Yamaha C-1 Vfet preamplifier - fully restored

Available for sale is a rare Yamaha C-1 Vfet preamplifier that has been completely restored back to prime working condition. This is a chance to own a piece of audio history and one of the most unique
preamplifiers ever built, without the concerns of repair and need for maintenance for years to come.

The paint on the rear plate has some signs of
aging and some scratches, but otherwise the unit is in really good cosmetic
condition and in perfect working condition. Please judge cosmetics based on the
included photos and please ask for additional photos if needed.

C-1 is an incredibly unique preamplifier as it
is the only Vfet preamplifier ever built. 

Finding these statement pieces is generally
difficult. Finding one that is fully restored, it is nearly impossible. The
restoration is difficult and not many people work on them. This was my
realization when I started building my Vfet collection and that is why I am now
specialized in restoring my own Vfet units. The "Vfet sound" can be
quite addictive and I now have a large collection of Vfet units. I very rarely
take on the restoration of other people’s units, but occasionally I might sale
some of the duplicates in my collection, as it is the case with this beautiful
C-1.

 

Once rebuilt, the C-1 is a solid and fantastic
sounding performer. Yes it's many bells an whistles make it the antithesis of
wire-with-gain, but the many options could come in quite handy if you need to
tame a not so well prepared listening space, or a lacking source, all without
the need of a DSP or other fancy digital equalization. The many analog bells
and whistles can also be defeated for those who favor a straight through audio
signal path, and I can tell you that the line stage of C-1 is superb and exceedingly
difficult to mach.

 

As far as the restoration, this is not a
typical recap and Deoxit cleaning of the pots and switches.

Restoration summary below:

• Unit fully disassembled and
  cleaned throughout


• All PCBs old glue and flux
  cleaned; new flus cleaned after soldering the replacement components


• All switches and pots, fully disassembled,
  cleaned, re-lubed, individually bench tested. 


• All ill-fated transistors
  replaced


• All components with tarnished
  legs replaced


• All electrolytic capacitors
  replaced with function appropriate replacements (i.e. audio caps for the
  audio boards, long life, high temp rated caps for the PSU, etc..)


• Any original board-scorching
  power resistors, replaced and lifted off the boards


• ALL service bulletins
  implemented. 


• Removed the factory power cord
  and installed a power plug to expend the choices for a power cord.


• Unit bench tested and fully
  adjusted to factory specifications


• Unit tested (all functions) for
  over 2-weeks in my personal listening space

All in all, a few hundred components replaced,
all factory service bulletins implemented, and any potential points of failure
mitigated. This C-1 is now bullet proof and has a new lease in life, without
the need of maintenance for many years to come.

Specifications

Frequency response:
5Hz to 100kHz

Total harmonic
distortion: 0.02%

Input sensitivity: 2mV
(mic), 2mV (MM), 150mV (line) ( NO MC option with C-1)

Signal to noise ratio:
60dB (mic), 70dB (MM), 90dB (line)

Output: 150mV (line),
0.775V (Pre out), 7.75V (Pre out Max)

Semiconductors: 110 x
FET, 143 x transistors, 2 x zener diodes, 58 x diodes, 4 x IC, 6 x LED

Dimensions: 18 inches
x 16 inches x 6 inches

Weight: 38 pounds

Year: 1976

 

This unit was originally sold in Japan and the
rear panel shows 100v, but it is now internally converted to 117v (factory
transformer primaries allow for 100v-117v conversion). I will ensure a sticker
with the proper voltage will be appended before shipping the unit out.

 

Only the unit and a generic power cord are
included in the sale.

 

CONUS shipping is included. International
buyers would have to cover the full international shipping cost.

Local pickup is encouraged, and an audition /
demo is available for your convenience if you come to pick-up in person.

 

 

Best,

Peter