Fiddling with software based tx audio

[2RT307]

I have been interested in SDR, as well as software based audio for some time. I recently purchased a Focusrite Solo to allow me to use my existing XLR mic into my Yaesu FTdx3000. (I have been running the W2IHY 8 band eq and EQ Plus for quite a while now). I couldn't seem to eliminate RFI with the Focusrite, so I bought a Rode NT-USB mic. The Solo came with some nice software, including noise gate, eq, compressor, and reverb. I am not using the reverb, just the gate, eq, and compressor withe the Rode mic. So far, I am getting good reports after MUCH fiddling around with eq settings. I don't know if this will replace my W2IHY gear at this point, but it has been an interesting new way to process my transmit audio.

73,
Brett

 

[2RT307]

Well, I guess I should have asked if anyone was running software based TX audio... I was hoping to get some feedback on what other folks are running, and if they have had success with it. If you have a "good enough" computer, there are tons of software VST's that you can use for free, along with VST hosts that are free. So, you can effectively have a high end "rack" of gear without spending a lot of money. Anybody? Bueller???

73,
Brett

 

[RatsoW8]

Brett,

Nice looking mic. I'd like to hear it on the air. As soon as I locate my W2IHY iBox I'm going to hook up my MXL 990 through a small Behringer mixer. I think the mixer should be fine for some audio adjustments until I can figure out the eq settings on the 1200.

Are you able to control audio settings via software? I'd like to be able to see my audio curve in a graphic display. It's so much easier to make adjustments visually. I've actually been getting great audio reports without asking from all the dx I've worked with the Heil GM4 on the narrow setting.

 

[2RT307]

Brett,

Nice looking mic. I'd like to hear it on the air. As soon as I locate my W2IHY iBox I'm going to hook up my MXL 990 through a small Behringer mixer. I think the mixer should be fine for some audio adjustments until I can figure out the eq settings on the 1200.

Are you able to control audio settings via software? I'd like to be able to see my audio curve in a graphic display. It's so much easier to make adjustments visually. I've actually been getting great audio reports without asking from all the dx I've worked with the Heil GM4 on the narrow setting.

Thanks! One of these days we should do a sched. That GM4 should be pretty punchy on the narrow setting, which is just right for DX.

Here are some sites I came across for audio settings:

This fella does his audio with an 8 band eq:


As does this guy:
http://www.dj7zz.de/?MY_Equipment

This guy has settings for the internal eq with no outboard audio equipment:
http://www.w3rjw.com/FT5000/AUDIOEQFT5000.htm

There is software available from Yaesu to display your eq, but I don't think you can use the program since you don't have the USB hookup. If you did, the Yaesu software does allow you to see your tx audio settings via a display for the 3 band parametric EQ when you hook it up to your computer. This is using the PCC-3000 remote software program that they have for download on their site. (Look under "files"". There is a button on the software "radio" labeled "prmtrc", that opens the parametric eq display. You may be able to run this via the RS232C serial port, but I'm not really sure! Might be worth looking into.

You can use your monitor feature with headphones on, and make changes as you like and hear them in real time. That's what I did to get started, but it always sounds different over the air than it does via the monitor. I use a pretty flat set of 'phones from AKG, model 271MKII so they don't add anything (or take away) any of the sound. They are closed back, and completely cover my big ears. Neat feature with these is that if you take them off, they turn off. Take one side off your ear, and it turns off. Same with the other side. No feedback through the monitor feature since they are closed back.

I'm not sure which Behrenger mixer you have, but most of them have a parametric style eq. I agree, you should be able to get pretty close to what you want with that, and then add (or take away) anything else.

73,
Brett

 

[StrangeBrew]

Brett,
.... Are you able to control audio settings via software? I'd like to be able to see my audio curve in a graphic display. ....

.... You can use your monitor feature with headphones on, and make changes as you like and hear them in real time. That's what I did to get started, but it always sounds different over the air than it does via the monitor. ....

Just an idea I've been kicking around for a while but have never tried, I would like your comments on it.

I have a TV dongle SDR I was playing with for a while and thought that the ability to record a chunk of RF bandwidth would be good for setting up a radio, I was thinking that a wire wrapped around your co-ax and hooked into the SDR's antenna connection would capture what the radio is putting out and the various graphical displays available with different SDR software would allow you to really pick your signal apart.

