The audio is cut at 15kHz with a very steep filter (100 dB/oct roll-off and 1000's of degree phase shifts) to avoid interference with the 19kHz pilot.
I once did DB listening tests on such a filter with a few guys; 3 out of 4 could reliably identify whether it was in the chain, and they preferred it with the filter in ...
Jan
The best stereo encoders like the Orban 8500 use a high-order 19 KHz notch coupled with a 20 KHz brickwall anti-aliasing filter, both implemented in the digital domain, not a LP filter. The result is 2 Hz to 15 KHz +/- 0.1 dB encode, 0.01% THD rising to 0.05% at 15 KHz, with 110 dB s/n, with 144 dB of processing dynamic range. There is significant encoding of 15-16 KHz signal. On my Kenwood 600T in full quieting I can measure >80 dB S/N from my station with the board potted down. Of course I hear little above 15 KHz at this point in life....
Either way, I consider the sound quality of WXYC-FM very high fidelity. All bets are off once a station adds HD subcarriers to it's signal which I have steadfastly refused to consider. These noise sidebands often raise the noise floor in many FM tuners, and the sound quality of the HD is often inferior to the main linear FM carrier, having been compressed, phase scrambled for symmetry and in a tragic final attack on quality, psychoacoustically data reduced.
The only reason for HD Radio is to allow station owners to have multiple channels and extract more revenue. Analog FM offers a gradual stereo-to-mono transition in weak signal areas, HD offers a full mute in these situations, so I guess it is quieter!
My $0.02 worth...
Howie
Hi Scott, I hear you. I have mixed feelings about this and perhaps my unease has led to misconceptions as to where I stand. I also have a similar unease when we have audiophiles who turn into instant reviewers and can make major pronouncements in nanoseconds, that cause me to turn (so as they not see my face) and roll my eyes, where it is clear that often "brand bias" or some elitist name thinking has influenced them. So I see both sides of the coin.
Sometimes I just ignore them, mainly because I think that the 'defective' piece of equipment, where an instant flaw was detected, actually sounded like music to me. So go figure?
BTW, I did coin the "JLTi" acronym that the late Allen Wright also used, it stands for "Just Listen To it. This was definitely a shot at 'branding' mentality.
Used to be three fourths of FA (old UK slang...) FM signal around here -- but now with DAB, for all it's faults, we have in house signal and on the road coverage all through the mountains here... They co-located a bunch of DAB repeaters with cell sites; which would not have worked with FM. Mostly I listen to Radio 4 - speech - or 6 (digital only anyway) so there's no real loss vs quality FM. Sometimes you win...
My experience was with traditional analog FM. I realize that more performance can and has been squeezed from the format. Your numbers are very good.
Jan
TNT didn't say that as far as I can tell but of course "the people" seem to love their distortions how ever they appear.
It is in his signature so I injected it in the quote field. I just caught me at the right time to hit my funny bone.
There was a time when a decent FM tuner receiving BBC Radio 3 was an essential part of most British hi-fi systems. I cannot comment on Belgian radio, but I would be surprised if there was not an analogous station.Tournesol said:
You may have a bad tuner, or a bad antenna (causing multipath reception). Or maybe you just listen to a bad station - there are a lot of them these days.
No biggie, it's becoming more and more obvious that the cold analytical hardcore accurate (by conventional standards) electronics are not what folks want, more and more people are admitting to their preferences for a little of this or a little of that.
Yes, my Revox tuner used to sing when I lived in London in the early 70's. Live BBC concerts (esp. Proms) are well remembered (and recorded!) and I used to live by Angus McKenzie's revues.
His bio is worth a read: 2005 Obit
I do think, at least if you live in the right part of USA there is higher quality radio potential than in UK. I used to really enjoy WMFT when I lived in Chicago and the broadcast quality was never less than superb. Radio 3 in UK I had a love hate relationship with for years. Partly because i was always in a fringe area, but mainly because their live concerts were during what they referred to as 'drive time' and the optimod was set for in car listening. When Nicam simulcasts were available on TV I would listen to those as they were not compressed.
