TX EQ updates since 1.4.X ?

N7CXI

Have there been any updates to the behavior of the TX EQ since (roughly) V1.4.X ?

Once the EQ was moved into the DaVinci DSP I was not able to get the TX audio back to the same timbre it was prior to that move.  After a few months of fiddling with it, I decided it was time to move on, and did.

So... it's time for me to consider another HF rig, and I'm back asking questions. If the TX EQ is the same or substantially the same as in 1.4.X I'll thank you for the reply. If it's been modified/fixed in a substantial way I'll at least consider purchasing another Flex rig.

I'm just that guy - very fussy about TX audio. If it actually sounds like a stack of 6dB/octave 2nd-order filters again I'll consider it.

Thanks,
Jim N7CXI

Bill -VA3WTB

Best to try one if you can, audio is just an opinion, different taste. Some like it natural, some like it heavy on the bottom end and others like the mids and highs to shine more.

There are a few guys around with the 6000's that have audio to die for, so I know it can be what ever we want it to be.

KC2QMA_John

Jim I too like great TX audio and as a recording engineer I can tell you the 6000's have awesome TX & RX audio. If you are good with setting up the EQ and signal processing you can make these radios sound like anything from wide-band broadcast type audio to sharp DX type audio.

The great thing is that the built in EQ and DSP in SSDR make getting great audio fairly easy. If you want to go farther you can always add external audio processing like EQ, Compression, Downward/Expander and so on it all up to you.

But the simplest and best improvement you can make to you TX audio is to start with a quality mic.

John

Tim - W4TME

But the simplest and best improvement you can make to you TX audio is to start with a quality mic.

I'd like to expand on this statement a little bit.  This does not imply that you need a $500 mic to sound good.  If you are using the 6500 or 6700 with the balanced mic/line input, a standard, off the shelf dynamic vocal mic can achieve phenomenal results.  I have several mics at my disposal, from top of the line Heils to cost effective Chinese wide diaphragm condenser mics.  I did some extensive A/B testing and I keep coming back to my 30-year-old trusty Shure SM58 that I used in my rock-n-roll daze (I had to replace the internal windscreen to get the stale **** smell out of it).  You can get this mic for under $100.

One thing I am a BIG fan of is making sure that a majority of the input gain is done at the first stage of the audio input signal chain.  So for my FLEX-6700, I use a single-channel solid state microphone preamplifier (VTB-1) to provide line level gain into the radio and use very little mic gain in SmartSDR.  This configuration results in the highest mic audio SNR.  And I find that the 8-band EQ is more than sufficient to tailor the mic's frequency response to my voice characteristics.

N7CXI

It's possible it was the combination of the rig I had plus the new software, or who knows what - all I know is that the Q disappeared in the lower bands and the overall timbre was thin after the TX EQ change. The mics used were PR-781, RE20, and several different 1" condenser mics from my locker - all connected through a small mixer that provided the makeup gain for the dynamic mics and 48V power for the condensers - no EQ or other processing.

I claim no fame as a recording guy, but after 30+ years of audio and DSP design engineering I'm probably qualified to operate an EQ. :-)  Unfortunately, that EQ and that rig at that time weren't getting it done. The same mics and mixer worked just fine on a "brand X" SDR, at least up until last night. Sadly, that rig expired around 9PM PDT with a hardware fault after many thousands of hours of continuous operation.

I'm not here to troll or otherwise give Flex any grief and no 6000 rigs are available around here to try, at least that I'm aware of. I like the look-and-feel of the SmartSDR software, and the fact that the radio was engineered as a radio, not a stack of boards in a box.  Maybe I can find some off-air recordings from a current system somewhere.

Thanks,
Jim N7CXI

KC2QMA_John

Flex has a 30 day trial. http://cart.flexradio.com/

N7CXI

Thanks, John. I wasn't aware of that. That does take the risk out of it!

Jim N7CXI

KC2QMA_John

Yes Tim, We are so lucky these days because of all of the affordable mics available today. An SM58 is a good option and you are correct you don't need a $500 mic to have great audio, the only thing that might be important to some is you will want to look for a Cardioid or Hyper-cardioid type mic. With the tighter pickup pattern of a cardioid mic you are less likely to pick up unwanted noises in your shack.

