Pioneer TX-9500 II

Pioneer TX-9500 MkII (top)

I bought this Pioneer about 8 years ago, and it finally went up into my Kitchen audio system today.

It's a fine sounding tuner, in the 3rd upper rank at least.  It's considerably more musical sounding than the Kenwood 600T and all the other silver Kenwoods from the 1970's.  Everything sounds sweet and lively.  Noise seems separated from the musical image (sadly, the Kenwood 600T does not do this).  But the noise is not as low as with the 600T.  The 600T is at least as sensitive and selective, if not slightly moreso.

I'm ranking it sonically just below the Kenwood L-1000T, and then the Pioneer F-26, in the 3rd rank of tuners which includes the Sony 730ES, Sansui D-99AMX, Yamaha TX-1000, and Marantz 20B.  The Pioneer is better sounding than a lower set includes the all the 70's Kenwoods (600T, KT917, KT7500, KT8300) I have listened to and the Onkyo 9090 MkII.  And then, most strangely of all, not sounding as good as the others mentioned, at the bottom sonically of all the super tuners I have, the McIntosh MR78.  (MR78 is plain ok sounding, but many tuners like the Pioneer TX-9500 MkII have a wider bandwidth and even lower distortion detector and MPX that give more lifelike detail without more brightness--with the MR78 already has plenty of but it doesn't help the apparent relatively dead and boring sound.)

Compared with the Pioneer TX-9500 MkII, the Kenwood 600T sounds cold, sterile, flat, uninvolving, much too bright and steely (unless high filter activated), but also slightly quieter.  In short, the noise and some of the life have been sucked out of the music with the 600T, but not with the 9500 MkII.

But I should continue to refrain that the 600T is a fine sounding tuner anyway.  If you had never heard anything else, you'd think it was fine.  Low noise and distortion, high performance.  But then fire up the 9500 MkII, and everything comes alive in a way you wouldn't have thought possible.  

(MR 78 is like the 600T in these regards, but differently.  If all you ever listened to was MR 78, you'd think it was fine.  But while the 600T adds a certain fuzziness to the sound because it has a resolution-losing but very wideband detector, the MR 78 adds a slight hardness to the sound because it's just trying too hard with a not-quite-wide-enough-wideband detector.) 

The Pioneer Signal Strength meter actually tells you nothing about the signal strength.  But it's a pretty good measure of signal quality, sort of like the inverse of "Multipath".  When you get to the top of the meter, no matter how strong the signal actually is, you're getting sound about as good as it gets.  Most stations vary from 4.5 to 5.  It's even more difficult than most to use as a precise tuning meter, so a scope hookup is recommended.

The TX-9500 MkII uses a very linear and wideband FM detector proprietary to Pioneer (P.L.B.) that works on the principle of being a phase compensated delay line.  This may have been Pioneer's all time best detectors, also used in the F-26 and F-28, all made in the late 1970's, which was a golden age for Japanese hifi because of the exchange rate.  Later, in the 1980's, the Pioneer F-91,2,3 series in the 1980's got progressively worse in terms of noise and distortion, something David Rich lamented in a classic Audio Critic tuner review in 1990 (while admitting that he himself had an F-93 because on some very weak channel he liked, the fake stereo it did was the best sound he could get).

In the wide mode, there are no ceramic filters in the IF path, only tuned filters (I used to think that was crucial) and a SAW (Surface Acoustic Wave filter, computer designed whizbang technology which became available in the late 1970's).  Ceramic filters are inherently noisy and "acoustic," so having all or mostly tuned filters could provide a "purer" sound.  But tuners using all or mostly tuned filters include MR 78, Marantz 10B and 20B, Sumo Charlie*, Kenwood 600T and KT917 in wide mode, and all classic tube tuners, a mixed bag sonically, and many ceramic-filtered tuners sound fine.

(*Inspired by the Marantz 10B, James Bongiorno used all tuned filters in the Charlie, except just one wide tuned ceramic, because, as he once told me when I asked him about this, "You need something to kill the crap way out there."  Well that's similar to Pioneer using one SAW in the TX-9500 II wide mode, except that a SAW is more sophisticated than a wide ceramic.)

The Pioneer front end is basically the best design you can do with a 5 ganged air capacitor, and more gangs are sometimes wasted in other super tuner models.  Being based on ganged air capacitors (turned by the tuning knob) rather than varactors has advantages in front end dynamic range, which is why many classic tuners are so good without being anywhere near as "sophisticated" as later tuners.