A matched set of three Classe Sigma MONO monoblocks, each rated at 350W into 8 ohms and 700W into 4 ohms, with balanced and single ended inputs. Ideal for the three front channels of a cinema system. Out of production, privately owned and offered through Dreamcrest Audio, individually or within the complete collection. This is a set of three Classe Sigma MONO monoblock power amplifiers, each rated at 350W into 8 ohms and 700W into 4 ohms in a single rack width chassis. Three of them is the natural number for the front left, centre and right channels of a serious cinema system. The Sigma range is out of production and now appears only in Classe's support archive, so sets like this come up rarely. These amplifiers belong to a private client and are offered through Dreamcrest Audio. B-stock, in very good condition, supplied in its original packaging.What it doesA monoblock handles one channel only, with its own chassis, its own power supply and its own mains lead. In a cinema that means the centre channel, which carries almost all of the dialogue, is no longer sharing a transformer with four other channels during a loud scene. Each Sigma MONO takes a balanced XLR or single ended RCA feed from a processor and delivers 350W into 8 ohms, doubling to 700W into 4 ohms, which is what you want from an amplifier driving a real loudspeaker load.How it sounds and where it fitsClasse built the Sigma series to be quiet and composed rather than forward, and a noise floor 109 dB below peak output into 8 ohms is consistent with that. Used across the front three channels, the benefit is that dialogue stays clear when the score and effects are loud. They suit demanding floorstanding or in wall speakers with a difficult impedance curve, and partner naturally with the Classe Sigma SSP MK2 and Sigma AMP5 from the same collection.Key featuresThree matched monoblocks, one per channel350W rms into 8 ohms and 700W rms into 4 ohms per amplifierBalanced XLR and single ended RCA inputsSignal to noise of 109 dB below peak output into 8 ohmsLow standby draw of 0.5 W at 230 VSingle rack width chassis only 95 mm tallPart of the discontinued Classe Sigma seriesTechnical specificationsFrequency response: 10Hz to 20kHz, 1 dB down into 4 ohmsTHD: under 0.012% at 1kHz, one eighth power into 8 ohmsInput impedance: 100k ohms balanced, 50k ohms single endedDimensions each: 433 mm wide, 370 mm deep, 95 mm highWeight each: 10.0 kgCondition and what is includedB-stock, in very good condition, supplied in its original packaging. The owner bought it new about three to four years ago. This unit belongs to a private client and is offered for sale through Dreamcrest Audio, which is not the owner. It is not new dealer stock, and no manufacturer warranty is offered or implied. Condition and inclusions are confirmed to you in writing before purchase.Frequently asked questionsMust I take all three?They are listed and priced as three matched units, which is how they were used. Ask us if you need a different arrangement.Can they be used in a stereo system?Yes. Two of them make a conventional monoblock pair for a two channel system, leaving the third for a centre channel if you later add one.Can I buy them on their own?Yes. They are sold as this set, or as part of the complete Home Cinema Collection bundle from the same owner.To ask about condition or arrange a listen, use the enquiry button on this page.
Dreamcrest Audio Fidelity Ltd, Nicosia. Specialist hi-fi and high end audio, 20+ years in the audio business. Call or message for availability, demonstration and delivery.
