Bottlehead Reduction Phono Pre-amp

PRICE DROP!  $540 - no further price drops.

Bottlehead Reduction: (http://bottlehead.com/…)

6DJ8/6922/7308 tube based Phono Pre-Amp. One tube per channel.

Gain of approximately 36 dB at 1 kHz and is intended for use with phono cartridges of 2.5mV and higher output, with 5mV output being the design center. Higher than 5mV output is certainly fine, and one may also use lower output cartridges with a suitable step up device.

Input impedance is 47.5K ohms, input capacitance is 50pF.

Frequency response exhibits +/- 0.3dB RIAA curve accuracy.

The Reduction is designed to operate into line stages with 50K or higher input impedance through interconnects of 1M or shorter length.
At 4.5mV input THD is 0.12%, THD+noise is 0.6%

Integration Upgrade: (http://bottlehead.com/…)

Four Camille Cascode Constant Current Sources (C4S) replace the stock plate load resistors, dramatically increasing the load impedance for approximately 60dB better Power Supply Ripple Rejection (PSRR) and the extraction of the full gain available from the tubes (up from about 36dB to about 40dB).

The addition of a Zener shunt voltage regulator lowers the power supply impedance yielding a sense of increased extension of both bass and treble.

Upgrades BEYOND:
Power supply caps are all Nichicon PW and last two are tipped with film capacitors (one Solen 3.3uf, one ClarityCap PX 1 uf).
Added high speed Cree diode
Heater filter cap is Nichicon Fine Gold with ClarityCap PX 1uf.
All wiring not heater related is cotton wrapped PVC over copper.
Heater wiring is shielded Mogami W2534.
RCA input/output connectors are Vampire Wire CM1F/CB
Output and RIAA curve capacitors are Sonicap Gen I
Wirewound resistors replaced with Mills resistors

Tubes supplied will be two pair of PC88 tubes. These have 7v heaters instead of 6 but work just fine. Because they are "underfed" they will not last as long as if they were on 7v but take 20% off of 10000 hours....they'll last long enough for you to find what you like. One pair are Tesla yellow label, the other are Valvo military (have the hawk symbol on them). Valvo are in original boxes.

Selling as I’ve built the Eros tube Pre and no longer require this.