John Curl's Blowtorch preamplifier part II

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There was nothing like listening to KPPC back in the day with Dr. Dimento, now that was an interesting experience with alternative music to what everyone else was playing. Those were the days.

Thank you George for all that information. I will have to read that and figure out how to do what you are showing on the 75 ohm co-ax cable coming from the cable company. Right now I need to figure out what is making my computer screen bounce, coming and going, I think after one of Microstupids critical updates? Now to figure out which ones to roll back. It is only happening while in my browser so very annoying when it starts up.
 
Its a good read isn't it :) Interesting how it says FM back then was pretty much the best source available with regard to dynamic range etc.

I am not surprised! I used to listen to Proms live from the Albert Hall while living in London in sight of Alexander Palace.

Now softened by the mist of nostalgia, I (think I) remember the almost zero noise level being a hundred feet below the timpani and brass!
 
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I did, and I didn't use the internal speaker. It was not night and day even with NPR, IMHO obviously.

That’s good to show that the most important item on a Low-Fi set is the speaker :D

Tecsun, Sangean, Kaito, Eton, Degen, ect. (PLL with DSP implemented IF or totally sw radio architecture) are marvels of performance at a ridiculous price for such reception quality, stability, flexibility.
A portable radio with such a chip http://home.comcast.net/~phils_radio_designs/Si4734_Hardware.pdf
can be had for $40-$50 (my New Year’s present)

Steven and all of you USA residents and FM lovers, check out this site:
Zip Code Signal

George
 
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Look at what Tidal offers: https://tidalhifi.com/us At $10/month for 44.1 lossless FLAC and a large library that's growing, there is not much reason to own music anymore.

There is another service Deezer, Deezer is coming soon! that promises the same.

There will be dedicated player boxes that support this and sound really good soon. I know of one with SPDIF out and up to 192 KHz that will be all of $129 when its released. This is the competition for traditional FM radio.

However if you need the added coloration, distortion, wow and flutter of vinyl, that version is a ways off.
 
As I said before, different tuners have different design approaches, even if they are in the same price range.
The Marantz 10 series, I would presume, was designed for maximum fidelity when the FM station would broadcast it. I suspect the Mac tuner was optimized for difficult conditions. Both are OK approaches.
However, I must admit that Richard Sequerra and I are both 'fossils' when it comes to today's program presentation. The old analog transmissions, once done with vacuum tubes everywhere in the chain, really did sound good. Today, about the best you can get is a CD quality sound from FM transmission. Good, but not as good as all analog (in my opinion).
I never had gotten complete audio satisfaction from the digital transmissions used today. Perhaps, I was spoiled in the '60's, but for the last 45 years, when I first heard my first 'quality' digital attempt, I have never found complete satisfaction in either IC's or digital based transmissions.
However, that is my problem, apparently not one that people here generally have. This may be a fundamental reason why we disagree so often here.
My local community FM station is an all analog transmission path....good quality Denon CD players, large diaphram condenser mic, analog mixing desk, analog processor/stereo encoder, analog link transmitter, analog link receiver, analog transmitter amplifier.

This community format gives opportunity for local amateur announcers to deliver relaxed two hour programmes featuring their special interest music genre....most of these air time slots are on Sundays.

The processing is mostly AGC, with very little 3 band compression.
The sonic result is delightful, cd music playback sound is hifi and the on-air mic is perfectly revealing of announcers' vocal characteristics.

No vacuum tubes anywhere, but the result is perfectly listenable and enjoyable, unlike the way over processed commercial channels.
IOW, good FM sound is still available.

Dan.
 
Demian, thanks for the allert to Tidal. Unfortunately, out in the provinces it might take a while longer. This is the message you get if you want to register from the Netherlands:

TIDAL is already in the US, Canada and UK. Join our mailing list, and we will let you know when Tidal becomes available in your country.

Bummer, because I would sign up right now. The highest bitrate webcast I know of is Linn with 320 kbs MP3, which is probably good enough in most cases. However, their musical taste does not accord with mine, so I am stuck with 128 kbs or less.

Anybody knows hq web radio?
 
You can always use a proxy server (Google for 'public proxy server') to simulate living in the US or UK. See also Open proxy - Wikipedia, the free encyclopedia

Demian, thanks for the allert to Tidal. Unfortunately, out in the provinces it might take a while longer. This is the message you get if you want to register from the Netherlands:

TIDAL is already in the US, Canada and UK. Join our mailing list, and we will let you know when Tidal becomes available in your country.

Bummer, because I would sign up right now. The highest bitrate webcast I know of is Linn with 320 kbs MP3, which is probably good enough in most cases. However, their musical taste does not accord with mine, so I am stuck with 128 kbs or less.

Anybody knows hq web radio?
 
In Europe its called Wimp. Not a good name to start a business in the US. You already have it I suspect.

For now I'll stick with web streaming via my ROKU. I can listen to college radio from Boston, LA, San Francisco, and our member hhoyt's stream from North Carolina all in the same night. The range of music from old folk to extreme avant guard simply is not covered by any service.
 
Manna From Heaven...

It is local council verge bulk rubbish collection in my local area this week.
On my way to work I glimpsed a corner of what could be a mixing desk buried under other stuff.
And indeed it was...WTF !, an Allen & Heath GL2200 32 channel mixing desk.
allen-heath-gl2200-32-219570.jpg .
GL2200-SERVICE-MANUAL.pdf
GL2200-USER-GUIDE.pdf
Both pdf's are very well wothwhile studying.

This desk ran an internal SMPS board (missing), with an external PSU input socket on the rear panel.
This socket is provision to power the desk from an external A&H linear supply box, and power down the internal SMPS.

The manual specs supply of +16V 1.5A, -16V 1.5A.

Any suggestions of suitable supply schematic please....I have lost track of the recent supply discussions, and I am not sure that those are of sufficient current capability.

Dan.
 
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