[ClefChef]

Some gear has come my way that forces the sale of my "personal" Aikido preamp. This preamp is a result of extensive listening tests, sourcing of various (and rare) audiophile components.

Power supply: after trying various regulated HV power supplies, including Janus, shunt regulated, CCS, I decided to use choke filtered power supply as it is presents the lowest DCR power source, and that translates in excellent micro dynamics and level of detail of the sound. Oversized low DCR dual primary transformer capable of 250V @ 200 ma and 6.3V @ 5A was used. CLCRC filter is composed of Nichicon 47uf C1, 10H 100ma Hammond choke, Nichicon 150uf C2, TDK CM2 power resistor (ultra low noise), and final 4.7uf film cap.

6N1P and 6N6P tube pairs were selected for their excellent linearity, low noise, and low output impedance (6N6P). The tubes are biased for higher current to achieve lowest distortion and highest linearity. Operating points (plate voltage, current) were selected after extensive testing and audition.

AC tube heaters, referenced at 1/4 B+

Kiwame precision carbon film resistors used in tube cathodes for their excellent tonal quality, Allen Bradley carbon comp non-inductive resistors used as grid stoppers, precision Dale resistors were used in the rest of the circuitry.

Coupling capacitors are Auricaps (had them saved just for this special project).

For volume control I used 128-step relay attenuator, thus eliminating major source of volume pot noise.

RCA connectors are CNC copper, very high quality, signal wiring - silver plated teflon cable.

Preamp has two pairs of RCA inputs and one pair of outputs.

This preamp is absolutely the best I've heard so far. It easily outperforms Don Allen, George Wright, Bottlehead, Conrad Johnson preamps it was compared with. Absolutely incredible level of transparency and detail. Preamp is very quiet - no noise, hum or hiss - absolutely "black" background.

Unfortunately I have overspent myself and now must choose between several preamps that I wish I could keep (and I wish I could keep them all!). My asking price is $950 shipped in CONUS. Price includes matching pair of 6N1P tubes and a pair of carbon plate 6N6P (yes, there are different 6N6P's).

[MaxCast]

I see your previous post is marked sold.  To avoid confusion, is this preamp for sale or sold?

[ClefChef]

This one is available for sale. I built and sold several Aikido preamps.

[thomashek]

Could you tell which preamp models, yours bested ? Why in your opinion it was better ?
Thanks

[ClefChef]

Compared to WLA-12 custom (my own), Bottlehead III "upgraded version", Don Allen linestage (with dual volume controls), and briefly with Conrad Johnson (I believe PV-2 linestage). As three first mentioned are excellent preamps, they each had their respective "signatures" to the sound. Aikido seemed completely transparent as if it was not there. The feeling of transparency and openness - for lack of a better word - is the major trait of this preamp (and Aikido topology in general). There were differences at different tube operating points and with different power supplies, but this particular configuration with these particular tubes sounds the best. Aikido PS noise cancelling topology allows low DCR "unregulated" power supplies (read big transformers and big chokes) with less filtering with no added noise that results in added microdynamics and general "transparency".

[ClefChef]

bump.

[ClefChef]

SOLD.