and -525 are not even on my primary listening bench anymore, being back in the radio room instead (my primary listening area is in the living room). I have used the Net-SDR also and find it very good, but have no idea how it technically compares, I did not use it on my own bench next to my other equipment.
In my opinion I think the Excalibur is better than the Perseus, and yes I do have both of them. They are side-by side here but I use the Excalibur daily, and I just leave the Perseus on my remote node for other people to use. I use the SDR-IQ's for watching spot freqs and doing scheduled recordings,a nd one of them stays online 24/7 for other people to use as a remote. The Excalibur Pro (G33DDC) is even better than the Excalibur (G31DDC), but is almost twice the price. Again my opinion, but unless you need remote control operation the Excalibur or the Excalibur Pro is the best hobby RX, SDR or traditional, on the market today. If you need or want remote operation then the Perseus or the Net-SDR / SDR-IP might be the best choice, possibly not quite as good as the Excalibur (that could be argued in either direction), but the Excal cannot be remoted. The Excalibur Pro can be remoted, but that is a $200 option.
If you want to see how the numbers stack up (for RX performance) a good resource is the Sherwood Engineering table of measurements:
http://www.sherweng.com/table.htmlNote that not everything is on there, and the table is sorted on 3rd order narrow spaced dynamic range, a good indicator but not the only thing that makes a receiver good. The list is long and well done, but naturally not complete, every radio just cannot be on it. Note that the Excalibur is not on the list, and neither are any of the RFSpace pieces of hardware, they have not been tested. But, the Perseus is on the list, and you can see that it compares well. And, as I said, the Excalibur is even better, in my opinion as well as in several measurable specifications.
As for the SDR-IQ and noise, it is a low cost option so it is not a top performer. It still performs well but one of the areas it is a little lacking is a higher noise floor than the more expensive units. This is not bad at all, just not as “good”. If you are talking about noise in the audio that is going to depend a bit on your computers sound setup. I have seen people complain about the audio not sounding good, maybe being sharp and harsh, but then hearing another SDR-IQ and saying that one sounds good. The speakers and sound card in your computer will shape the sound, so not every installation will sound the same. A good set of speakers / headphones will make it sound better, and a low end sound card can kill it.
I would have to say that in general I find the SDRs to NOT have as good sound as a good traditional RX. If sound quality is your driving criteria you might not be as happy with an SDR.
If noise floor is the driver for you then the SDR-IQ is not going to be great, while the better SDR units will be good. The Excalibur has a noise floor of about –131 dBm, the Excalibur Pro about –135 dBm (both from my own measurements, but in line with WinRadios published performance figures). The Perseus is a bit worse than this, at about –125 to –127 dBm. The R5000 has a noise floor of about –131 dBm (Sherwood list), the R-71A has a noise floor of about –135 dBm (Sherwood list), the Drake R8 is about –131 dBm (Sherwood list), and the NRD-525 is about –132 dBm (Sherwood list). All of these radios will show a noise floor that is below the average ambient noise at almost any listening location.
The Excalibur (G31DDC) sensitivity is also in line with most of those radios, and the Excalibur Pro (G33DDC) is more sensitive than the G31DDC, equaling or beating the best of the traditional radios above. The Perseus will have the worst sensitivity of the bunch listed, but not bad. The SDR-IQ will be worse than the Perseus in pretty much every category, but it is also about half the price.
In performance the upper end SDRs are great, better than any hobby grade RX on the market today and probably as good as hobby grade RX’s have ever been, but SDR operation is not for everyone. Some people do not want to be tied to a computer or an operating system that might not be usable in 15 years. Speaking of computers, they can be noise sources. Some users do have to track down and eliminate noise sources, including sometimes hard to isolate computer noise. I am fortunate, this has not been a real issue for me, I have had to do very little, almost nothing, to deal with it, but I have seen people frustrated by it.
T!