Digital Radio Reception Observations

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Kelly
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Digital Radio Reception Observations

Post by Kelly » Fri Dec 16, 2011 9:36 am

I recently replaced the not-so-great GM radio in my Pontiac Solstice with one of the new JVC double DIN KX-something-or-annother model with GPS, Bluetooth(tm) and HD Radio. The JVC is very nice, but I was a little disapointed with the amount of processing many of the music stations here in the Washington DC area are using on their digital streams. Now granted I realize that the processor manufacturers have created one-box for analog and digital solutions including delay, but the downside is the digital stream is adjusted to sound like the over-processed-old school way of thinking that processes analog audio for loudness. So we take the potential for a increase in fidelity with the digital stream and trash it with a bunch of multiband compression and clipping? Really?? I know it would be more work, but to me why wouldn't you run separate processing chains, linking them together only for delay syncing? In a world where radio is competing with streaming and IPods, why programmers still feel distorting the audio to be "loud" just confounds me. These programmers and engineers who still live in the 70's as it applies to their station sound need to wake up. Okay rant over on that..

One thing that blew me away was when making my 40 mile drive down I-95 South home the other evening, my radio locked in digital mode on WCBS 880Khz out of NYC and stayed locked for about 20 miles of the drive! I hadn't set up my presets on the AM side yet and was doing a scan. My radio stopped on WCBS 880Khz and displayed the calls on the screen. About two seconds later the "HD" light stopped flashing and the quality improved as it locked onto the stream. Pretty impressive!
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Dale H. Cook
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Re: Digital Radio Reception Observations

Post by Dale H. Cook » Fri Dec 16, 2011 9:45 am

Kelly wrote:why wouldn't you run separate processing chains
Because the difference would be very noticable when the radio flips back and forth between analog and HD in areas of poor reception.

My NPR station is in HD, and thanks to the non-agressive processing it is difficult to hear any difference between their analog and HD when the receiver flips - what I notice most is a bit of hiss when the receiver is in analog mode, and that is because the signal strength is a bit low at those times.
Dale H. Cook, Contract Engineer, Roanoke/Lynchburg, VA
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BroadcastDoc
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Re: Digital Radio Reception Observations

Post by BroadcastDoc » Fri Dec 16, 2011 11:43 am

What Dale said! ;)

We originally used separate chains and processed the HD differently. While it sounded awesome, listeners in our outlying areas complained, since it was pretty jarring when the audio rolled back and forth from analog to digital.

We clean it up a little, but try to keep the loudness the same for that reason.
Christopher "Doc" Tarr CSRE, DRB, AMD, CBNE
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Dale H. Cook
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Re: Digital Radio Reception Observations

Post by Dale H. Cook » Fri Dec 16, 2011 12:16 pm

BroadcastDoc wrote:We clean it up a little, but try to keep the loudness the same for that reason.
I had hoped that the advent of FM HD would lead to less aggressive processing on the HD1 to take advantage of the format. with stations backing down their analog processing to match the HD1, but in my market the HD1s are processed as heavily as the analogs on the commercial stations. None of the three commercial FMs that I work with have HD yet, so I have not had the chance to try to implement my hope. If we do get HD I will probably be able to set up the processing the way that I want to as management likes the way I handle processing. BTW, two of those stations have 8100A/XT, but the one that people say sounded the best with music was the one running a Cutting Edge Unity 2000 with my custom preset. Unfortunately that station is now sports talk. This coming year I need to push to move the Unity to the one remaining music format of the three.
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BroadcastDoc
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Re: Digital Radio Reception Observations

Post by BroadcastDoc » Fri Dec 16, 2011 1:22 pm

Yeah, I had hoped so as well, but it didn't (and heaven knows I won't be allowed to be the first one to try!).
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Deep Thought
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Re: Digital Radio Reception Observations

Post by Deep Thought » Fri Dec 16, 2011 11:23 pm

BroadcastDoc wrote:Yeah, I had hoped so as well, but it didn't (and heaven knows I won't be allowed to be the first one to try!).
Well....it's hard to justify processing to the 0.1% of listeners who have a "HD" radio and cause 99.9% to receive an inferior product. As much as I would love to back off processing on every station I work at, reality dictates that the "old school" high-density AM processing prevail to have a fighting chance against EMI.

Was at WXYG in Sauk Rapids again this week to do some tweaking and continue to be surprised what we have been able to achieve there with that little 250 watter being processed with a Vorsis VP-8. I'm not hitting it that hard and the audio sounds great even though this is a fairly challenged low-freq (540 KHz) station and narrowband antenna. It'd be fun to try IBOC with this processor.
Last edited by Deep Thought on Fri Dec 16, 2011 11:52 pm, edited 1 time in total.
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eadler
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Re: Digital Radio Reception Observations

Post by eadler » Fri Dec 16, 2011 11:28 pm

If it makes you feel better, my HD2 is less aggressively processed than its FM counterpart. Mind you, my HD1 and primary (FM) audio on the HD transmitters isn't processed nearly as much, but that's classical...
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