Audio mixing, multiple receiver sources, advice requested

[majoco]

Detented controls are not a problem, depending on how coarse the detents are of course, 2 or 3dB per click but no more and it's easy to reset to a previously found setting - and they don't get inadvertently knocked off setting. I'm just pleased that it doesn't have sliders on a horizontal panel - just asking for trouble.

 

[Ubbe]

Remember that there are also software mixers for Windows or Mac. You can run it on a spare laptop if you don't want all the audio in your work computer. You have to get one of those small $5 USB soundcards for each scanner and also ground loop isolators, one will handle two scanners.

I'm looking at Reaper that has mute and solo buttons and FX features like compressors to even out the sound levels. It's a test period and after that it's a $60 purchase. It's probably loads of others as well, perhaps even free or shareware.

/Ubbe

 

[morfis]

Ubbe - I had thought about using something like an NUC (I have a couple that were aquired very cheaply from a company that made 'photobooths') with multiple UUSB soundcards but didn't know anything about software. Reaper looks interesting and though it will do far more than I want the price isn't prohibitive.

 

[majoco]

I have two Uniden UBCT8's that didn't have line outputs so I added them. The hard part was finding the correct pin on the small PC board attached to the volume control - note that I made the connection to the input of the volume control, not the wiper, so that the level was fairly constant. A single unscreened wire connected from there to a 10uF capacitor hanging off the centre of a phono socket on the rear panel and it all sounds good through an external amp and speaker(s).

 

[DeepBlue]

Most of the pro, semi pro and amateur "studio" mixers have way too much going on for what I would like. A simple black 1RU cabinet that has inputs on the back and switches on the front to add or subtract sources, an output control and maybe in the back or even under the hood a small pot that you could fine tune the various input levels. It doesn't need massive transformers on the front of each channel. We are talking amateur communications here not Pentagon approved military or high grade studio commercial gear. Most of us are already listening to signals from a 2-3" poly or paper speaker not aimed at us or even equalized in any way so a mismatch isn't going to bother me any in my radio room. If it had jumper selectable input levels that would be cool.

If you are worried about padding the inputs correctly, places like TecNec and Markertec (Same place) Sweetwater, Guitar Center, etc all have pads you can buy, or you can look them up online and build them yourselves easily. These aren't 2kw RF tuning circuit components, they are for audio levels and SMD components should be fine.

By the way, if you really want the confusing "solo" function, Mackie boards have that as well as most others at this point. That little blinking solo light confuses more amateur studio recordists than anything else.

Sean
Ex television studio engineer (NBC/GE OnO)
34th market, 16 years

 

[mbrennan376]

I am brand new to scanning, just received my first scanner yesterday. I have integrated it with my home office setup. I have a Yamaha MG124cx which is an entry level Yamaha mixer.

The inputs are:
1) Sm57 microphone For voice-over, recording, etc
4) uniden BCD536HP
5/6) digital OTA TV tuner
7/8) roku running through hdmi- analog converter
9/10) work laptop running through lexicon alpha USB audio interface
11/12 personal laptop running through lexicon alpha audio interface

So I have room for more scanners if needed.

I like having faders as opposed to knobs because it is easy to quickly grab the faders and pull them all down when I jump on a zoom meeting or get a phone call

I plugged the uniden directly into 1/4 line input using a mini - 1/4 cable from the external speaker output. It works perfectly for me.

I don't disagree with others about possibly needing iso transformers or pads inline between the mixer and scanner, but I didn't need any. I do freelance audio professionally, mostly for TV sports, and it is common to plug ipods or phones directly into mixers like this and we don't have issues. Maybe if you have multiple scanners you might end up with ground loops in which case an iso transformer and/or pin 1 lift can be purchased and put inline, I commonly use isoblox in these cases when I mix for work on older analog rigs that have not had a good power distribution thought out, or we are interfacing with 3rd parties. If your mixer only has a mic level input as opposed to mic and line level you may need a pad as DeepBlue mentioned.

 

[Ubbe]

By the way, if you really want the confusing "solo" function...

Shouldn't be confusing to any scannerist. Push the solo button to solo out one single scanner to listen to, and perhaps record, and mute all the rest. It's probably the most sought after function in a multi scanner listening enviroment.

