RENAISSANCE ONE-FORTY Mk.
IMPORTANT UPDATE PLEASE READ CAREFULLY Your Renaissance One-Forty has been fitted with a new thermal sensor circuit. It works in conjunction with the indicator lights located under the VAC logo on the front panel, and has two functions: 1) If the idle current in a pair of 300B output tube should drop well below acceptable limits, the light corresponding to that pair (left-most pair, left-center pair, right-center pair, right-most pair) will light green. At least one of these tubes should be replaced.
or generic 300B tubes. We recommend obtaining replacement tubes from VAC, stating that they are for use in the Renaissance One-Forty. CAUTION THESE UNITS CONTAIN NO USER SERVICEABLE PARTS. DO NOT REMOVE THE BOTTOM PLATES OR TOP COVERS. LETHAL VOLTAGES ARE PRESENT WITHIN THE CHASSIS. DO NOT OPERATE THE UNITS IF THEY ARE WET. VACUUM TUBES BECOME HOT ENOUGH TO CAUSE SERIOUS BURNS. NEVER TOUCH A TUBE WHEN THE UNIT IS ON. IT MAY TAKE SEVERAL MINUTES FOR THE TUBES TO COOL DOWN AFTER THE UNIT IS SWITCHED OFF.
INDEX Introduction Unpacking Installation Operation Installing New Output Tubes Replacement of Low Level Tubes Care Of Chassis Tips and Advice A Word About Tubes in General A Word About Output Tubes A Word About Low Level Tubes A Word About Impedance Matching A Word About Feedback A Word About Grounding Tuning Your System Specifications Footnotes Figures Warranty & Registration Form
INTRODUCTION The Renaissance One-Forty is a completely unique power amplifier. It allies purist amplifying devices with the power and solidity required to control modern audiophile loudspeakers. The most noticeable feature of this amplifier is the 300B filamentary triode output tube. Originally designed by Western Electric in 1935 (Footnote 1), it has several extremely desirable features that have kept it in continuous production since that time.
UNPACKING The Renaissance One-Forty is double boxed for the greatest possible protection during shipping. Tubes are packed individually to prevent damage, and must be fitted to the amplifier before installation can proceed. Each tube socket is covered by a small round sticker. On this sticker is a number that corresponds to a numbered sticker on each tube. Fit each tube into the matching socket, first removing the sticker from the amplifier and the tube. No bias level adjustment is required.
INSTALLING NEW OUTPUT TUBES Replacement 300B output tubes should be purchased only from VAC. Output tubes are type 300B. It is important that the tubes be checked for any tendency to mechanical or electrical shorts (see Safety Notice at the front of this manual). It is desirable that tubes be in matched quartets for each channel, and be close to the "bogey" values for the major parameters. Make certain that each tube fits firmly in its socket. Refer to Figure 2 for the location and types of tubes.
TIPS & ADVICE A Word About Tubes in General It is a truth that each brand of tube sounds different in a particular high resolution circuit. This is because no two manufacturers make a tube type in quite the same way, and the central tendencies of the performance parameters will differ slightly with each maker. To emphasize the point, examine the plate structure of any two 6SN7 from different manufacturers will probably find that they may not even the same shape and size.
TIPS & ADVICE A Word About Output Tubes Your VAC Amplifier uses the 300B or 300A filamentary triode. It is strongly recommended that replacement tubes be purchased only from VAC, as stated in the Safety Notice at the front of this manual. If, however, you want to customize the sound to your tastes, be aware that as with interconnects and speaker cables, each tube manufacturer's 300B tends to have a distinct sound.
TJ (mesh anode): Manufacturer indicates that it can not withstand full 300B specifications; therefore not recommended. Please note that firms such as Gold Aero, RAM, and Penta do not design or manufacture their own 300B tubes. Various US companies marketed 300B tubes during the 1950's. Not much is known about their quality. A Word About Low Level Tubes The Voltage Amplifier/Phase Splitter and driver tubes in the Renaissance Seventy/Seventy is the 6SN7 medium mu octal twin triode.
TIPS & ADVICE A Word About Feedback Two front panel controls (one for each channel) are provided by which controlled amounts of loop negative feedback may be introduced. The settings, in order, are as follows: no global feedback at all 2 dB negative feedback 3 dB negative feedback 4 dB negative feedback 5 dB negative feedback 6 dB negative feedback A given amount of feedback reduces the sensitivity of the amplifier by that amount.
TIPS & ADVICE Tuning Your System The VAC Renaissance has unparalleled opportunities for fine tuning your system for best subjective reproduction. At first glance this may seem a bit intimidating, but it's actually quite easy to do. Let's go step by step from the beginning. 1) Start with the Ground switch at "AF" and the two Feedback controls at "0." Connect the loudspeakers to the highest tap that matches the minimum impedance rating of your speakers.
SPECIFICATIONS The VAC Renaissance One-Forty has been developed with the critical ear as the major arbiter of quality, with both conventional and unique measurements providing insight and guidance as necessary. The lack of emphasis on measurements is due to the fact that engineering's arsenal of equipment and techniques do not operate on the pattern recognition principals that control human perception of sound.
WARRANTY Your equipment is warranted for a period of thirty (30) days from the date of purchase. In addition, if the registration card(s) is received by VAC along with a copy of your sales receipt from an authorized VAC dealer within this thirty days, a service contract will be extended to cover your equipment for five (5) years (tubes excepted). Receipt of your registration card will be confirmed in writing by VAC: it is important that you call VAC if you do not receive this confirmation.
