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Quad Fm3 question

The Captain said:
Hi chaps,

update after testing the quad against my Arcam tuner. Like Tony I only intend to listen to R3. Not even Classic FM.

Actually the Arcam sounds a little -more- distorted than the Quad. But essentially the same, IE to me it seems/ feels like a reception issue. I will try shifting the Omni aerial back a bit in loft tmrw. Really my only option.

One thing I do notice though. The Arcam has a mono button, unlike the quad. Pressing this, the sound quality improves markedly. Almost perfect in fact. So I'll scoot back & read the replies- IIRC someone asked what the FM3 was like with the mono button engaged (another reply reminding them that alas it has no mono button).

Thanks, Capt
Click to expand...

Stereo FM is MUCH more demanding than mono. Inherently it has more distortion and noise, particularly a rise in distortion for loud HF components. Problem of it squeeing a quart into a pint pot. Having a tuner with a wider, flatter IF helps a bit. But then can make the tuner more prone to adjacent/alternate channel signals causing problems. That's what some of the 'super tuners' like the old Yamaha CT-7000 have selectable IF widths.

If you want to avoid that you need to go to the ipayer 320k aac output. Chances are that is a better representation of what R3 send out for distribution. But will still have level compression during the day that is more noticable than for evening concerts.
 
Jim Audiomisc said:
Having a tuner with a wider, flatter IF helps a bit. But then can make the tuner more prone to adjacent/alternate channel signals causing problems. That's what some of the 'super tuners' like the old Yamaha CT-7000 have selectable IF widths.
Click to expand...
Interesting, as my Akai has that; wasn't sure why but now I know. I've tried both aerial inputs but haven't followed it up with any analyses. I just leave it on whatever works/sounds best. I get full deflection on the LEDs regardless of station etc.
 
I guess the other thing to point out is there are situations of very high signal strength but also reflections, side-band or whatever it is called etc. I’ve certainly had situations in places I’ve lived where the strongest R3 on the dial wasn’t the cleanest, and this may possibly be what Captain is hearing (though I’d bet on tired electrolytic capacitors first). I’m lucky here I can totally peg the meter on my Sony 5150 on R3 with one of those naff plastic ‘T’ ariels one pins to the wall. Best reception I’ve ever had.
 
@Tony L I'll have a peep inside today see if any caps obviously n/g.

But wouldn't my Arcam tuner distorting similarly, & when it's mono switched on the reception distortion clearing up.. signify simply I'm in too poor an area to successfully p/u a good stereo R3 reception, with my aerial, in the loft? I think I've formed this conclusion.. unless I'm mistaken.

I just need to rule out anything I can affect. If I have & can only get a good mono signal.. it's a wasted venture unfortunately, as A) the quad doesn't have a mono switch & B ) I wouldn't be satisfied listening to a compromised mono output, from such a good stereo tuner- I'd always be dissapointed. Stereo signal for R3 is imperative to me.

Not a total waste: the Arcam is useable, in mono for R3. But I do think I'd rarely use it like so tbh.

Thanks, Capt
 
Yes, if the Arcam does the same it has to be a reception thing. Try moving the aerial if possible.
 
I suspect unfortunately that while FM3 & FM4 tuners are undoubtedly works of art, Iplayer on 320 is likely better quality.

If someone was really, really clever they could use the pot and box of an FM4 and the original display, with a raspberry pi, and make it look and feel exactly like an FM tuner but actually be finding the high bitrate stream..

🤔

😂

Not me though.
 
Tony L said:
I guess the other thing to point out is there are situations of very high signal strength but also reflections, side-band or whatever it is called etc. I’ve certainly had situations in places I’ve lived where the strongest R3 on the dial wasn’t the cleanest, and this may possibly be what Captain is hearing (though I’d bet on tired electrolytic capacitors first). I’m lucky here I can totally peg the meter on my Sony 5150 on R3 with one of those naff plastic ‘T’ ariels one pins to the wall. Best reception I’ve ever had.
Click to expand...

TBH This is where having an RF spectrum analyser can come in handy. Lets you see how crowded/powerful the band may be.