Any opinions?

 

[fourstringburn]

That's a nice Rode NT-USB mic! That should work fine with an SDR radio or any radio.

One thing to consider when using a lot of outboard processing, are you mostly using it for rag chewing or both for this and DXing?

A lot of audio I hear on the air with lots of processing has somewhat of a heavy sounding FM quality sound. This maybe fine for rag chewing with good band conditions. but the audio can be buried especially on 40 meters when your signal is running along side a high noise level where as a stock mic without any processing would probably cut through much better.

I run my audio using an expensive ribbon mic into a Yamaha MG 10 small format mixer that has 3 band EQ and built in compression which I use very subtle like. I use very little EQ, only a 3db bump on the 2.5 KHz mid-band from the board. The other 2 band EQ knobs are set flat in their 12 o'clock position.

Other than that, I use my radio's software control programs TX audio 17 band graphic EQ having a range from 300Hz to 5.1KHz which when used looks like an upside down smile gradually peaking between 2.4 KHz and 3KHz then gradually sloping down at 5.1 KHz. This keeps the audio within the pass-band of HF radios and makes the received audio clear and articulate for stations on the other end without sounding bassy or tinny. This is what works for me.

Here is a pic of my mic that I use for both my HF rig and home studio recording. The large format mixer shown is not used for my HF radio.

 

[2RT307]

Just an idea I've been kicking around for a while but have never tried, I would like your comments on it.

I have a TV dongle SDR I was playing with for a while and thought that the ability to record a chunk of RF bandwidth would be good for setting up a radio, I was thinking that a wire wrapped around your co-ax and hooked into the SDR's antenna connection would capture what the radio is putting out and the various graphical displays available with different SDR software would allow you to really pick your signal apart.

Any opinions?

Hmmmm... I'm not sure. The SDR is actually a receiver, and it is the software that provides the panadapter. You will need an upconverter to make a regular TV dongle work on HF. The one I have works on HF and VHF/UHF... http://zao.jp/radio/soft66ad/

I'm guessing you would actually just receive your signal as normal, but would have to attenuate it somehow. Hopefully there is someone that can point you in the right direction on this. But hey, it's not going to kill you to just try it, so why not hook it up and see?

Another option is to find someone locally that has an SDR rig and have them record you. I've seen this done with the Anan (and Flex) transceiver on Youtube. They can make an audio and video recording of what they are seeing on their end.

73,
Brett

 

[2RT307]

That's a nice Rode NT-USB mic! That should work fine with an SDR radio or any radio.

One thing to consider when using a lot of outboard processing, are you mostly using it for rag chewing or both for this and DXing?

A lot of audio I hear on the air with lots of processing has somewhat of a heavy sounding FM quality sound. This maybe fine for rag chewing with good band conditions. but the audio can be buried especially on 40 meters when your signal is running along side a high noise level where as a stock mic without any processing would probably cut through much better.

I run my audio using an expensive ribbon mic into a Yamaha MG 10 small format mixer that has 3 band EQ and built in compression which I use very subtle like. I use very little EQ, only a 3db bump on the 2.5 KHz mid-band from the board. The other 2 band EQ knobs are set flat in their 12 o'clock position.

Other than that, I use my radio's software control programs TX audio 17 band graphic EQ having a range from 300Hz to 5.1KHz which when used looks like an upside down smile gradually peaking between 2.4 KHz and 3KHz then gradually sloping down at 5.1 KHz. This keeps the audio within the pass-band of HF radios and makes the received audio clear and articulate for stations on the other end without sounding bassy or tinny. This is what works for me.

Here is a pic of my mic that I use for both my HF rig and home studio recording. The large format mixer shown is not used for my HF radio.

Very cool stuff... that mic is $weet! I just got the thing working, so I only have it set to rag chew. However, it's easy to change the bandwidth on the FTDX 3000, and for DX I usually drop it down to 2.8 or 2.4 kHz and that brings all the bass down anyway. On my W2IHY stuff, I crank the bass back on the EQ Plus, and narrow the tx bandwidth on the rig as well. That was the reason I commented on RatsoW8's Heil GM4 sounding good for DX... narrow transmit audio.