By the time I could afford a really nice tuner they were threatening to turn FM off, although I suspect they have given up on that now!
By the time I could afford a really nice tuner they were threatening to turn FM off, although I suspect they have given up on that now!
The SF Bay Area has quality listening potential on some FM stations, especially the NPR type (commercial free). Some stations actually have live music from their control rooms at times. The best commercial program has been 'The Prairie Home Companion for the last 20+ years or so. While it has a new name now, they weekly broadcast for 2 hours some very well recorded live singers (usually young women) who can show what a hi fi can do, as well as many acoustical instruments.
I have a tube Marantz 10 tuner for my best FM reception, but the Sony was purchased to sub for it when I was working on the tuner.
At first, the Sony tuner was pretty good in obvious ways, but on further listening, had a slightly edgy sound. I replaced the ceramic caps and the sound is less edgy. However, it still has a 'digital' sound residue that the Marantz does not have. I don't think that I can fix that.
In general, I listen to FM radio for many hours each day, but with no expectations of audio quality, as it is usually news and commentary. I normally just use a Comcast cable channel, rather than direct FM pickup, for convenience, and there is certainly an audio difference IF I chose either the Sony or the Marantz 10 for receiving the program. The Marantz 10 sounds wonderful, but only in mono, and I do not normally use it in stereo. It is a listening experiment, rather than improving with I normally have to put up with with Comcast, FM or Video playback that I play most of my waking hours.
I have tried a more recent Sequerra FM tuner, and it was more 'clear sounding' than the Marantz 10, but not that much more enjoyable, if at all.
I have a tube Marantz 10 tuner for my best FM reception, but the Sony was purchased to sub for it when I was working on the tuner.
At first, the Sony tuner was pretty good in obvious ways, but on further listening, had a slightly edgy sound. I replaced the ceramic caps and the sound is less edgy. However, it still has a 'digital' sound residue that the Marantz does not have. I don't think that I can fix that.
In general, I listen to FM radio for many hours each day, but with no expectations of audio quality, as it is usually news and commentary. I normally just use a Comcast cable channel, rather than direct FM pickup, for convenience, and there is certainly an audio difference IF I chose either the Sony or the Marantz 10 for receiving the program. The Marantz 10 sounds wonderful, but only in mono, and I do not normally use it in stereo. It is a listening experiment, rather than improving with I normally have to put up with with Comcast, FM or Video playback that I play most of my waking hours.
I have tried a more recent Sequerra FM tuner, and it was more 'clear sounding' than the Marantz 10, but not that much more enjoyable, if at all.
We have a fair number of NPR stations and a couple of independents. WGBH and its affiliates broadcast high quality music program fairly continuously and live studio broadcasts as well as pops concerts can be very good. Most of the rest of commercial radio here is pretty bad.
I have HD radio (Harman Kardon Logic 7 surround system) in the car which I find surprisingly acceptable most of the time, certainly not as bad as it's made out to be for casual listening.
For home use I have an ancient 5 gang Kenwood KT-8005 and a heavily modified 4 gang McIntosh MR71. I live in a difficult reception area and the 8005's RF performance is about the best I have ever seen so that's mostly what I use. (It was designed by the guys who founded Accuphase just before they left Kenwood) It's a very cool tuner and sounds quite good.
I have HD radio (Harman Kardon Logic 7 surround system) in the car which I find surprisingly acceptable most of the time, certainly not as bad as it's made out to be for casual listening.
For home use I have an ancient 5 gang Kenwood KT-8005 and a heavily modified 4 gang McIntosh MR71. I live in a difficult reception area and the 8005's RF performance is about the best I have ever seen so that's mostly what I use. (It was designed by the guys who founded Accuphase just before they left Kenwood) It's a very cool tuner and sounds quite good.
Look at JA's measurements of an unnamed (by me) amplifier in Stereophile's current edition. Maybe distortion mismanagement would be better.
Or may-be it is you that have a bad hifi system, not performant enough to make the difference with a good digital source ?
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It dawned on me a while ago that many on diyaudio seem to do favour solutions that to me must mean more distortion. So I just wanted to cheer them on a bit
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