Transmit audio raspy

  • 1
  • Question
  • Updated 4 years ago
Hi all,

I'm still new to my 6500 and trying to learn more and get things working the way I like. I'm having a problem getting my transmitted audio to sound good. I'm using a Heil Goldline mic, connected through the balanced input. I have mic+, mic- and ground connected on both ends. I was working with another Flex owner on the air and we made quite a few adjustments trying to get the audio just right. In the end, when he played my audio back to me the sounds was raspy. I don't know how else to describe it. It seemed to have good response across the spectrum, not really distorted...just raspy. I thought RF might be getting into my audio so I installed about 16" worth of 31 mix ferrites at my antenna feed point. As near as I can tell this had no affect on the audio.

So, I'm looking for ideas. I did notice the the Goldline has an impedance of 1000 ohms while the Flex is 600. I'm not sure this could cause the issue but I thought I would throw it out. I'm willing to spring for a new microphone if that will solve the issue, but I would like to be convinced it would help first.

Any and all help/comments appreciated.

Jon...kf2e
Photo of Jon - KF2E

Jon - KF2E

  • 588 Posts
  • 171 Reply Likes

Posted 4 years ago

  • 1
Photo of Greg

Greg

  • 656 Posts
  • 63 Reply Likes
I would be interested in reading replies to this. I have received crappy audio report using the balance input as well using a radiosport headset with a dynamic element and also using a computer type electret. Someone recorded it for me and I was completely embarassed. It was nothing like the audio in the MON circuit. It sounded torn and raspy like you say. I was not over driving and it sounds the same with low power or high.
Photo of Jon - KF2E

Jon - KF2E

  • 588 Posts
  • 171 Reply Likes
Just an update where I am with this...

I asked my question to Heil Sound and got the following reply from none other than Bob Heil himself.

"I believe your problem is that the Goldline is an unbalanced microphone and you are trying to use that into a balanced input of the Flex.  There is no better match than our PR 781 balanced microphone into the Flex. It is such a great match that Flex is now selling the PR 781. One  amazing microphone for amateur radio. It has a balanced output and you will discover a new world with that.  

Impedance is not an issue. It is an issue of balanced to unbalanced and this opens a HUGE door for RFI......HUGE."

I'm going to order a PR 781 and hopefully it will solve my issue.

Jon...kf2e

Photo of Bob G   W1GLV

Bob G W1GLV

  • 634 Posts
  • 107 Reply Likes
Jon, I use a PR-781 and always get good audio reports.
Photo of Ken - NM9P

Ken - NM9P, Elmer

  • 3825 Posts
  • 1164 Reply Likes
Jon....
I use a Heil PR-22UT which is also a balanced mike and get excellent reports, both when connected directly through the BAL port, and when going through a mixer and then into the BAL port.  

You might want to connect your Goldline mike to the Front panel before making any additional purchases.

BTW:  Just to make sure it is an RF infiltration problem and not overdrive/adjustment problems, run a quick check.... Turn RF power all the way down to 1.  Turn Monitor ON, listen to yourself in the monitor and see if there is any distortion.  Then listen in another receiver at very low power and see if there is distortion.  Then slowly turn the power up and see when it begins to distort.  If merely turning the power up reaches a point of distortion in an external receiver, that is a good clue that the problem is in the balanced/imbalanced input.
Photo of Greg

Greg

  • 656 Posts
  • 63 Reply Likes
I had a PR781 and I did get good reports from the bal input. But I wanted to use a headset (Radiosport RCS60F) that was shipped with the XLR cable. Reports on that were aweful even though the vendor said lots of people were using them on the 6000 series with good results. They sent me a front panel cable but have not been able to try that yet due to some antenna reconfigurations I am doing. This weekend I hope....
Photo of Don - kx9q

Don - kx9q

  • 376 Posts
  • 16 Reply Likes
Greg, I use a Heil Heritage mic going through the balanced input and get great reports.  I use a Radiosport like you but it plugs into the front jack.  When I talked to the people at Radiosport it was sort of like yes I could use the headset with the XLR cable but they also said they were coming out with a balanced desk mic for those who want to use the balanced input.  I got the impression that they did not think the headset would work as well as a balanced mic though they did not come out a say that.  
Photo of Reg

Reg

  • 120 Posts
  • 73 Reply Likes


Jon:

I'm using a PR781 with a FLEX-6700 and I have never had a bad audio report.  In fact, all audio reports are "excellent."  You're heading in the right direction by ordering the PR781.