/Ubbe

 

[belvdr]

lexicon alpha USB audio interface

I don't want to derail this thread too far, but if you have a moment, can you let me know if it's possible to use my mixer (Behringer 802USB) with my work laptop for Zoom calls as well (i.e. use a mic into the mixer for the laptop and the speakers I have as output)? I've thought a bit about doing this so I could use my existing setup with my normal work-from-home workflow.

 

[mbrennan376]

I don't want to derail this thread too far, but if you have a moment, can you let me know if it's possible to use my mixer (Behringer 802USB) with my work laptop for Zoom calls as well (i.e. use a mic into the mixer for the laptop and the speakers I have as output)? I've thought a bit about doing this so I could use my existing setup with my normal work-from-home workflow.

Yes This should work no problem. I spend 3-4 hours a day on zoom calls usually. You just have to set up the USB interface as the input/output device and route all the signals accordingly in the mixer and interface, taking care not to route your mic back to your output and vice versa. I have the capability of routing my conference calls to my interfaces as you have described. You can even do both at the same time. I used to take conference calls using my webcam mic and then used my wired IFB plugged into the headphone out of the mixer (Like the ones I set up for field announcers doing stand ups with stick microphones) to hear the call, so that the echo didn't get into my webcam mic and I didn't have to wear a headset on cam. But now I prefer the wireless USB headset pictured in front of my mixer as I don't turn on my cam much on zoom much anymore for meetings, just audio. It is a Logitech H820e. It is dect not Bluetooth so it reaches all over the house and I can even go out and weed my garden while sitting on a conference call. And it has a mute button and light on the microphone boom which is very helpful. I also have a jabra headset that I use for phone calls, but I don't take too many of those anymore.

 

[majoco]

That's why the Behringer RX1602 that I have ordered seems to satisfy all my requirements - 8 mono line inputs and 8 stereo (which I probably won't use) with switchable input level control on the rear panel, individual listen through, level, stereo balance and a mute button on the front panel for each channel, headphone with it's own level control, and the line outputs on the back with a master control on the front. Everything I want for listening to the receivers and nothing that I don't want such as mic inputs and tone controls. What I do want is for the courier driver to ring the front door bell......

 

[Ubbe]

Everything I want for listening to the receivers and nothing that I don't want such as mic inputs and tone controls.

I absolutly need british tone controls to get the best possible sound from each scanner model and also a bass cut button. Especially my Whistler TRX-2 seems to lack any kind of high pass filter in its audio and all subtones are at a terrible high and annoying level that needs to be attenuated.

/Ubbe

 

[majoco]

Yes, I know what you mean. I had an AOR AR2002 a few years ago that was very 'trebbly' that accentuated all the high frequency noises and made the voices sound very 'thin'. I fixed it by soldering a capacitor across the volume control and that was much better. I use a little 10 watt stereo amplifier with bass and treble controls driving a couple of small but good speakers and the overall sound has excellent intelligability but when it comes the DXing or a bit of CW I mostly put on a pair of headphones directly from the receiver.

 

[mbrennan376]

I have found the EQ controls on my mixer useful for the scanner as well. And they definitely help on some of my other sources

 

[majoco]

Well, it arrived late Thursday afternoon and I spent a happy Friday working out how it all worked and over a smoking soldering iron making up cables. It all seems to work very well, there's individual level controls on the inputs followed by a balance control. It took me a while to realise that the 'balanced' inputs work just fine with an unbalanced signal as long as I used an RTS (ring, tip and sleeve) jack plug with nothing connected to the ring. The 'mute' buttons (the red lights) are used as an input selector, then the now selected stereo signals are fed to the output bus via another couple of level controls and out to the little amplifier and speakers. Pics below with six receivers wired up although there's two more inputs to be connected from a bench PC and a laptop for a couple of SDR's. Below the mixer is a 8-channel multicoupler and a Debeg 7313 marine receiver - I intend making a wooden cased rack assembly for those - and all the other receivers are in that taller cabinet which was kludged from a large speaker cabinet - $5 from an op shop - the 2m rig is not connected into the system other than getting it's power from that homebrew power supply in the centre.