Studio1 SDR Software Review
Multiple SDR Radios
As was mentioned earlier, Studio1 will allow the user to run multiple instances of the software. Each instance can be configured for a different SDR receiver that may be connected to your system. For example if you have a VHF/UHF SDR radio and separate HF SDR radio you run them simultaneously using Studio1. For example you could have the VHF/UHF SDR listening for activity on the local ham radio repeater while using the HF SDR radio to listen to 20Meter SSB broadcasts. Each SDR radio connected can have it’s own set of multiple VRXs, SP1s, SP2s, and RX Controls.How many external radios can you have? Well, thats going to depend on how much CPU power you have available and your ability to physically connect the radios. However, using a couple of SDRs connected shouldn’t pose much of a problem for most CPUs since Studio1 is fairly efficient when it comes to CPU usage.
This is an area that Studio1 stands heads and shoulders above the other software offerings. To be able to fully appreciate this, you must have a fairly decent audio chain attached to your computer. At HRS the main SDR lab testbed computer is equipped with a Focusrite Scarlet 2i2 connected to a pair of KRK Rockit 5 studio monitors for audio output. This gives the ability to more critically evaluate audio quality than typical PC speakers. If you are using cheap computer speakers or your laptop speakers, you are missing out on a large part of what SDR can offer. You might want to consider investing in a nicer set of computer speakers or at least a good set of headphones. With that being said, the Studio1 DSP engine is a stellar audio performer. The other SDR programs just sound kind of tinny in comparison. Listing to Studio1, you will notice one thing right away the low noise floor. You won’t hear much unnecessary hiss with this DSP engine.
Another standout in Studio1 is its FM Stereo decoder featuring a proprietary SNR (Stereo Noise Reduction) algorithm. The audio quality from the FM stereo decoder is superb! The audio from the FM Stereo Decoder is very comparable with studio grade FM monitors that some of you may have come across in the past. AM is not slouch either. Studio1 utilizes an AM “soft filter” that warms up the audio. The audio from the AM decoder is very reminiscent of a tube based amplifier and is very pleasant to listen to. Of course with all the filters and other adjustments you can make to the audio SSB and CW also sound excellent.
Since Studio1 uses a bit of different approach to using your SDR equipment, it does a require a little time to get familiar with. However, the learning curve is very small. If you have been using other SDR applications past, you should be able to get up and going pretty quickly. Studio1 offers maximum flexibility and new ways you might choose use your SDR gear, so be sure to read through the manual. The manual includes several important keyboard shortcuts that are useful in accessing certain functions of Studio1 as well as explanations of the various settings. Speaking of settings, unlike other SDR decoding programs, Studio1 allows advanced users to tweak various aspects of the Studio1 DSP engine to their hearts content. As mentioned earlier listening to HF AM/SSB broadcasts with Studio1 was a real pleasure. Also it was apparent the the AGC control was doing an outstanding job without adding any artifacts to the signal. Shortwave broadcast listeners will appreciate the Studio1 the highly adjustable Synchronous AM demodulator (SAM) using a single sideband or double sidebands. The SAM demodulator did a very good job to help mitigate fading when listening to Shortwave broadcasts. One of Studio1s’ more impressive features when compared to other SDR program offerings was it’s weak signal performance. Studio1 was able to handily improve the readability of weak signals compared to some of the other SDR software offerings. This was especially noticeable on weak FM stereo signals using the SNR function. Another area that was pretty impressive was with receiving CW signals when using the CWPK and CWAFC features. CW Dxers will find these features excellent for isolating weak CW signals in a busy or noisy band. Also, weak SSB signals could be made quite readable when employing such features as the adjustable filters, the four Notch Filters, Noise Reduction, the flexible AGC settings, and the Noise Blanker. Again, Studio1 is very tweakable allowing you to access some of the inner settings of these features to customize your receiving environment,
Needless to say is how well Studio1 works depends ultimately on the quality of the SDR hardware you are using. Given that, I decided to take a look at how well Studio1 worked with some of the “not so higher end” SDR radios. I took a look at the lowly $20 RTL2832U and came away highly impressed with what Studio1 could do with the RTL2832U DVB-T stick. I simply dropped this 3rd party ExtIO.dll into the Studio1 folder and was good to go. FM Stereo form the RTL2832U was superb. The audio quality was excellent and the stereo separation was quite impressive. The RDS feature also worked well. UHF / VHF public service frequencies also came through very nicely in Narrow FM mode. So if you own a high end SDR HF rig and Studio1 and you might want to consider adding a RTL2832U for FM Stereo and VHF / UHF reception.
I also tried out using the RTL2832U along with the Ham It Up converter for HF reception. Again Studio1 came through and allowed for a very enjoyable HF listening experience using this cheap combination. Of course the RTL2832U / Ham It Up HF converter performance can’t be compared to a high end HF SDR, but it works very well for the investment. Again, even if you already are using a high end HF SDR radio with Studio1, you might want to consider picking up the low cost (Less than $75) RTL2832U / Ham it Up combo as a second HF radio. The only slight problem we ran into was the ExtIO was not %100 compatible with Studio1 in that we couldn’t change the sample rate or select multiple RTLs through the ExtIO.dll. However the good news was that the sample rate was set by default at 2.4MHz giving a pretty wide bandwidth to work with, plus the all important RTL gain settings were workable. Hopefully, this will get sorted out at a future date by the Studio1 developer or the ExtIO.dll developer. However, it doesn’t prevent Studio1 from working perfectly well with a single RTL2832U dongle.