there are numerous ways to implement a vacuum tube in the circuitry of a dac
the devil is ALWAYS in the details, circuit, tube, associated parts, associated circuitry, power supply, isolation - all of it works together and each element interrelates with others to produce the sound - examples:
gary dews’ border patrol unit uses the ez80 tube rectifier in the power supply section only - not the amplification stage
jiun-hsien at mhdt uses his single 5670 dual triode as a buffer in the output circuit of the orchid/stockholm/pagoda etc etc, main amplfication is actually solid state, the buffer circuit provides a 10-15% lift and a little tubey flavor - the jolida guys do the same with their FX tube dac but they use 12ax7’s one for each channel
vlad at audio mirror runs his 5977 sub miniatures as the actual driver of his tubador’s output stage... thus the tube circuit is providing the full gain and impedance match to the receiving preamp/amp
frank van alstine in his lovely old FET TOPP dacs used 12ax7’s in his main driver stage, one for each channel
so it depends... one needs to understand in detail what you are dealing with, what you are listening to, how it will or won’t affect the sound - each designer makes decisions based on his objectives for sound, cost, reliability and so on...
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there are also other ways to create an ’analog-sounding’ dac, full of dimensionality and warmth and glow in the sound without a vacuum tube - witness cees rujtenberg at metrum/sonnet, wesley at neko and the folks at lumin who use lovely old school output transformer coupling of the ss output stage ... so there are many ways to achieve wonderful results
the devil is ALWAYS in the details, circuit, tube, associated parts, associated circuitry, power supply, isolation - all of it works together and each element interrelates with others to produce the sound - examples:
gary dews’ border patrol unit uses the ez80 tube rectifier in the power supply section only - not the amplification stage
jiun-hsien at mhdt uses his single 5670 dual triode as a buffer in the output circuit of the orchid/stockholm/pagoda etc etc, main amplfication is actually solid state, the buffer circuit provides a 10-15% lift and a little tubey flavor - the jolida guys do the same with their FX tube dac but they use 12ax7’s one for each channel
vlad at audio mirror runs his 5977 sub miniatures as the actual driver of his tubador’s output stage... thus the tube circuit is providing the full gain and impedance match to the receiving preamp/amp
frank van alstine in his lovely old FET TOPP dacs used 12ax7’s in his main driver stage, one for each channel
so it depends... one needs to understand in detail what you are dealing with, what you are listening to, how it will or won’t affect the sound - each designer makes decisions based on his objectives for sound, cost, reliability and so on...
**********************
there are also other ways to create an ’analog-sounding’ dac, full of dimensionality and warmth and glow in the sound without a vacuum tube - witness cees rujtenberg at metrum/sonnet, wesley at neko and the folks at lumin who use lovely old school output transformer coupling of the ss output stage ... so there are many ways to achieve wonderful results