FM-Stereo-Tuner: Currently vs. Vintage Version - e.g. Accuphase T-1200 (DDS) vs. Sequerra Model No. 1

I was recently amazed when I discovered this 5-year-old (pretty new) FM tuner model T-1200 (T1200) from Accuphase: (good pictures)
It is astonishing to me that FM radio is to be switched off or has already been shut down in some countries (replace by DAB/DAB+)
Interesting to know for me is, what was the motivation on Accuphase to create such a top class FM tuner with DSP technology so as the difference in sound performance compare to old fashion top class device for FM stereo reception like e. g. this unit:

Sequerra Model No. 1
https://sb015eafc300824f1.jimconten... - FM-1 - FM Stereo Tuner (user's manual).pdf

or to similar top class vintage units like K&H FM2002 or Revox B760.


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I don't know anything about these specific tuners, but for car radios, the main advantage of digital IF processing is that you can apply more fancy weak signal processing tricks than with an analogue design. For example, phased-array techniques that automatically use the best weighted sum of the signals of two aerials to get rid of multipath interference. Variable IF bandwidths were already used in completely analogue designs. Of course FIR IF filters can have a better phase response than analogue IF filters, which presumably leads to less distortion. You can also make really nice FM demodulators digitally, but a product detector using a coaxial cable for conversion from frequency to phase difference as used in the Studer A726 also works very well (but is too large and too heavy for car radio).

The main disadvantage of digital IF is the interference that you get from all the digital circuitry, and that you somehow have to keep out of the tuned channel.
What M said ^^ + the ability to switch modes based on the signal quality automatically, and deliver the best sound quality possible, based on the signal available. The ability to make sharp cutoff narrow (<150 kHz ) low group delay filters is essential in many crowded markets. This is cake for DSP at audio frequencies. The added benefit is using an outboard DAC for the S/PDIF FM output.

Silicon L:abs was huge in developing low cost DSP based FM circuits, where the IF is filtered, then under sampled with a relatively slow A/D, then processed.
These are mostly for portable and car audio use, but specs are poor compared to the referenced tuners above, and most top line FM tuners after 1974.
The chip based DSP processing has limits, and the math precision used limits dynamic range, distortion, separation, etc.

Accuphase is one of the few to do this FM DSP in house, and do it right. No precision limits, with world class specs, and supposedly, sound too.

FM is very much alive in the USA, not really any current plans to ever go all digital. Analog FM, on both transmit and receive, is much cheaper.
NXP has some pretty good car radio chips with digital IF processing. Sensitivity, dynamic selectivity, IP3 and large signal handling are all very good. They normally use oversampled ADCs, sigma-delta ADCs in fact, so the analogue IF filtering is only meant to prevent aliasing. Channel filtering is done digitally.
Here is my "stack" Digital Accu T1000 and aligned analog Tandberg TPT3001a .
You can see which one is in use :). Accuphase is very good actually. I also played it with Abbas tube dac but I prefer 3001a for its vitality connected to old Naim amps. It's way better than Nat03 . Maybe Nat01 would stand a chance. Having said that I'm selling Tandberg since I can't afford to keep bought at the moment and it's almost impossible to find North American version of T1000 and I'm in a " gold" period of hifi . Tandbergs are fairly easily accessible just expensive to service. A top tuner. Both came from biggest collection of radios I saw. Probably all best FM tuners ever made. Sansuit TUX1 ,Squerra Ref.Marantz 10B
Top Burmester Restek FM3003 Wieschoff, and mamy many others. If I had money I'd buy top 10 of them. FM is the best audio format ever conceived..I can listen everyday, all day. Any other " perfect source" ? 2 hours max


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music soothes the savage beast
Joined 2004
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I am very fond of fm tuners. Had many including top of the line kenwood and technics. FM tuner is constantly on unless i listen to lp's or cd's. Since i discovered how quiet sony st-s555es is, i sold all. Now i have 5 sony 555es tuners one for each system. (I still keep one magnum dynalab for sentimental reasons)
I love FM radio, at the moment I'm listening with my old ReVox A76. Not only amplifiers are interesting, tuners are also really fascinating, even if you build them yourself. Unfortunately, the program in Germany has been eroding for decades, it's downright lacking in quality. In September, DAB is being pushed regularly. The compression is also extremely annoying. Live broadcasts from concert halls are still great. I love FM.

That's sad to hear. How strange, that America, facing internal threats from political idealogues, still has a vibrant Nation Public Radio, and other places that Americans might see as being more civic-minded, are stressed. It's a tough world, and we can only hope to pass it to our children's children half as well as we were given it.

All good fortune,
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