Tuesday, May 15, 2012


I have been greatly enjoying my Kenwood L-1000T.  On Thursday night I gave it a serious listen, and was blown away, listening in intense sessions until 6am.  It has transparent, sweet, beautiful, dynamic, punchy, musical sound, but also silence from noise.  No apparent information loss from dynamic limiting as with Sony XDR-F1HD.  Completely transparent from top to bottom, unlike Pioneer F-26 which seems a bit veiled at the very top.  Bass solid down to subsonic frequencies.  Nothing unpleasant about the sound at all, and I heard some of the most convincing cello I'd ever heard from any source component.

On Friday night, I continued listening, but discovered that it only sounded right either at a loud level, or a very soft one, with intermediate levels just sounding wrong.  I suspected that my unit did not have deemphasis for US standard of 75uS, but rather for European standard of 50uS.  On Saturday I removed the Kenwood from my system and put the Pioneer F-26 back online.  I was shocked at how much noisier it sounded, I had always thought the Pioneer was one of my most quiet tuners.

Taking the Kenwood apart, I confirmed it had the 0.0082uF capacitor, as required for Europe, and not the 0.012uF capacitor called for in USA.  This tuner is even more beautiful on the inside than the case with dark metal and cast sides.  The main circuit board shown above is large and appears to be made of high quality material and packed with parts, organized in sections.

The RF stage is in a large metal box on the right side, from initial appearances it looks as massive as the RF capacitors on earlier Kenwood high end models like KT-917.  Of course this one only uses varactors and isn't nearly as good, but the rest of this tuner is far far better, making up for somewhat pedestrian RF stage.  Though small the RF stage does use a good single amplifier in a well thought-out design.

Along the left side is a large power transformer, a power supply feature two large and prominently "Audio" labeled power capacitors, and a second switching power supply for the computerized electronics.

I decided it would not be easy either to solder on an additional cap, or remove and replace the cap (though that would be somewhat easier). I am thinking I will get an equipment modifier to make that and other changes for me.  You can see the two brown colored mylar capacitors in the close-up photo below.  All the parts on the circuit board have leads that penetrate holes the board, and are soldered on bottom.  I have dealt with such printed circuit boards before, but I generally find it tough when the parts are packed closely together, as they are on this board.  Boards with surface mount components are worse.  I like modifying point-to-point equipment the best.

The bottom side of the tuner showed no additional capacitors soldered onto the bottom, as is sometimes done for quick modifications. 

Meanwhile, I figured out how to compensate for the european EQ.  I set up a parametric shelving filter in my Behringer DCX 2496 crossover.  Somehow this seemed to work best when I set the F to 2210Hz, with High Pass, but the amplitude set to -2.6dB.  That rolls off the highs above 2210Hz to a maximum of 2.6dB, reaching that maximum around 3180Hz (where the 50uS EQ kicks in).   I set the 2.6dB by ear then determined it would be correct for the frequency range from 2210Hz to 3180Hz, allowing for 6dB per octave slope.

The resulting sound was both superb and accurate.  A friend remarked it was both sweet and clear, my thoughts exactly.

I like having my top tuner play in the Living Room.  I can hear it pretty well in the rest of the house while I am doing things.  I often like background music, though perhaps even more often I like to have it off.  With a good tuner, I like to keep the music on more than with a lousy tuner, it seems.  But when I am playing background music with the L-1000T, it often draws me into the hot seat to hear it up close as well.

When I go into other rooms, but have FM playing in the living room, I obviously don't hear the stereo separation as well, though I hear much about the fundamental tone.  But often the reduced impact from lost separation is just the ticket to free my mind from the need to listen.  If I had the FM playing in each and every room, it might be too much, I'd want to turn it off more often, just to hear myself think.  I'm still working through these ideas.  I have so many tuners, the thought of having a tuner in every room appeals to me, then I could listen with full separation in every room, and also full local control.  But also simply to listen to background music from the living room tuner works mostly also.  I could also distribute music from the living room tuner to the rest of the house using Sonos, and use remote control in any room to change the station.

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