Decades ago when only the BBC used FM, life was easier for FM tuners as it meant that in most places they could ensure low levels in adjacent and alternate channels. But ye olde FM pirates and then the commerciallisation of FM radio ran a coach and horses though that. Now more like the USA.

If you have strong alternate/adjacent channles then you need a narrow IF to minimise sound quality damage from them. But you then get the higher distortion of a narrow IF!

Probably also poorer SNR because the gain has probably been wound down by sensing the power levels. You can see some spectra illustrating this dilemma on my webpages.

The problem stems from FM theory. You need an infinite bandwidth to perfectly carry even a simple audio sinewave. Fortunately, the distortion is generally low enough not to be noticable *given decent reception conditions and a good tuner.*
 
Tony L said:
but also reflections, side-band or whatever it is called
Click to expand...
Multipath? The only time I had this was in '72 or 3 with an upmarket Pioneer. At least I assumed it was multipath, partly because of birdies and warbles and partly, I think, because the tuner had a multipath filter which worked but not necessarily with better s.q.
 
All FM radios are affected by multipath - interference between direct and reflected signals causes AM modulation, which gets through the FM detector. Vintage tuners were fussier about this.
The only cure is a more directional antenna - why my Sony ST-S361 has a switched input attenuator to cope with the overload that this antenna might cause as a side effect.
 
davidsrsb said:
The only cure is a more directional antenna
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Which, if with sufficient elements, can capture signal over a much greater distance. An omni in the loft is not, i.m.o., going to cut the mustard in rural Wales. Depends entirely on proximity to TX, output from said TX (which should be adequate anyway), fairly clear line of sight and directionality and capture ratio of the antenna incl. its location height.
 
@The Captain

Download this PDF - Ofcom's own mapping of FM signal strength, Wales and look at page 3 to check your location - it'll give a feel for whether fitting a 'better ' / highly-directional aerial even can help.
 
Fill your boots, via this page and sim searches on the Ofcom site..:
www.ofcom.org.uk

Coverage

Radio Operations Coverage; Ofcom licenses all UK commercial television and radio services. Our Broadcasting Code also sets out the rules which television and radio broadcasters must follow.
www.ofcom.org.uk www.ofcom.org.uk
 
martin clark said:
@The Captain

Download this PDF - Ofcom's own mapping of FM signal strength, Wales and look at page 3 to check your location - it'll give a feel for whether fitting a 'better ' / highly-directional aerial even can help.
Click to expand...

Hiya Martin, very kind to post this detailed map.

The one mid wales, on the coast, is definitely mine at only 9m away (Blyflythfth or something).

But even being so close, I can't get a good signal. I know there's a hill in my village, bang in between me & the mast. Quite a high hill. But I assumed that bc it's so close, & also a whopper of a mast (160m & 4 red aircraft warning lights up it).. with a 'proper' aerial as I've bought, I'd be good. But it seems almost certainly, not so.

Naiivity, & idiocy have collided here it seems: I forgot I even had the Arcam tuner! Ideally I'd have tested for signal strength before buying the Quad. Even if that meant a wasted £18 on an aerial.

Thanks, Capt
 
Mike Reed said:
Not a fortune and could be useful elsewhere. A proper multi-element array, mast, coax and fitting would set you back at least 10 times that.
Click to expand...

I don't have TV, so won't be much use I don't think: R3 via the Arcam tuner in mono? It doesn't do the system any justice for me, not up to par tbh.

I'm just glad I didn't go for the 1/2 wave dipole, as that may well have been £40 wasted once plugs & cable on. It also may have meant a more directional 'link' to my mast.. but how on earth am I meant to determine this prior to trying it?

The moral of the story, I guess, is that Wales with it's valleys is at best a 50% gamble as to receiving decent FM signal, however close you are to your local transmitter.

Capt
 
last thing to try, if you have a mains extension lead, is to take the quad & wahtever else you need , like headphones up into teh loft, and 'swing' the aerial direction looking for strongest-signal / best -stereo...
 
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