Music, like meditation, can happen only in the living moment, here and now. This immediacy, its breathing and pulsating nature, is what vivifies every performance.

Amplification of ultimate refinement can reproduce performance that retains every nuance of musical expression. Like the Canasya monoblock system from Cadence. Its nonpareil musicality springs from an innovative combination of the legendary 845 carbon triode vacuum tube and hi-tech solid state components.

A unique driver concept creates greater linearity for driving high power valves than ever before, and eliminates residual distortion to below audible levels. From warm and pure class A operation up to 50 watts (where 95 percent of the music happens) to a pulse-pounding 200 watts rms per channel, the Canasya monoblocks are well qualified to live up to their Sanskrit name, which denotes delightful.

Aided by pioneering features like precision biasing, electronic aging compensation, valve life indication meters (which indicate health and status of each valve), optimum damping at low frequencies for spot-on bass performance and an uncritical 2 to 8 Ohms load of output impedance.

Hybrid 845 monoblocks, < 0.3 % distortion at 100 W, < 0.015 % at listening level (10 W)

Why a solid state drive section? Driving a triode like the 845 fully requires some 470Vpp on the grids, which means if valve-driving is used, another power valve, at least medium power, is needed. This tube does drift a lot, besides the large tolerances in Ia/Ug parameters from specimen to specimen. Not a good basis for DC coupling --- DC coupling was preferred if possible, to avoid the effects of coupling capacitors.

Since the amplification factor of the additional medium power tubes is also not too exciting, this meant another, third, preamp stage would be necessary, and to get some feedback headroom, a fourth stage comes in.

The associated results of 4 times distortion, noise, and capacitor coupling required a new design paradigm, one of which turned out to be effective and easy, yet extremely fast: A transistor in a base-grounded configuration (normally used for high frequency amplification), turned out to be very beneficial:

• Drift and DC errors are more easily controlled
• Ultra fast, faster than the tube (30 Mhz)
• Current gain close to one, but voltage gain in the region of a thousand times --- perfect for achieving the high grid drive voltages.
• The practically X1 current gain also seems to do one miracle: The typical transistor sound (that little metallic-harsh element in it) seems to be much less in this base-grounded circuit.

A transistor was sourced (only one mil spec unit with the desired VCEmax was found, the designer had to sign an agreement to not use it for mil purposes (American sales restrictions apply), and it is now working well driving the grids to the very max. That also provides more output than is normally available from the 845's. And it's DC coupled!

For feedback headroom, a preamp stage was included, using the cream of the crop: Burr Brown is still the favorite there, so low offset, high speed single OP's are used to do this, and still - it's DC coupled there. Because of this, no shifting of bias condition is possible, no matter what signals come in.

Bias is also measured constantly and if the tubes should change their characteristics over time (which they do) it is automatically held constant. To avoid output transformer saturation when subsonics are coming in, however, ONE capacitor was included in the input connection, but thats it.

Damping factor: Most tube amps have poor bass damping charactertistics, which are incompatible with many otherwise excellent loudspeaker designs, so one design goal was to have excellent bass damping characteristics. This was achieved through a frequency-dependent feedback method, which applies much more feedback at low frequencies, achieving enough damping for most speakers on the market. This also helps the high frequency performance, because less there means more stability and less phase shift, which translates into better impulse response.

Additional niceties include multiple separated power supplies so no groundloop exists anywhere, a thought-through grounding concept (Star grounding) and a separated signal ground star, so any intereference between power supplies and the audio-signal is minimized. The actual main amp board is separately housed from the rest of the electronics and fully enclosed, further eliminating interferences. And last but not least, high Q Van den Hul cables are used for all critical wires, including DC supply wiring.

6 Ohm terminals were chosen because most loudspeakers live in this neighborhood. Also, it is quite well matched to either 4 and 8 Ohms, with only minor max power loss. Taps were not used, in order not to degrade the custom output transformer's performance.