Line Stage Update: one more Aikido available

Sorry, this unit is now also sold and gone. See my final update article posted Feb.6th 2017.

 

by Steve Graham
The N-F-P has gone to a new home.  Harri S. of Milton, Ontario had the high bid and is the proud (I hope) owner of the over-achieving line stage whose build I detailed.  I was a little sad to see it go, but Harri’s full purchase price went to the Georgian Bay General Hospital in Midland, Ontario, for the capital equipment renewal program.

The picture above?  That’s the prototype, also built around an Aikido 12Vac board and I am making it available for sale as well.  At the start of the line stage project, I had hoped to have two for sale.  The board from Asia was a non-starter, so to keep to my original intent of offering two units, I’m letting the Aikido prototype go, too.  As with the first one, the full sale price will be donated to GBGH.

The N-F-P detailed in my four part WoS article was kept as simple as possible so it could be easily duplicated.  I couldn’t resist colouring outside the lines a little on the prototype, the features of which are as follows:

–      Tubecad.com Aikido 12Vac board
–      The power transformer is more, well, powerful
–      The input selector switch has a Tubecad board attached for easier connection
–      The Freq. Tilt control is a subtle passive tone control from Tubecad (http://glass-ware.stores.yahoo.net/tilt2control.html)
–      Custom stainless steel “knobs”
–      Progressive power switch; filaments first (F position) then B+ once the filaments are warm
–      The filament and B+ control resistors normally mounted on the 12Vac board have been moved to a small auxiliary board.  This helps keep heat away from the board mounted capacitors
–      Auricap output capacitors from my stash of NOS parts.
–      Tesla input and JJ output tubes, my favourite not-outrageously priced tubes that actually sound very good, see my 6DJ8 shootout: (http://wallofsound.ca/audioreviews/vacuum-tube-shootout-6dj8-types-part-1/)
–      The same good quality Alps volume pot as the first N-F-P
–      LED hidden by the power switch in the off position turns red in the filament (F) position then orange when switched to the B+ position.

The sound is essentially the same as the first N-F-P, but perhaps a bit more incisive.  This is to say good, even before you consider the reasonable price.  There are about 100 hours on the prototype.  I expect with time its sound will improve a bit more.  The 3 position tilt control has a subtle, but noticeable effect.  When the tilt “knob” is horizontal the response is flat; there is 2db of attenuation, but the 12Vac board has plenty of gain.  When the knob is turned clockwise the bass is boosted by 1db and the treble is cut by 1db.  Rotating the knob counter-clockwise has the opposite effect.  If a recording is slightly tizzy in the treble, the tilt control can compensate a bit.  If a track is a bit too bass heavy this can be tamed as well.

  nfp-2-int

 

Anyway, here’s the deal: The first person to email me at nfplinestage@gmail.com can have the prototype, for $450 Cdn funds.  I’ll include shipping to any Canadian address in the $450.  Please no low ball offers.  As with the first N-F-P, the money is going to charity and the buyer will get a tax receipt from GBGH.  If you were to duplicate the prototype, it would cost over $700 to build.

Thanks for your support.

 

nfp-2

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3 Comments on Line Stage Update: one more Aikido available

  1. Is this still available? I can’t seem to get onto the gmail…thanks Jan

  2. Wesley A Smith // 2017/03/05 at 2:31 pm // Reply

    I got mine up and running. I’m using a 12v wall wart and the sound is amazing. Just one question what tubes are paired in the gain section and which ones in the output section.

  3. Steve Graham // 2017/03/07 at 4:58 pm // Reply

    Hi Wesley,
    I’m glad you’re enjoying the Aikido. I found the sound best (when using the blended Tesla/JJ combo) if when the Teslas were in the input position (V1 and V2) and the JJs in the output (V3 and V4). One thing to watch for especially when using a blended tube set is that the filament voltage doesn’t get too high. I wouldn’t let it get higher than 24 volts max. because tubes from one mfr. might be dropping more voltage with a resultant shortened life.

    Good luck with your project, Steve

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