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THE CGV-PRE1and CGV-PRE1p AUDIO PREAMPLIFIER
 
 
 







Now you can build this high quality tube preamplifier in a few short hours and listen to your favorite music source, or with the CGV-PRE1p, your favorite source and LPs with your favorite Moving Magnet Phono source. Frequency response is 5hz-100kHz with little NFB. Linearity and low distortion is assured by circuit design. The two stage cathode follower design lowers the distortion by feeding the signal from one nonlinear device into another linear device inverted. This means that the distortions added in the first triode are negated in the second. It is like taking whole plus numbers, adding minus numbers, and adding some of the plus numbers back. So if I put in 10, and the first triode adds -3, the second adds plus 2 for an overall 9. Instead of using negative feedback to accomplish this, it uses an "intrinsic" negative feedback. In other words, in this case two wrongs do make a right!

The Phono section is the ubiquitous passive design. Some may scoff at it claiming it not to be very dynamic, but I have used this design in both tube and solid state, and have listened to CD versions of the same LP and have found virtually no difference in sound quality and dynamic range. Phono section is designed for Moving Magnet cartridges as low as 3 mV output and 47K impedance.

Shown above is the CGV-Pre1P. The Line preamp has two less tubes on the end where the sheilded ones are. As you can see, it is small and sweet. The chassis is a 10"X6"X2" matte black (Oh, you see that for yourself!). I use the 6EU7 tube for highest quality sound with lowest hum.

Also, solid state rectification is used. This plus the fact that the tubes are biased at a nominal voltage/current, this amp will last a loooong time.

FEATURES:

Selectable input for the PRE1p
One dynamic unbalanced matching output. That is, it is a cathode follower and will match to both low and high impedance power amplifiers.
No global NFB.
Sheilded tube sockets for lowest hum in phono stage.
Point to point wiring with plenty of terminal strips for most physically stable construction.

SPECIFICATIONS:

Line stage frequency response - 20-50Khz, 5-100kHz -3db, 300mV input sensitivity
Phono stage - 20~30kHz, 3mV input sensitivity, 47K impedance.
Output impedance - 470ohm to 100K ohm

Price for CGV-Pre1:

KIT        $269
BUILT    $379

Price for CGV-Pre1p:

KIT        $349
BUILT    $449

Check, Money order, or Paypal accepted. Please allow 20 days for delivery. Email me for order.

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