73,
Brett

 

[RatsoW8]

All good info. As I've said before we reach the point of diminishing returns pretty quick with tx audio running amateur radio gear. It's not designed for hi-fi audio and it's real easy to push an amateur rigs transmitter into distortion with rack gear it isn't designed to be used with.

However, you can make some nice tx audio and if we all wind up chatting on 40 one day I'll crack open the 4 khz tx bandwidth on the my FTDX-1200 and play audio...

I am starting to wonder how the Heil PR40 would sound on my radio.

 

[RatsoW8]

Thanks! One of these days we should do a sched. That GM4 should be pretty punchy on the narrow setting, which is just right for DX.

73,
Brett

We should. I'm on vacation for a couple more days if you want to try it on 20 or 40. 20 has been good to the south and hearing lots of 5's.

I've had and have been using the GM4 for about 13 years..Got it free when I bought a TS-2000.

 

[2RT307]

All good info. As I've said before we reach the point of diminishing returns pretty quick with tx audio running amateur radio gear. It's not designed for hi-fi audio and it's real easy to push an amateur rigs transmitter into distortion with rack gear it isn't designed to be used with.

However, you can make some nice tx audio and if we all wind up chatting on 40 one day I'll crack open the 4 khz tx bandwidth on the my FTDX-1200 and play audio...

I am starting to wonder how the Heil PR40 would sound on my radio.

You're right. I've heard (and had QSO's with) Kenwood hybrids just using a plain old MC-50 that sound pretty darned sweet. But, it's a part of the hobby that I enjoy tinkering with, and the fellas that I talk with regularly keep things to a decent level (they really don't ever run more than 3 kHz wide on 40 during the day). A couple of them have the SDR rigs and keep an eye on guys' signals to make sure they are clean. (The guy that helped me with my settings was running a Flex). I have played with the settings for the 4 kHz wide tx on mine, but it only shows to do 3.5 kHz via my friend's Flex, which honestly is more than plenty. And I have ran 2.9 kHz and nobody noticed the difference.

That Heil might be a good way to go, but is pretty pricey. I got the Rode for $169 bucks with the pop filter. I bought it not only for the USB function, but because it had a cardioid pattern vs. my analog XLR connected MXL R144 (inexpensive ribbon mic) that has a figure 8 pattern. My shack is in a shed, and I have a big air conditioner that blows pretty loud. The noise gate really helps to cut it out, but you can still hear it when I talk. It is not as bad with the Rode cardioid pattern mic.

73,
Brett

 

[2RT307]

We should. I'm on vacation for a couple more days if you want to try it on 20 or 40. 20 has been good to the south and hearing lots of 5's.

I've had and have been using the GM4 for about 13 years..Got it free when I bought a TS-2000.

I won't be home until tomorrow night from work, but should have time on Saturday. I'll shoot you a PM and see what we can put together.

And great deal on the GM4! I have a buddy that runs one on an old FT-747GX, and it sounds really nice.

73,
Brett

 

[StrangeBrew]

Hopefully there is someone that can point you in the right direction on this. But hey, it's not going to kill you to just try it, so why not hook it up and see?

I've got some ideas but radio is kind of on a back burner for me now, I mostly just threw the idea out there because I thought the graphical display it could give of the audio you're putting on the air might be of interest to RatsoW8, and maybe others would like to play around with it as well.

It seems to me as though SDR receivers have potential as station monitoring devices if you really want to see what your putting on the air.

Anyway thanks for the input.

 

[2RT307]

I've got some ideas but radio is kind of on a back burner for me now, I mostly just threw the idea out there because I thought others might be interested in playing around with it. It seems to me as though SDR receivers have potential as station monitoring devices if you really want to see what your putting on the air.

My FTDX 3000 has an IF out, as does my TS-830. I plan on hooking up the SDR to see what it does. I've read that it makes for a cheap panadapter, which would be fun to play with. Cable is on the way...

73,
Brett

 

[StrangeBrew]

looks like you quoted me while I was doing an edit, I gotta be quicker on the keyboard next time.

Anyway if the SDR does anything interesting be sure to let us know, until then I'm out before this turns into a threadjack.