Reg

Photo of Tim - W4TME

Tim - W4TME, Customer Experience Manager

  • 8699 Posts
  • 3268 Reply Likes
I am going to commit sales sacrilege here.  I have a lot of different balanced mics, from high-end dynamics and wide diaphragm condensers to very inexpensive dynamics.  All sound good on the FLEX-6000.  Each mic has it's own "color and personality", but the key thing is the frequency response curve.  For good fidelity you want one that goes down as low as 70 Hz and the upper end at least to 12k.  If you want to explore using a dynamic mic connected to the rear balanced input of the 6000 and not spend a lot of money, the Behringer Ultravoice XM1800S is a decent choice.

And before you start asking, the mic that gets the most use at my QTH is the Shure SM58.  This is a mic I have owned for 30 years and it still rocks (as it did in the mid-80s in live performances).
Photo of Jerry - W2TXB

Jerry - W2TXB

  • 82 Posts
  • 16 Reply Likes
When I first received the Flex 5000A, I had yet to receive the PR-781 that was ordered, so I connected my old Shure 585-SA to the radio via a matching transformer and adapter to the balanced input; even that mic (from the band days of ~1970) sounded good.

There are a lot of good mics out there, some are oldies which many would never expect to see in use today. :)
Photo of Ken - NM9P

Ken - NM9P, Elmer

  • 3825 Posts
  • 1164 Reply Likes
Before I got my PR22UT, I was using an old EV-664 (Silver Hammer) that I rescued from the trash bin when the church trustees were cleaning out the PA cabinet.  I actually got 3 of them in boxes, but only one connector, but I had another old one in my junk box.  It sounded pretty nice, once I got the EQ set up right.  But, boy, was it heavy on my boom stand!
Photo of Ken - NM9P

Ken - NM9P, Elmer

  • 3825 Posts
  • 1164 Reply Likes
Tim is correct.... Good mike selection is a function of matching your particular voice to the mike, and factoring in the purpose and the kind of sound you are looking for sound for. e.g. rag chew / DXing / Weak Signal work / all around hamming.  The best thing is to try one, and listen, listen, listen to yourself in a second receiver, preferably on tape because you can't really tell exactly what you sound like when live through headphones because bone conduction in your own head will color what you hear.   Then, no matter what mike you try, you will need to make a few adjustments on the TX EQ and listen to the recordings again.

You can get an indication if you expand the zoom on your panadapter and look at your pattern while talking to see if you are severely "peaky" or unbalanced.  Some hams are so unbalanced, with such excessive bass or treble, or have a huge peak or dip in the mid-range that they sound horrible.  Even worse, they are unintelligible unless they are VERY strong.  100 watts, nicely contoured, is often much more effective than 1000 watts of bad audio.

Although I use a Heil PR22UT, (The SM-58 has too much proximity bass effect for MY particular voice)  I have heard many good reports about this low/mid price mike at Radio Shack...
http://www.radioshack.com/product/index.jsp?productId=2997390&znt_campaign=Category_CMS&znt_...#
A super-cardiod dynamic with XLR balanced connector.
It is $35.99 regular price.

Sweetwater.com has the Behringer Ultravoice XM1800S in a 3-pack for $39.99 with free shipping and 2-year warranty!  Though I have not tried them, they would be worth a try.  You can split the cost with two friends, or have spares for other rigs...

They also have  Samson R-11 (SM-58 copy) in 3-pack for $69.99 and the lesser R-21 @ $49.99 for a three-pack.  My church bought 2 3-packs of the R-11 and I tried one (They only needed 5 and I thought I might buy one from them) but it also had too much proximity bass for my voice.  A couple of inches fluxuation in distance to the mike made MAJOR changes in the tone profile.  They would be great mikes if you don't like to close-talk them as I do.

I would have liked a PR-781 because of the increased side/rear rejection in the pattern, but it was more expensive than the PR22UT and this one sounds great.  If I ever get an amplifier, I may need the additional directivity of the PR-781 to cut down on fan noise.

The bottom line is take your time, compare several different mikes, and select the one that you can afford that makes your signal sound like YOU want it to sound.  This is part of the fun!