Tim - W4TME

Yes, the pattern is important,  but the DEXP can improve the apparent SNR when adjusted properly.  One other thing to consider is the frequency response curve.  I like a mic that has a 3 dB rolloff in the 50 Hz range just so that if I need to add low bass for resonance, I have it available.  But usually my TX filters roll off @ 100 Hz for non-communication quality type audio.

Rick WN2C

Jim, I saw your question last night but was not sure exactly what you were asking. I have had my 6300 since 1.4.16 and when I turned it on to make my first contact with it using a Heil PR 781, I was was given many unsolicited audio reports. All were great audio or beautiful audio using the default ESSB PR 781 profile. You can't go wrong with the Flex with the try it for 30 days, if you don't like send it back policy. Since I have had the Flex I have set up some different mic profiles and it is easy to switch between them as needed. 

P.S.
Keep in mind when v2.0 comes out there will be an upgrade fee for v2.0. All upgrades following 2.0 (2.1x, 2.2x) will be free till we get to 3.0 

N7CXI

Thanks, Rick.

Since I was informed about the 30-day return policy, I've relaxed a bit. To get right down to tacks, though, the main reason I haven't punched the button yet is because I've gotten used to steerable diversity with the "brand X" radio and the cost of a 6700 is beyond what I can justify at this time. In fact, I don't even know if SmartSDR supports phase & magnitude "steering" for diversity noise cancellation with the 6700.  That shows how closely I've been paying attention. :-)

73,
Jim N7CXI

KC2QMA_John

With a cardioid mic because of it's inherent ability to reject background noise you are reducing room noise at the mic itself so you don't have to run the DEXP as hard witch gives you a more natural sound.
TX audio is very subjective sometimes what sounds good to one person sounds bad to another. But in general if you choose a mic with a broad frequency response (20Hz to 20K Hz) or close you should be able to EQ the mic for your voice. And speaking of voice everyone’s voice is different so there is no one perfect mic for everyone because if there were there would only be one mic that everyone would use.

Some mics are built for a specific purpose for example the Shure SM-58 was made for live vocals where a loud PA system blasts the vocals out into the room or from a floor monitor speaker so feedback rejection becomes very important and that’s why most vocal mics you see on stages are Cardioid type mic’s. This is so that the mic only pics up the sound from the front not from the sides or back of the mic. One thing about SM58 style mics is they do require you to talk close to the mic to get a good present sound.

Now in broadcasting the requirements are a little different. An on air announcer needs a mic with broad frequency response and needs to allow the announcer to move a bit more freely around the mic without the problems associated with Proximity effect. The EV RE20,27 & 320 are very good at this because of the Variable-D technology with these mic's. If you have ever wonder why those mic’s are so long and what all those ribs along the side of the mic are that’s Variable-D technology.

Condenser mic’s are another animal they can give you the most natural sound but comes with some compromises. Condenser mics even cardioid types tend to have a wider pickup area then Dynamic mics and are fairly forgiving with how close to the mic you are but are more likely to pickup shack noise and because they have active electronics in the mic they are more prone to RF problems.

BTW I have heard a $29 RadioShack mic sound great on the air so it just a matter of finding the right mic for your voice so you may have to try a few mic's before you find the best mic for you.

Rick WN2C

Wouldn't the phase and magnitude steering be done with a steerable array antenna system, something like a 4 square? I know the 6700 is out of my price range too but I wish I had bought the 6500 over the 6300. I believe I could do alot more with it.

N7CXI

It can be, but then that's the magic of two identical, coherent receivers. you insert a fractional-N delay, (change the relative phase angle) or increase/decrease the magnitude of one or the other of the streams, then add or subtract one stream from the other. 

It sounds complicated, and in practice it is indeed a little complicated, but it certainly beats relays and phasing lines, or "phase controller" boxes that adjust the phase difference but munge the load impedance. Being able to control the magnitude of each stream precisely also allows you to compensate for most physical differences in the antennas, and use random-length feedlines.

Hmm... You'd think I was a fan, or something. ;-)

73,
Jim N7CXI

Ken - NM9P

RE:  "Phase & Magnitude Steering"... are they doing it now?  No.  

