Specifications Click here to view product brochure Click here to view owner’s manual Click here to view photo gallery Overview The Belles 150A Reference power amplifier is the continuing refinement of the superb amplifier design of Dave Belles. Design that exemplifies the science of accurately portraying the art of music in a way that stirs the soul. It is one thing to engineer a product that is reliable, it is another to create a product that allows the music to come through as it was meant to, in such a way that it allows you to forget you are listening to a recording. It is a product that reveals every nuance of the system without emphasizing or adding coloration. It is an amplifier that truly disappears, the ultimate compliment for any amplifier product. The 150A Reference is one of those rare products that meld art and science in a heart gripping, soul stirring synergy. The 150A Reference utilizes a dual mono design topology. This gives the amplifier better isolation between channels. Soundstage imaging is improved, offering true soundstage width and depth. Instrument placement and layering are more accurate, revealing the depth and texture of each instrument or vocalist. Each channel shares a common 1000 VA toroidal transformer. By using a larger single transformer, rather than 2 smaller ones as in typical dual mono designs, stronger and cleaner bass is maintained. Each channel of the Belles 150A Reference is an all in one integrated assembly. The circuit components are mounted directly to the heat sink, eliminating the need for additional wiring that can produce inconsistencies from one channel to the next. The 150A Reference amplifier circuit consists of 3 stages: • an input stage with matched dual J-FETS/Bi-polars in a cascaded differential pair • a voltage gain stage using bipolar transistors • a final stage using a source follower with 8 power mosfet, class B biased Negative feedback is used to stabilize the gain and reduce distortion, noise and output impedance. DC stability and speaker offset voltage is properly regulated by using an accurately trimmed DC servo amplifier. This method introduces less coloration than using coupling capacitors. The 150A Reference has been engineered to be among the most effective products on the market at dampening the back EMF from speakers. The results are heard as tightly controlled bass that has detail, texture and separation. The technology behind the Belles 150A Reference is impressive. Even more impressive, however, is the sound. Listening to the 150A Reference has been described as a memorable experience; you feel as though you are part of the musical performance. Features • Dual-mono design topology. • Each channel an integrated circuit assembly • Gold-plated oxygen free copper binding posts and wire • Gold-plated input connectors accommodate balanced and unbalanced signals • 1000 VA toroidal power transformer, to eliminate stray magnetic fields • A pair can be used as mono-block units • Uses polypropylene capacitors • All power resistors are non-inductive ceramic • 1% metal film resistors used throughout • 3 stages of amplification • Negative feedback circuit stabilizes gain, reduces distortion, noise and output impedance • Uses a trimmed DC servo amplifier to maintain DC stability and speaker offset voltage. • Available with either a silver or black anodized front panel A pair of 150A Reference amplifiers have exceptional performance and power at 500 Watts per channel into 8 ohms! brochure__150a_ref_amp.htmlmanual__150_reference.htmlGallery/Gallery.htmlshapeimage_1_link_0shapeimage_1_link_1shapeimage_1_link_2


Power Rating -



 Frequency response -


Distortion -


Damping factor -


Peak Current -


Input Sensitivity -


Input Impedance -


Hum and Noise -


Gain -


Inputs -


Dimensions -


Shipping Weight -


Power Rating -


Warranty -


125 watts X 2 into 8 ohms  (500 watts mono-block configuration)
250 watts X 2 into 4 ohms


0.2 to 100,000 Hz


Less than 0.1%  at rated power


Over 1,000


Over 30 amperes


1.4 volts for rated power


100,000 ohms


>100 dB


21 voltage ratio or 26.44 dB


Unbalanced only (single ended)


17" W x 5.25" H x 13" D


48 lbs


120 VAC, 8.0A fuse (240 VAC optional)


5 years

Home News Products Reviews Gallery Dealers Blog About Us ContactsHome.htmlNews.htmlProducts_menu.htmlReviews.htmlGallery/Gallery.htmlDealers.htmlBlog_intro.htmlAbout_us.htmlContacts.htmlshapeimage_3_link_0shapeimage_3_link_1shapeimage_3_link_2shapeimage_3_link_3shapeimage_3_link_4shapeimage_3_link_5shapeimage_3_link_6shapeimage_3_link_7shapeimage_3_link_8