John Curl's Blowtorch preamplifier part II

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Perhaps FM isn't perfect, but neither is vinyl, Tape or digital. However they all benefit from attention and can sound quite good. The potential of the Sony tuner is great as a source if its output analog limitations can be overcome. The real disappointment is the lack of a digital output since the internal processing is all digital. Figuring that out would open a raft of possibilities. Per Brian's measurements Sony XDR-F1HD the deemphasis isn't right somewhere. That is a common problem. (All of the FM transmitter chips are preset to 50 uS for Europe and there are real market limits on them in that market, BUT the US (75 uS) products are all shipped set to 50 uS.) Get the basics right and then address the subtleties.
 
BUT the US (75 uS) products are all shipped set to 50 uS.) Get the basics right and then address the subtleties.
both my UK manufactured FM receivers (Sugden & Quad) came with the switchable de-emphasis set to 50us. Both can be switched to 75us for those transmissions that need it.

Here in the UK we convert the analogue signal to companded 14bit that gets transmitted around the country to be converted back to analogue at the transmitter. Quality is superb when the sound engineers want it to be.
 
I've got a problem with the whole dang thing.

In the point or context that: signal itself is a pure plasma function and upon encountering any solid, the signal ends up with a complex LCR function, within the moment it undergoes delta. Which in finality stresses the obviousness of gyroscopic/toroidal (a dual in/out in balance) nature of both signal plasma and 'matter' itself.

Half of what we hear in these electrical systems hinges on these aspects.
 
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signal itself is a pure plasma function and upon encountering any solid, the signal ends up with a complex LCR function, within the moment it undergoes delta. Which in finality stresses the obviousness of gyroscopic/toroidal (a dual in/out in balance) nature of both signal plasma and 'matter' itself.

However, an eleven dimensional theory of supergravity, which is supersymmetry combined with gravity. The eleven-dimensional spacetime was to be compactified on a small 7-dimensional sphere, for example, leaving four spacetime dimensions visible to observers at large distances.

I think you undercompactified your understanding, duality relations between superstring theories relate very different theories, equate large distance with small distance, and exchange strong coupling with weak coupling. So there must be some duality relation that can explain how a superstring theory that requires ten spacetime dimensions for quantum consistency can really be a theory in eleven spacetime dimensions after all.

So what you are hearing really is your past in the sense that it co-constitutes your experiences. However, to say that one is only one's past would be to ignore a large part of reality (the present and the future) while saying that one's past is only what one was in a way that would entirely detach it from them now.

However I prefer to deal with the here and now reality I exist in and the above goes nowhere. Lets get back to improving the experiences we have access to, rather than an imagined, better than reality, universe we will forever be frustrated by.
 
Even if one wishes to specifically remain solely in the engineering aspect, then some perfunctory acceptance and knowledge of the point mentioned is what can carry one forward into producing 'better sounding' equipment.

Some form of acknowledgment of the point is critical to high end. Every time one looks a component and how it integrates with the whole (finished item) or the function of the component itself, this issue is raised.

There are as many differing communications and misunderstandings as there are people to integrate.

The point is germaine to the subject of the thread, as not all taking part in it are at the simplistic point of realization that one resistor may sound different to another.

The base considerations of the 'why' are critical, with respect to moving to other stages.

Insofar as mentioning it further, I agree that beyond the basic point, it gets very muddy for most people, and the discussion is best to be an internal and individual effort -after the basic orientation as to the origins of the issue are realized.
 
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Sony did have to back off of the original "100 KHz" analog bandwidth for SACD - too much DSD high frequency noise was breaking thru the output filter (the "shaped noise" is > -60 dB fs, ie ~ 10-bit resolution at 100 KHz)

now consumer DSD output is 50 KHz analog low pass filtered - when not just ran in to a "DSD compatable" pcm audio dac chip
 
Sony did have to back off of the original "100 KHz" analog bandwidth for SACD - too much DSD high frequency noise was breaking thru the output filter (the "shaped noise" is > -60 dB fs, ie ~ 10-bit resolution at 100 KHz)

now consumer DSD output is 50 KHz analog low pass filtered - when not just ran in to a "DSD compatable" pcm audio dac chip

SONY may have chickened out, but we are made of sterner stuff. Our SONY SACD Upgrades fit a completely new filter/buffer audio output module, with 18dB/oct filtering at 98kHz. We have done well over 500 such Upgradeas around the world, with only ever one complaint that it blew up an amp - although the amp's designer (Marsh) said: "Don't be worried, it runs very close to the edge, it sounds better that way, and they blow up all the time!"

And 98kHz sounds way more alive than 50kHz.

Regards, Allen
 
SONY may have chickened out, but we are made of sterner stuff. Our SONY SACD Upgrades fit a completely new filter/buffer audio output module, with 18dB/oct filtering at 98kHz. We have done well over 500 such Upgradeas around the world, with only ever one complaint that it blew up an amp - although the amp's designer (Marsh) said: "Don't be worried, it runs very close to the edge, it sounds better that way, and they blow up all the time!"

And 98kHz sounds way more alive than 50kHz.

Regards, Allen

One more complaint from me. Spam from you!!!!
 
I have my DSD master recorders rebuilt with steep filters in the mid 90KHz region.....and also my Marantz SA-7 Mk II, that I use for consumer SACD playback. There is no problem with garbage above that frequency now.

Even 50KHz, gentle slope filtered DSD sounds better than super high bit rate PCM....In addition to my DSD equipment, I also own very good 192/24 DAW AD-DA studio DAW equipment , and have on one occasion heard a demo of DXD-PCM stuff at 384/24.....the only reason to go there at all is for editing ease, not for musical quality. DSD when well executed can sound virtually the same as the live mic preamp feed....not even 384 sounds like that. If you don't own the gear and don't do live recording, you can never know this truth from direct experience. I agree with Allen Wright about higher F, steeper filters for SACD.....it works in reality to the ear and does not supersonically drive following equipment into slewing issues. No consumer on earth has 384 KHz/24 bit media yet, and it is still quite rare in studio DAWs, only from Pyramix at this time I believe. Consumer 192/24 is now out there, but even in studio form, it is still sonically short of consumer SACD sound quality....BETTER than CD, yes, but still not as good as decently done SACD crippled with 50KHz filters.

Reality check....we have Billions of musically interesting CDs in the world....all under sampled at too low a time rate and amplitude resolution....the real challenge is...what can be done to push the up-conversion even farther than is done today to make this huge body of existing works more listenable?

Also, this FM thread is both FUN and important too....there is still a lot of good programing on FM...Might as well make the listening experience as good as is reasonably achievable! I DON'T like using up precious tube life in my 10B for casual listening, and my "daily driver" Grunding Fine Arts FM tuner has its limits.......I can see one of these digital Sonys coming my way soon, along with power supply and output stage replacement. Sounds like a fun project.
 
Reality check....we have Billions of musically interesting CDs in the world....all under sampled at too low a time rate and amplitude resolution....the real challenge is...what can be done to push the up-conversion even farther than is done today to make this huge body of existing works more listenable?

Working very, very very hard on that clock to get it to a point where it's jitter bandwidth correction or accuracy approaches the 0Hz point. Just my experience. I have some very interesting things I've done with clocks in various pieces of gear and it is actually quite amazing the level of sensitivity that the human system has to jitter and how close it has to approach zero before issues go away, according to perception.

Clock trumps oversample/upconversion, in my experience.
 
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