Is the 6700 capable of it in the future when the software engineers put it on the "hot list?"  I would say "Yes!"  and probably better than anyone else due to the hardware capabilities of the 6700's internal components - SCA's, FPGA, etc.  They already did it on the Flex-5000 and the 6700 is much more capable.

Ken - NM9P

RE: Transmit Audio & Mics:

Whenever someone asks me "Is my audio good?"  I ask "Good for what?"

"Good" audio depends not only upon the personal preference of the listener, it also depends upon the purpose for which it is intended.

I hear lots of hams who have audio that is very nice for a S9+20 dB Rag Chew that would be totally unusable in a DX pileup or for weak signal operation on 6 or 160 Meters.  And I hear lots of stations whose audio is "fantastic" for a contest S&P station that I wouldn't want to listen to for more than 30 seconds in a rag chew.

This is the power and beauty of the Mic Profiles, including TX Bandwidth, TX EQ, PROC, and DEXP.  The user can customize multiple profiles to match each purpose.

By using these tools, the 6000 rigs (and even the 1500/3000/5000) can sound very nice with relatively inexpensive microphones.  Yes, I also have heard wonderful signals from a $29 Radio Shack Mic.  (They have a couple I wouldn't mind trying.)

I have also tried SM58 knock-offs and decided not to keep them.  With MY voice and operating style, I found that the '58's have too much proximity bass.  I tend to close-talk the mike, just barely touching the foam windscreen.  It is the way I keep my mic level constant.  Others, like Tim, swear by the SM58.  He sounds good with it, and it matches HIS voice and mic technique.  One-size-does-NOT-fit-all in the audio world.

Expensive or inexpensive, I prefer a mic with a wide response without too many "peaks and holes" in the frequency pattern.  A little rise in the articulate frequencies (800-3000) can be helpful to provide additional clarity, but the TX EQ is very versatile and can compensate for variations in response and allows tayloring the response for the intended purpose.

I have found that the biggest challenge with some "cheap" microphones is not the response bandwidth, but that some of them have very annoying resonances that cause sharp peaks or dips at particular frequencies that make them sound...well.... cheap.  Listening to a voice with a sharp, peaky response is very tiring on the ears - like listening to a singer using a poorly equalized sound system with that one note that is almost feeding back, but just drives a peg into your ear!

I have used an old classic Electrovoice EV-664 to good effect.  (I rescued three of them from a church PA cabinet when the Trustees were preparing to throw them in the trash!)

My current, mid-level Mic is a Heil PR22UT.  Its response is similar to the PR781 with a little less bass and a little less back-side rejection.  It is clear and articulate, but most of all, it matches MY voice.  It was on sale for only $106 (US) at Guitar Center. 

Would I get better audio from a $500-$900 Mic?  Perhaps.  Would it be worth the additional $400-$800?  Probably not for my voice and purposes.  I do more DXing and Contesting than Rag-Chewing and am already often greeted by my Rag-Chew bunch with "There's Ken and that wonderful audio."  If I need to fine-tune my signal for ESSB, I still have a lot of adjustments I can make with my TX EQ before I think about moving up to another Mic.

I have seen many $50-$125 Mics that would probably sound just as good.  There is one $29 mic at Radio Shack that I would love to try, just for fun.  It looks like a Sennheiser, but I don't know who makes it for them.  At at this point I don't want to spend any more money on mics.

If you want to see a demonstration of various Mic Profiles and their capabilities in the presence of noise, I have three tutorial videos on Youtube.  

www.youtube.com/nm9p

They aren't professional quality, and have a few tongue-twist errors, but they can give a relatively good idea of the possibilities and process of tayloring Mic Profiles.

Ken - NM9P

Ken - NM9P

I just reviewed this thread from over a year ago, right after the release of v.1.4

https://community.flexradio.com/flexradio/topics/eq-adjustment-with-1-4

What has surprised me is the evolution of my various Mic Profiles since the ones I reported after initial experimentation right after the release of v.1.4.  The more I learned, and the better ways I found to monitor and compare my audio, the better I was able to get it to sound.

I don't know if there have been any subtle changes in the TX EQ response, gain, "Q," or anything else since v.1.4, but I do know that my rig sounds even better than ever after getting to know it well and making a series of progressive adjustments.

Ken - NM9P