Features
| Brand | Cary Audio |
|---|
Tech Specs
- Circuit Type - Class A, Class A/B, Class B, Pure Balanced Design
- Power Output - Up to 150 watts class B - 110 Watts, Class A/B - 70 Watts, Class A
- Inputs - Single-Ended RCA; Balanced XLR
- Input Sensitivity - 2.0 Volts for full output power
- Input Impedance - 100k Ohms – RCA unbalanced - 200k Ohms – Balanced (XLR) - Noise and Hum - >80 dB below rated output
- Frequency Response - 20 Hz to 20 KHz, + 0.5 dB
- Tube Complement - 1 ea – 6CA7 Current Source Tube - 1 ea – 6SL7 Input Tubev - 2 ea – 300B Driver Stage Tubes - 2 ea – 845 Output Tubes
- Power Transformer(s) - 1 ea – EI Laminate, 200% Duty Cycle
- Output Transformer(s) - 1 ea – EI Laminate, Air Gap, 200% Duty Cycle
- Resistors - 1% Metal Film
- Capacitors - Mundorf SilverGold
- Power Supply Capacitors - 4 ea – 1500µF @ 450 VDC
- AC Cord - 3 Conductor, Detachable
- AC Power Requirements - 117/234 VAC @ 50/60 Hz
- Consumption - 280 watts – Operation
- 76 watts – Standby
- Warm-Up Time - 5 Minutes
- Break-In Time - 100 hours of playing time
- Finish - Anthracite black chassis with silver or black aluminum faceplate
- Weight - 90 lbs
- Dimensions - 10″ H x 12.25″ W x 24 ” D
Product Description
The Cary Audio CAD-211FE Valve MonoBlok Power Amplifier is the most powerful monoblok amplifier made by Cary Audio. It can output 150 watts in class B mode. Additionally, it can operate in pure Class A with an output power of 70 Watts. To get the best possible channel separation these are mono units and two units are required for stereo. Moreover, the operating condition of the amplifier can be adjusted by a bias control along with a front-mounted meter.
Notably, 845 output valves are used. Additionally, there are three taps on the output transformer for 4, 8, and 16 Ohm speakers. Capacitors are by Mundorf and audio grade, with a polypropylene dielectric that has a 99% silver and 1% gold metallization layer.
High build quality
Most of the Cary amplifier range, including the Cary Audio CAD-211FE Valve MonoBlok Power Amplifier, use point-to-point wiring in their construction. This is more durable and reliable than printed circuit boards. As a cost-cutting measure, most manufacturers began using PCBs in the 1960’s. However, they are not ideal for valve circuits as valves run hot.
The constant heating and cooling cycle tends to cause the soldered joints to crack, leading to unreliability. Notably, the case is very strong to hold the heavy transformers and features a thick silver or black anodized front panel. The on-off switch is mounted on the top of the unit along with the massive power and output transformers. Inputs consist of a standard RCA connector or a balanced XLR connector.
Circuit operation
The Cary Audio CAD-211FE Valve MonoBlok Power Amplifier has a complex amplifier circuit. First, a 6SL7 input valve connects to the audio source. This operates as a dual triode class A preamplifier stage. Secondly, the first stage feeds a 6CA7 current source valve. This is capacitor coupled to the 300B driver valve. A front-mounted bias meter monitors the operating conditions of the output stage. The output is via a pair of powerful 845 valves.
Notably, there is also an interstage transformer that has been carefully designed to have a flat frequency response. To obtain the best possible performance the Cary Audio CAD-211FE Valve MonoBlok Power Amplifier has three operating modes. These are employed automatically as the volume of the music increases. For powers up to 70 watts pure Class A is used.
Then up to 110 watts Class A/B is gradually switched in. Beyond that, up to 150 watts, Class B is used. The output transformer is the final part of the chain and converts the high output impedance of the Valve stage (8000 ohms) to a level suitable to drive a speaker. Three taps are provided for 4, 8, Or 16-ohm speakers.
A word about capacitors
Capacitors were once the weak point in valve amplifiers and radios. They were made with a paper dielectric and this tends to deteriorate over time. Capacitors can have several hundreds of volts placed on them and any electrical leakage can upset the biasing of the next stage. As a result, the valve may overheat and burn out. However modern capacitors are made of polypropylene or polystyrene and are designed to last for decades.
Notably, the Cary Audio CAD-211FE Valve MonoBlok Power Amplifier uses capacitors by Mundorf. These are the SilverGold type and have a polypropylene dielectric with a 99% silver and 1% gold metallization layer. Additionally, electrolytic capacitors also suffered from the electrolyte drying up due to heat. However modern materials and construction methods mean that the new types are long lasting and designed to provide many years of service.
