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FM tuner vs. CD sound quality?

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fr0g
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RE: FM tuner vs. CD sound quality?

shooter wrote:

It is worse by a considerable margin but interestingly the dynamic range is the same. The process of DAB strips the PCM (CD quality) signal back to MPEG 1 Layer 2, and its a complex one, after that its padded out with zero's to achieve a dynamic range of 71db.

So what your getting is a signal of 1537 padded out to 2048 which equates to 71db dynamic range which is the same as FM radio but FM is 2048 without the padding. PCM is 32768 giving us 96db.

All we need to do now is convert MPEG's 1537 into db's and we have the answer Smile

Not that the available dynamic range is relevant... I think you'd struggle to find a CD with a dynamic range more than around 20db, most are around 10 or less.

 

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shooter
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RE: FM tuner vs. CD sound quality?

fr0g wrote:

shooter wrote:

It is worse by a considerable margin but interestingly the dynamic range is the same. The process of DAB strips the PCM (CD quality) signal back to MPEG 1 Layer 2, and its a complex one, after that its padded out with zero's to achieve a dynamic range of 71db.

So what your getting is a signal of 1537 padded out to 2048 which equates to 71db dynamic range which is the same as FM radio but FM is 2048 without the padding. PCM is 32768 giving us 96db.

All we need to do now is convert MPEG's 1537 into db's and we have the answer Smile

Not that the available dynamic range is relevant... I think you'd struggle to find a CD with a dynamic range more than around 20db, most are around 10 or less.

 

 

I'm confused fr0g, I thought PMC which is 16 bit material has a dynamic range of 96db, with 24 bit being 144db and the like, basically 6db's per bit. The greater the db the greater the signal to noise ratio, SNR.

I though with lossy, you reduce the dynamics by 'squeezing' top and bottom of the audio band, which reduces the the dynamics thus reducing the db's, SNR and with it the bit rate.

DAB's MPEG 1 Layer 2 is worse quality the MP3. What i'm trying to work out is MPEG's 1532 samples per second and what that equates to in bit rate and [SNR], those figures then will translate into something my brain can understand, at the moment 1532 meens didldy squat apart from it worse than MP3...

fr0g
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RE: FM tuner vs. CD sound quality?

shooter wrote:

I'm confused fr0g,

 

Me too :) 

 

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shooter
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RE: FM tuner vs. CD sound quality?

fr0g wrote:

shooter wrote:

I'm confused fr0g,

 

Me too :) 

 

 

Laughing

 

Hopefully some fellow will be along soon who can shed some light.

Overdose
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RE: FM tuner vs. CD sound quality?

I think fr0g meant the dynamic range of the music and not the potential dynamic range of the format?

Or am I confused too?puzzled

excellent!

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fr0g
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RE: FM tuner vs. CD sound quality?

Overdose wrote:

I think fr0g meant the dynamic range of the music and not the potential dynamic range of the format?

Or am I confused too?puzzled

excellent!

You see, thisis where us with a little knowledge get mixed up.

CD has a potential dynamic range of 96db according to maths.

DAB, Vinyl and FM, less.

 

A good recording may be anywhere between 8 to 20 or so.

But I haven't a clue what that all means to SNR if anything.

And I am too tired and basically disinterested to look it up although if someone could explain, I'd probably read it. Head too full of Csharp today.

Smile

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shooter
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RE: FM tuner vs. CD sound quality?

fr0g wrote:

Overdose wrote:

I think fr0g meant the dynamic range of the music and not the potential dynamic range of the format?

Or am I confused too?puzzled

excellent!

You see, thisis where us with a little knowledge get mixed up.

CD has a potential dynamic range of 96db according to maths.

DAB, Vinyl and FM, less.

 

A good recording may be anywhere between 8 to 20 or so.

But I haven't a clue what that all means to SNR if anything.

And I am too tired and basically disinterested to look it up although if someone could explain, I'd probably read it. Head too full of Csharp today.

Smile

 

The true dynamic range of the cd instead of the dynamic range of the format? Yes i think your right here, it is less than the format, after all the process of recording is a compresion of the original live performance, if it wasn't then then you would never hear what is on a disc. I presume then that the actual process of compresion when recording does so to a point well below the format then as the same as DAB radio pads out in zero's to achieve the format dynamic range, in the case of CD's [PCM] 96db's.  puzzled

McRagefit
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RE: FM tuner vs. CD sound quality?

Just wanted to add my experience here Smile

I bought the PM/CD/ST 6003 combo about half a year ago and am very satisfied with the ST6003's sound quality. With a good broadcast (mainly the classical radio channel), it sounds almost the same as my CD6003!

dfa2124
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RE: FM tuner vs. CD sound quality?

I have a pretty humble hi-fi system myself but it is good enough for me to tell the difference with different tuners I have hooked up to it. For me, a recently-acquired Yamaha T-2 FM tuner has produced the most magical sounds I've ever heard from my set-up. There is a vibrancy and fullness to the sound that just sounds true-to-life. I have read that there is a lot of unit-to-unit variation on these tuners probably because of their age but after using mine for a while it definitely seems to be performing up to spec so I must have got a good one excellent!

Mind you some say that the T-2 is better than the highly-revered Yamaha CT-7000, and perhaps the good ones are.

zeppy
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RE: FM tuner vs. CD sound quality?

First of all, we need to separate two worlds, the analog and the digital.

I think, that the original question is about standard analog stereo (MPX) FM broadcasting, in the band from 88-108 Mhz, and the CD.

IMHO, using a high quality FM tuner , and, in the broadcaster side, thanks to the high performance (internal digital processing) MPX encoders (modulators) as the ORBAN OPTIMOD FM 8600, and transmitter drivers (this block converts the carrier+mpx=FM stereo), you can get a high grade of listening satisfaction, but, when you switch to CD, the difference in the high end is very noticeable. It's simple: FM top frequency is 15000-15500 Hz, according to the standard, and CD is 20000.

Again, there are two different worlds, digital and analog, and we need to keep this on mind at the time of make any judgements and reach a conclusion.

 

keeperofthekeys
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RE: FM tuner vs. CD sound quality?

i use a denon 260l tuner 30quid from cash converters..its very nice,  im not sure its a good comparison to cd? theres something about fm that seems to make the sound softer? more like a record or casette tape...i had my sky box going thru the hifi, compared radio three to fm radio three....waste of time to be honest,  there was no comparison...

MajorFubar
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RE: FM tuner vs. CD sound quality?

zeppy wrote:
 FM top frequency is 15000-15500 Hz, according to the standard, and CD is 20000.

FM may not sound quite as good as CD but that's not the main reason why, even those of us who don't have any hope in hell of hearing 15K+ can tell the difference Smile

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