We are pleased to announce the availability of the custom built Mono Blocks. A lot of thought, planning, and careful design has gone into this product and we think it provides a wonderful opportunity for the music lover or even extreme audiophile, to have the best in Mono Block Technology.... Audio Note Technology.

The features are numerous:

• Power Amplifier design with 2V input sensitivity (an ideal match for M2 or M3 Line Pre-Amplifier).

• Can be configured for 300B, 2A3, Parallel 300B, or Parallel 2A3.

• Power supply and triode/input tube are all hard-wired.

• Input stage using 6SH7 followed by Audio Note designed Interstage Transformer.

• Supports the standard Kit1 output transformer AND the Trans-300 Double C-core output transformer.

• The interstage transformer available as an IE core but upgradeable to C-core.

• 25" in length and 8.5" width.

• Our Custom Built units will utilize a combination of Large Black Gate/Jensen/Mundorf  capacitors within the power supply, cathode bypass and other areas.

• No film caps used in the signal path

• Input RCA to tube valve base is done via resistor for a "no wire" input signal path..

• Using high quality WE 8 pin valve bases and the AN 300B valve base.

The new Mono Block amplifiers are comprised of a 6SH7 input tube - this was selected by Andy Grove for a number of technical reasons related to input impedance and input sensitivity of the power amplifier in mating with the M3 Line.

The 6SH7 is fairly readily available and not overly expensive (yet). It comes in both a glass tube version and with a black metal case on it. NOS tubes are available in the $5 USD range and up. The 6SH7 then feeds an interstage transformer designed specially by Audio Note for use in the Mono Blocks. The Interstage transformer design style is currently used on Audio Note's top of the line On Gaku 211 amplifiers. Back to the circuit - The Interstage transformer drives the Triode 300B or 2A3 in single ended mode. The Triode then drives the output transformer - either the TRANS-152 or the Double C-Core TRANS-300 depending on model purchased.

The power supply uses the CHOKE-165 (also used in the Ongaku) along with the H301067 mains transformer designed for both 2A3 and 300B use. Cleverly, they are using a 5Y3 tube rectifier for single triode operation and a 5U4G for parallel - both tubes using the same power supply circuit!

The input sensitivity is around 2V which is ideal for a power amplifier and ideal when mating with Audio Note's M2 or M3 Line pre-amplifiers.

These amplifiers utilize the top of the line Valve Sockets in the Mono Block for both 8 pin and 4 pin as well as using Audio Note Hardwire Tag Strips.

The unique design style makes use of an interstage transformer on each channel - rather than having an additional tube driver stage, the interstage transformer takes over this task for ultimate authority! The power supply and driver circuitry is all hardwired. The power supply supports large black gate or Jensen Electrolytics that protrude through the chassis. The mechanical design of the unit is second to none using all stainless steel metric hardware; countersunk screws and more. Then there is the sound - In combination with an AudioNote M3 transformer coupled pre-amp the interstage Mono Block provides a level or realism and detail that you may not have ever experienced from a product in this price range.

The Mono Block was designed in the UK by Andy Grove after listening to the requirements of the many audiophiles who have wanted a Mono Block product. He suggested that using an interstage transformer (as used in the highest level AN finished products) was the ideal solution. An IE core interstage transformer was built specifically for the this product.

"We built the first prototype in the UK last fall and then I built two prototypes in Canada for testing over the winter - the results were very impressive! When the prototype chassis arrived and the first pair was put to the test I have to admit I was blown away by the results. Coupled with an M3 line pre-amplifier, the level of sound quality astonished me - almost like the first time I listened to SET."

We are making available a fast download / low resolution copy of the instruction manual so you can see for yourself the quality and detail of the build as well as the time involved in assembling these products.

Click here to view the manual.

Standard Configurations and Pricing

All prices below are for a complete, fully assembled pair of mono bloc amplifiers. Our custom builds include full assembly, testing and 1 year workmanship warranty. On the Double C-Core versions, we use a total of 4 pieces Mundorf M-TubeCap film capacitors in part of the the power supply.

All Audio Note Custom products go through full bench testing for 2-4 hours after assembly and then into a system to be run for an additional 12 hours. After this system burn-in, they go back to the bench for final testing before being packed up and shipped out to you for your listening enjoyment.

The price also includes us ordering the product and having it shipped to our facility for the assembly. Does not include shipping to you after completion.

InterStage Mono Block - IE Core - Single Triode (specify 2A3 or 300B)

Level A - $4,199 USD - The entry level Mono Blocks provide you with a unique amplifier at a cost effective price with the allowance for easily installed future upgrades. The Level A will use 1W Beyschlag Resistors, Good quality Electrolytics, Jensen PS caps, PTFE silver plated copper wire, Western Electric and Ceramic Valve Bases, AN Hardwiring Tags. Level B - $4,399 USD - The Level B version upgrades components to 1W tantalum resistors on the driver tube and power supply sections. We also utilize Black Gates on the cathodes of the 6SH7 and 300B. Level C (Signature) - $4,699 USD - Moving up to the Signature version upgrades the resistors to 2W tants on the power supply and tube driver sections. We also use Black Gates on the filament circuitry and tube cathodes and provide an optional power supply plate to max out the Power supply capacitors

InterStage Mono Block - Double C-Core - Single Triode (specify 2A3 or 300B)

Level C Signature - $6,999 USD - EXtreme SET  Comes standard with the best quality TRANS-300 double C-core output transformers, Black Gate / Mundorf power supply, Black Gate on the filament circuits and tube cathodes and Tantalum resistors throughout the driver and power supply sections - Black Gates on the filament circuits and tube cathode

InterStage Mono Block - Double C-Core - Parallel Triode (specify 2A3 or 300B)

Level C Signature - $7,249 USD - EXtreme PT (parallel triode)TRANS-305 double C-core output transformers, Black Gate / Mundorf power supply, Black Gate on the filament circuits and tube cathodes and Tantalum resistors on the driver and power supply sections - Black Gates on the filament circuits and tube cathodes

 

 

Bybee Options:

This option is for the use of Bybee Purifiers at the input signal of each amplifier.

Standard Bybee: $200 installed

Gold Bybee:       $475 installed