Chassis can be quite heavy. Dissipante style chassis structural integrity and low noise is made possible by the 2mm galvanized base and the aluminium heatsinks. The top and bottom, back and front have to be also using atleast 2mm aluminium. For pesante style chassis, structural integrity and low noise is made possible by the 2mm galvanized base and 2mm steel sides, The top and bottom, back and front have to be also using atleast 2mm aluminium. This makes these chassis heavy, openings on the top although great for chimney effect make the amplifier vulnerable to spills. On the other hand the two piece chassis is lighter and much easier to work with. A fifth foot is needed in the center but this one is attached with glue.
How do you measure it? It is open loop gain from inverted input to output without feedback circuit or open loop gain with feedback circuit? (they differ by loop gain attenuation).
Another question: what is phase margin for this amplifier? (or better phase till 0dB gain)?
This circuit is too complicated for that it does. The extra cascode stage between input and vas is unnecessary.
We are talking about dethroning SYMEF, so please provide information I've requested, to make this duel fair.
When it comes down to a set of equally good solutions , it will come down to a matter of personal taste or preference based on some context.
What is unusaual in this graph? Looks like typical open loop gain of amplifier with low frequency pole at circa 400Hz.
@Zbig. There are quite a few amplifiers with that voicing. The reason one might not want a king of the hill type of amplifier may result in the way the brain handles stimulus, pineapples and chocolates are wow but they numb the senses. Any ranking of amplifiers may not have solid basis. The field of audio has one foot in brain studies and another in electronics and acoustics, what you perceive is highly biased by mental state. The brain to stimulus interaction is quite interesting, packaging the same amplifier in two different chassis, one extra ordinary and the other cheap also affects how we process the sound.
Music, scenery and company can uplift or depress. Stimulus transports the brain into different worlds. This is already a facet of time travel or inter dimensional travel. What path the brain chooses to traverse in this space defines our reality. People react to bad sound differently others are more immune. The crowd at diyaudio make an interesting lot. If you love and have longed for a brand , then only that brand will sound right.
This is a very complex discussion: isn't it what many people define it as psychoacoustics? However, I express my very generic idea of the audio field, without taking any type of amplifier as an example. In my opinion we need to start from a base, and this base is electronics, mathematics and laboratory measurements: we are talking about absolutely objective data, they are universally recognized by all. The other variable that comes into play is our perception of sound, so the ear, the brain and everything that follows (mental states, emotions etc etc) come into play. Here we enter a completely personal and subjective world: no one can decide for the other. To conclude I would say that our personal taste and pleasure when we listen to a sound lies somewhere between these two, and honestly I couldn't say how much one influences the other or vice versa. Un saluto Ros
The Chassis bottom ,front and back are now in white while the top and sides are black, ended up way cooler and works great for dissipation
The front can fit any volume potentiometers, the back will fit most hifi RCA , binding posts, IEC , fuse holder and switch